FFmpeg
mpc8.c
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1 /*
2  * Musepack SV8 decoder
3  * Copyright (c) 2007 Konstantin Shishkov
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples
25  * divided into 32 subbands.
26  */
27 
29 #include "libavutil/lfg.h"
30 #include "libavutil/thread.h"
31 #include "avcodec.h"
32 #include "get_bits.h"
33 #include "internal.h"
34 #include "mpegaudiodsp.h"
35 
36 #include "mpc.h"
37 #include "mpc8data.h"
38 #include "mpc8huff.h"
39 
40 static VLC band_vlc, scfi_vlc[2], dscf_vlc[2], res_vlc[2];
41 static VLC q1_vlc, q2_vlc[2], q3_vlc[2], quant_vlc[4][2], q9up_vlc;
42 
43 static inline int mpc8_dec_base(GetBitContext *gb, int k, int n)
44 {
45  int len = mpc8_cnk_len[k-1][n-1] - 1;
46  int code = len ? get_bits_long(gb, len) : 0;
47 
48  if (code >= mpc8_cnk_lost[k-1][n-1])
49  code = ((code << 1) | get_bits1(gb)) - mpc8_cnk_lost[k-1][n-1];
50 
51  return code;
52 }
53 
54 static inline int mpc8_dec_enum(GetBitContext *gb, int k, int n)
55 {
56  int bits = 0;
57  const uint32_t * C = mpc8_cnk[k-1];
58  int code = mpc8_dec_base(gb, k, n);
59 
60  do {
61  n--;
62  if (code >= C[n]) {
63  bits |= 1U << n;
64  code -= C[n];
65  C -= 32;
66  k--;
67  }
68  } while(k > 0);
69 
70  return bits;
71 }
72 
73 static inline int mpc8_get_mod_golomb(GetBitContext *gb, int m)
74 {
75  if(mpc8_cnk_len[0][m] < 1) return 0;
76  return mpc8_dec_base(gb, 1, m+1);
77 }
78 
79 static int mpc8_get_mask(GetBitContext *gb, int size, int t)
80 {
81  int mask = 0;
82 
83  if(t && t != size)
84  mask = mpc8_dec_enum(gb, FFMIN(t, size - t), size);
85  if((t << 1) > size) mask = ~mask;
86 
87  return mask;
88 }
89 
90 static av_cold void build_vlc(VLC *vlc, unsigned *buf_offset,
91  const uint8_t codes_counts[16],
92  const uint8_t **syms, int offset)
93 {
94  static VLC_TYPE vlc_buf[9296][2];
95  uint8_t len[MPC8_MAX_VLC_SIZE];
96  unsigned num = 0;
97 
98  vlc->table = &vlc_buf[*buf_offset];
99  vlc->table_allocated = FF_ARRAY_ELEMS(vlc_buf) - *buf_offset;
100 
101  for (int i = 16; i > 0; i--)
102  for (unsigned tmp = num + codes_counts[i - 1]; num < tmp; num++)
103  len[num] = i;
104 
105  ff_init_vlc_from_lengths(vlc, FFMIN(len[0], 9), num, len, 1,
106  *syms, 1, 1, offset, INIT_VLC_STATIC_OVERLONG, NULL);
107  *buf_offset += vlc->table_size;
108  *syms += num;
109 }
110 
111 static av_cold void mpc8_init_static(void)
112 {
113  const uint8_t *q_syms = mpc8_q_syms, *bands_syms = mpc8_bands_syms;
114  const uint8_t *res_syms = mpc8_res_syms, *scfi_syms = mpc8_scfi_syms;
115  const uint8_t *dscf_syms = mpc8_dscf_syms;
116  unsigned offset = 0;
117 
118  build_vlc(&band_vlc, &offset, mpc8_bands_len_counts, &bands_syms, 0);
119 
120  build_vlc(&q1_vlc, &offset, mpc8_q1_len_counts, &q_syms, 0);
122 
123  for (int i = 0; i < 2; i++){
124  build_vlc(&scfi_vlc[i], &offset, mpc8_scfi_len_counts[i], &scfi_syms, 0);
125 
126  build_vlc(&dscf_vlc[i], &offset, mpc8_dscf_len_counts[i], &dscf_syms, 0);
127 
128  build_vlc(&res_vlc[i], &offset, mpc8_res_len_counts[i], &res_syms, 0);
129 
130  build_vlc(&q2_vlc[i], &offset, mpc8_q2_len_counts[i], &q_syms, 0);
132  &q_syms, -48 - 16 * i);
133  for (int j = 0; j < 4; j++)
135  &q_syms, -((8 << j) - 1));
136  }
138 }
139 
141 {
142  static AVOnce init_static_once = AV_ONCE_INIT;
143  MPCContext *c = avctx->priv_data;
144  GetBitContext gb;
145  int channels;
146 
147  if(avctx->extradata_size < 2){
148  av_log(avctx, AV_LOG_ERROR, "Too small extradata size (%i)!\n", avctx->extradata_size);
149  return -1;
150  }
151  memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
152  av_lfg_init(&c->rnd, 0xDEADBEEF);
153  ff_mpadsp_init(&c->mpadsp);
154 
155  init_get_bits(&gb, avctx->extradata, 16);
156 
157  skip_bits(&gb, 3);//sample rate
158  c->maxbands = get_bits(&gb, 5) + 1;
159  if (c->maxbands >= BANDS) {
160  av_log(avctx,AV_LOG_ERROR, "maxbands %d too high\n", c->maxbands);
161  return AVERROR_INVALIDDATA;
162  }
163  channels = get_bits(&gb, 4) + 1;
164  if (channels > 2) {
165  avpriv_request_sample(avctx, "Multichannel MPC SV8");
166  return AVERROR_PATCHWELCOME;
167  }
168  c->MSS = get_bits1(&gb);
169  c->frames = 1 << (get_bits(&gb, 3) * 2);
170 
173  avctx->channels = channels;
174 
175  ff_thread_once(&init_static_once, mpc8_init_static);
176 
177  return 0;
178 }
179 
180 static int mpc8_decode_frame(AVCodecContext * avctx, void *data,
181  int *got_frame_ptr, AVPacket *avpkt)
182 {
183  AVFrame *frame = data;
184  const uint8_t *buf = avpkt->data;
185  int buf_size = avpkt->size;
186  MPCContext *c = avctx->priv_data;
187  GetBitContext gb2, *gb = &gb2;
188  int i, j, k, ch, cnt, res, t;
189  Band *bands = c->bands;
190  int off;
191  int maxband, keyframe;
192  int last[2];
193 
194  keyframe = c->cur_frame == 0;
195 
196  if(keyframe){
197  memset(c->Q, 0, sizeof(c->Q));
198  c->last_bits_used = 0;
199  }
200  if ((res = init_get_bits8(gb, buf, buf_size)) < 0)
201  return res;
202 
203  skip_bits(gb, c->last_bits_used & 7);
204 
205  if(keyframe)
206  maxband = mpc8_get_mod_golomb(gb, c->maxbands + 1);
207  else{
208  maxband = c->last_max_band + get_vlc2(gb, band_vlc.table, MPC8_BANDS_BITS, 2);
209  if(maxband > 32) maxband -= 33;
210  }
211 
212  if (get_bits_left(gb) < 0) {
213  *got_frame_ptr = 0;
214  return buf_size;
215  }
216 
217  if(maxband > c->maxbands + 1) {
218  av_log(avctx, AV_LOG_ERROR, "maxband %d too large\n",maxband);
219  return AVERROR_INVALIDDATA;
220  }
221  c->last_max_band = maxband;
222 
223  /* read subband indexes */
224  if(maxband){
225  last[0] = last[1] = 0;
226  for(i = maxband - 1; i >= 0; i--){
227  for(ch = 0; ch < 2; ch++){
228  last[ch] = get_vlc2(gb, res_vlc[last[ch] > 2].table, MPC8_RES_BITS, 2) + last[ch];
229  if(last[ch] > 15) last[ch] -= 17;
230  bands[i].res[ch] = last[ch];
231  }
232  }
233  if(c->MSS){
234  int mask;
235 
236  cnt = 0;
237  for(i = 0; i < maxband; i++)
238  if(bands[i].res[0] || bands[i].res[1])
239  cnt++;
240  t = mpc8_get_mod_golomb(gb, cnt);
241  mask = mpc8_get_mask(gb, cnt, t);
242  for(i = maxband - 1; i >= 0; i--)
243  if(bands[i].res[0] || bands[i].res[1]){
244  bands[i].msf = mask & 1;
245  mask >>= 1;
246  }
247  }
248  }
249  for(i = maxband; i < c->maxbands; i++)
250  bands[i].res[0] = bands[i].res[1] = 0;
251 
252  if(keyframe){
253  for(i = 0; i < 32; i++)
254  c->oldDSCF[0][i] = c->oldDSCF[1][i] = 1;
255  }
256 
257  for(i = 0; i < maxband; i++){
258  if(bands[i].res[0] || bands[i].res[1]){
259  cnt = !!bands[i].res[0] + !!bands[i].res[1] - 1;
260  if(cnt >= 0){
261  t = get_vlc2(gb, scfi_vlc[cnt].table, scfi_vlc[cnt].bits, 1);
262  if(bands[i].res[0]) bands[i].scfi[0] = t >> (2 * cnt);
263  if(bands[i].res[1]) bands[i].scfi[1] = t & 3;
264  }
265  }
266  }
267 
268  for(i = 0; i < maxband; i++){
269  for(ch = 0; ch < 2; ch++){
270  if(!bands[i].res[ch]) continue;
271 
272  if(c->oldDSCF[ch][i]){
273  bands[i].scf_idx[ch][0] = get_bits(gb, 7) - 6;
274  c->oldDSCF[ch][i] = 0;
275  }else{
276  t = get_vlc2(gb, dscf_vlc[1].table, MPC8_DSCF1_BITS, 2);
277  if(t == 64)
278  t += get_bits(gb, 6);
279  bands[i].scf_idx[ch][0] = ((bands[i].scf_idx[ch][2] + t - 25) & 0x7F) - 6;
280  }
281  for(j = 0; j < 2; j++){
282  if((bands[i].scfi[ch] << j) & 2)
283  bands[i].scf_idx[ch][j + 1] = bands[i].scf_idx[ch][j];
284  else{
285  t = get_vlc2(gb, dscf_vlc[0].table, MPC8_DSCF0_BITS, 2);
286  if(t == 31)
287  t = 64 + get_bits(gb, 6);
288  bands[i].scf_idx[ch][j + 1] = ((bands[i].scf_idx[ch][j] + t - 25) & 0x7F) - 6;
289  }
290  }
291  }
292  }
293 
294  for(i = 0, off = 0; i < maxband; i++, off += SAMPLES_PER_BAND){
295  for(ch = 0; ch < 2; ch++){
296  res = bands[i].res[ch];
297  switch(res){
298  case -1:
299  for(j = 0; j < SAMPLES_PER_BAND; j++)
300  c->Q[ch][off + j] = (av_lfg_get(&c->rnd) & 0x3FC) - 510;
301  break;
302  case 0:
303  break;
304  case 1:
305  for(j = 0; j < SAMPLES_PER_BAND; j += SAMPLES_PER_BAND / 2){
306  cnt = get_vlc2(gb, q1_vlc.table, MPC8_Q1_BITS, 2);
307  t = mpc8_get_mask(gb, 18, cnt);
308  for(k = 0; k < SAMPLES_PER_BAND / 2; k++)
309  c->Q[ch][off + j + k] = t & (1 << (SAMPLES_PER_BAND / 2 - k - 1))
310  ? (get_bits1(gb) << 1) - 1 : 0;
311  }
312  break;
313  case 2:
314  cnt = 6;//2*mpc8_thres[res]
315  for(j = 0; j < SAMPLES_PER_BAND; j += 3){
316  t = get_vlc2(gb, q2_vlc[cnt > 3].table, MPC8_Q2_BITS, 2);
317  c->Q[ch][off + j + 0] = mpc8_idx50[t];
318  c->Q[ch][off + j + 1] = mpc8_idx51[t];
319  c->Q[ch][off + j + 2] = mpc8_idx52[t];
320  cnt = (cnt >> 1) + mpc8_huffq2[t];
321  }
322  break;
323  case 3:
324  case 4:
325  for(j = 0; j < SAMPLES_PER_BAND; j += 2){
326  t = get_vlc2(gb, q3_vlc[res - 3].table, MPC8_Q3_BITS, 2);
327  c->Q[ch][off + j + 1] = t >> 4;
328  c->Q[ch][off + j + 0] = sign_extend(t, 4);
329  }
330  break;
331  case 5:
332  case 6:
333  case 7:
334  case 8:
335  cnt = 2 * mpc8_thres[res];
336  for(j = 0; j < SAMPLES_PER_BAND; j++){
337  const VLC *vlc = &quant_vlc[res - 5][cnt > mpc8_thres[res]];
338  c->Q[ch][off + j] = get_vlc2(gb, vlc->table, vlc->bits, 2);
339  cnt = (cnt >> 1) + FFABS(c->Q[ch][off + j]);
340  }
341  break;
342  default:
343  for(j = 0; j < SAMPLES_PER_BAND; j++){
344  c->Q[ch][off + j] = get_vlc2(gb, q9up_vlc.table, MPC8_Q9UP_BITS, 2);
345  if(res != 9){
346  c->Q[ch][off + j] <<= res - 9;
347  c->Q[ch][off + j] |= get_bits(gb, res - 9);
348  }
349  c->Q[ch][off + j] -= (1 << (res - 2)) - 1;
350  }
351  }
352  }
353  }
354 
355  frame->nb_samples = MPC_FRAME_SIZE;
356  if ((res = ff_get_buffer(avctx, frame, 0)) < 0)
357  return res;
358 
359  ff_mpc_dequantize_and_synth(c, maxband - 1,
360  (int16_t **)frame->extended_data,
361  avctx->channels);
362 
363  c->cur_frame++;
364 
365  c->last_bits_used = get_bits_count(gb);
366  if(c->cur_frame >= c->frames)
367  c->cur_frame = 0;
368  if (get_bits_left(gb) < 0) {
369  av_log(avctx, AV_LOG_ERROR, "Overread %d\n", -get_bits_left(gb));
370  c->last_bits_used = buf_size << 3;
371  } else if (c->cur_frame == 0 && get_bits_left(gb) < 8) {// we have only padding left
372  c->last_bits_used = buf_size << 3;
373  }
374 
375  *got_frame_ptr = 1;
376 
377  return c->cur_frame ? c->last_bits_used >> 3 : buf_size;
378 }
379 
381 {
382  MPCContext *c = avctx->priv_data;
383  c->cur_frame = 0;
384 }
385 
387  .name = "mpc8",
388  .long_name = NULL_IF_CONFIG_SMALL("Musepack SV8"),
389  .type = AVMEDIA_TYPE_AUDIO,
390  .id = AV_CODEC_ID_MUSEPACK8,
391  .priv_data_size = sizeof(MPCContext),
396  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
398  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
399 };
mpc8_init_static
static av_cold void mpc8_init_static(void)
Definition: mpc8.c:111
q1_vlc
static VLC q1_vlc
Definition: mpc8.c:41
MPC8_Q9UP_BITS
#define MPC8_Q9UP_BITS
Definition: mpc8huff.h:93
AVCodec
AVCodec.
Definition: codec.h:202
FF_CODEC_CAP_INIT_THREADSAFE
#define FF_CODEC_CAP_INIT_THREADSAFE
The codec does not modify any global variables in the init function, allowing to call the init functi...
Definition: internal.h:42
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
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static int get_bits_left(GetBitContext *gb)
Definition: get_bits.h:850
mpc8data.h
AVCodecContext::channel_layout
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:1043
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av_cold void av_lfg_init(AVLFG *c, unsigned int seed)
Definition: lfg.c:32
sample_fmts
static enum AVSampleFormat sample_fmts[]
Definition: adpcmenc.c:948
thread.h
mpc8_decode_flush
static av_cold void mpc8_decode_flush(AVCodecContext *avctx)
Definition: mpc8.c:380
AV_CH_LAYOUT_MONO
#define AV_CH_LAYOUT_MONO
Definition: channel_layout.h:90
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static unsigned int get_bits_long(GetBitContext *s, int n)
Read 0-32 bits.
Definition: get_bits.h:547
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static const uint8_t mpc8_dscf_len_counts[2][16]
Definition: mpc8huff.h:68
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static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:220
ff_mpadsp_init
av_cold void ff_mpadsp_init(MPADSPContext *s)
Definition: mpegaudiodsp.c:81
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static int mpc8_dec_base(GetBitContext *gb, int k, int n)
Definition: mpc8.c:43
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:310
tmp
static uint8_t tmp[11]
Definition: aes_ctr.c:26
internal.h
AVPacket::data
uint8_t * data
Definition: packet.h:373
table
static const uint16_t table[]
Definition: prosumer.c:206
data
const char data[16]
Definition: mxf.c:143
MPCContext
Definition: mpc.h:54
scfi_vlc
static VLC scfi_vlc[2]
Definition: mpc8.c:40
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static av_always_inline int get_vlc2(GetBitContext *s, VLC_TYPE(*table)[2], int bits, int max_depth)
Parse a vlc code.
Definition: get_bits.h:798
init_get_bits
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:660
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static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:468
mpc8huff.h
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static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:380
build_vlc
static av_cold void build_vlc(VLC *vlc, unsigned *buf_offset, const uint8_t codes_counts[16], const uint8_t **syms, int offset)
Definition: mpc8.c:90
VLC_TYPE
#define VLC_TYPE
Definition: vlc.h:24
U
#define U(x)
Definition: vp56_arith.h:37
MPC8_RES_BITS
#define MPC8_RES_BITS
Definition: mpc8huff.h:73
mpc8_get_mod_golomb
static int mpc8_get_mod_golomb(GetBitContext *gb, int m)
Definition: mpc8.c:73
GetBitContext
Definition: get_bits.h:62
mpc8_get_mask
static int mpc8_get_mask(GetBitContext *gb, int size, int t)
Definition: mpc8.c:79
ff_mpc_dequantize_and_synth
void ff_mpc_dequantize_and_synth(MPCContext *c, int maxband, int16_t **out, int channels)
Definition: mpc.c:55
ff_mpc8_decoder
const AVCodec ff_mpc8_decoder
Definition: mpc8.c:386
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static const uint8_t mpc8_q2_len_counts[2][16]
Definition: mpc8huff.h:101
mpc8_scfi_len_counts
static const uint8_t mpc8_scfi_len_counts[2][16]
Definition: mpc8huff.h:47
AV_CH_LAYOUT_STEREO
#define AV_CH_LAYOUT_STEREO
Definition: channel_layout.h:91
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static const uint32_t mpc8_cnk_lost[16][33]
Definition: mpc8data.h:101
mpc8_cnk_len
static const uint8_t mpc8_cnk_len[16][33]
Definition: mpc8data.h:80
ff_init_vlc_from_lengths
int ff_init_vlc_from_lengths(VLC *vlc_arg, int nb_bits, int nb_codes, const int8_t *lens, int lens_wrap, const void *symbols, int symbols_wrap, int symbols_size, int offset, int flags, void *logctx)
Build VLC decoding tables suitable for use with get_vlc2()
Definition: bitstream.c:381
C
s EdgeDetect Foobar g libavfilter vf_edgedetect c libavfilter vf_foobar c edit libavfilter and add an entry for foobar following the pattern of the other filters edit libavfilter allfilters and add an entry for foobar following the pattern of the other filters configure make j< whatever > ffmpeg ffmpeg i you should get a foobar png with Lena edge detected That s your new playground is ready Some little details about what s going which in turn will define variables for the build system and the C
Definition: writing_filters.txt:58
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Definition: mpc8huff.h:114
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Definition: thread.h:175
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#define AV_LOG_ERROR
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Definition: log.h:180
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Definition: attributes.h:90
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static int init_get_bits8(GetBitContext *s, const uint8_t *buffer, int byte_size)
Initialize GetBitContext.
Definition: get_bits.h:678
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Definition: decode_audio.c:71
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static unsigned int av_lfg_get(AVLFG *c)
Get the next random unsigned 32-bit number using an ALFG.
Definition: lfg.h:53
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Definition: avutil.h:202
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Definition: mpc8data.h:41
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Definition: mpc8.c:180
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Definition: common.h:65
MPC8_Q1_BITS
#define MPC8_Q1_BITS
Definition: mpc8huff.h:87
mpc.h
AV_ONCE_INIT
#define AV_ONCE_INIT
Definition: thread.h:173
mpc8_bands_len_counts
static const uint8_t mpc8_bands_len_counts[16]
Definition: mpc8huff.h:36
mpc8_q1_len_counts
static const uint8_t mpc8_q1_len_counts[16]
Definition: mpc8huff.h:89
flush
static void flush(AVCodecContext *avctx)
Definition: aacdec_template.c:593
NULL
#define NULL
Definition: coverity.c:32
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
ff_mpa_synth_init_fixed
void ff_mpa_synth_init_fixed(void)
MPC_FRAME_SIZE
#define MPC_FRAME_SIZE
Definition: mpc.h:43
get_bits1
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:499
mpc8_huffq2
static const int8_t mpc8_huffq2[5 *5 *5]
Definition: mpc8data.h:50
quant_vlc
static VLC quant_vlc[4][2]
Definition: mpc8.c:41
AVOnce
#define AVOnce
Definition: thread.h:172
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
AV_CODEC_CAP_CHANNEL_CONF
#define AV_CODEC_CAP_CHANNEL_CONF
Codec should fill in channel configuration and samplerate instead of container.
Definition: codec.h:109
VLC::table_allocated
int table_allocated
Definition: vlc.h:29
mpc8_q34_len_counts
static const uint8_t mpc8_q34_len_counts[2][16]
Definition: mpc8huff.h:109
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1651
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
MPC8_Q3_BITS
#define MPC8_Q3_BITS
Definition: mpc8huff.h:106
AVPacket::size
int size
Definition: packet.h:374
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
mpc8_thres
static const unsigned int mpc8_thres[]
Definition: mpc8data.h:49
mpc8_bands_syms
static const uint8_t mpc8_bands_syms[MPC8_BANDS_SIZE]
Definition: mpc8huff.h:32
mpc8_q_syms
static const uint8_t mpc8_q_syms[]
Definition: mpc8huff.h:129
band_vlc
static VLC band_vlc
Definition: mpc8.c:40
SAMPLES_PER_BAND
#define SAMPLES_PER_BAND
Definition: mpc.h:42
AVCodecContext::sample_fmt
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1000
AV_SAMPLE_FMT_NONE
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:59
size
int size
Definition: twinvq_data.h:10344
MPC8_Q2_BITS
#define MPC8_Q2_BITS
Definition: mpc8huff.h:99
offset
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
Definition: writing_filters.txt:86
mpc8_cnk
static const uint32_t mpc8_cnk[16][32]
Definition: mpc8data.h:60
AV_SAMPLE_FMT_S16P
@ AV_SAMPLE_FMT_S16P
signed 16 bits, planar
Definition: samplefmt.h:67
AVCodecContext::channels
int channels
number of audio channels
Definition: avcodec.h:993
q9up_vlc
static VLC q9up_vlc
Definition: mpc8.c:41
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
code
and forward the test the status of outputs and forward it to the corresponding return FFERROR_NOT_READY If the filters stores internally one or a few frame for some it can consider them to be part of the FIFO and delay acknowledging a status change accordingly Example code
Definition: filter_design.txt:178
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:484
BANDS
#define BANDS
Definition: imc.c:55
mpc8_res_syms
static const uint8_t mpc8_res_syms[]
Definition: mpc8huff.h:75
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
mpc8_dec_enum
static int mpc8_dec_enum(GetBitContext *gb, int k, int n)
Definition: mpc8.c:54
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
mpc8_dscf_syms
static const uint8_t mpc8_dscf_syms[]
Definition: mpc8huff.h:55
MPC8_DSCF1_BITS
#define MPC8_DSCF1_BITS
Definition: mpc8huff.h:53
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:209
len
int len
Definition: vorbis_enc_data.h:426
res_vlc
static VLC res_vlc[2]
Definition: mpc8.c:40
avcodec.h
q3_vlc
static VLC q3_vlc[2]
Definition: mpc8.c:41
VLC::bits
int bits
Definition: vlc.h:27
INIT_VLC_STATIC_OVERLONG
#define INIT_VLC_STATIC_OVERLONG
Definition: vlc.h:96
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_CODEC_ID_MUSEPACK8
@ AV_CODEC_ID_MUSEPACK8
Definition: codec_id.h:457
dscf_vlc
static VLC dscf_vlc[2]
Definition: mpc8.c:40
mpc8_decode_init
static av_cold int mpc8_decode_init(AVCodecContext *avctx)
Definition: mpc8.c:140
vlc_buf
static VLC_TYPE vlc_buf[16716][2]
Definition: clearvideo.c:86
AVCodecContext
main external API structure.
Definition: avcodec.h:383
mpc8_res_len_counts
static const uint8_t mpc8_res_len_counts[2][16]
Definition: mpc8huff.h:82
channel_layout.h
Band
Subband structure - hold all variables for each subband.
Definition: mpc.h:46
mpc8_idx50
static const int8_t mpc8_idx50[125]
Definition: mpc8data.h:27
MPC8_DSCF0_BITS
#define MPC8_DSCF0_BITS
Definition: mpc8huff.h:52
VLC
Definition: vlc.h:26
MPC8_BANDS_BITS
#define MPC8_BANDS_BITS
Definition: mpc8huff.h:30
sign_extend
static av_const int sign_extend(int val, unsigned bits)
Definition: mathops.h:130
mpc8_q9up_len_counts
static const uint8_t mpc8_q9up_len_counts[16]
Definition: mpc8huff.h:95
VLC::table_size
int table_size
Definition: vlc.h:29
mpegaudiodsp.h
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:37
AVPacket
This structure stores compressed data.
Definition: packet.h:350
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:410
MPC8_MAX_VLC_SIZE
#define MPC8_MAX_VLC_SIZE
Definition: mpc8huff.h:27
mpc8_scfi_syms
static const uint8_t mpc8_scfi_syms[]
Definition: mpc8huff.h:40
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
mpc8_idx51
static const int8_t mpc8_idx51[125]
Definition: mpc8data.h:34
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
VLC::table
VLC_TYPE(* table)[2]
code, bits
Definition: vlc.h:28
q2_vlc
static VLC q2_vlc[2]
Definition: mpc8.c:41