FFmpeg
ac3enc.c
Go to the documentation of this file.
1 /*
2  * The simplest AC-3 encoder
3  * Copyright (c) 2000 Fabrice Bellard
4  * Copyright (c) 2006-2010 Justin Ruggles <justin.ruggles@gmail.com>
5  * Copyright (c) 2006-2010 Prakash Punnoor <prakash@punnoor.de>
6  *
7  * This file is part of FFmpeg.
8  *
9  * FFmpeg is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * FFmpeg is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with FFmpeg; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23 
24 /**
25  * @file
26  * The simplest AC-3 encoder.
27  */
28 
29 #include <stdint.h>
30 
31 #include "libavutil/attributes.h"
32 #include "libavutil/avassert.h"
34 #include "libavutil/crc.h"
35 #include "libavutil/emms.h"
36 #include "libavutil/internal.h"
37 #include "libavutil/mem.h"
38 #include "libavutil/mem_internal.h"
39 #include "libavutil/opt.h"
40 #include "libavutil/thread.h"
41 #include "avcodec.h"
42 #include "codec_internal.h"
43 #include "config_components.h"
44 #include "encode.h"
45 #include "me_cmp.h"
46 #include "put_bits.h"
47 #include "audiodsp.h"
48 #include "ac3dsp.h"
49 #include "ac3.h"
50 #include "ac3defs.h"
51 #include "ac3tab.h"
52 #include "ac3enc.h"
53 #include "eac3enc.h"
54 
55 #define SAMPLETYPE_SIZE(ctx) (sizeof(float) == sizeof(int32_t) ? sizeof(float) : \
56  (ctx)->fixed_point ? sizeof(int32_t) : sizeof(float))
57 
58 typedef struct AC3Mant {
59  int16_t *qmant1_ptr, *qmant2_ptr, *qmant4_ptr; ///< mantissa pointers for bap=1,2,4
60  int mant1_cnt, mant2_cnt, mant4_cnt; ///< mantissa counts for bap=1,2,4
61 } AC3Mant;
62 
63 #define CMIXLEV_NUM_OPTIONS 3
64 static const float cmixlev_options[CMIXLEV_NUM_OPTIONS] = {
66 };
67 
68 #define SURMIXLEV_NUM_OPTIONS 3
71 };
72 
73 #define EXTMIXLEV_NUM_OPTIONS 8
77 };
78 
79 /* The first two options apply only to the AC-3 encoders;
80  * the rest is also valid for EAC-3. When modifying it,
81  * it might be necessary to adapt said offset in eac3enc.c. */
82 #define OFFSET(param) offsetof(AC3EncodeContext, options.param)
83 #define AC3ENC_PARAM (AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM)
85 /* AC-3 downmix levels */
86 {"center_mixlev", "Center Mix Level", OFFSET(center_mix_level), AV_OPT_TYPE_FLOAT, {.dbl = LEVEL_MINUS_4POINT5DB }, 0.0, 1.0, AC3ENC_PARAM},
87 {"surround_mixlev", "Surround Mix Level", OFFSET(surround_mix_level), AV_OPT_TYPE_FLOAT, {.dbl = LEVEL_MINUS_6DB }, 0.0, 1.0, AC3ENC_PARAM},
88 /* audio production information */
89 {"mixing_level", "Mixing Level", OFFSET(mixing_level), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, 111, AC3ENC_PARAM},
90 {"room_type", "Room Type", OFFSET(room_type), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, AC3ENC_OPT_SMALL_ROOM, AC3ENC_PARAM, .unit = "room_type"},
91  {"notindicated", "Not Indicated (default)", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_NOT_INDICATED }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "room_type"},
92  {"large", "Large Room", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_LARGE_ROOM }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "room_type"},
93  {"small", "Small Room", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_SMALL_ROOM }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "room_type"},
94 /* Metadata Options */
95 {"per_frame_metadata", "Allow Changing Metadata Per-Frame", OFFSET(allow_per_frame_metadata), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, AC3ENC_PARAM},
96 {"copyright", "Copyright Bit", OFFSET(copyright), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, 1, AC3ENC_PARAM},
97 {"dialnorm", "Dialogue Level (dB)", OFFSET(dialogue_level), AV_OPT_TYPE_INT, {.i64 = -31 }, -31, -1, AC3ENC_PARAM},
98 {"dsur_mode", "Dolby Surround Mode", OFFSET(dolby_surround_mode), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, AC3ENC_OPT_MODE_ON, AC3ENC_PARAM, .unit = "dsur_mode"},
99  {"notindicated", "Not Indicated (default)", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_NOT_INDICATED }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dsur_mode"},
100  {"on", "Dolby Surround Encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_MODE_ON }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dsur_mode"},
101  {"off", "Not Dolby Surround Encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_MODE_OFF }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dsur_mode"},
102 {"original", "Original Bit Stream", OFFSET(original), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, 1, AC3ENC_PARAM},
103 /* extended bitstream information */
104 {"dmix_mode", "Preferred Stereo Downmix Mode", OFFSET(preferred_stereo_downmix), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, AC3ENC_OPT_DOWNMIX_DPLII, AC3ENC_PARAM, .unit = "dmix_mode"},
105  {"notindicated", "Not Indicated (default)", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_NOT_INDICATED }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dmix_mode"},
106  {"ltrt", "Lt/Rt Downmix Preferred", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_DOWNMIX_LTRT }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dmix_mode"},
107  {"loro", "Lo/Ro Downmix Preferred", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_DOWNMIX_LORO }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dmix_mode"},
108  {"dplii", "Dolby Pro Logic II Downmix Preferred", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_DOWNMIX_DPLII }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dmix_mode"},
109 {"ltrt_cmixlev", "Lt/Rt Center Mix Level", OFFSET(ltrt_center_mix_level), AV_OPT_TYPE_FLOAT, {.dbl = -1.0 }, -1.0, 2.0, AC3ENC_PARAM},
110 {"ltrt_surmixlev", "Lt/Rt Surround Mix Level", OFFSET(ltrt_surround_mix_level), AV_OPT_TYPE_FLOAT, {.dbl = -1.0 }, -1.0, 2.0, AC3ENC_PARAM},
111 {"loro_cmixlev", "Lo/Ro Center Mix Level", OFFSET(loro_center_mix_level), AV_OPT_TYPE_FLOAT, {.dbl = -1.0 }, -1.0, 2.0, AC3ENC_PARAM},
112 {"loro_surmixlev", "Lo/Ro Surround Mix Level", OFFSET(loro_surround_mix_level), AV_OPT_TYPE_FLOAT, {.dbl = -1.0 }, -1.0, 2.0, AC3ENC_PARAM},
113 {"dsurex_mode", "Dolby Surround EX Mode", OFFSET(dolby_surround_ex_mode), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, AC3ENC_OPT_DSUREX_DPLIIZ, AC3ENC_PARAM, .unit = "dsurex_mode"},
114  {"notindicated", "Not Indicated (default)", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_NOT_INDICATED }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dsurex_mode"},
115  {"on", "Dolby Surround EX Encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_MODE_ON }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dsurex_mode"},
116  {"off", "Not Dolby Surround EX Encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_MODE_OFF }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dsurex_mode"},
117  {"dpliiz", "Dolby Pro Logic IIz-encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_DSUREX_DPLIIZ }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dsurex_mode"},
118 {"dheadphone_mode", "Dolby Headphone Mode", OFFSET(dolby_headphone_mode), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, AC3ENC_OPT_MODE_ON, AC3ENC_PARAM, .unit = "dheadphone_mode"},
119  {"notindicated", "Not Indicated (default)", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_NOT_INDICATED }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dheadphone_mode"},
120  {"on", "Dolby Headphone Encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_MODE_ON }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dheadphone_mode"},
121  {"off", "Not Dolby Headphone Encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_MODE_OFF }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dheadphone_mode"},
122 {"ad_conv_type", "A/D Converter Type", OFFSET(ad_converter_type), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, AC3ENC_OPT_ADCONV_HDCD, AC3ENC_PARAM, .unit = "ad_conv_type"},
123  {"standard", "Standard (default)", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_ADCONV_STANDARD }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "ad_conv_type"},
124  {"hdcd", "HDCD", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_ADCONV_HDCD }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "ad_conv_type"},
125 /* Other Encoding Options */
126 {"stereo_rematrixing", "Stereo Rematrixing", OFFSET(stereo_rematrixing), AV_OPT_TYPE_BOOL, {.i64 = 1 }, 0, 1, AC3ENC_PARAM},
127 {"channel_coupling", "Channel Coupling", OFFSET(channel_coupling), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_AUTO }, AC3ENC_OPT_AUTO, AC3ENC_OPT_ON, AC3ENC_PARAM, .unit = "channel_coupling"},
128  {"auto", "Selected by the Encoder", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_AUTO }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "channel_coupling"},
129 {"cpl_start_band", "Coupling Start Band", OFFSET(cpl_start), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_AUTO }, AC3ENC_OPT_AUTO, 15, AC3ENC_PARAM, .unit = "cpl_start_band"},
130  {"auto", "Selected by the Encoder", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_AUTO }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "cpl_start_band"},
131 {NULL}
132 };
133 
135  .class_name = "AC-3 Encoder",
136  .item_name = av_default_item_name,
137  .option = ff_ac3_enc_options,
138  .version = LIBAVUTIL_VERSION_INT,
139 };
140 
142  { "b", "0" },
143  { NULL }
144 };
145 
146 /**
147  * LUT for number of exponent groups.
148  * exponent_group_tab[coupling][exponent strategy-1][number of coefficients]
149  */
150 static uint8_t exponent_group_tab[2][3][256];
151 
152 
153 /**
154  * List of supported channel layouts.
155  */
166  {
167  .nb_channels = 2,
168  .order = AV_CHANNEL_ORDER_NATIVE,
170  },
171  {
172  .nb_channels = 3,
173  .order = AV_CHANNEL_ORDER_NATIVE,
175  },
176  {
177  .nb_channels = 4,
178  .order = AV_CHANNEL_ORDER_NATIVE,
180  },
181  {
182  .nb_channels = 4,
183  .order = AV_CHANNEL_ORDER_NATIVE,
185  },
186  {
187  .nb_channels = 5,
188  .order = AV_CHANNEL_ORDER_NATIVE,
190  },
193  { 0 },
194 };
195 
196 /**
197  * Table to remap channels from SMPTE order to AC-3 order.
198  * [channel_mode][lfe][ch]
199  */
200 static const uint8_t ac3_enc_channel_map[8][2][6] = {
202  { { 0, 1, 2, 3, }, { 0, 1, 3, 4, 2, } },
203  { { 0, 2, 1, 3, 4, }, { 0, 2, 1, 4, 5, 3 } },
204 };
205 
206 /**
207  * LUT to select the bandwidth code based on the bit rate, sample rate, and
208  * number of full-bandwidth channels.
209  * bandwidth_tab[fbw_channels-1][sample rate code][bit rate code]
210  */
211 static const uint8_t ac3_bandwidth_tab[5][3][19] = {
212 // 32 40 48 56 64 80 96 112 128 160 192 224 256 320 384 448 512 576 640
213 
214  { { 0, 0, 0, 12, 16, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48 },
215  { 0, 0, 0, 16, 20, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56 },
216  { 0, 0, 0, 32, 40, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } },
217 
218  { { 0, 0, 0, 0, 0, 0, 0, 20, 24, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48 },
219  { 0, 0, 0, 0, 0, 0, 4, 24, 28, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56 },
220  { 0, 0, 0, 0, 0, 0, 20, 44, 52, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } },
221 
222  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 24, 32, 40, 48, 48, 48, 48, 48, 48 },
223  { 0, 0, 0, 0, 0, 0, 0, 0, 4, 20, 28, 36, 44, 56, 56, 56, 56, 56, 56 },
224  { 0, 0, 0, 0, 0, 0, 0, 0, 20, 40, 48, 60, 60, 60, 60, 60, 60, 60, 60 } },
225 
226  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 24, 32, 48, 48, 48, 48, 48, 48 },
227  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 28, 36, 56, 56, 56, 56, 56, 56 },
228  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 32, 48, 60, 60, 60, 60, 60, 60, 60 } },
229 
230  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 20, 32, 40, 48, 48, 48, 48 },
231  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 24, 36, 44, 56, 56, 56, 56 },
232  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 28, 44, 60, 60, 60, 60, 60, 60 } }
233 };
234 
235 
236 /**
237  * LUT to select the coupling start band based on the bit rate, sample rate, and
238  * number of full-bandwidth channels. -1 = coupling off
239  * ac3_coupling_start_tab[channel_mode-2][sample rate code][bit rate code]
240  *
241  * TODO: more testing for optimal parameters.
242  * multi-channel tests at 44.1kHz and 32kHz.
243  */
244 static const int8_t ac3_coupling_start_tab[6][3][19] = {
245 // 32 40 48 56 64 80 96 112 128 160 192 224 256 320 384 448 512 576 640
246 
247  // 2/0
248  { { 0, 0, 0, 0, 0, 0, 0, 1, 1, 7, 8, 11, 12, -1, -1, -1, -1, -1, -1 },
249  { 0, 0, 0, 0, 0, 0, 1, 3, 5, 7, 10, 12, 13, -1, -1, -1, -1, -1, -1 },
250  { 0, 0, 0, 0, 1, 2, 2, 9, 13, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
251 
252  // 3/0
253  { { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
254  { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
255  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
256 
257  // 2/1 - untested
258  { { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
259  { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
260  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
261 
262  // 3/1
263  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
264  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
265  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
266 
267  // 2/2 - untested
268  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
269  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
270  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
271 
272  // 3/2
273  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 6, 8, 11, 12, 12, -1, -1 },
274  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 6, 8, 11, 12, 12, -1, -1 },
275  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
276 };
277 
278 
279 #define FLT_OPTION_THRESHOLD 0.01
280 
281 static int validate_float_option(float v, const float *v_list, int v_list_size)
282 {
283  int i;
284 
285  for (i = 0; i < v_list_size; i++) {
286  if (v < (v_list[i] + FLT_OPTION_THRESHOLD) &&
287  v > (v_list[i] - FLT_OPTION_THRESHOLD))
288  break;
289  }
290  if (i == v_list_size)
291  return AVERROR(EINVAL);
292 
293  return i;
294 }
295 
296 
297 static void validate_mix_level(void *log_ctx, const char *opt_name,
298  float *opt_param, const float *list,
299  int list_size, int default_value, int min_value,
300  int *ctx_param)
301 {
302  int mixlev = validate_float_option(*opt_param, list, list_size);
303  if (mixlev < min_value) {
304  mixlev = default_value;
305  if (*opt_param >= 0.0) {
306  av_log(log_ctx, AV_LOG_WARNING, "requested %s is not valid. using "
307  "default value: %0.3f\n", opt_name, list[mixlev]);
308  }
309  }
310  *opt_param = list[mixlev];
311  *ctx_param = mixlev;
312 }
313 
314 
315 /**
316  * Validate metadata options as set by AVOption system.
317  * These values can optionally be changed per-frame.
318  *
319  * @param s AC-3 encoder private context
320  */
322 {
323  AVCodecContext *avctx = s->avctx;
324  AC3EncOptions *opt = &s->options;
325 
326  opt->audio_production_info = 0;
327  opt->extended_bsi_1 = 0;
328  opt->extended_bsi_2 = 0;
329  opt->eac3_mixing_metadata = 0;
330  opt->eac3_info_metadata = 0;
331 
332  /* determine mixing metadata / xbsi1 use */
333  if (s->channel_mode > AC3_CHMODE_STEREO && opt->preferred_stereo_downmix != AC3ENC_OPT_NONE) {
334  opt->extended_bsi_1 = 1;
335  opt->eac3_mixing_metadata = 1;
336  }
337  if (s->has_center &&
338  (opt->ltrt_center_mix_level >= 0 || opt->loro_center_mix_level >= 0)) {
339  opt->extended_bsi_1 = 1;
340  opt->eac3_mixing_metadata = 1;
341  }
342  if (s->has_surround &&
343  (opt->ltrt_surround_mix_level >= 0 || opt->loro_surround_mix_level >= 0)) {
344  opt->extended_bsi_1 = 1;
345  opt->eac3_mixing_metadata = 1;
346  }
347 
348  if (s->eac3) {
349  /* determine info metadata use */
351  opt->eac3_info_metadata = 1;
352  if (opt->copyright != AC3ENC_OPT_NONE || opt->original != AC3ENC_OPT_NONE)
353  opt->eac3_info_metadata = 1;
354  if (s->channel_mode == AC3_CHMODE_STEREO &&
356  opt->eac3_info_metadata = 1;
357  if (s->channel_mode >= AC3_CHMODE_2F2R && opt->dolby_surround_ex_mode != AC3ENC_OPT_NONE)
358  opt->eac3_info_metadata = 1;
359  if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE ||
361  opt->audio_production_info = 1;
362  opt->eac3_info_metadata = 1;
363  }
364  } else {
365  /* determine audio production info use */
366  if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE)
367  opt->audio_production_info = 1;
368 
369  /* determine xbsi2 use */
370  if (s->channel_mode >= AC3_CHMODE_2F2R && opt->dolby_surround_ex_mode != AC3ENC_OPT_NONE)
371  opt->extended_bsi_2 = 1;
372  if (s->channel_mode == AC3_CHMODE_STEREO && opt->dolby_headphone_mode != AC3ENC_OPT_NONE)
373  opt->extended_bsi_2 = 1;
375  opt->extended_bsi_2 = 1;
376  }
377 
378  /* validate AC-3 mixing levels */
379  if (!s->eac3) {
380  if (s->has_center) {
381  validate_mix_level(avctx, "center_mix_level", &opt->center_mix_level,
383  &s->center_mix_level);
384  }
385  if (s->has_surround) {
386  validate_mix_level(avctx, "surround_mix_level", &opt->surround_mix_level,
388  &s->surround_mix_level);
389  }
390  }
391 
392  /* validate extended bsi 1 / mixing metadata */
393  if (opt->extended_bsi_1 || opt->eac3_mixing_metadata) {
394  /* default preferred stereo downmix */
397  if (!s->eac3 || s->has_center) {
398  /* validate Lt/Rt center mix level */
399  validate_mix_level(avctx, "ltrt_center_mix_level",
401  EXTMIXLEV_NUM_OPTIONS, 5, 0,
402  &s->ltrt_center_mix_level);
403  /* validate Lo/Ro center mix level */
404  validate_mix_level(avctx, "loro_center_mix_level",
406  EXTMIXLEV_NUM_OPTIONS, 5, 0,
407  &s->loro_center_mix_level);
408  }
409  if (!s->eac3 || s->has_surround) {
410  /* validate Lt/Rt surround mix level */
411  validate_mix_level(avctx, "ltrt_surround_mix_level",
413  EXTMIXLEV_NUM_OPTIONS, 6, 3,
414  &s->ltrt_surround_mix_level);
415  /* validate Lo/Ro surround mix level */
416  validate_mix_level(avctx, "loro_surround_mix_level",
418  EXTMIXLEV_NUM_OPTIONS, 6, 3,
419  &s->loro_surround_mix_level);
420  }
421  }
422 
423  /* validate audio service type / channels combination */
425  avctx->ch_layout.nb_channels == 1) ||
429  && avctx->ch_layout.nb_channels > 1)) {
430  av_log(avctx, AV_LOG_ERROR, "invalid audio service type for the "
431  "specified number of channels\n");
432  return AVERROR(EINVAL);
433  }
434 
435  /* validate extended bsi 2 / info metadata */
436  if (opt->extended_bsi_2 || opt->eac3_info_metadata) {
437  /* default dolby headphone mode */
440  /* default dolby surround ex mode */
443  /* default A/D converter type */
446  }
447 
448  /* copyright & original defaults */
449  if (!s->eac3 || opt->eac3_info_metadata) {
450  /* default copyright */
451  if (opt->copyright == AC3ENC_OPT_NONE)
452  opt->copyright = AC3ENC_OPT_OFF;
453  /* default original */
454  if (opt->original == AC3ENC_OPT_NONE)
455  opt->original = AC3ENC_OPT_ON;
456  }
457 
458  /* dolby surround mode default */
459  if (!s->eac3 || opt->eac3_info_metadata) {
462  }
463 
464  /* validate audio production info */
465  if (opt->audio_production_info) {
466  if (opt->mixing_level == AC3ENC_OPT_NONE) {
467  av_log(avctx, AV_LOG_ERROR, "mixing_level must be set if "
468  "room_type is set\n");
469  return AVERROR(EINVAL);
470  }
471  if (opt->mixing_level < 80) {
472  av_log(avctx, AV_LOG_ERROR, "invalid mixing level. must be between "
473  "80dB and 111dB\n");
474  return AVERROR(EINVAL);
475  }
476  /* default room type */
477  if (opt->room_type == AC3ENC_OPT_NONE)
479  }
480 
481  /* set bitstream id for alternate bitstream syntax */
482  if (!s->eac3 && (opt->extended_bsi_1 || opt->extended_bsi_2))
483  s->bitstream_id = 6;
484 
485  return 0;
486 }
487 
488 /**
489  * Adjust the frame size to make the average bit rate match the target bit rate.
490  * This is only needed for 11025, 22050, and 44100 sample rates or any E-AC-3.
491  *
492  * @param s AC-3 encoder private context
493  */
495 {
496  while (s->bits_written >= s->bit_rate && s->samples_written >= s->sample_rate) {
497  s->bits_written -= s->bit_rate;
498  s->samples_written -= s->sample_rate;
499  }
500  s->frame_size = s->frame_size_min +
501  2 * (s->bits_written * s->sample_rate < s->samples_written * s->bit_rate);
502  s->bits_written += s->frame_size * 8;
503  s->samples_written += AC3_BLOCK_SIZE * s->num_blocks;
504 }
505 
506 /**
507  * Set the initial coupling strategy parameters prior to coupling analysis.
508  *
509  * @param s AC-3 encoder private context
510  */
512 {
513  int blk, ch;
514  int got_cpl_snr;
515  int num_cpl_blocks;
516 
517  /* set coupling use flags for each block/channel */
518  /* TODO: turn coupling on/off and adjust start band based on bit usage */
519  for (blk = 0; blk < s->num_blocks; blk++) {
520  AC3Block *block = &s->blocks[blk];
521  for (ch = 1; ch <= s->fbw_channels; ch++)
522  block->channel_in_cpl[ch] = s->cpl_on;
523  }
524 
525  /* enable coupling for each block if at least 2 channels have coupling
526  enabled for that block */
527  got_cpl_snr = 0;
528  num_cpl_blocks = 0;
529  for (blk = 0; blk < s->num_blocks; blk++) {
530  AC3Block *block = &s->blocks[blk];
531  block->num_cpl_channels = 0;
532  for (ch = 1; ch <= s->fbw_channels; ch++)
533  block->num_cpl_channels += block->channel_in_cpl[ch];
534  block->cpl_in_use = block->num_cpl_channels > 1;
535  num_cpl_blocks += block->cpl_in_use;
536  if (!block->cpl_in_use) {
537  block->num_cpl_channels = 0;
538  for (ch = 1; ch <= s->fbw_channels; ch++)
539  block->channel_in_cpl[ch] = 0;
540  }
541 
542  block->new_cpl_strategy = !blk;
543  if (blk) {
544  for (ch = 1; ch <= s->fbw_channels; ch++) {
545  if (block->channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) {
546  block->new_cpl_strategy = 1;
547  break;
548  }
549  }
550  }
551  block->new_cpl_leak = block->new_cpl_strategy;
552 
553  if (!blk || (block->cpl_in_use && !got_cpl_snr)) {
554  block->new_snr_offsets = 1;
555  if (block->cpl_in_use)
556  got_cpl_snr = 1;
557  } else {
558  block->new_snr_offsets = 0;
559  }
560  }
561  if (!num_cpl_blocks)
562  s->cpl_on = 0;
563 
564  /* set bandwidth for each channel */
565  for (blk = 0; blk < s->num_blocks; blk++) {
566  AC3Block *block = &s->blocks[blk];
567  for (ch = 1; ch <= s->fbw_channels; ch++) {
568  if (block->channel_in_cpl[ch])
569  block->end_freq[ch] = s->start_freq[CPL_CH];
570  else
571  block->end_freq[ch] = s->bandwidth_code * 3 + 73;
572  }
573  }
574 }
575 
576 
577 /**
578  * Apply stereo rematrixing to coefficients based on rematrixing flags.
579  *
580  * @param s AC-3 encoder private context
581  */
583 {
584  int nb_coefs;
585  int blk, bnd, i;
586  int start, end;
587  uint8_t *flags = NULL;
588 
589  if (!s->rematrixing_enabled)
590  return;
591 
592  for (blk = 0; blk < s->num_blocks; blk++) {
593  AC3Block *block = &s->blocks[blk];
594  if (block->new_rematrixing_strategy)
595  flags = block->rematrixing_flags;
596  nb_coefs = FFMIN(block->end_freq[1], block->end_freq[2]);
597  for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++) {
598  if (flags[bnd]) {
599  start = ff_ac3_rematrix_band_tab[bnd];
600  end = FFMIN(nb_coefs, ff_ac3_rematrix_band_tab[bnd+1]);
601  for (i = start; i < end; i++) {
602  int32_t lt = block->fixed_coef[1][i];
603  int32_t rt = block->fixed_coef[2][i];
604  block->fixed_coef[1][i] = (lt + rt) >> 1;
605  block->fixed_coef[2][i] = (lt - rt) >> 1;
606  }
607  }
608  }
609  }
610 }
611 
612 
613 /*
614  * Initialize exponent tables.
615  */
616 static av_cold void exponent_init(void)
617 {
618  int expstr, i, grpsize;
619 
620  for (expstr = EXP_D15-1; expstr <= EXP_D45-1; expstr++) {
621  grpsize = 3 << expstr;
622  for (i = 12; i < 256; i++) {
623  exponent_group_tab[0][expstr][i] = (i + grpsize - 4) / grpsize;
624  exponent_group_tab[1][expstr][i] = (i ) / grpsize;
625  }
626  }
627  /* LFE */
628  exponent_group_tab[0][0][7] = 2;
629 }
630 
631 
632 /*
633  * Extract exponents from the MDCT coefficients.
634  */
636 {
637  int ch = !s->cpl_on;
638  int chan_size = AC3_MAX_COEFS * s->num_blocks * (s->channels - ch + 1);
639  AC3Block *block = &s->blocks[0];
640 
641  s->ac3dsp.extract_exponents(block->exp[ch], block->fixed_coef[ch], chan_size);
642 }
643 
644 
645 /**
646  * Exponent Difference Threshold.
647  * New exponents are sent if their SAD exceed this number.
648  */
649 #define EXP_DIFF_THRESHOLD 500
650 
651 /**
652  * Table used to select exponent strategy based on exponent reuse block interval.
653  */
654 static const uint8_t exp_strategy_reuse_tab[4][6] = {
659 };
660 
661 /*
662  * Calculate exponent strategies for all channels.
663  * Array arrangement is reversed to simplify the per-channel calculation.
664  */
666 {
667  int ch, blk, blk1;
668 
669  for (ch = !s->cpl_on; ch <= s->fbw_channels; ch++) {
670  uint8_t *exp_strategy = s->exp_strategy[ch];
671  uint8_t *exp = s->blocks[0].exp[ch];
672  int exp_diff;
673 
674  /* estimate if the exponent variation & decide if they should be
675  reused in the next frame */
676  exp_strategy[0] = EXP_NEW;
677  exp += AC3_MAX_COEFS;
678  for (blk = 1; blk < s->num_blocks; blk++, exp += AC3_MAX_COEFS) {
679  if (ch == CPL_CH) {
680  if (!s->blocks[blk-1].cpl_in_use) {
681  exp_strategy[blk] = EXP_NEW;
682  continue;
683  } else if (!s->blocks[blk].cpl_in_use) {
684  exp_strategy[blk] = EXP_REUSE;
685  continue;
686  }
687  } else if (s->blocks[blk].channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) {
688  exp_strategy[blk] = EXP_NEW;
689  continue;
690  }
691  exp_diff = s->mecc.sad[0](NULL, exp, exp - AC3_MAX_COEFS, 16, 16);
692  exp_strategy[blk] = EXP_REUSE;
693  if (ch == CPL_CH && exp_diff > (EXP_DIFF_THRESHOLD * (s->blocks[blk].end_freq[ch] - s->start_freq[ch]) / AC3_MAX_COEFS))
694  exp_strategy[blk] = EXP_NEW;
695  else if (ch > CPL_CH && exp_diff > EXP_DIFF_THRESHOLD)
696  exp_strategy[blk] = EXP_NEW;
697  }
698 
699  /* now select the encoding strategy type : if exponents are often
700  recoded, we use a coarse encoding */
701  blk = 0;
702  while (blk < s->num_blocks) {
703  blk1 = blk + 1;
704  while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE)
705  blk1++;
706  exp_strategy[blk] = exp_strategy_reuse_tab[s->num_blks_code][blk1-blk-1];
707  blk = blk1;
708  }
709  }
710  if (s->lfe_on) {
711  ch = s->lfe_channel;
712  s->exp_strategy[ch][0] = EXP_D15;
713  for (blk = 1; blk < s->num_blocks; blk++)
714  s->exp_strategy[ch][blk] = EXP_REUSE;
715  }
716 
717  /* for E-AC-3, determine frame exponent strategy */
718  if (CONFIG_EAC3_ENCODER && s->eac3)
720 }
721 
722 
723 /**
724  * Update the exponents so that they are the ones the decoder will decode.
725  *
726  * @param[in,out] exp array of exponents for 1 block in 1 channel
727  * @param nb_exps number of exponents in active bandwidth
728  * @param exp_strategy exponent strategy for the block
729  * @param cpl indicates if the block is in the coupling channel
730  */
731 static void encode_exponents_blk_ch(uint8_t *exp, int nb_exps, int exp_strategy,
732  int cpl)
733 {
734  int nb_groups, i, k;
735 
736  nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_exps] * 3;
737 
738  /* for each group, compute the minimum exponent */
739  switch(exp_strategy) {
740  case EXP_D25:
741  for (i = 1, k = 1-cpl; i <= nb_groups; i++) {
742  uint8_t exp_min = exp[k];
743  if (exp[k+1] < exp_min)
744  exp_min = exp[k+1];
745  exp[i-cpl] = exp_min;
746  k += 2;
747  }
748  break;
749  case EXP_D45:
750  for (i = 1, k = 1-cpl; i <= nb_groups; i++) {
751  uint8_t exp_min = exp[k];
752  if (exp[k+1] < exp_min)
753  exp_min = exp[k+1];
754  if (exp[k+2] < exp_min)
755  exp_min = exp[k+2];
756  if (exp[k+3] < exp_min)
757  exp_min = exp[k+3];
758  exp[i-cpl] = exp_min;
759  k += 4;
760  }
761  break;
762  }
763 
764  /* constraint for DC exponent */
765  if (!cpl && exp[0] > 15)
766  exp[0] = 15;
767 
768  /* decrease the delta between each groups to within 2 so that they can be
769  differentially encoded */
770  for (i = 1; i <= nb_groups; i++)
771  exp[i] = FFMIN(exp[i], exp[i-1] + 2);
772  i--;
773  while (--i >= 0)
774  exp[i] = FFMIN(exp[i], exp[i+1] + 2);
775 
776  if (cpl)
777  exp[-1] = exp[0] & ~1;
778 
779  /* now we have the exponent values the decoder will see */
780  switch (exp_strategy) {
781  case EXP_D25:
782  for (i = nb_groups, k = (nb_groups * 2)-cpl; i > 0; i--) {
783  uint8_t exp1 = exp[i-cpl];
784  exp[k--] = exp1;
785  exp[k--] = exp1;
786  }
787  break;
788  case EXP_D45:
789  for (i = nb_groups, k = (nb_groups * 4)-cpl; i > 0; i--) {
790  exp[k] = exp[k-1] = exp[k-2] = exp[k-3] = exp[i-cpl];
791  k -= 4;
792  }
793  break;
794  }
795 }
796 
797 
798 /*
799  * Encode exponents from original extracted form to what the decoder will see.
800  * This copies and groups exponents based on exponent strategy and reduces
801  * deltas between adjacent exponent groups so that they can be differentially
802  * encoded.
803  */
805 {
806  int blk, blk1, ch, cpl;
807  uint8_t *exp, *exp_strategy;
808  int nb_coefs, num_reuse_blocks;
809 
810  for (ch = !s->cpl_on; ch <= s->channels; ch++) {
811  exp = s->blocks[0].exp[ch] + s->start_freq[ch];
812  exp_strategy = s->exp_strategy[ch];
813 
814  cpl = (ch == CPL_CH);
815  blk = 0;
816  while (blk < s->num_blocks) {
817  AC3Block *block = &s->blocks[blk];
818  if (cpl && !block->cpl_in_use) {
819  exp += AC3_MAX_COEFS;
820  blk++;
821  continue;
822  }
823  nb_coefs = block->end_freq[ch] - s->start_freq[ch];
824  blk1 = blk + 1;
825 
826  /* count the number of EXP_REUSE blocks after the current block
827  and set exponent reference block numbers */
828  s->exp_ref_block[ch][blk] = blk;
829  while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE) {
830  s->exp_ref_block[ch][blk1] = blk;
831  blk1++;
832  }
833  num_reuse_blocks = blk1 - blk - 1;
834 
835  /* for the EXP_REUSE case we select the min of the exponents */
836  s->ac3dsp.ac3_exponent_min(exp-s->start_freq[ch], num_reuse_blocks,
837  AC3_MAX_COEFS);
838 
839  encode_exponents_blk_ch(exp, nb_coefs, exp_strategy[blk], cpl);
840 
841  exp += AC3_MAX_COEFS * (num_reuse_blocks + 1);
842  blk = blk1;
843  }
844  }
845 
846  /* reference block numbers have been changed, so reset ref_bap_set */
847  s->ref_bap_set = 0;
848 }
849 
850 
851 /*
852  * Count exponent bits based on bandwidth, coupling, and exponent strategies.
853  */
855 {
856  int blk, ch;
857  int nb_groups, bit_count;
858 
859  bit_count = 0;
860  for (blk = 0; blk < s->num_blocks; blk++) {
861  AC3Block *block = &s->blocks[blk];
862  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
863  int exp_strategy = s->exp_strategy[ch][blk];
864  int cpl = (ch == CPL_CH);
865  int nb_coefs = block->end_freq[ch] - s->start_freq[ch];
866 
867  if (exp_strategy == EXP_REUSE)
868  continue;
869 
870  nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_coefs];
871  bit_count += 4 + (nb_groups * 7);
872  }
873  }
874 
875  return bit_count;
876 }
877 
878 
879 /**
880  * Group exponents.
881  * 3 delta-encoded exponents are in each 7-bit group. The number of groups
882  * varies depending on exponent strategy and bandwidth.
883  *
884  * @param s AC-3 encoder private context
885  */
887 {
888  int blk, ch, i, cpl;
889  int group_size, nb_groups;
890  uint8_t *p;
891  int delta0, delta1, delta2;
892  int exp0, exp1;
893 
894  for (blk = 0; blk < s->num_blocks; blk++) {
895  AC3Block *block = &s->blocks[blk];
896  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
897  int exp_strategy = s->exp_strategy[ch][blk];
898  if (exp_strategy == EXP_REUSE)
899  continue;
900  cpl = (ch == CPL_CH);
901  group_size = exp_strategy + (exp_strategy == EXP_D45);
902  nb_groups = exponent_group_tab[cpl][exp_strategy-1][block->end_freq[ch]-s->start_freq[ch]];
903  p = block->exp[ch] + s->start_freq[ch] - cpl;
904 
905  /* DC exponent */
906  exp1 = *p++;
907  block->grouped_exp[ch][0] = exp1;
908 
909  /* remaining exponents are delta encoded */
910  for (i = 1; i <= nb_groups; i++) {
911  /* merge three delta in one code */
912  exp0 = exp1;
913  exp1 = p[0];
914  p += group_size;
915  delta0 = exp1 - exp0 + 2;
916  av_assert2(delta0 >= 0 && delta0 <= 4);
917 
918  exp0 = exp1;
919  exp1 = p[0];
920  p += group_size;
921  delta1 = exp1 - exp0 + 2;
922  av_assert2(delta1 >= 0 && delta1 <= 4);
923 
924  exp0 = exp1;
925  exp1 = p[0];
926  p += group_size;
927  delta2 = exp1 - exp0 + 2;
928  av_assert2(delta2 >= 0 && delta2 <= 4);
929 
930  block->grouped_exp[ch][i] = ((delta0 * 5 + delta1) * 5) + delta2;
931  }
932  }
933  }
934 }
935 
936 
937 /**
938  * Calculate final exponents from the supplied MDCT coefficients and exponent shift.
939  * Extract exponents from MDCT coefficients, calculate exponent strategies,
940  * and encode final exponents.
941  *
942  * @param s AC-3 encoder private context
943  */
945 {
947 
949 
951 
952  emms_c();
953 }
954 
955 
956 /*
957  * Count frame bits that are based solely on fixed parameters.
958  * This only has to be run once when the encoder is initialized.
959  */
961 {
962  static const uint8_t frame_bits_inc[8] = { 0, 0, 2, 2, 2, 4, 2, 4 };
963  int blk;
964  int frame_bits;
965 
966  /* assumptions:
967  * no dynamic range codes
968  * bit allocation parameters do not change between blocks
969  * no delta bit allocation
970  * no skipped data
971  * no auxiliary data
972  * no E-AC-3 metadata
973  */
974 
975  /* header */
976  frame_bits = 16; /* sync info */
977  if (s->eac3) {
978  /* bitstream info header */
979  frame_bits += 35;
980  frame_bits += 1 + 1;
981  if (s->num_blocks != 0x6)
982  frame_bits++;
983  frame_bits++;
984  /* audio frame header */
985  if (s->num_blocks == 6)
986  frame_bits += 2;
987  frame_bits += 10;
988  /* exponent strategy */
989  if (s->use_frame_exp_strategy)
990  frame_bits += 5 * s->fbw_channels;
991  else
992  frame_bits += s->num_blocks * 2 * s->fbw_channels;
993  if (s->lfe_on)
994  frame_bits += s->num_blocks;
995  /* converter exponent strategy */
996  if (s->num_blks_code != 0x3)
997  frame_bits++;
998  else
999  frame_bits += s->fbw_channels * 5;
1000  /* snr offsets */
1001  frame_bits += 10;
1002  /* block start info */
1003  if (s->num_blocks != 1)
1004  frame_bits++;
1005  } else {
1006  frame_bits += 49;
1007  frame_bits += frame_bits_inc[s->channel_mode];
1008  }
1009 
1010  /* audio blocks */
1011  for (blk = 0; blk < s->num_blocks; blk++) {
1012  if (!s->eac3) {
1013  /* block switch flags */
1014  frame_bits += s->fbw_channels;
1015 
1016  /* dither flags */
1017  frame_bits += s->fbw_channels;
1018  }
1019 
1020  /* dynamic range */
1021  frame_bits++;
1022 
1023  /* spectral extension */
1024  if (s->eac3)
1025  frame_bits++;
1026 
1027  /* coupling strategy exists: cplstre */
1028  if (!s->eac3)
1029  frame_bits++;
1030 
1031  if (!s->eac3) {
1032  /* exponent strategy */
1033  frame_bits += 2 * s->fbw_channels;
1034  if (s->lfe_on)
1035  frame_bits++;
1036 
1037  /* bit allocation params */
1038  frame_bits++;
1039  if (!blk)
1040  frame_bits += 2 + 2 + 2 + 2 + 3;
1041  }
1042 
1043  /* snroffste for AC-3, convsnroffste for E-AC-3 */
1044  frame_bits++;
1045 
1046  if (!s->eac3) {
1047  /* delta bit allocation */
1048  frame_bits++;
1049 
1050  /* skipped data */
1051  frame_bits++;
1052  }
1053  }
1054 
1055  /* auxiliary data */
1056  frame_bits++;
1057 
1058  /* CRC */
1059  frame_bits += 1 + 16;
1060 
1061  s->frame_bits_fixed = frame_bits;
1062 }
1063 
1064 
1065 /*
1066  * Initialize bit allocation.
1067  * Set default parameter codes and calculate parameter values.
1068  */
1070 {
1071  int ch;
1072 
1073  /* init default parameters */
1074  s->slow_decay_code = 2;
1075  s->fast_decay_code = 1;
1076  s->slow_gain_code = 1;
1077  s->db_per_bit_code = s->eac3 ? 2 : 3;
1078  s->floor_code = 7;
1079  for (ch = 0; ch <= s->channels; ch++)
1080  s->fast_gain_code[ch] = 4;
1081 
1082  /* initial snr offset */
1083  s->coarse_snr_offset = 40;
1084 
1085  /* compute real values */
1086  /* currently none of these values change during encoding, so we can just
1087  set them once at initialization */
1088  s->bit_alloc.slow_decay = ff_ac3_slow_decay_tab[s->slow_decay_code];
1089  s->bit_alloc.fast_decay = ff_ac3_fast_decay_tab[s->fast_decay_code];
1090  s->bit_alloc.slow_gain = ff_ac3_slow_gain_tab[s->slow_gain_code];
1091  s->bit_alloc.db_per_bit = ff_ac3_db_per_bit_tab[s->db_per_bit_code];
1092  s->bit_alloc.floor = ff_ac3_floor_tab[s->floor_code];
1093  s->bit_alloc.cpl_fast_leak = 0;
1094  s->bit_alloc.cpl_slow_leak = 0;
1095 
1097 }
1098 
1099 
1100 /*
1101  * Count the bits used to encode the frame, minus exponents and mantissas.
1102  * Bits based on fixed parameters have already been counted, so now we just
1103  * have to add the bits based on parameters that change during encoding.
1104  */
1106 {
1107  AC3EncOptions *opt = &s->options;
1108  int blk, ch;
1109  int frame_bits = 0;
1110 
1111  /* header */
1112  if (s->eac3) {
1113  if (opt->eac3_mixing_metadata) {
1114  if (s->channel_mode > AC3_CHMODE_STEREO)
1115  frame_bits += 2;
1116  if (s->has_center)
1117  frame_bits += 6;
1118  if (s->has_surround)
1119  frame_bits += 6;
1120  frame_bits += s->lfe_on;
1121  frame_bits += 1 + 1 + 2;
1122  if (s->channel_mode < AC3_CHMODE_STEREO)
1123  frame_bits++;
1124  frame_bits++;
1125  }
1126  if (opt->eac3_info_metadata) {
1127  frame_bits += 3 + 1 + 1;
1128  if (s->channel_mode == AC3_CHMODE_STEREO)
1129  frame_bits += 2 + 2;
1130  if (s->channel_mode >= AC3_CHMODE_2F2R)
1131  frame_bits += 2;
1132  frame_bits++;
1133  if (opt->audio_production_info)
1134  frame_bits += 5 + 2 + 1;
1135  frame_bits++;
1136  }
1137  /* coupling */
1138  if (s->channel_mode > AC3_CHMODE_MONO) {
1139  frame_bits++;
1140  for (blk = 1; blk < s->num_blocks; blk++) {
1141  AC3Block *block = &s->blocks[blk];
1142  frame_bits++;
1143  if (block->new_cpl_strategy)
1144  frame_bits++;
1145  }
1146  }
1147  /* coupling exponent strategy */
1148  if (s->cpl_on) {
1149  if (s->use_frame_exp_strategy) {
1150  frame_bits += 5;
1151  } else {
1152  for (blk = 0; blk < s->num_blocks; blk++)
1153  frame_bits += 2 * s->blocks[blk].cpl_in_use;
1154  }
1155  }
1156  } else {
1157  if (opt->audio_production_info)
1158  frame_bits += 7;
1159  if (s->bitstream_id == 6) {
1160  if (opt->extended_bsi_1)
1161  frame_bits += 14;
1162  if (opt->extended_bsi_2)
1163  frame_bits += 14;
1164  }
1165  }
1166 
1167  /* audio blocks */
1168  for (blk = 0; blk < s->num_blocks; blk++) {
1169  AC3Block *block = &s->blocks[blk];
1170 
1171  /* coupling strategy */
1172  if (block->new_cpl_strategy) {
1173  if (!s->eac3)
1174  frame_bits++;
1175  if (block->cpl_in_use) {
1176  if (s->eac3)
1177  frame_bits++;
1178  if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO)
1179  frame_bits += s->fbw_channels;
1180  if (s->channel_mode == AC3_CHMODE_STEREO)
1181  frame_bits++;
1182  frame_bits += 4 + 4;
1183  if (s->eac3)
1184  frame_bits++;
1185  else
1186  frame_bits += s->num_cpl_subbands - 1;
1187  }
1188  }
1189 
1190  /* coupling coordinates */
1191  if (block->cpl_in_use) {
1192  for (ch = 1; ch <= s->fbw_channels; ch++) {
1193  if (block->channel_in_cpl[ch]) {
1194  if (!s->eac3 || block->new_cpl_coords[ch] != 2)
1195  frame_bits++;
1196  if (block->new_cpl_coords[ch]) {
1197  frame_bits += 2;
1198  frame_bits += (4 + 4) * s->num_cpl_bands;
1199  }
1200  }
1201  }
1202  }
1203 
1204  /* stereo rematrixing */
1205  if (s->channel_mode == AC3_CHMODE_STEREO) {
1206  if (!s->eac3 || blk > 0)
1207  frame_bits++;
1208  if (s->blocks[blk].new_rematrixing_strategy)
1209  frame_bits += block->num_rematrixing_bands;
1210  }
1211 
1212  /* bandwidth codes & gain range */
1213  for (ch = 1; ch <= s->fbw_channels; ch++) {
1214  if (s->exp_strategy[ch][blk] != EXP_REUSE) {
1215  if (!block->channel_in_cpl[ch])
1216  frame_bits += 6;
1217  frame_bits += 2;
1218  }
1219  }
1220 
1221  /* coupling exponent strategy */
1222  if (!s->eac3 && block->cpl_in_use)
1223  frame_bits += 2;
1224 
1225  /* snr offsets and fast gain codes */
1226  if (!s->eac3) {
1227  if (block->new_snr_offsets)
1228  frame_bits += 6 + (s->channels + block->cpl_in_use) * (4 + 3);
1229  }
1230 
1231  /* coupling leak info */
1232  if (block->cpl_in_use) {
1233  if (!s->eac3 || block->new_cpl_leak != 2)
1234  frame_bits++;
1235  if (block->new_cpl_leak)
1236  frame_bits += 3 + 3;
1237  }
1238  }
1239 
1240  s->frame_bits = s->frame_bits_fixed + frame_bits;
1241 }
1242 
1243 
1244 /*
1245  * Calculate masking curve based on the final exponents.
1246  * Also calculate the power spectral densities to use in future calculations.
1247  */
1249 {
1250  int blk, ch;
1251 
1252  for (blk = 0; blk < s->num_blocks; blk++) {
1253  AC3Block *block = &s->blocks[blk];
1254  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1255  /* We only need psd and mask for calculating bap.
1256  Since we currently do not calculate bap when exponent
1257  strategy is EXP_REUSE we do not need to calculate psd or mask. */
1258  if (s->exp_strategy[ch][blk] != EXP_REUSE) {
1259  ff_ac3_bit_alloc_calc_psd(block->exp[ch], s->start_freq[ch],
1260  block->end_freq[ch], block->psd[ch],
1261  block->band_psd[ch]);
1262  ff_ac3_bit_alloc_calc_mask(&s->bit_alloc, block->band_psd[ch],
1263  s->start_freq[ch], block->end_freq[ch],
1264  ff_ac3_fast_gain_tab[s->fast_gain_code[ch]],
1265  ch == s->lfe_channel,
1266  DBA_NONE, 0, NULL, NULL, NULL,
1267  block->mask[ch]);
1268  }
1269  }
1270  }
1271 }
1272 
1273 
1274 /*
1275  * Ensure that bap for each block and channel point to the current bap_buffer.
1276  * They may have been switched during the bit allocation search.
1277  */
1279 {
1280  int blk, ch;
1281  uint8_t *ref_bap;
1282 
1283  if (s->ref_bap[0][0] == s->bap_buffer && s->ref_bap_set)
1284  return;
1285 
1286  ref_bap = s->bap_buffer;
1287  for (ch = 0; ch <= s->channels; ch++) {
1288  for (blk = 0; blk < s->num_blocks; blk++)
1289  s->ref_bap[ch][blk] = ref_bap + AC3_MAX_COEFS * s->exp_ref_block[ch][blk];
1290  ref_bap += AC3_MAX_COEFS * s->num_blocks;
1291  }
1292  s->ref_bap_set = 1;
1293 }
1294 
1295 
1296 /**
1297  * Initialize mantissa counts.
1298  * These are set so that they are padded to the next whole group size when bits
1299  * are counted in compute_mantissa_size.
1300  *
1301  * @param[in,out] mant_cnt running counts for each bap value for each block
1302  */
1303 static void count_mantissa_bits_init(uint16_t mant_cnt[AC3_MAX_BLOCKS][16])
1304 {
1305  int blk;
1306 
1307  for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
1308  memset(mant_cnt[blk], 0, sizeof(mant_cnt[blk]));
1309  mant_cnt[blk][1] = mant_cnt[blk][2] = 2;
1310  mant_cnt[blk][4] = 1;
1311  }
1312 }
1313 
1314 
1315 /**
1316  * Update mantissa bit counts for all blocks in 1 channel in a given bandwidth
1317  * range.
1318  *
1319  * @param s AC-3 encoder private context
1320  * @param ch channel index
1321  * @param[in,out] mant_cnt running counts for each bap value for each block
1322  * @param start starting coefficient bin
1323  * @param end ending coefficient bin
1324  */
1326  uint16_t mant_cnt[AC3_MAX_BLOCKS][16],
1327  int start, int end)
1328 {
1329  int blk;
1330 
1331  for (blk = 0; blk < s->num_blocks; blk++) {
1332  AC3Block *block = &s->blocks[blk];
1333  if (ch == CPL_CH && !block->cpl_in_use)
1334  continue;
1335  s->ac3dsp.update_bap_counts(mant_cnt[blk],
1336  s->ref_bap[ch][blk] + start,
1337  FFMIN(end, block->end_freq[ch]) - start);
1338  }
1339 }
1340 
1341 
1342 /*
1343  * Count the number of mantissa bits in the frame based on the bap values.
1344  */
1346 {
1347  int ch, max_end_freq;
1348  LOCAL_ALIGNED_16(uint16_t, mant_cnt, [AC3_MAX_BLOCKS], [16]);
1349 
1350  count_mantissa_bits_init(mant_cnt);
1351 
1352  max_end_freq = s->bandwidth_code * 3 + 73;
1353  for (ch = !s->cpl_enabled; ch <= s->channels; ch++)
1354  count_mantissa_bits_update_ch(s, ch, mant_cnt, s->start_freq[ch],
1355  max_end_freq);
1356 
1357  return s->ac3dsp.compute_mantissa_size(mant_cnt);
1358 }
1359 
1360 
1361 /**
1362  * Run the bit allocation with a given SNR offset.
1363  * This calculates the bit allocation pointers that will be used to determine
1364  * the quantization of each mantissa.
1365  *
1366  * @param s AC-3 encoder private context
1367  * @param snr_offset SNR offset, 0 to 1023
1368  * @return the number of bits needed for mantissas if the given SNR offset is
1369  * is used.
1370  */
1371 static int bit_alloc(AC3EncodeContext *s, int snr_offset)
1372 {
1373  int blk, ch;
1374 
1375  snr_offset = (snr_offset - 240) * 4;
1376 
1377  reset_block_bap(s);
1378  for (blk = 0; blk < s->num_blocks; blk++) {
1379  AC3Block *block = &s->blocks[blk];
1380 
1381  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1382  /* Currently the only bit allocation parameters which vary across
1383  blocks within a frame are the exponent values. We can take
1384  advantage of that by reusing the bit allocation pointers
1385  whenever we reuse exponents. */
1386  if (s->exp_strategy[ch][blk] != EXP_REUSE) {
1387  s->ac3dsp.bit_alloc_calc_bap(block->mask[ch], block->psd[ch],
1388  s->start_freq[ch], block->end_freq[ch],
1389  snr_offset, s->bit_alloc.floor,
1390  ff_ac3_bap_tab, s->ref_bap[ch][blk]);
1391  }
1392  }
1393  }
1394  return count_mantissa_bits(s);
1395 }
1396 
1397 
1398 /*
1399  * Constant bitrate bit allocation search.
1400  * Find the largest SNR offset that will allow data to fit in the frame.
1401  */
1403 {
1404  int ch;
1405  int bits_left;
1406  int snr_offset, snr_incr;
1407 
1408  bits_left = 8 * s->frame_size - (s->frame_bits + s->exponent_bits);
1409  if (bits_left < 0)
1410  return AVERROR(EINVAL);
1411 
1412  snr_offset = s->coarse_snr_offset << 4;
1413 
1414  /* if previous frame SNR offset was 1023, check if current frame can also
1415  use SNR offset of 1023. if so, skip the search. */
1416  if ((snr_offset | s->fine_snr_offset[1]) == 1023) {
1417  if (bit_alloc(s, 1023) <= bits_left)
1418  return 0;
1419  }
1420 
1421  while (snr_offset >= 0 &&
1422  bit_alloc(s, snr_offset) > bits_left) {
1423  snr_offset -= 64;
1424  }
1425  if (snr_offset < 0)
1426  return AVERROR(EINVAL);
1427 
1428  FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1429  for (snr_incr = 64; snr_incr > 0; snr_incr >>= 2) {
1430  while (snr_offset + snr_incr <= 1023 &&
1431  bit_alloc(s, snr_offset + snr_incr) <= bits_left) {
1432  snr_offset += snr_incr;
1433  FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1434  }
1435  }
1436  FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1437  reset_block_bap(s);
1438 
1439  s->coarse_snr_offset = snr_offset >> 4;
1440  for (ch = !s->cpl_on; ch <= s->channels; ch++)
1441  s->fine_snr_offset[ch] = snr_offset & 0xF;
1442 
1443  return 0;
1444 }
1445 
1446 
1447 /*
1448  * Perform bit allocation search.
1449  * Finds the SNR offset value that maximizes quality and fits in the specified
1450  * frame size. Output is the SNR offset and a set of bit allocation pointers
1451  * used to quantize the mantissas.
1452  */
1454 {
1456 
1457  s->exponent_bits = count_exponent_bits(s);
1458 
1460 
1461  return cbr_bit_allocation(s);
1462 }
1463 
1464 
1465 /**
1466  * Symmetric quantization on 'levels' levels.
1467  *
1468  * @param c unquantized coefficient
1469  * @param e exponent
1470  * @param levels number of quantization levels
1471  * @return quantized coefficient
1472  */
1473 static inline int sym_quant(int c, int e, int levels)
1474 {
1475  int v = (((levels * c) >> (24 - e)) + levels) >> 1;
1476  av_assert2(v >= 0 && v < levels);
1477  return v;
1478 }
1479 
1480 
1481 /**
1482  * Asymmetric quantization on 2^qbits levels.
1483  *
1484  * @param c unquantized coefficient
1485  * @param e exponent
1486  * @param qbits number of quantization bits
1487  * @return quantized coefficient
1488  */
1489 static inline int asym_quant(int c, int e, int qbits)
1490 {
1491  int m;
1492 
1493  c = (((c * (1<<e)) >> (24 - qbits)) + 1) >> 1;
1494  m = (1 << (qbits-1));
1495  if (c >= m)
1496  c = m - 1;
1497  av_assert2(c >= -m);
1498  return c;
1499 }
1500 
1501 
1502 /**
1503  * Quantize a set of mantissas for a single channel in a single block.
1504  *
1505  * @param s Mantissa count context
1506  * @param fixed_coef unquantized fixed-point coefficients
1507  * @param exp exponents
1508  * @param bap bit allocation pointer indices
1509  * @param[out] qmant quantized coefficients
1510  * @param start_freq starting coefficient bin
1511  * @param end_freq ending coefficient bin
1512  */
1513 static void quantize_mantissas_blk_ch(AC3Mant *s, int32_t *fixed_coef,
1514  uint8_t *exp, uint8_t *bap,
1515  int16_t *qmant, int start_freq,
1516  int end_freq)
1517 {
1518  int i;
1519 
1520  for (i = start_freq; i < end_freq; i++) {
1521  int c = fixed_coef[i];
1522  int e = exp[i];
1523  int v = bap[i];
1524  switch (v) {
1525  case 0:
1526  break;
1527  case 1:
1528  v = sym_quant(c, e, 3);
1529  switch (s->mant1_cnt) {
1530  case 0:
1531  s->qmant1_ptr = &qmant[i];
1532  v = 9 * v;
1533  s->mant1_cnt = 1;
1534  break;
1535  case 1:
1536  *s->qmant1_ptr += 3 * v;
1537  s->mant1_cnt = 2;
1538  v = 128;
1539  break;
1540  default:
1541  *s->qmant1_ptr += v;
1542  s->mant1_cnt = 0;
1543  v = 128;
1544  break;
1545  }
1546  break;
1547  case 2:
1548  v = sym_quant(c, e, 5);
1549  switch (s->mant2_cnt) {
1550  case 0:
1551  s->qmant2_ptr = &qmant[i];
1552  v = 25 * v;
1553  s->mant2_cnt = 1;
1554  break;
1555  case 1:
1556  *s->qmant2_ptr += 5 * v;
1557  s->mant2_cnt = 2;
1558  v = 128;
1559  break;
1560  default:
1561  *s->qmant2_ptr += v;
1562  s->mant2_cnt = 0;
1563  v = 128;
1564  break;
1565  }
1566  break;
1567  case 3:
1568  v = sym_quant(c, e, 7);
1569  break;
1570  case 4:
1571  v = sym_quant(c, e, 11);
1572  switch (s->mant4_cnt) {
1573  case 0:
1574  s->qmant4_ptr = &qmant[i];
1575  v = 11 * v;
1576  s->mant4_cnt = 1;
1577  break;
1578  default:
1579  *s->qmant4_ptr += v;
1580  s->mant4_cnt = 0;
1581  v = 128;
1582  break;
1583  }
1584  break;
1585  case 5:
1586  v = sym_quant(c, e, 15);
1587  break;
1588  case 14:
1589  v = asym_quant(c, e, 14);
1590  break;
1591  case 15:
1592  v = asym_quant(c, e, 16);
1593  break;
1594  default:
1595  v = asym_quant(c, e, v - 1);
1596  break;
1597  }
1598  qmant[i] = v;
1599  }
1600 }
1601 
1602 
1603 /**
1604  * Quantize mantissas using coefficients, exponents, and bit allocation pointers.
1605  *
1606  * @param s AC-3 encoder private context
1607  */
1609 {
1610  int blk, ch, ch0=0, got_cpl;
1611 
1612  for (blk = 0; blk < s->num_blocks; blk++) {
1613  AC3Block *block = &s->blocks[blk];
1614  AC3Mant m = { 0 };
1615 
1616  got_cpl = !block->cpl_in_use;
1617  for (ch = 1; ch <= s->channels; ch++) {
1618  if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) {
1619  ch0 = ch - 1;
1620  ch = CPL_CH;
1621  got_cpl = 1;
1622  }
1623  quantize_mantissas_blk_ch(&m, block->fixed_coef[ch],
1624  s->blocks[s->exp_ref_block[ch][blk]].exp[ch],
1625  s->ref_bap[ch][blk], block->qmant[ch],
1626  s->start_freq[ch], block->end_freq[ch]);
1627  if (ch == CPL_CH)
1628  ch = ch0;
1629  }
1630  }
1631 }
1632 
1633 
1634 /*
1635  * Write the AC-3 frame header to the output bitstream.
1636  */
1638 {
1639  AC3EncOptions *opt = &s->options;
1640 
1641  put_bits(pb, 16, 0x0b77); /* frame header */
1642  put_bits(pb, 16, 0); /* crc1: will be filled later */
1643  put_bits(pb, 2, s->bit_alloc.sr_code);
1644  put_bits(pb, 6, s->frame_size_code + (s->frame_size - s->frame_size_min) / 2);
1645  put_bits(pb, 5, s->bitstream_id);
1646  put_bits(pb, 3, s->bitstream_mode);
1647  put_bits(pb, 3, s->channel_mode);
1648  if ((s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO)
1649  put_bits(pb, 2, s->center_mix_level);
1650  if (s->channel_mode & 0x04)
1651  put_bits(pb, 2, s->surround_mix_level);
1652  if (s->channel_mode == AC3_CHMODE_STEREO)
1653  put_bits(pb, 2, opt->dolby_surround_mode);
1654  put_bits(pb, 1, s->lfe_on); /* LFE */
1655  put_bits(pb, 5, -opt->dialogue_level);
1656  put_bits(pb, 1, 0); /* no compression control word */
1657  put_bits(pb, 1, 0); /* no lang code */
1658  put_bits(pb, 1, opt->audio_production_info);
1659  if (opt->audio_production_info) {
1660  put_bits(pb, 5, opt->mixing_level - 80);
1661  put_bits(pb, 2, opt->room_type);
1662  }
1663  put_bits(pb, 1, opt->copyright);
1664  put_bits(pb, 1, opt->original);
1665  if (s->bitstream_id == 6) {
1666  /* alternate bit stream syntax */
1667  put_bits(pb, 1, opt->extended_bsi_1);
1668  if (opt->extended_bsi_1) {
1669  put_bits(pb, 2, opt->preferred_stereo_downmix);
1670  put_bits(pb, 3, s->ltrt_center_mix_level);
1671  put_bits(pb, 3, s->ltrt_surround_mix_level);
1672  put_bits(pb, 3, s->loro_center_mix_level);
1673  put_bits(pb, 3, s->loro_surround_mix_level);
1674  }
1675  put_bits(pb, 1, opt->extended_bsi_2);
1676  if (opt->extended_bsi_2) {
1677  put_bits(pb, 2, opt->dolby_surround_ex_mode);
1678  put_bits(pb, 2, opt->dolby_headphone_mode);
1679  put_bits(pb, 1, opt->ad_converter_type);
1680  put_bits(pb, 9, 0); /* xbsi2 and encinfo : reserved */
1681  }
1682  } else {
1683  put_bits(pb, 1, 0); /* no time code 1 */
1684  put_bits(pb, 1, 0); /* no time code 2 */
1685  }
1686  put_bits(pb, 1, 0); /* no additional bit stream info */
1687 }
1688 
1689 
1690 /*
1691  * Write one audio block to the output bitstream.
1692  */
1694 {
1695  int ch, i, baie, bnd, got_cpl, av_uninit(ch0);
1696  AC3Block *block = &s->blocks[blk];
1697 
1698  /* block switching */
1699  if (!s->eac3) {
1700  for (ch = 0; ch < s->fbw_channels; ch++)
1701  put_bits(pb, 1, 0);
1702  }
1703 
1704  /* dither flags */
1705  if (!s->eac3) {
1706  for (ch = 0; ch < s->fbw_channels; ch++)
1707  put_bits(pb, 1, 1);
1708  }
1709 
1710  /* dynamic range codes */
1711  put_bits(pb, 1, 0);
1712 
1713  /* spectral extension */
1714  if (s->eac3)
1715  put_bits(pb, 1, 0);
1716 
1717  /* channel coupling */
1718  if (!s->eac3)
1719  put_bits(pb, 1, block->new_cpl_strategy);
1720  if (block->new_cpl_strategy) {
1721  if (!s->eac3)
1722  put_bits(pb, 1, block->cpl_in_use);
1723  if (block->cpl_in_use) {
1724  int start_sub, end_sub;
1725  if (s->eac3)
1726  put_bits(pb, 1, 0); /* enhanced coupling */
1727  if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO) {
1728  for (ch = 1; ch <= s->fbw_channels; ch++)
1729  put_bits(pb, 1, block->channel_in_cpl[ch]);
1730  }
1731  if (s->channel_mode == AC3_CHMODE_STEREO)
1732  put_bits(pb, 1, 0); /* phase flags in use */
1733  start_sub = (s->start_freq[CPL_CH] - 37) / 12;
1734  end_sub = (s->cpl_end_freq - 37) / 12;
1735  put_bits(pb, 4, start_sub);
1736  put_bits(pb, 4, end_sub - 3);
1737  /* coupling band structure */
1738  if (s->eac3) {
1739  put_bits(pb, 1, 0); /* use default */
1740  } else {
1741  for (bnd = start_sub+1; bnd < end_sub; bnd++)
1743  }
1744  }
1745  }
1746 
1747  /* coupling coordinates */
1748  if (block->cpl_in_use) {
1749  for (ch = 1; ch <= s->fbw_channels; ch++) {
1750  if (block->channel_in_cpl[ch]) {
1751  if (!s->eac3 || block->new_cpl_coords[ch] != 2)
1752  put_bits(pb, 1, block->new_cpl_coords[ch]);
1753  if (block->new_cpl_coords[ch]) {
1754  put_bits(pb, 2, block->cpl_master_exp[ch]);
1755  for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
1756  put_bits(pb, 4, block->cpl_coord_exp [ch][bnd]);
1757  put_bits(pb, 4, block->cpl_coord_mant[ch][bnd]);
1758  }
1759  }
1760  }
1761  }
1762  }
1763 
1764  /* stereo rematrixing */
1765  if (s->channel_mode == AC3_CHMODE_STEREO) {
1766  if (!s->eac3 || blk > 0)
1767  put_bits(pb, 1, block->new_rematrixing_strategy);
1768  if (block->new_rematrixing_strategy) {
1769  /* rematrixing flags */
1770  for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++)
1771  put_bits(pb, 1, block->rematrixing_flags[bnd]);
1772  }
1773  }
1774 
1775  /* exponent strategy */
1776  if (!s->eac3) {
1777  for (ch = !block->cpl_in_use; ch <= s->fbw_channels; ch++)
1778  put_bits(pb, 2, s->exp_strategy[ch][blk]);
1779  if (s->lfe_on)
1780  put_bits(pb, 1, s->exp_strategy[s->lfe_channel][blk]);
1781  }
1782 
1783  /* bandwidth */
1784  for (ch = 1; ch <= s->fbw_channels; ch++) {
1785  if (s->exp_strategy[ch][blk] != EXP_REUSE && !block->channel_in_cpl[ch])
1786  put_bits(pb, 6, s->bandwidth_code);
1787  }
1788 
1789  /* exponents */
1790  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1791  int nb_groups;
1792  int cpl = (ch == CPL_CH);
1793 
1794  if (s->exp_strategy[ch][blk] == EXP_REUSE)
1795  continue;
1796 
1797  /* DC exponent */
1798  put_bits(pb, 4, block->grouped_exp[ch][0] >> cpl);
1799 
1800  /* exponent groups */
1801  nb_groups = exponent_group_tab[cpl][s->exp_strategy[ch][blk]-1][block->end_freq[ch]-s->start_freq[ch]];
1802  for (i = 1; i <= nb_groups; i++)
1803  put_bits(pb, 7, block->grouped_exp[ch][i]);
1804 
1805  /* gain range info */
1806  if (ch != s->lfe_channel && !cpl)
1807  put_bits(pb, 2, 0);
1808  }
1809 
1810  /* bit allocation info */
1811  if (!s->eac3) {
1812  baie = (blk == 0);
1813  put_bits(pb, 1, baie);
1814  if (baie) {
1815  put_bits(pb, 2, s->slow_decay_code);
1816  put_bits(pb, 2, s->fast_decay_code);
1817  put_bits(pb, 2, s->slow_gain_code);
1818  put_bits(pb, 2, s->db_per_bit_code);
1819  put_bits(pb, 3, s->floor_code);
1820  }
1821  }
1822 
1823  /* snr offset */
1824  if (!s->eac3) {
1825  put_bits(pb, 1, block->new_snr_offsets);
1826  if (block->new_snr_offsets) {
1827  put_bits(pb, 6, s->coarse_snr_offset);
1828  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1829  put_bits(pb, 4, s->fine_snr_offset[ch]);
1830  put_bits(pb, 3, s->fast_gain_code[ch]);
1831  }
1832  }
1833  } else {
1834  put_bits(pb, 1, 0); /* no converter snr offset */
1835  }
1836 
1837  /* coupling leak */
1838  if (block->cpl_in_use) {
1839  if (!s->eac3 || block->new_cpl_leak != 2)
1840  put_bits(pb, 1, block->new_cpl_leak);
1841  if (block->new_cpl_leak) {
1842  put_bits(pb, 3, s->bit_alloc.cpl_fast_leak);
1843  put_bits(pb, 3, s->bit_alloc.cpl_slow_leak);
1844  }
1845  }
1846 
1847  if (!s->eac3) {
1848  put_bits(pb, 1, 0); /* no delta bit allocation */
1849  put_bits(pb, 1, 0); /* no data to skip */
1850  }
1851 
1852  /* mantissas */
1853  got_cpl = !block->cpl_in_use;
1854  for (ch = 1; ch <= s->channels; ch++) {
1855  int b, q;
1856 
1857  if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) {
1858  ch0 = ch - 1;
1859  ch = CPL_CH;
1860  got_cpl = 1;
1861  }
1862  for (i = s->start_freq[ch]; i < block->end_freq[ch]; i++) {
1863  q = block->qmant[ch][i];
1864  b = s->ref_bap[ch][blk][i];
1865  switch (b) {
1866  case 0: break;
1867  case 1: if (q != 128) put_bits (pb, 5, q); break;
1868  case 2: if (q != 128) put_bits (pb, 7, q); break;
1869  case 3: put_sbits(pb, 3, q); break;
1870  case 4: if (q != 128) put_bits (pb, 7, q); break;
1871  case 14: put_sbits(pb, 14, q); break;
1872  case 15: put_sbits(pb, 16, q); break;
1873  default: put_sbits(pb, b-1, q); break;
1874  }
1875  }
1876  if (ch == CPL_CH)
1877  ch = ch0;
1878  }
1879 }
1880 
1881 
1882 /** CRC-16 Polynomial */
1883 #define CRC16_POLY ((1 << 0) | (1 << 2) | (1 << 15) | (1 << 16))
1884 
1885 
1886 static unsigned int mul_poly(unsigned int a, unsigned int b, unsigned int poly)
1887 {
1888  unsigned int c;
1889 
1890  c = 0;
1891  while (a) {
1892  if (a & 1)
1893  c ^= b;
1894  a = a >> 1;
1895  b = b << 1;
1896  if (b & (1 << 16))
1897  b ^= poly;
1898  }
1899  return c;
1900 }
1901 
1902 
1903 static unsigned int pow_poly(unsigned int a, unsigned int n, unsigned int poly)
1904 {
1905  unsigned int r;
1906  r = 1;
1907  while (n) {
1908  if (n & 1)
1909  r = mul_poly(r, a, poly);
1910  a = mul_poly(a, a, poly);
1911  n >>= 1;
1912  }
1913  return r;
1914 }
1915 
1916 
1917 /*
1918  * Fill the end of the frame with 0's and compute the two CRCs.
1919  */
1921 {
1922  const AVCRC *crc_ctx = av_crc_get_table(AV_CRC_16_ANSI);
1923  int frame_size_58, pad_bytes, crc1, crc2, crc_inv;
1924  uint8_t *frame;
1925 
1926  frame_size_58 = ((s->frame_size >> 2) + (s->frame_size >> 4)) << 1;
1927 
1928  /* pad the remainder of the frame with zeros */
1929  av_assert2(s->frame_size * 8 - put_bits_count(pb) >= 18);
1930  flush_put_bits(pb);
1931  frame = pb->buf;
1932  pad_bytes = s->frame_size - (put_bits_ptr(pb) - frame) - 2;
1933  av_assert2(pad_bytes >= 0);
1934  if (pad_bytes > 0)
1935  memset(put_bits_ptr(pb), 0, pad_bytes);
1936 
1937  if (s->eac3) {
1938  /* compute crc2 */
1939  crc2 = av_crc(crc_ctx, 0, frame + 2, s->frame_size - 4);
1940  } else {
1941  /* compute crc1 */
1942  /* this is not so easy because it is at the beginning of the data... */
1943  crc1 = av_bswap16(av_crc(crc_ctx, 0, frame + 4, frame_size_58 - 4));
1944  crc_inv = s->crc_inv[s->frame_size > s->frame_size_min];
1945  crc1 = mul_poly(crc_inv, crc1, CRC16_POLY);
1946  AV_WB16(frame + 2, crc1);
1947 
1948  /* compute crc2 */
1949  crc2 = av_crc(crc_ctx, 0, frame + frame_size_58,
1950  s->frame_size - frame_size_58 - 2);
1951  }
1952  crc2 = av_bswap16(crc2);
1953  /* ensure crc2 does not match sync word by flipping crcrsv bit if needed */
1954  if (crc2 == 0x0B77) {
1955  /* The CRC generator polynomial is x^16 + x^15 + x^2 + 1,
1956  * so xor'ing with 0x18005 does not affect the CRC. */
1957  frame[s->frame_size - 3] ^= 0x1;
1958  crc2 ^= 0x8005;
1959  }
1960  AV_WB16(frame + s->frame_size - 2, crc2);
1961 }
1962 
1963 
1964 /**
1965  * Write the frame to the output bitstream.
1966  *
1967  * @param s AC-3 encoder private context
1968  * @param frame output data buffer
1969  */
1970 static void ac3_output_frame(AC3EncodeContext *s, unsigned char *frame)
1971 {
1972  PutBitContext pb;
1973  int blk;
1974 
1975  init_put_bits(&pb, frame, s->frame_size);
1976 
1977  s->output_frame_header(s, &pb);
1978 
1979  for (blk = 0; blk < s->num_blocks; blk++)
1980  output_audio_block(s, &pb, blk);
1981 
1982  output_frame_end(s, &pb);
1983 }
1984 
1986  const AVFrame *frame, int *got_packet_ptr)
1987 {
1988  AC3EncodeContext *const s = avctx->priv_data;
1989  int ret;
1990 
1991  if (s->options.allow_per_frame_metadata) {
1993  if (ret)
1994  return ret;
1995  }
1996 
1997  if (s->bit_alloc.sr_code == 1 || s->eac3)
1999 
2000  s->encode_frame(s, frame->extended_data);
2001 
2003 
2005 
2007  if (ret) {
2008  av_log(avctx, AV_LOG_ERROR, "Bit allocation failed. Try increasing the bitrate.\n");
2009  return ret;
2010  }
2011 
2013 
2015 
2016  ret = ff_get_encode_buffer(avctx, avpkt, s->frame_size, 0);
2017  if (ret < 0)
2018  return ret;
2019  ac3_output_frame(s, avpkt->data);
2020 
2021  if (frame->pts != AV_NOPTS_VALUE)
2022  avpkt->pts = frame->pts - ff_samples_to_time_base(avctx, avctx->initial_padding);
2023 
2024  *got_packet_ptr = 1;
2025  return 0;
2026 }
2027 
2029 {
2030 #ifdef DEBUG
2031  AVCodecContext *avctx = s->avctx;
2032  AC3EncOptions *opt = &s->options;
2033  const char *msg;
2034  char strbuf[32];
2035 
2036  switch (s->bitstream_id) {
2037  case 6: msg = "AC-3 (alt syntax)"; break;
2038  case 8: msg = "AC-3 (standard)"; break;
2039  case 16: msg = "E-AC-3 (enhanced)"; break;
2040  default: msg = "ERROR";
2041  }
2042  ff_dlog(avctx, "bitstream_id: %s (%d)\n", msg, s->bitstream_id);
2043  ff_dlog(avctx, "sample_fmt: %s\n", av_get_sample_fmt_name(avctx->sample_fmt));
2044  av_channel_layout_describe(&avctx->ch_layout, strbuf, sizeof(strbuf));
2045  ff_dlog(avctx, "channel_layout: %s\n", strbuf);
2046  ff_dlog(avctx, "sample_rate: %d\n", s->sample_rate);
2047  ff_dlog(avctx, "bit_rate: %d\n", s->bit_rate);
2048  ff_dlog(avctx, "blocks/frame: %d (code=%d)\n", s->num_blocks, s->num_blks_code);
2049  if (s->cutoff)
2050  ff_dlog(avctx, "cutoff: %d\n", s->cutoff);
2051 
2052  ff_dlog(avctx, "per_frame_metadata: %s\n",
2053  opt->allow_per_frame_metadata?"on":"off");
2054  if (s->has_center)
2055  ff_dlog(avctx, "center_mixlev: %0.3f (%d)\n", opt->center_mix_level,
2056  s->center_mix_level);
2057  else
2058  ff_dlog(avctx, "center_mixlev: {not written}\n");
2059  if (s->has_surround)
2060  ff_dlog(avctx, "surround_mixlev: %0.3f (%d)\n", opt->surround_mix_level,
2061  s->surround_mix_level);
2062  else
2063  ff_dlog(avctx, "surround_mixlev: {not written}\n");
2064  if (opt->audio_production_info) {
2065  ff_dlog(avctx, "mixing_level: %ddB\n", opt->mixing_level);
2066  switch (opt->room_type) {
2067  case AC3ENC_OPT_NOT_INDICATED: msg = "notindicated"; break;
2068  case AC3ENC_OPT_LARGE_ROOM: msg = "large"; break;
2069  case AC3ENC_OPT_SMALL_ROOM: msg = "small"; break;
2070  default:
2071  snprintf(strbuf, sizeof(strbuf), "ERROR (%d)", opt->room_type);
2072  msg = strbuf;
2073  }
2074  ff_dlog(avctx, "room_type: %s\n", msg);
2075  } else {
2076  ff_dlog(avctx, "mixing_level: {not written}\n");
2077  ff_dlog(avctx, "room_type: {not written}\n");
2078  }
2079  ff_dlog(avctx, "copyright: %s\n", opt->copyright?"on":"off");
2080  ff_dlog(avctx, "dialnorm: %ddB\n", opt->dialogue_level);
2081  if (s->channel_mode == AC3_CHMODE_STEREO) {
2082  switch (opt->dolby_surround_mode) {
2083  case AC3ENC_OPT_NOT_INDICATED: msg = "notindicated"; break;
2084  case AC3ENC_OPT_MODE_ON: msg = "on"; break;
2085  case AC3ENC_OPT_MODE_OFF: msg = "off"; break;
2086  default:
2087  snprintf(strbuf, sizeof(strbuf), "ERROR (%d)", opt->dolby_surround_mode);
2088  msg = strbuf;
2089  }
2090  ff_dlog(avctx, "dsur_mode: %s\n", msg);
2091  } else {
2092  ff_dlog(avctx, "dsur_mode: {not written}\n");
2093  }
2094  ff_dlog(avctx, "original: %s\n", opt->original?"on":"off");
2095 
2096  if (s->bitstream_id == 6) {
2097  if (opt->extended_bsi_1) {
2098  switch (opt->preferred_stereo_downmix) {
2099  case AC3ENC_OPT_NOT_INDICATED: msg = "notindicated"; break;
2100  case AC3ENC_OPT_DOWNMIX_LTRT: msg = "ltrt"; break;
2101  case AC3ENC_OPT_DOWNMIX_LORO: msg = "loro"; break;
2102  default:
2103  snprintf(strbuf, sizeof(strbuf), "ERROR (%d)", opt->preferred_stereo_downmix);
2104  msg = strbuf;
2105  }
2106  ff_dlog(avctx, "dmix_mode: %s\n", msg);
2107  ff_dlog(avctx, "ltrt_cmixlev: %0.3f (%d)\n",
2108  opt->ltrt_center_mix_level, s->ltrt_center_mix_level);
2109  ff_dlog(avctx, "ltrt_surmixlev: %0.3f (%d)\n",
2110  opt->ltrt_surround_mix_level, s->ltrt_surround_mix_level);
2111  ff_dlog(avctx, "loro_cmixlev: %0.3f (%d)\n",
2112  opt->loro_center_mix_level, s->loro_center_mix_level);
2113  ff_dlog(avctx, "loro_surmixlev: %0.3f (%d)\n",
2114  opt->loro_surround_mix_level, s->loro_surround_mix_level);
2115  } else {
2116  ff_dlog(avctx, "extended bitstream info 1: {not written}\n");
2117  }
2118  if (opt->extended_bsi_2) {
2119  switch (opt->dolby_surround_ex_mode) {
2120  case AC3ENC_OPT_NOT_INDICATED: msg = "notindicated"; break;
2121  case AC3ENC_OPT_MODE_ON: msg = "on"; break;
2122  case AC3ENC_OPT_MODE_OFF: msg = "off"; break;
2123  default:
2124  snprintf(strbuf, sizeof(strbuf), "ERROR (%d)", opt->dolby_surround_ex_mode);
2125  msg = strbuf;
2126  }
2127  ff_dlog(avctx, "dsurex_mode: %s\n", msg);
2128  switch (opt->dolby_headphone_mode) {
2129  case AC3ENC_OPT_NOT_INDICATED: msg = "notindicated"; break;
2130  case AC3ENC_OPT_MODE_ON: msg = "on"; break;
2131  case AC3ENC_OPT_MODE_OFF: msg = "off"; break;
2132  default:
2133  snprintf(strbuf, sizeof(strbuf), "ERROR (%d)", opt->dolby_headphone_mode);
2134  msg = strbuf;
2135  }
2136  ff_dlog(avctx, "dheadphone_mode: %s\n", msg);
2137 
2138  switch (opt->ad_converter_type) {
2139  case AC3ENC_OPT_ADCONV_STANDARD: msg = "standard"; break;
2140  case AC3ENC_OPT_ADCONV_HDCD: msg = "hdcd"; break;
2141  default:
2142  snprintf(strbuf, sizeof(strbuf), "ERROR (%d)", opt->ad_converter_type);
2143  msg = strbuf;
2144  }
2145  ff_dlog(avctx, "ad_conv_type: %s\n", msg);
2146  } else {
2147  ff_dlog(avctx, "extended bitstream info 2: {not written}\n");
2148  }
2149  }
2150 #endif
2151 }
2152 
2153 /**
2154  * Finalize encoding and free any memory allocated by the encoder.
2155  *
2156  * @param avctx Codec context
2157  */
2159 {
2160  AC3EncodeContext *s = avctx->priv_data;
2161 
2162  for (int ch = 0; ch < s->channels; ch++)
2163  av_freep(&s->planar_samples[ch]);
2164  av_freep(&s->bap_buffer);
2165  av_freep(&s->bap1_buffer);
2166  av_freep(&s->mdct_coef_buffer);
2167  av_freep(&s->fixed_coef_buffer);
2168  av_freep(&s->exp_buffer);
2169  av_freep(&s->grouped_exp_buffer);
2170  av_freep(&s->psd_buffer);
2171  av_freep(&s->band_psd_buffer);
2172  av_freep(&s->mask_buffer);
2173  av_freep(&s->qmant_buffer);
2174  av_freep(&s->cpl_coord_buffer);
2175  av_freep(&s->fdsp);
2176 
2177  av_tx_uninit(&s->tx);
2178 
2179  return 0;
2180 }
2181 
2182 
2183 /*
2184  * Set channel information during initialization.
2185  */
2187 {
2188  AC3EncodeContext *s = avctx->priv_data;
2189  uint64_t mask = av_channel_layout_subset(&avctx->ch_layout, ~(uint64_t)0);
2190  int channels = avctx->ch_layout.nb_channels;
2191 
2192  s->lfe_on = !!(mask & AV_CH_LOW_FREQUENCY);
2193  s->channels = channels;
2194  s->fbw_channels = channels - s->lfe_on;
2195  s->lfe_channel = s->lfe_on ? s->fbw_channels + 1 : -1;
2196 
2197  switch (mask & ~AV_CH_LOW_FREQUENCY) {
2198  case AV_CH_LAYOUT_MONO: s->channel_mode = AC3_CHMODE_MONO; break;
2199  case AV_CH_LAYOUT_STEREO: s->channel_mode = AC3_CHMODE_STEREO; break;
2200  case AV_CH_LAYOUT_SURROUND: s->channel_mode = AC3_CHMODE_3F; break;
2201  case AV_CH_LAYOUT_2_1: s->channel_mode = AC3_CHMODE_2F1R; break;
2202  case AV_CH_LAYOUT_4POINT0: s->channel_mode = AC3_CHMODE_3F1R; break;
2203  case AV_CH_LAYOUT_QUAD:
2204  case AV_CH_LAYOUT_2_2: s->channel_mode = AC3_CHMODE_2F2R; break;
2205  case AV_CH_LAYOUT_5POINT0:
2206  case AV_CH_LAYOUT_5POINT0_BACK: s->channel_mode = AC3_CHMODE_3F2R; break;
2207  }
2208  s->has_center = (s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO;
2209  s->has_surround = s->channel_mode & 0x04;
2210 
2211  s->channel_map = ac3_enc_channel_map[s->channel_mode][s->lfe_on];
2212 }
2213 
2214 
2216 {
2217  AVCodecContext *avctx = s->avctx;
2218  int ret;
2219 
2220  set_channel_info(avctx);
2221 
2222  for (int i = 0;; i++) {
2223  if (ff_ac3_sample_rate_tab[i] == avctx->sample_rate) {
2224  s->bit_alloc.sr_code = i;
2225  break;
2226  }
2228  }
2229  s->sample_rate = avctx->sample_rate;
2230  s->bitstream_id = s->eac3 ? 16 : 8;
2231 
2232  /* select a default bit rate if not set by the user */
2233  if (!avctx->bit_rate) {
2234  switch (s->fbw_channels) {
2235  case 1: avctx->bit_rate = 96000; break;
2236  case 2: avctx->bit_rate = 192000; break;
2237  case 3: avctx->bit_rate = 320000; break;
2238  case 4: avctx->bit_rate = 384000; break;
2239  case 5: avctx->bit_rate = 448000; break;
2240  }
2241  }
2242 
2243  /* validate bit rate */
2244  if (s->eac3) {
2245  int max_br, min_br, wpf, min_br_code;
2246  int num_blks_code, num_blocks, frame_samples;
2247  long long min_br_dist;
2248 
2249  /* calculate min/max bitrate */
2250  /* TODO: More testing with 3 and 2 blocks. All E-AC-3 samples I've
2251  found use either 6 blocks or 1 block, even though 2 or 3 blocks
2252  would work as far as the bit rate is concerned. */
2253  for (num_blks_code = 3; num_blks_code >= 0; num_blks_code--) {
2254  num_blocks = ((int[]){ 1, 2, 3, 6 })[num_blks_code];
2255  frame_samples = AC3_BLOCK_SIZE * num_blocks;
2256  max_br = 2048 * s->sample_rate / frame_samples * 16;
2257  min_br = ((s->sample_rate + (frame_samples-1)) / frame_samples) * 16;
2258  if (avctx->bit_rate <= max_br)
2259  break;
2260  }
2261  if (avctx->bit_rate < min_br || avctx->bit_rate > max_br) {
2262  av_log(avctx, AV_LOG_ERROR, "invalid bit rate. must be %d to %d "
2263  "for this sample rate\n", min_br, max_br);
2264  return AVERROR(EINVAL);
2265  }
2266  s->num_blks_code = num_blks_code;
2267  s->num_blocks = num_blocks;
2268 
2269  /* calculate words-per-frame for the selected bitrate */
2270  wpf = (avctx->bit_rate / 16) * frame_samples / s->sample_rate;
2271  av_assert1(wpf > 0 && wpf <= 2048);
2272 
2273  /* find the closest AC-3 bitrate code to the selected bitrate.
2274  this is needed for lookup tables for bandwidth and coupling
2275  parameter selection */
2276  min_br_code = -1;
2277  min_br_dist = INT64_MAX;
2278  for (int i = 0; i < 19; i++) {
2279  long long br_dist = llabs(ff_ac3_bitrate_tab[i] * 1000 - avctx->bit_rate);
2280  if (br_dist < min_br_dist) {
2281  min_br_dist = br_dist;
2282  min_br_code = i;
2283  }
2284  }
2285 
2286  /* make sure the minimum frame size is below the average frame size */
2287  s->frame_size_code = min_br_code << 1;
2288  while (wpf > 1 && wpf * s->sample_rate / AC3_FRAME_SIZE * 16 > avctx->bit_rate)
2289  wpf--;
2290  s->frame_size_min = 2 * wpf;
2291  } else {
2292  int best_br = 0, best_code = 0;
2293  long long best_diff = INT64_MAX;
2294  for (int i = 0; i < 19; i++) {
2295  int br = ff_ac3_bitrate_tab[i] * 1000;
2296  long long diff = llabs(br - avctx->bit_rate);
2297  if (diff < best_diff) {
2298  best_br = br;
2299  best_code = i;
2300  best_diff = diff;
2301  }
2302  if (!best_diff)
2303  break;
2304  }
2305  avctx->bit_rate = best_br;
2306  s->frame_size_code = best_code << 1;
2307  s->frame_size_min = 2 * ff_ac3_frame_size_tab[s->frame_size_code][s->bit_alloc.sr_code];
2308  s->num_blks_code = 0x3;
2309  s->num_blocks = 6;
2310  }
2311  s->bit_rate = avctx->bit_rate;
2312  s->frame_size = s->frame_size_min;
2313 
2314  /* validate cutoff */
2315  if (avctx->cutoff < 0) {
2316  av_log(avctx, AV_LOG_ERROR, "invalid cutoff frequency\n");
2317  return AVERROR(EINVAL);
2318  }
2319  s->cutoff = avctx->cutoff;
2320  if (s->cutoff > (s->sample_rate >> 1))
2321  s->cutoff = s->sample_rate >> 1;
2322 
2324  if (ret)
2325  return ret;
2326 
2327  s->rematrixing_enabled = s->options.stereo_rematrixing &&
2328  (s->channel_mode == AC3_CHMODE_STEREO);
2329 
2330  s->cpl_enabled = s->options.channel_coupling &&
2331  s->channel_mode >= AC3_CHMODE_STEREO;
2332 
2333  return 0;
2334 }
2335 
2336 
2337 /*
2338  * Set bandwidth for all channels.
2339  * The user can optionally supply a cutoff frequency. Otherwise an appropriate
2340  * default value will be used.
2341  */
2343 {
2344  int blk, ch, av_uninit(cpl_start);
2345 
2346  if (s->cutoff) {
2347  /* calculate bandwidth based on user-specified cutoff frequency */
2348  int fbw_coeffs;
2349  fbw_coeffs = s->cutoff * 2 * AC3_MAX_COEFS / s->sample_rate;
2350  s->bandwidth_code = av_clip((fbw_coeffs - 73) / 3, 0, 60);
2351  } else {
2352  /* use default bandwidth setting */
2353  s->bandwidth_code = ac3_bandwidth_tab[s->fbw_channels-1][s->bit_alloc.sr_code][s->frame_size_code/2];
2354  }
2355 
2356  /* set number of coefficients for each channel */
2357  for (ch = 1; ch <= s->fbw_channels; ch++) {
2358  s->start_freq[ch] = 0;
2359  for (blk = 0; blk < s->num_blocks; blk++)
2360  s->blocks[blk].end_freq[ch] = s->bandwidth_code * 3 + 73;
2361  }
2362  /* LFE channel always has 7 coefs */
2363  if (s->lfe_on) {
2364  s->start_freq[s->lfe_channel] = 0;
2365  for (blk = 0; blk < s->num_blocks; blk++)
2366  s->blocks[blk].end_freq[ch] = 7;
2367  }
2368 
2369  /* initialize coupling strategy */
2370  if (s->cpl_enabled) {
2371  if (s->options.cpl_start != AC3ENC_OPT_AUTO) {
2372  cpl_start = s->options.cpl_start;
2373  } else {
2374  cpl_start = ac3_coupling_start_tab[s->channel_mode-2][s->bit_alloc.sr_code][s->frame_size_code/2];
2375  if (cpl_start < 0) {
2376  if (s->options.channel_coupling == AC3ENC_OPT_AUTO)
2377  s->cpl_enabled = 0;
2378  else
2379  cpl_start = 15;
2380  }
2381  }
2382  }
2383  if (s->cpl_enabled) {
2384  int i, cpl_start_band, cpl_end_band;
2385  uint8_t *cpl_band_sizes = s->cpl_band_sizes;
2386 
2387  cpl_end_band = s->bandwidth_code / 4 + 3;
2388  cpl_start_band = av_clip(cpl_start, 0, FFMIN(cpl_end_band-1, 15));
2389 
2390  s->num_cpl_subbands = cpl_end_band - cpl_start_band;
2391 
2392  s->num_cpl_bands = 1;
2393  *cpl_band_sizes = 12;
2394  for (i = cpl_start_band + 1; i < cpl_end_band; i++) {
2396  *cpl_band_sizes += 12;
2397  } else {
2398  s->num_cpl_bands++;
2399  cpl_band_sizes++;
2400  *cpl_band_sizes = 12;
2401  }
2402  }
2403 
2404  s->start_freq[CPL_CH] = cpl_start_band * 12 + 37;
2405  s->cpl_end_freq = cpl_end_band * 12 + 37;
2406  for (blk = 0; blk < s->num_blocks; blk++)
2407  s->blocks[blk].end_freq[CPL_CH] = s->cpl_end_freq;
2408  }
2409 }
2410 
2411 
2413 {
2414  int blk, ch;
2415  int channels = s->channels + 1; /* includes coupling channel */
2416  int channel_blocks = channels * s->num_blocks;
2417  int total_coefs = AC3_MAX_COEFS * channel_blocks;
2418  uint8_t *cpl_coord_mant_buffer;
2419  const unsigned sampletype_size = SAMPLETYPE_SIZE(s);
2420 
2421  for (int ch = 0; ch < s->channels; ch++) {
2422  s->planar_samples[ch] = av_mallocz(AC3_BLOCK_SIZE * sampletype_size);
2423  if (!s->planar_samples[ch])
2424  return AVERROR(ENOMEM);
2425  }
2426 
2427  if (!FF_ALLOC_TYPED_ARRAY(s->bap_buffer, total_coefs) ||
2428  !FF_ALLOC_TYPED_ARRAY(s->bap1_buffer, total_coefs) ||
2429  !FF_ALLOCZ_TYPED_ARRAY(s->mdct_coef_buffer, total_coefs) ||
2430  !FF_ALLOC_TYPED_ARRAY(s->exp_buffer, total_coefs) ||
2431  !FF_ALLOC_TYPED_ARRAY(s->grouped_exp_buffer, channel_blocks * 128) ||
2432  !FF_ALLOC_TYPED_ARRAY(s->psd_buffer, total_coefs) ||
2433  !FF_ALLOC_TYPED_ARRAY(s->band_psd_buffer, channel_blocks * 64) ||
2434  !FF_ALLOC_TYPED_ARRAY(s->mask_buffer, channel_blocks * 64) ||
2435  !FF_ALLOC_TYPED_ARRAY(s->qmant_buffer, total_coefs))
2436  return AVERROR(ENOMEM);
2437 
2438  if (!s->fixed_point) {
2439  if (!FF_ALLOCZ_TYPED_ARRAY(s->fixed_coef_buffer, total_coefs))
2440  return AVERROR(ENOMEM);
2441  }
2442  if (s->cpl_enabled) {
2443  if (!FF_ALLOC_TYPED_ARRAY(s->cpl_coord_buffer, channel_blocks * 32))
2444  return AVERROR(ENOMEM);
2445  cpl_coord_mant_buffer = s->cpl_coord_buffer + 16 * channel_blocks;
2446  }
2447  for (blk = 0; blk < s->num_blocks; blk++) {
2448  AC3Block *block = &s->blocks[blk];
2449 
2450  for (ch = 0; ch < channels; ch++) {
2451  /* arrangement: block, channel, coeff */
2452  block->grouped_exp[ch] = &s->grouped_exp_buffer[128 * (blk * channels + ch)];
2453  block->psd[ch] = &s->psd_buffer [AC3_MAX_COEFS * (blk * channels + ch)];
2454  block->band_psd[ch] = &s->band_psd_buffer [64 * (blk * channels + ch)];
2455  block->mask[ch] = &s->mask_buffer [64 * (blk * channels + ch)];
2456  block->qmant[ch] = &s->qmant_buffer [AC3_MAX_COEFS * (blk * channels + ch)];
2457  if (s->cpl_enabled) {
2458  block->cpl_coord_exp[ch] = &s->cpl_coord_buffer [16 * (blk * channels + ch)];
2459  block->cpl_coord_mant[ch] = &cpl_coord_mant_buffer[16 * (blk * channels + ch)];
2460  }
2461 
2462  /* arrangement: channel, block, coeff */
2463  block->exp[ch] = &s->exp_buffer [AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2464  block->mdct_coef[ch] = &s->mdct_coef_buffer [AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2465  if (s->fixed_point)
2466  block->fixed_coef[ch] = (int32_t *)block->mdct_coef[ch];
2467  else
2468  block->fixed_coef[ch] = &s->fixed_coef_buffer[AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2469  }
2470  }
2471 
2472  return 0;
2473 }
2474 
2475 
2477 {
2478  static AVOnce init_static_once = AV_ONCE_INIT;
2479  AC3EncodeContext *s = avctx->priv_data;
2480  int ret, frame_size_58;
2481 
2482  s->avctx = avctx;
2483 
2484  ret = validate_options(s);
2485  if (ret)
2486  return ret;
2487 
2488  avctx->frame_size = AC3_BLOCK_SIZE * s->num_blocks;
2490 
2491  s->bitstream_mode = avctx->audio_service_type;
2492  if (s->bitstream_mode == AV_AUDIO_SERVICE_TYPE_KARAOKE)
2493  s->bitstream_mode = 0x7;
2494 
2495  s->bits_written = 0;
2496  s->samples_written = 0;
2497 
2498  /* calculate crc_inv for both possible frame sizes */
2499  frame_size_58 = (( s->frame_size >> 2) + ( s->frame_size >> 4)) << 1;
2500  s->crc_inv[0] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);
2501  if (s->bit_alloc.sr_code == 1) {
2502  frame_size_58 = (((s->frame_size+2) >> 2) + ((s->frame_size+2) >> 4)) << 1;
2503  s->crc_inv[1] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);
2504  }
2505 
2506  if (!s->output_frame_header)
2507  s->output_frame_header = ac3_output_frame_header;
2508 
2509  set_bandwidth(s);
2510 
2511  bit_alloc_init(s);
2512 
2513  ret = allocate_buffers(s);
2514  if (ret)
2515  return ret;
2516 
2517  ff_audiodsp_init(&s->adsp);
2518  ff_me_cmp_init(&s->mecc, avctx);
2519  ff_ac3dsp_init(&s->ac3dsp);
2520 
2521  dprint_options(s);
2522 
2523  ff_thread_once(&init_static_once, exponent_init);
2524 
2525  return 0;
2526 }
FF_ALLOCZ_TYPED_ARRAY
#define FF_ALLOCZ_TYPED_ARRAY(p, nelem)
Definition: internal.h:78
frame_samples
static int frame_samples(const SyncQueue *sq, SyncQueueFrame frame)
Definition: sync_queue.c:141
OFFSET
#define OFFSET(param)
Definition: ac3enc.c:82
AVCodecContext::frame_size
int frame_size
Number of samples per channel in an audio frame.
Definition: avcodec.h:1077
AC3_CHMODE_3F
@ AC3_CHMODE_3F
Definition: ac3defs.h:58
nb_coefs
static int nb_coefs(int length, int level, uint64_t sn)
Definition: af_afwtdn.c:515
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
ff_ac3_fast_decay_tab
const uint8_t ff_ac3_fast_decay_tab[4]
Definition: ac3tab.c:130
EXP_D45
#define EXP_D45
Definition: ac3defs.h:43
AV_CH_LAYOUT_5POINT0_BACK
#define AV_CH_LAYOUT_5POINT0_BACK
Definition: channel_layout.h:216
av_clip
#define av_clip
Definition: common.h:99
ac3_compute_bit_allocation
static int ac3_compute_bit_allocation(AC3EncodeContext *s)
Definition: ac3enc.c:1453
AC3EncOptions::mixing_level
int mixing_level
Definition: ac3enc.h:101
ac3_validate_metadata
static int ac3_validate_metadata(AC3EncodeContext *s)
Validate metadata options as set by AVOption system.
Definition: ac3enc.c:321
r
const char * r
Definition: vf_curves.c:127
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
opt.h
cmixlev_options
static const float cmixlev_options[CMIXLEV_NUM_OPTIONS]
Definition: ac3enc.c:64
AVCodecContext::audio_service_type
enum AVAudioServiceType audio_service_type
Type of service that the audio stream conveys.
Definition: avcodec.h:1097
AC3EncOptions::dolby_headphone_mode
int dolby_headphone_mode
Definition: ac3enc.h:113
mem_internal.h
AV_CHANNEL_LAYOUT_STEREO
#define AV_CHANNEL_LAYOUT_STEREO
Definition: channel_layout.h:379
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:1050
LEVEL_MINUS_6DB
#define LEVEL_MINUS_6DB
Definition: ac3.h:90
AVCRC
uint32_t AVCRC
Definition: crc.h:46
thread.h
ff_ac3_compute_coupling_strategy
void ff_ac3_compute_coupling_strategy(AC3EncodeContext *s)
Set the initial coupling strategy parameters prior to coupling analysis.
Definition: ac3enc.c:511
AV_CH_LAYOUT_MONO
#define AV_CH_LAYOUT_MONO
Definition: channel_layout.h:204
exp_strategy_reuse_tab
static const uint8_t exp_strategy_reuse_tab[4][6]
Table used to select exponent strategy based on exponent reuse block interval.
Definition: ac3enc.c:654
put_sbits
static void put_sbits(PutBitContext *pb, int n, int32_t value)
Definition: put_bits.h:281
init_put_bits
static void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
Initialize the PutBitContext s.
Definition: put_bits.h:62
AV_CHANNEL_LAYOUT_2_2
#define AV_CHANNEL_LAYOUT_2_2
Definition: channel_layout.h:386
COMMON_CHANNEL_MAP
#define COMMON_CHANNEL_MAP
Definition: ac3tab.h:48
AC3EncOptions::ltrt_surround_mix_level
float ltrt_surround_mix_level
Definition: ac3enc.h:108
AC3EncOptions::dialogue_level
int dialogue_level
Definition: ac3enc.h:95
surmixlev_options
static const float surmixlev_options[SURMIXLEV_NUM_OPTIONS]
Definition: ac3enc.c:69
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:374
put_bits
static void put_bits(Jpeg2000EncoderContext *s, int val, int n)
put n times val bit
Definition: j2kenc.c:223
AC3EncOptions::dolby_surround_mode
int dolby_surround_mode
Definition: ac3enc.h:99
AC3Mant::mant1_cnt
int mant1_cnt
Definition: ac3enc.c:60
count_mantissa_bits_init
static void count_mantissa_bits_init(uint16_t mant_cnt[AC3_MAX_BLOCKS][16])
Initialize mantissa counts.
Definition: ac3enc.c:1303
AVPacket::data
uint8_t * data
Definition: packet.h:524
AVOption
AVOption.
Definition: opt.h:357
encode.h
b
#define b
Definition: input.c:41
AV_AUDIO_SERVICE_TYPE_VOICE_OVER
@ AV_AUDIO_SERVICE_TYPE_VOICE_OVER
Definition: defs.h:230
LEVEL_MINUS_4POINT5DB
#define LEVEL_MINUS_4POINT5DB
Definition: ac3.h:89
ff_ac3_encode_frame
int ff_ac3_encode_frame(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr)
Definition: ac3enc.c:1985
ff_audiodsp_init
av_cold void ff_audiodsp_init(AudioDSPContext *c)
Definition: audiodsp.c:106
AC3EncOptions::center_mix_level
float center_mix_level
Definition: ac3enc.h:97
ff_eac3_get_frame_exp_strategy
void ff_eac3_get_frame_exp_strategy(AC3EncodeContext *s)
Determine frame exponent strategy use and indices.
Definition: eac3enc.c:71
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:313
validate_mix_level
static void validate_mix_level(void *log_ctx, const char *opt_name, float *opt_param, const float *list, int list_size, int default_value, int min_value, int *ctx_param)
Definition: ac3enc.c:297
exponent_group_tab
static uint8_t exponent_group_tab[2][3][256]
LUT for number of exponent groups.
Definition: ac3enc.c:150
AC3Mant::mant2_cnt
int mant2_cnt
Definition: ac3enc.c:60
ac3_process_exponents
static void ac3_process_exponents(AC3EncodeContext *s)
Calculate final exponents from the supplied MDCT coefficients and exponent shift.
Definition: ac3enc.c:944
ff_ac3dsp_init
av_cold void ff_ac3dsp_init(AC3DSPContext *c)
Definition: ac3dsp.c:377
count_mantissa_bits
static int count_mantissa_bits(AC3EncodeContext *s)
Definition: ac3enc.c:1345
ff_ac3_enc_options
const AVOption ff_ac3_enc_options[]
Definition: ac3enc.c:84
crc.h
FFCodecDefault
Definition: codec_internal.h:96
AVCodecContext::ch_layout
AVChannelLayout ch_layout
Audio channel layout.
Definition: avcodec.h:1065
AC3Mant::qmant4_ptr
int16_t * qmant4_ptr
mantissa pointers for bap=1,2,4
Definition: ac3enc.c:59
AVCodecContext::initial_padding
int initial_padding
Audio only.
Definition: avcodec.h:1122
AC3_CHMODE_3F1R
@ AC3_CHMODE_3F1R
Definition: ac3defs.h:60
ff_me_cmp_init
av_cold void ff_me_cmp_init(MECmpContext *c, AVCodecContext *avctx)
Definition: me_cmp.c:1008
FF_ALLOC_TYPED_ARRAY
#define FF_ALLOC_TYPED_ARRAY(p, nelem)
Definition: internal.h:77
ff_ac3_bap_tab
const uint8_t ff_ac3_bap_tab[64]
Definition: ac3tab.c:116
LEVEL_PLUS_3DB
#define LEVEL_PLUS_3DB
Definition: ac3.h:85
EXP_REUSE
#define EXP_REUSE
Definition: ac3defs.h:38
AV_CH_LAYOUT_STEREO
#define AV_CH_LAYOUT_STEREO
Definition: channel_layout.h:205
AV_CHANNEL_LAYOUT_SURROUND
#define AV_CHANNEL_LAYOUT_SURROUND
Definition: channel_layout.h:382
ac3_quantize_mantissas
static void ac3_quantize_mantissas(AC3EncodeContext *s)
Quantize mantissas using coefficients, exponents, and bit allocation pointers.
Definition: ac3enc.c:1608
bit_alloc
static int bit_alloc(AC3EncodeContext *s, int snr_offset)
Run the bit allocation with a given SNR offset.
Definition: ac3enc.c:1371
AV_CH_LAYOUT_QUAD
#define AV_CH_LAYOUT_QUAD
Definition: channel_layout.h:213
set_bandwidth
static av_cold void set_bandwidth(AC3EncodeContext *s)
Definition: ac3enc.c:2342
ff_ac3_ch_layouts
const AVChannelLayout ff_ac3_ch_layouts[19]
List of supported channel layouts.
Definition: ac3enc.c:156
avassert.h
ff_thread_once
static int ff_thread_once(char *control, void(*routine)(void))
Definition: thread.h:205
AC3EncOptions::eac3_mixing_metadata
int eac3_mixing_metadata
Definition: ac3enc.h:115
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
av_cold
#define av_cold
Definition: attributes.h:90
AV_CH_LOW_FREQUENCY
#define AV_CH_LOW_FREQUENCY
Definition: channel_layout.h:171
mask
static const uint16_t mask[17]
Definition: lzw.c:38
av_channel_layout_describe
int av_channel_layout_describe(const AVChannelLayout *channel_layout, char *buf, size_t buf_size)
Get a human-readable string describing the channel layout properties.
Definition: channel_layout.c:644
AV_CHANNEL_LAYOUT_4POINT0
#define AV_CHANNEL_LAYOUT_4POINT0
Definition: channel_layout.h:384
emms_c
#define emms_c()
Definition: emms.h:63
EXP_NEW
#define EXP_NEW
Definition: ac3defs.h:39
ac3_apply_rematrixing
static void ac3_apply_rematrixing(AC3EncodeContext *s)
Apply stereo rematrixing to coefficients based on rematrixing flags.
Definition: ac3enc.c:582
s
#define s(width, name)
Definition: cbs_vp9.c:198
EXTMIXLEV_NUM_OPTIONS
#define EXTMIXLEV_NUM_OPTIONS
Definition: ac3enc.c:73
LEVEL_MINUS_3DB
#define LEVEL_MINUS_3DB
Definition: ac3.h:88
set_channel_info
static av_cold void set_channel_info(AVCodecContext *avctx)
Definition: ac3enc.c:2186
validate_float_option
static int validate_float_option(float v, const float *v_list, int v_list_size)
Definition: ac3enc.c:281
AC3_MAX_COEFS
#define AC3_MAX_COEFS
Definition: ac3defs.h:29
quantize_mantissas_blk_ch
static void quantize_mantissas_blk_ch(AC3Mant *s, int32_t *fixed_coef, uint8_t *exp, uint8_t *bap, int16_t *qmant, int start_freq, int end_freq)
Quantize a set of mantissas for a single channel in a single block.
Definition: ac3enc.c:1513
AV_CHANNEL_LAYOUT_5POINT0_BACK
#define AV_CHANNEL_LAYOUT_5POINT0_BACK
Definition: channel_layout.h:390
ff_ac3_floor_tab
const int16_t ff_ac3_floor_tab[8]
Definition: ac3tab.c:142
LOCAL_ALIGNED_16
#define LOCAL_ALIGNED_16(t, v,...)
Definition: mem_internal.h:150
encode_exponents_blk_ch
static void encode_exponents_blk_ch(uint8_t *exp, int nb_exps, int exp_strategy, int cpl)
Update the exponents so that they are the ones the decoder will decode.
Definition: ac3enc.c:731
ac3_group_exponents
static void ac3_group_exponents(AC3EncodeContext *s)
Group exponents.
Definition: ac3enc.c:886
extmixlev_options
static const float extmixlev_options[EXTMIXLEV_NUM_OPTIONS]
Definition: ac3enc.c:74
channels
channels
Definition: aptx.h:31
AC3EncOptions::audio_production_info
int audio_production_info
Definition: ac3enc.h:100
blk
#define blk(i)
Definition: sha.c:186
av_get_sample_fmt_name
const char * av_get_sample_fmt_name(enum AVSampleFormat sample_fmt)
Return the name of sample_fmt, or NULL if sample_fmt is not recognized.
Definition: samplefmt.c:51
PutBitContext
Definition: put_bits.h:50
AV_CH_LAYOUT_2_1
#define AV_CH_LAYOUT_2_1
Definition: channel_layout.h:207
if
if(ret)
Definition: filter_design.txt:179
AV_CRC_16_ANSI
@ AV_CRC_16_ANSI
Definition: crc.h:50
SURMIXLEV_NUM_OPTIONS
#define SURMIXLEV_NUM_OPTIONS
Definition: ac3enc.c:68
ac3defs.h
EXP_D15
#define EXP_D15
Definition: ac3defs.h:41
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
AV_ONCE_INIT
#define AV_ONCE_INIT
Definition: thread.h:203
AC3EncOptions::ad_converter_type
int ad_converter_type
Definition: ac3enc.h:114
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
PutBitContext::buf
uint8_t * buf
Definition: put_bits.h:53
AC3ENC_OPT_AUTO
#define AC3ENC_OPT_AUTO
Definition: ac3enc.h:72
NULL
#define NULL
Definition: coverity.c:32
AC3_FRAME_SIZE
#define AC3_FRAME_SIZE
Definition: ac3defs.h:32
bits_left
#define bits_left
Definition: bitstream.h:114
ac3enc.h
extract_exponents
static void extract_exponents(AC3EncodeContext *s)
Definition: ac3enc.c:635
AV_WB16
#define AV_WB16(p, v)
Definition: intreadwrite.h:403
AC3ENC_OPT_DOWNMIX_DPLII
#define AC3ENC_OPT_DOWNMIX_DPLII
Definition: ac3enc.h:85
ff_samples_to_time_base
static av_always_inline int64_t ff_samples_to_time_base(const AVCodecContext *avctx, int64_t samples)
Rescale from sample rate to AVCodecContext.time_base.
Definition: encode.h:90
AVCodecContext::bit_rate
int64_t bit_rate
the average bitrate
Definition: avcodec.h:495
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:237
DBA_NONE
@ DBA_NONE
Definition: ac3defs.h:49
AC3ENC_OPT_NONE
#define AC3ENC_OPT_NONE
Definition: ac3enc.h:71
list
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining list
Definition: filter_design.txt:25
ac3dsp.h
count_frame_bits
static void count_frame_bits(AC3EncodeContext *s)
Definition: ac3enc.c:1105
AV_AUDIO_SERVICE_TYPE_EMERGENCY
@ AV_AUDIO_SERVICE_TYPE_EMERGENCY
Definition: defs.h:229
AC3EncodeContext
AC-3 encoder private context.
Definition: ac3enc.h:158
exp
int8_t exp
Definition: eval.c:73
AC3EncOptions::extended_bsi_1
int extended_bsi_1
Definition: ac3enc.h:105
AC3EncOptions::copyright
int copyright
Definition: ac3enc.h:103
AC3ENC_OPT_DOWNMIX_LORO
#define AC3ENC_OPT_DOWNMIX_LORO
Definition: ac3enc.h:84
AVOnce
#define AVOnce
Definition: thread.h:202
AC3Block
Data for a single audio block.
Definition: ac3enc.h:128
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
ff_dlog
#define ff_dlog(a,...)
Definition: tableprint_vlc.h:28
ac3_bandwidth_tab
static const uint8_t ac3_bandwidth_tab[5][3][19]
LUT to select the bandwidth code based on the bit rate, sample rate, and number of full-bandwidth cha...
Definition: ac3enc.c:211
pow_poly
static unsigned int pow_poly(unsigned int a, unsigned int n, unsigned int poly)
Definition: ac3enc.c:1903
AC3_CHMODE_STEREO
@ AC3_CHMODE_STEREO
Definition: ac3defs.h:57
AC3EncOptions::eac3_info_metadata
int eac3_info_metadata
Definition: ac3enc.h:116
AC3EncOptions::dolby_surround_ex_mode
int dolby_surround_ex_mode
Definition: ac3enc.h:112
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:303
codec_internal.h
AC3_BLOCK_SIZE
#define AC3_BLOCK_SIZE
Definition: ac3defs.h:30
ff_ac3_db_per_bit_tab
const uint16_t ff_ac3_db_per_bit_tab[4]
Definition: ac3tab.c:138
AC3ENC_OPT_ADCONV_HDCD
#define AC3ENC_OPT_ADCONV_HDCD
Definition: ac3enc.h:87
AVCodecContext::sample_fmt
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1057
bit_alloc_masking
static void bit_alloc_masking(AC3EncodeContext *s)
Definition: ac3enc.c:1248
LEVEL_MINUS_1POINT5DB
#define LEVEL_MINUS_1POINT5DB
Definition: ac3.h:87
AV_NOPTS_VALUE
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
AC3ENC_OPT_ON
#define AC3ENC_OPT_ON
Definition: ac3enc.h:74
AC3EncOptions::room_type
int room_type
Definition: ac3enc.h:102
EXP_DIFF_THRESHOLD
#define EXP_DIFF_THRESHOLD
Exponent Difference Threshold.
Definition: ac3enc.c:649
AC3EncOptions
Encoding Options used by AVOption.
Definition: ac3enc.h:93
diff
static av_always_inline int diff(const struct color_info *a, const struct color_info *b, const int trans_thresh)
Definition: vf_paletteuse.c:165
AC3ENC_OPT_SMALL_ROOM
#define AC3ENC_OPT_SMALL_ROOM
Definition: ac3enc.h:82
ac3_output_frame
static void ac3_output_frame(AC3EncodeContext *s, unsigned char *frame)
Write the frame to the output bitstream.
Definition: ac3enc.c:1970
AC3ENC_OPT_ADCONV_STANDARD
#define AC3ENC_OPT_ADCONV_STANDARD
Definition: ac3enc.h:86
a
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:41
av_crc_get_table
const AVCRC * av_crc_get_table(AVCRCId crc_id)
Get an initialized standard CRC table.
Definition: crc.c:374
LEVEL_ONE
#define LEVEL_ONE
Definition: ac3.h:93
CMIXLEV_NUM_OPTIONS
#define CMIXLEV_NUM_OPTIONS
Definition: ac3enc.c:63
sym_quant
static int sym_quant(int c, int e, int levels)
Symmetric quantization on 'levels' levels.
Definition: ac3enc.c:1473
attributes.h
AV_CHANNEL_ORDER_NATIVE
@ AV_CHANNEL_ORDER_NATIVE
The native channel order, i.e.
Definition: channel_layout.h:118
ac3_coupling_start_tab
static const int8_t ac3_coupling_start_tab[6][3][19]
LUT to select the coupling start band based on the bit rate, sample rate, and number of full-bandwidt...
Definition: ac3enc.c:244
bit_alloc_init
static av_cold void bit_alloc_init(AC3EncodeContext *s)
Definition: ac3enc.c:1069
eac3enc.h
av_tx_uninit
av_cold void av_tx_uninit(AVTXContext **ctx)
Frees a context and sets *ctx to NULL, does nothing when *ctx == NULL.
Definition: tx.c:295
CRC16_POLY
#define CRC16_POLY
CRC-16 Polynomial.
Definition: ac3enc.c:1883
AV_OPT_TYPE_FLOAT
@ AV_OPT_TYPE_FLOAT
Definition: opt.h:248
LEVEL_PLUS_1POINT5DB
#define LEVEL_PLUS_1POINT5DB
Definition: ac3.h:86
ff_ac3_rematrix_band_tab
const uint8_t ff_ac3_rematrix_band_tab[5]
Table of bin locations for rematrixing bands reference: Section 7.5.2 Rematrixing : Frequency Band De...
Definition: ac3tab.c:107
emms.h
AV_CH_LAYOUT_5POINT0
#define AV_CH_LAYOUT_5POINT0
Definition: channel_layout.h:214
CPL_CH
#define CPL_CH
coupling channel index
Definition: ac3defs.h:27
AC3Mant::qmant2_ptr
int16_t * qmant2_ptr
Definition: ac3enc.c:59
av_assert2
#define av_assert2(cond)
assert() equivalent, that does lie in speed critical code.
Definition: avassert.h:67
ff_ac3_sample_rate_tab
const int ff_ac3_sample_rate_tab[]
Definition: ac3tab.c:95
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:517
put_bits_count
static int put_bits_count(PutBitContext *s)
Definition: put_bits.h:80
AV_CHANNEL_LAYOUT_QUAD
#define AV_CHANNEL_LAYOUT_QUAD
Definition: channel_layout.h:387
internal.h
dprint_options
static void dprint_options(AC3EncodeContext *s)
Definition: ac3enc.c:2028
AC3ENC_OPT_OFF
#define AC3ENC_OPT_OFF
Definition: ac3enc.h:73
AVCodecContext::cutoff
int cutoff
Audio cutoff bandwidth (0 means "automatic")
Definition: avcodec.h:1090
count_frame_bits_fixed
static void count_frame_bits_fixed(AC3EncodeContext *s)
Definition: ac3enc.c:960
av_assert1
#define av_assert1(cond)
assert() equivalent, that does not lie in speed critical code.
Definition: avassert.h:56
mul_poly
static unsigned int mul_poly(unsigned int a, unsigned int b, unsigned int poly)
Definition: ac3enc.c:1886
ff_ac3_slow_decay_tab
const uint8_t ff_ac3_slow_decay_tab[4]
Definition: ac3tab.c:126
output_frame_end
static void output_frame_end(AC3EncodeContext *s, PutBitContext *pb)
Definition: ac3enc.c:1920
AC3EncOptions::original
int original
Definition: ac3enc.h:104
AC3Mant::mant4_cnt
int mant4_cnt
mantissa counts for bap=1,2,4
Definition: ac3enc.c:60
compute_exp_strategy
static void compute_exp_strategy(AC3EncodeContext *s)
Definition: ac3enc.c:665
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
AC3_MAX_BLOCKS
#define AC3_MAX_BLOCKS
Definition: ac3defs.h:31
av_mallocz
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:256
AC3Mant
Definition: ac3enc.c:58
AC3ENC_PARAM
#define AC3ENC_PARAM
Definition: ac3enc.c:83
ff_ac3_frame_size_tab
const uint16_t ff_ac3_frame_size_tab[38][3]
Possible frame sizes.
Definition: ac3tab.c:35
AC3ENC_OPT_MODE_OFF
#define AC3ENC_OPT_MODE_OFF
Definition: ac3enc.h:77
AC3_CHMODE_MONO
@ AC3_CHMODE_MONO
Definition: ac3defs.h:56
avcodec.h
AC3_CHMODE_3F2R
@ AC3_CHMODE_3F2R
Definition: ac3defs.h:62
AC3_CHMODE_2F1R
@ AC3_CHMODE_2F1R
Definition: ac3defs.h:59
av_uninit
#define av_uninit(x)
Definition: attributes.h:154
ret
ret
Definition: filter_design.txt:187
LEVEL_ZERO
#define LEVEL_ZERO
Definition: ac3.h:92
FFSWAP
#define FFSWAP(type, a, b)
Definition: macros.h:52
AVClass::class_name
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:71
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
AV_CH_LAYOUT_SURROUND
#define AV_CH_LAYOUT_SURROUND
Definition: channel_layout.h:208
AC3EncOptions::loro_surround_mix_level
float loro_surround_mix_level
Definition: ac3enc.h:110
AC3ENC_OPT_LARGE_ROOM
#define AC3ENC_OPT_LARGE_ROOM
Definition: ac3enc.h:81
AC3_CHMODE_2F2R
@ AC3_CHMODE_2F2R
Definition: ac3defs.h:61
output_audio_block
static void output_audio_block(AC3EncodeContext *s, PutBitContext *pb, int blk)
Definition: ac3enc.c:1693
AV_AUDIO_SERVICE_TYPE_KARAOKE
@ AV_AUDIO_SERVICE_TYPE_KARAOKE
Definition: defs.h:231
AC3EncOptions::ltrt_center_mix_level
float ltrt_center_mix_level
Definition: ac3enc.h:107
me_cmp.h
SAMPLETYPE_SIZE
#define SAMPLETYPE_SIZE(ctx)
Definition: ac3enc.c:55
AC3EncOptions::preferred_stereo_downmix
int preferred_stereo_downmix
Definition: ac3enc.h:106
AV_CHANNEL_LAYOUT_2_1
#define AV_CHANNEL_LAYOUT_2_1
Definition: channel_layout.h:381
ac3_adjust_frame_size
static void ac3_adjust_frame_size(AC3EncodeContext *s)
Adjust the frame size to make the average bit rate match the target bit rate.
Definition: ac3enc.c:494
AVCodecContext
main external API structure.
Definition: avcodec.h:445
AC3EncOptions::allow_per_frame_metadata
int allow_per_frame_metadata
Definition: ac3enc.h:119
put_bits_ptr
static uint8_t * put_bits_ptr(PutBitContext *s)
Return the pointer to the byte where the bitstream writer will put the next bit.
Definition: put_bits.h:377
channel_layout.h
asym_quant
static int asym_quant(int c, int e, int qbits)
Asymmetric quantization on 2^qbits levels.
Definition: ac3enc.c:1489
av_channel_layout_subset
uint64_t av_channel_layout_subset(const AVChannelLayout *channel_layout, uint64_t mask)
Find out what channels from a given set are present in a channel layout, without regard for their pos...
Definition: channel_layout.c:856
ff_get_encode_buffer
int ff_get_encode_buffer(AVCodecContext *avctx, AVPacket *avpkt, int64_t size, int flags)
Get a buffer for a packet.
Definition: encode.c:106
av_crc
uint32_t av_crc(const AVCRC *ctx, uint32_t crc, const uint8_t *buffer, size_t length)
Calculate the CRC of a block.
Definition: crc.c:392
FLT_OPTION_THRESHOLD
#define FLT_OPTION_THRESHOLD
Definition: ac3enc.c:279
ff_ac3_bitrate_tab
const uint16_t ff_ac3_bitrate_tab[19]
Definition: ac3tab.c:98
AV_AUDIO_SERVICE_TYPE_COMMENTARY
@ AV_AUDIO_SERVICE_TYPE_COMMENTARY
Definition: defs.h:228
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:245
allocate_buffers
static av_cold int allocate_buffers(AC3EncodeContext *s)
Definition: ac3enc.c:2412
ac3_output_frame_header
static void ac3_output_frame_header(AC3EncodeContext *s, PutBitContext *pb)
Definition: ac3enc.c:1637
ff_ac3enc_class
const AVClass ff_ac3enc_class
Definition: ac3enc.c:134
ff_ac3_enc_defaults
const FFCodecDefault ff_ac3_enc_defaults[]
Definition: ac3enc.c:141
ff_ac3_encode_init
av_cold int ff_ac3_encode_init(AVCodecContext *avctx)
Definition: ac3enc.c:2476
ac3_enc_channel_map
static const uint8_t ac3_enc_channel_map[8][2][6]
Table to remap channels from SMPTE order to AC-3 order.
Definition: ac3enc.c:200
audiodsp.h
mem.h
encode_exponents
static void encode_exponents(AC3EncodeContext *s)
Definition: ac3enc.c:804
flush_put_bits
static void flush_put_bits(PutBitContext *s)
Pad the end of the output stream with zeros.
Definition: put_bits.h:143
AV_CHANNEL_LAYOUT_MONO
#define AV_CHANNEL_LAYOUT_MONO
Definition: channel_layout.h:378
ff_ac3_bit_alloc_calc_mask
int ff_ac3_bit_alloc_calc_mask(AC3BitAllocParameters *s, int16_t *band_psd, int start, int end, int fast_gain, int is_lfe, int dba_mode, int dba_nsegs, uint8_t *dba_offsets, uint8_t *dba_lengths, uint8_t *dba_values, int16_t *mask)
Calculate the masking curve.
Definition: ac3.c:201
ff_ac3_slow_gain_tab
const uint16_t ff_ac3_slow_gain_tab[4]
Definition: ac3tab.c:134
AC3ENC_OPT_DSUREX_DPLIIZ
#define AC3ENC_OPT_DSUREX_DPLIIZ
Definition: ac3enc.h:78
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:472
AVPacket
This structure stores compressed data.
Definition: packet.h:501
ac3.h
AV_OPT_TYPE_BOOL
@ AV_OPT_TYPE_BOOL
Definition: opt.h:261
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
count_exponent_bits
static int count_exponent_bits(AC3EncodeContext *s)
Definition: ac3enc.c:854
ff_ac3_fast_gain_tab
const uint16_t ff_ac3_fast_gain_tab[8]
Definition: ac3tab.c:146
reset_block_bap
static void reset_block_bap(AC3EncodeContext *s)
Definition: ac3enc.c:1278
AC3ENC_OPT_NOT_INDICATED
#define AC3ENC_OPT_NOT_INDICATED
Definition: ac3enc.h:75
AV_CH_LAYOUT_4POINT0
#define AV_CH_LAYOUT_4POINT0
Definition: channel_layout.h:210
ff_ac3_encode_close
av_cold int ff_ac3_encode_close(AVCodecContext *avctx)
Finalize encoding and free any memory allocated by the encoder.
Definition: ac3enc.c:2158
AC3ENC_OPT_DOWNMIX_LTRT
#define AC3ENC_OPT_DOWNMIX_LTRT
Definition: ac3enc.h:83
int32_t
int32_t
Definition: audioconvert.c:56
AV_CHANNEL_LAYOUT_5POINT1_BACK
#define AV_CHANNEL_LAYOUT_5POINT1_BACK
Definition: channel_layout.h:391
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
EXP_D25
#define EXP_D25
Definition: ac3defs.h:42
cbr_bit_allocation
static int cbr_bit_allocation(AC3EncodeContext *s)
Definition: ac3enc.c:1402
block
The exact code depends on how similar the blocks are and how related they are to the block
Definition: filter_design.txt:207
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AC3EncOptions::surround_mix_level
float surround_mix_level
Definition: ac3enc.h:98
AC3ENC_OPT_MODE_ON
#define AC3ENC_OPT_MODE_ON
Definition: ac3enc.h:76
AV_CHANNEL_LAYOUT_5POINT0
#define AV_CHANNEL_LAYOUT_5POINT0
Definition: channel_layout.h:388
ac3tab.h
AC3EncOptions::extended_bsi_2
int extended_bsi_2
Definition: ac3enc.h:111
AC3Mant::qmant1_ptr
int16_t * qmant1_ptr
Definition: ac3enc.c:59
av_bswap16
#define av_bswap16
Definition: bswap.h:27
AV_CHANNEL_LAYOUT_5POINT1
#define AV_CHANNEL_LAYOUT_5POINT1
Definition: channel_layout.h:389
put_bits.h
AV_OPT_TYPE_CONST
@ AV_OPT_TYPE_CONST
Definition: opt.h:254
snprintf
#define snprintf
Definition: snprintf.h:34
AV_AUDIO_SERVICE_TYPE_MAIN
@ AV_AUDIO_SERVICE_TYPE_MAIN
Definition: defs.h:223
AV_CH_LAYOUT_2_2
#define AV_CH_LAYOUT_2_2
Definition: channel_layout.h:212
exponent_init
static av_cold void exponent_init(void)
Definition: ac3enc.c:616
validate_options
static av_cold int validate_options(AC3EncodeContext *s)
Definition: ac3enc.c:2215
AC3EncOptions::loro_center_mix_level
float loro_center_mix_level
Definition: ac3enc.h:109
ff_ac3_bit_alloc_calc_psd
void ff_ac3_bit_alloc_calc_psd(int8_t *exp, int start, int end, int16_t *psd, int16_t *band_psd)
Calculate the log power-spectral density of the input signal.
Definition: ac3.c:175
ff_eac3_default_cpl_band_struct
const uint8_t ff_eac3_default_cpl_band_struct[18]
Table E2.16 Default Coupling Banding Structure.
Definition: ac3tab.c:112
count_mantissa_bits_update_ch
static void count_mantissa_bits_update_ch(AC3EncodeContext *s, int ch, uint16_t mant_cnt[AC3_MAX_BLOCKS][16], int start, int end)
Update mantissa bit counts for all blocks in 1 channel in a given bandwidth range.
Definition: ac3enc.c:1325