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1 /*
2  * AC-3 encoder & E-AC-3 encoder common header
3  * Copyright (c) 2000 Fabrice Bellard
4  * Copyright (c) 2006-2010 Justin Ruggles <justin.ruggles@gmail.com>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
23 /**
24  * @file
25  * AC-3 encoder & E-AC-3 encoder common header
26  */
28 #ifndef AVCODEC_AC3ENC_H
29 #define AVCODEC_AC3ENC_H
31 #include <stdint.h>
33 #include "libavutil/float_dsp.h"
35 #include "ac3.h"
36 #include "ac3dsp.h"
37 #include "avcodec.h"
38 #include "fft.h"
39 #include "mathops.h"
40 #include "me_cmp.h"
41 #include "put_bits.h"
42 #include "audiodsp.h"
45 #define CONFIG_AC3ENC_FLOAT 0
46 #endif
48 #define OFFSET(param) offsetof(AC3EncodeContext, options.param)
51 #define AC3ENC_TYPE_AC3_FIXED 0
52 #define AC3ENC_TYPE_AC3 1
53 #define AC3ENC_TYPE_EAC3 2
56 #define AC3_NAME(x) ff_ac3_float_ ## x
57 #define MAC_COEF(d,a,b) ((d)+=(a)*(b))
58 #define COEF_MIN (-16777215.0/16777216.0)
59 #define COEF_MAX ( 16777215.0/16777216.0)
61 typedef float SampleType;
62 typedef float CoefType;
63 typedef float CoefSumType;
64 #else
65 #define AC3_NAME(x) ff_ac3_fixed_ ## x
66 #define MAC_COEF(d,a,b) MAC64(d,a,b)
67 #define COEF_MIN -16777215
68 #define COEF_MAX 16777215
69 #define NEW_CPL_COORD_THRESHOLD 503317
70 typedef int16_t SampleType;
71 typedef int32_t CoefType;
72 typedef int64_t CoefSumType;
73 #endif
75 /* common option values */
76 #define AC3ENC_OPT_NONE -1
77 #define AC3ENC_OPT_AUTO -1
78 #define AC3ENC_OPT_OFF 0
79 #define AC3ENC_OPT_ON 1
81 #define AC3ENC_OPT_MODE_ON 2
82 #define AC3ENC_OPT_MODE_OFF 1
85 /* specific option values */
86 #define AC3ENC_OPT_LARGE_ROOM 1
87 #define AC3ENC_OPT_SMALL_ROOM 2
90 #define AC3ENC_OPT_DOWNMIX_DPLII 3 // reserved value in A/52, but used by encoders to indicate DPL2
95 /**
96  * Encoding Options used by AVOption.
97  */
98 typedef struct AC3EncOptions {
99  /* AC-3 metadata options*/
109  int original;
123  /* other encoding options */
128 } AC3EncOptions;
130 /**
131  * Data for a single audio block.
132  */
133 typedef struct AC3Block {
134  CoefType **mdct_coef; ///< MDCT coefficients
135  int32_t **fixed_coef; ///< fixed-point MDCT coefficients
136  uint8_t **exp; ///< original exponents
137  uint8_t **grouped_exp; ///< grouped exponents
138  int16_t **psd; ///< psd per frequency bin
139  int16_t **band_psd; ///< psd per critical band
140  int16_t **mask; ///< masking curve
141  uint16_t **qmant; ///< quantized mantissas
142  uint8_t **cpl_coord_exp; ///< coupling coord exponents (cplcoexp)
143  uint8_t **cpl_coord_mant; ///< coupling coord mantissas (cplcomant)
144  uint8_t coeff_shift[AC3_MAX_CHANNELS]; ///< fixed-point coefficient shift values
145  uint8_t new_rematrixing_strategy; ///< send new rematrixing flags in this block
146  int num_rematrixing_bands; ///< number of rematrixing bands
147  uint8_t rematrixing_flags[4]; ///< rematrixing flags
148  int new_cpl_strategy; ///< send new coupling strategy
149  int cpl_in_use; ///< coupling in use for this block (cplinu)
150  uint8_t channel_in_cpl[AC3_MAX_CHANNELS]; ///< channel in coupling (chincpl)
151  int num_cpl_channels; ///< number of channels in coupling
152  uint8_t new_cpl_coords[AC3_MAX_CHANNELS]; ///< send new coupling coordinates (cplcoe)
153  uint8_t cpl_master_exp[AC3_MAX_CHANNELS]; ///< coupling coord master exponents (mstrcplco)
154  int new_snr_offsets; ///< send new SNR offsets
155  int new_cpl_leak; ///< send new coupling leak info
156  int end_freq[AC3_MAX_CHANNELS]; ///< end frequency bin (endmant)
157 } AC3Block;
159 /**
160  * AC-3 encoder private context.
161  */
162 typedef struct AC3EncodeContext {
163  AVClass *av_class; ///< AVClass used for AVOption
164  AC3EncOptions options; ///< encoding options
165  AVCodecContext *avctx; ///< parent AVCodecContext
166  PutBitContext pb; ///< bitstream writer context
170  AC3DSPContext ac3dsp; ///< AC-3 optimized functions
171  FFTContext mdct; ///< FFT context for MDCT calculation
172  const SampleType *mdct_window; ///< MDCT window function array
174  AC3Block blocks[AC3_MAX_BLOCKS]; ///< per-block info
176  int fixed_point; ///< indicates if fixed-point encoder is being used
177  int eac3; ///< indicates if this is E-AC-3 vs. AC-3
178  int bitstream_id; ///< bitstream id (bsid)
179  int bitstream_mode; ///< bitstream mode (bsmod)
181  int bit_rate; ///< target bit rate, in bits-per-second
182  int sample_rate; ///< sampling frequency, in Hz
184  int num_blks_code; ///< number of blocks code (numblkscod)
185  int num_blocks; ///< number of blocks per frame
186  int frame_size_min; ///< minimum frame size in case rounding is necessary
187  int frame_size; ///< current frame size in bytes
188  int frame_size_code; ///< frame size code (frmsizecod)
189  uint16_t crc_inv[2];
190  int64_t bits_written; ///< bit count (used to avg. bitrate)
191  int64_t samples_written; ///< sample count (used to avg. bitrate)
193  int fbw_channels; ///< number of full-bandwidth channels (nfchans)
194  int channels; ///< total number of channels (nchans)
195  int lfe_on; ///< indicates if there is an LFE channel (lfeon)
196  int lfe_channel; ///< channel index of the LFE channel
197  int has_center; ///< indicates if there is a center channel
198  int has_surround; ///< indicates if there are one or more surround channels
199  int channel_mode; ///< channel mode (acmod)
200  const uint8_t *channel_map; ///< channel map used to reorder channels
202  int center_mix_level; ///< center mix level code
203  int surround_mix_level; ///< surround mix level code
204  int ltrt_center_mix_level; ///< Lt/Rt center mix level code
205  int ltrt_surround_mix_level; ///< Lt/Rt surround mix level code
206  int loro_center_mix_level; ///< Lo/Ro center mix level code
207  int loro_surround_mix_level; ///< Lo/Ro surround mix level code
209  int cutoff; ///< user-specified cutoff frequency, in Hz
210  int bandwidth_code; ///< bandwidth code (0 to 60) (chbwcod)
211  int start_freq[AC3_MAX_CHANNELS]; ///< start frequency bin (strtmant)
212  int cpl_end_freq; ///< coupling channel end frequency bin
214  int cpl_on; ///< coupling turned on for this frame
215  int cpl_enabled; ///< coupling enabled for all frames
216  int num_cpl_subbands; ///< number of coupling subbands (ncplsubnd)
217  int num_cpl_bands; ///< number of coupling bands (ncplbnd)
218  uint8_t cpl_band_sizes[AC3_MAX_CPL_BANDS]; ///< number of coeffs in each coupling band
220  int rematrixing_enabled; ///< stereo rematrixing enabled
222  /* bitrate allocation control */
223  int slow_gain_code; ///< slow gain code (sgaincod)
224  int slow_decay_code; ///< slow decay code (sdcycod)
225  int fast_decay_code; ///< fast decay code (fdcycod)
226  int db_per_bit_code; ///< dB/bit code (dbpbcod)
227  int floor_code; ///< floor code (floorcod)
228  AC3BitAllocParameters bit_alloc; ///< bit allocation parameters
229  int coarse_snr_offset; ///< coarse SNR offsets (csnroffst)
230  int fast_gain_code[AC3_MAX_CHANNELS]; ///< fast gain codes (signal-to-mask ratio) (fgaincod)
231  int fine_snr_offset[AC3_MAX_CHANNELS]; ///< fine SNR offsets (fsnroffst)
232  int frame_bits_fixed; ///< number of non-coefficient bits for fixed parameters
233  int frame_bits; ///< all frame bits except exponents and mantissas
234  int exponent_bits; ///< number of bits used for exponents
244  int16_t *psd_buffer;
245  int16_t *band_psd_buffer;
246  int16_t *mask_buffer;
247  int16_t *qmant_buffer;
252  uint8_t frame_exp_strategy[AC3_MAX_CHANNELS]; ///< frame exp strategy index
253  int use_frame_exp_strategy; ///< indicates use of frame exp strategy
254  uint8_t exp_ref_block[AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]; ///< reference blocks for EXP_REUSE
255  uint8_t *ref_bap [AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]; ///< bit allocation pointers (bap)
256  int ref_bap_set; ///< indicates if ref_bap pointers have been set
258  /* fixed vs. float function pointers */
260  int (*mdct_init)(struct AC3EncodeContext *s);
262  /* fixed vs. float templated function pointers */
265  /* AC-3 vs. E-AC-3 function pointers */
270 extern const uint64_t ff_ac3_channel_layouts[19];
293 void ff_ac3_output_frame(AC3EncodeContext *s, unsigned char *frame);
296 /* prototypes for functions in ac3enc_fixed.c and ac3enc_float.c */
305 /* prototypes for functions in ac3enc_template.c */
311  const AVFrame *frame, int *got_packet_ptr);
313  const AVFrame *frame, int *got_packet_ptr);
315 #endif /* AVCODEC_AC3ENC_H */
uint8_t new_rematrixing_strategy
send new rematrixing flags in this block
Definition: ac3enc.h:145
uint8_t exp_strategy[AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]
exponent strategies
Definition: ac3enc.h:251
int eac3_mixing_metadata
Definition: ac3enc.h:120
const char * s
Definition: avisynth_c.h:631
AVFloatDSPContext * fdsp
Definition: ac3enc.h:168
int ff_ac3_encode_init(AVCodecContext *avctx)
Definition: ac3enc.c:2425
int dialogue_level
Definition: ac3enc.h:100
This structure describes decoded (raw) audio or video data.
Definition: frame.h:180
int db_per_bit_code
dB/bit code (dbpbcod)
Definition: ac3enc.h:226
int slow_decay_code
slow decay code (sdcycod)
Definition: ac3enc.h:224
Encoding Options used by AVOption.
Definition: ac3enc.h:98
int ff_ac3_fixed_allocate_sample_buffers(AC3EncodeContext *s)
float loro_surround_mix_level
Definition: ac3enc.h:115
int channel_coupling
Definition: ac3enc.h:126
int dolby_surround_ex_mode
Definition: ac3enc.h:117
uint8_t ** cpl_coord_exp
coupling coord exponents (cplcoexp)
Definition: ac3enc.h:142
int bandwidth_code
bandwidth code (0 to 60) (chbwcod)
Definition: ac3enc.h:210
uint8_t * grouped_exp_buffer
Definition: ac3enc.h:243
int16_t ** psd
psd per frequency bin
Definition: ac3enc.h:138
int frame_size_code
frame size code (frmsizecod)
Definition: ac3enc.h:188
void(* mdct_end)(struct AC3EncodeContext *s)
Definition: ac3enc.h:259
int frame_bits
all frame bits except exponents and mantissas
Definition: ac3enc.h:233
const uint64_t ff_ac3_channel_layouts[19]
List of supported channel layouts.
Definition: ac3enc.c:81
uint8_t ** cpl_coord_mant
coupling coord mantissas (cplcomant)
Definition: ac3enc.h:143
uint16_t ** qmant
quantized mantissas
Definition: ac3enc.h:141
int start_freq[AC3_MAX_CHANNELS]
start frequency bin (strtmant)
Definition: ac3enc.h:211
int ff_ac3_validate_metadata(AC3EncodeContext *s)
Validate metadata options as set by AVOption system.
Definition: ac3enc.c:1833
PutBitContext pb
bitstream writer context
Definition: ac3enc.h:166
int num_cpl_channels
number of channels in coupling
Definition: ac3enc.h:151
AC3BitAllocParameters bit_alloc
bit allocation parameters
Definition: ac3enc.h:228
int ff_ac3_float_allocate_sample_buffers(AC3EncodeContext *s)
float ltrt_surround_mix_level
Definition: ac3enc.h:113
int ff_ac3_float_encode_frame(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr)
int new_cpl_leak
send new coupling leak info
Definition: ac3enc.h:155
int rematrixing_enabled
stereo rematrixing enabled
Definition: ac3enc.h:220
int bitstream_mode
Definition: ac3enc.h:101
int ff_ac3_float_encode_init(AVCodecContext *avctx)
Definition: ac3enc_float.c:139
int channel_mode
channel mode (acmod)
Definition: ac3enc.h:199
int num_cpl_subbands
number of coupling subbands (ncplsubnd)
Definition: ac3enc.h:216
float surround_mix_level
Definition: ac3enc.h:103
int(* allocate_sample_buffers)(struct AC3EncodeContext *s)
Definition: ac3enc.h:263
uint8_t rematrixing_flags[4]
rematrixing flags
Definition: ac3enc.h:147
int fbw_channels
number of full-bandwidth channels (nfchans)
Definition: ac3enc.h:193
uint8_t new_cpl_coords[AC3_MAX_CHANNELS]
send new coupling coordinates (cplcoe)
Definition: ac3enc.h:152
int ff_ac3_compute_bit_allocation(AC3EncodeContext *s)
Definition: ac3enc.c:1146
uint8_t * bap1_buffer
Definition: ac3enc.h:239
int slow_gain_code
slow gain code (sgaincod)
Definition: ac3enc.h:223
static AVFrame * frame
uint8_t cpl_master_exp[AC3_MAX_CHANNELS]
coupling coord master exponents (mstrcplco)
Definition: ac3enc.h:153
uint8_t ** exp
original exponents
Definition: ac3enc.h:136
int num_rematrixing_bands
number of rematrixing bands
Definition: ac3enc.h:146
AC3DSPContext ac3dsp
AC-3 optimized functions.
Definition: ac3enc.h:170
int loro_center_mix_level
Lo/Ro center mix level code.
Definition: ac3enc.h:206
int num_cpl_bands
number of coupling bands (ncplbnd)
Definition: ac3enc.h:217
void ff_ac3_fixed_mdct_end(AC3EncodeContext *s)
int lfe_channel
channel index of the LFE channel
Definition: ac3enc.h:196
int ref_bap_set
indicates if ref_bap pointers have been set
Definition: ac3enc.h:256
void ff_ac3_quantize_mantissas(AC3EncodeContext *s)
Quantize mantissas using coefficients, exponents, and bit allocation pointers.
Definition: ac3enc.c:1300
int new_snr_offsets
send new SNR offsets
Definition: ac3enc.h:154
int64_t CoefSumType
Definition: ac3enc.h:72
int loro_surround_mix_level
Lo/Ro surround mix level code.
Definition: ac3enc.h:207
CoefType ** mdct_coef
MDCT coefficients.
Definition: ac3enc.h:134
uint8_t channel_in_cpl[AC3_MAX_CHANNELS]
channel in coupling (chincpl)
Definition: ac3enc.h:150
int eac3_info_metadata
Definition: ac3enc.h:121
int mixing_level
Definition: ac3enc.h:106
int num_blks_code
number of blocks code (numblkscod)
Definition: ac3enc.h:184
AC3EncOptions options
encoding options
Definition: ac3enc.h:164
int16_t ** band_psd
psd per critical band
Definition: ac3enc.h:139
AVClass * av_class
AVClass used for AVOption.
Definition: ac3enc.h:163
float ltrt_center_mix_level
Definition: ac3enc.h:112
int channels
total number of channels (nchans)
Definition: ac3enc.h:194
maximum number of channels, including coupling channel
Definition: ac3.h:31
int cpl_on
coupling turned on for this frame
Definition: ac3enc.h:214
uint16_t crc_inv[2]
Definition: ac3enc.h:189
int16_t * mask_buffer
Definition: ac3enc.h:246
int16_t * psd_buffer
Definition: ac3enc.h:244
int fixed_point
indicates if fixed-point encoder is being used
Definition: ac3enc.h:176
int ltrt_surround_mix_level
Lt/Rt surround mix level code.
Definition: ac3enc.h:205
int new_cpl_strategy
send new coupling strategy
Definition: ac3enc.h:148
int surround_mix_level
surround mix level code
Definition: ac3enc.h:203
int cpl_in_use
coupling in use for this block (cplinu)
Definition: ac3enc.h:149
int cpl_enabled
coupling enabled for all frames
Definition: ac3enc.h:215
int16_t SampleType
Definition: ac3enc.h:70
Data for a single audio block.
Definition: ac3enc.h:133
int(* mdct_init)(struct AC3EncodeContext *s)
Definition: ac3enc.h:260
int floor_code
floor code (floorcod)
Definition: ac3enc.h:227
int bitstream_mode
bitstream mode (bsmod)
Definition: ac3enc.h:179
int has_surround
indicates if there are one or more surround channels
Definition: ac3enc.h:198
Definition: fft.h:88
uint8_t frame_exp_strategy[AC3_MAX_CHANNELS]
frame exp strategy index
Definition: ac3enc.h:252
AudioDSPContext adsp
Definition: ac3enc.h:167
int eac3
indicates if this is E-AC-3 vs. AC-3
Definition: ac3enc.h:177
void ff_ac3_apply_rematrixing(AC3EncodeContext *s)
Apply stereo rematrixing to coefficients based on rematrixing flags.
Definition: ac3enc.c:272
float loro_center_mix_level
Definition: ac3enc.h:114
int ff_ac3_float_mdct_init(AC3EncodeContext *s)
Initialize MDCT tables.
Definition: ac3enc_float.c:67
int ad_converter_type
Definition: ac3enc.h:119
void ff_ac3_process_exponents(AC3EncodeContext *s)
Calculate final exponents from the supplied MDCT coefficients and exponent shift. ...
Definition: ac3enc.c:637
void ff_ac3_compute_coupling_strategy(AC3EncodeContext *s)
Set the initial coupling strategy parameters prior to coupling analysis.
Definition: ac3enc.c:201
int exponent_bits
number of bits used for exponents
Definition: ac3enc.h:234
int stereo_rematrixing
Definition: ac3enc.h:125
int coarse_snr_offset
coarse SNR offsets (csnroffst)
Definition: ac3enc.h:229
int16_t ** mask
masking curve
Definition: ac3enc.h:140
FFTContext mdct
FFT context for MDCT calculation.
Definition: ac3enc.h:171
const SampleType * mdct_window
MDCT window function array.
Definition: ac3enc.h:172
SampleType ** planar_samples
Definition: ac3enc.h:237
int fast_decay_code
fast decay code (fdcycod)
Definition: ac3enc.h:225
int16_t * qmant_buffer
Definition: ac3enc.h:247
void(* output_frame_header)(struct AC3EncodeContext *s)
Definition: ac3enc.h:266
uint8_t * ref_bap[AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]
bit allocation pointers (bap)
Definition: ac3enc.h:255
Libavcodec external API header.
int audio_production_info
Definition: ac3enc.h:105
int dolby_surround_mode
Definition: ac3enc.h:104
main external API structure.
Definition: avcodec.h:1639
int fast_gain_code[AC3_MAX_CHANNELS]
fast gain codes (signal-to-mask ratio) (fgaincod)
Definition: ac3enc.h:230
int sample_rate
sampling frequency, in Hz
Definition: ac3enc.h:182
CoefType * mdct_coef_buffer
Definition: ac3enc.h:240
int has_center
indicates if there is a center channel
Definition: ac3enc.h:197
int bit_rate
target bit rate, in bits-per-second
Definition: ac3enc.h:181
const uint8_t * channel_map
channel map used to reorder channels
Definition: ac3enc.h:200
uint8_t * exp_buffer
Definition: ac3enc.h:242
int frame_bits_fixed
number of non-coefficient bits for fixed parameters
Definition: ac3enc.h:232
int end_freq[AC3_MAX_CHANNELS]
end frequency bin (endmant)
Definition: ac3enc.h:156
Describe the class of an AVClass context structure.
Definition: log.h:67
int cpl_start
Definition: ac3enc.h:127
uint8_t * cpl_coord_exp_buffer
Definition: ac3enc.h:248
int ltrt_center_mix_level
Lt/Rt center mix level code.
Definition: ac3enc.h:204
int ff_ac3_fixed_encode_frame(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr)
int center_mix_level
center mix level code
Definition: ac3enc.h:202
#define AC3_MAX_BLOCKS
Definition: ac3.h:36
AC-3 encoder private context.
Definition: ac3enc.h:162
AC3Block blocks[AC3_MAX_BLOCKS]
per-block info
Definition: ac3enc.h:174
SampleType * windowed_samples
Definition: ac3enc.h:236
int preferred_stereo_downmix
Definition: ac3enc.h:111
int num_blocks
number of blocks per frame
Definition: ac3enc.h:185
void ff_ac3_output_frame(AC3EncodeContext *s, unsigned char *frame)
Write the frame to the output bitstream.
Definition: ac3enc.c:1661
int ff_ac3_encode_close(AVCodecContext *avctx)
Finalize encoding and free any memory allocated by the encoder.
Definition: ac3enc.c:2017
float center_mix_level
Definition: ac3enc.h:102
uint8_t coeff_shift[AC3_MAX_CHANNELS]
fixed-point coefficient shift values
Definition: ac3enc.h:144
int extended_bsi_2
Definition: ac3enc.h:116
int frame_size
current frame size in bytes
Definition: ac3enc.h:187
int room_type
Definition: ac3enc.h:107
uint8_t ** grouped_exp
grouped exponents
Definition: ac3enc.h:137
int cpl_end_freq
coupling channel end frequency bin
Definition: ac3enc.h:212
uint8_t cpl_band_sizes[AC3_MAX_CPL_BANDS]
number of coeffs in each coupling band
Definition: ac3enc.h:218
MECmpContext mecc
Definition: ac3enc.h:169
Definition: ac3.h:40
int64_t bits_written
bit count (used to avg. bitrate)
Definition: ac3enc.h:190
int bitstream_id
bitstream id (bsid)
Definition: ac3enc.h:178
int16_t * band_psd_buffer
Definition: ac3enc.h:245
int dolby_headphone_mode
Definition: ac3enc.h:118
AVCodecContext * avctx
parent AVCodecContext
Definition: ac3enc.h:165
uint8_t exp_ref_block[AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]
reference blocks for EXP_REUSE
Definition: ac3enc.h:254
int allow_per_frame_metadata
Definition: ac3enc.h:124
int original
Definition: ac3enc.h:109
uint8_t * bap_buffer
Definition: ac3enc.h:238
int frame_size_min
minimum frame size in case rounding is necessary
Definition: ac3enc.h:186
void ff_ac3_float_mdct_end(AC3EncodeContext *s)
Finalize MDCT and free allocated memory.
Definition: ac3enc_float.c:54
int64_t samples_written
sample count (used to avg. bitrate)
Definition: ac3enc.h:191
uint8_t * cpl_coord_mant_buffer
Definition: ac3enc.h:249
int use_frame_exp_strategy
indicates use of frame exp strategy
Definition: ac3enc.h:253
int ff_ac3_fixed_mdct_init(AC3EncodeContext *s)
int32_t CoefType
Definition: ac3enc.h:71
int cutoff
user-specified cutoff frequency, in Hz
Definition: ac3enc.h:209
void ff_ac3_adjust_frame_size(AC3EncodeContext *s)
Adjust the frame size to make the average bit rate match the target bit rate.
Definition: ac3enc.c:183
int lfe_on
indicates if there is an LFE channel (lfeon)
Definition: ac3enc.h:195
int fine_snr_offset[AC3_MAX_CHANNELS]
fine SNR offsets (fsnroffst)
Definition: ac3enc.h:231
This structure stores compressed data.
Definition: avcodec.h:1551
Common code between the AC-3 encoder and decoder.
int32_t * fixed_coef_buffer
Definition: ac3enc.h:241
int extended_bsi_1
Definition: ac3enc.h:110
void ff_ac3_group_exponents(AC3EncodeContext *s)
Group exponents.
Definition: ac3enc.c:579
int copyright
Definition: ac3enc.h:108
int32_t ** fixed_coef
fixed-point MDCT coefficients
Definition: ac3enc.h:135
bitstream writer API