FFmpeg  4.4.6
ac3enc.c
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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"
33 #include "libavutil/avstring.h"
35 #include "libavutil/crc.h"
36 #include "libavutil/internal.h"
37 #include "libavutil/mem_internal.h"
38 #include "libavutil/opt.h"
39 #include "libavutil/thread.h"
40 #include "avcodec.h"
41 #include "internal.h"
42 #include "me_cmp.h"
43 #include "put_bits.h"
44 #include "audiodsp.h"
45 #include "ac3dsp.h"
46 #include "ac3.h"
47 #include "fft.h"
48 #include "ac3enc.h"
49 #include "eac3enc.h"
50 
51 typedef struct AC3Mant {
52  int16_t *qmant1_ptr, *qmant2_ptr, *qmant4_ptr; ///< mantissa pointers for bap=1,2,4
53  int mant1_cnt, mant2_cnt, mant4_cnt; ///< mantissa counts for bap=1,2,4
54 } AC3Mant;
55 
56 #define CMIXLEV_NUM_OPTIONS 3
57 static const float cmixlev_options[CMIXLEV_NUM_OPTIONS] = {
59 };
60 
61 #define SURMIXLEV_NUM_OPTIONS 3
64 };
65 
66 #define EXTMIXLEV_NUM_OPTIONS 8
70 };
71 
72 /* The first two options apply only to the AC-3 encoders;
73  * the rest is also valid for EAC-3. When modifying it,
74  * it might be necessary to adapt said offset in eac3enc.c. */
75 #define OFFSET(param) offsetof(AC3EncodeContext, options.param)
76 #define AC3ENC_PARAM (AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM)
78 /* AC-3 downmix levels */
79 {"center_mixlev", "Center Mix Level", OFFSET(center_mix_level), AV_OPT_TYPE_FLOAT, {.dbl = LEVEL_MINUS_4POINT5DB }, 0.0, 1.0, AC3ENC_PARAM},
80 {"surround_mixlev", "Surround Mix Level", OFFSET(surround_mix_level), AV_OPT_TYPE_FLOAT, {.dbl = LEVEL_MINUS_6DB }, 0.0, 1.0, AC3ENC_PARAM},
81 /* audio production information */
82 {"mixing_level", "Mixing Level", OFFSET(mixing_level), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, 111, AC3ENC_PARAM},
83 {"room_type", "Room Type", OFFSET(room_type), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, AC3ENC_OPT_SMALL_ROOM, AC3ENC_PARAM, "room_type"},
84  {"notindicated", "Not Indicated (default)", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_NOT_INDICATED }, INT_MIN, INT_MAX, AC3ENC_PARAM, "room_type"},
85  {"large", "Large Room", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_LARGE_ROOM }, INT_MIN, INT_MAX, AC3ENC_PARAM, "room_type"},
86  {"small", "Small Room", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_SMALL_ROOM }, INT_MIN, INT_MAX, AC3ENC_PARAM, "room_type"},
87 /* Metadata Options */
88 {"per_frame_metadata", "Allow Changing Metadata Per-Frame", OFFSET(allow_per_frame_metadata), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, AC3ENC_PARAM},
89 {"copyright", "Copyright Bit", OFFSET(copyright), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, 1, AC3ENC_PARAM},
90 {"dialnorm", "Dialogue Level (dB)", OFFSET(dialogue_level), AV_OPT_TYPE_INT, {.i64 = -31 }, -31, -1, AC3ENC_PARAM},
91 {"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, "dsur_mode"},
92  {"notindicated", "Not Indicated (default)", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_NOT_INDICATED }, INT_MIN, INT_MAX, AC3ENC_PARAM, "dsur_mode"},
93  {"on", "Dolby Surround Encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_MODE_ON }, INT_MIN, INT_MAX, AC3ENC_PARAM, "dsur_mode"},
94  {"off", "Not Dolby Surround Encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_MODE_OFF }, INT_MIN, INT_MAX, AC3ENC_PARAM, "dsur_mode"},
95 {"original", "Original Bit Stream", OFFSET(original), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, 1, AC3ENC_PARAM},
96 /* extended bitstream information */
97 {"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, "dmix_mode"},
98  {"notindicated", "Not Indicated (default)", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_NOT_INDICATED }, INT_MIN, INT_MAX, AC3ENC_PARAM, "dmix_mode"},
99  {"ltrt", "Lt/Rt Downmix Preferred", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_DOWNMIX_LTRT }, INT_MIN, INT_MAX, AC3ENC_PARAM, "dmix_mode"},
100  {"loro", "Lo/Ro Downmix Preferred", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_DOWNMIX_LORO }, INT_MIN, INT_MAX, AC3ENC_PARAM, "dmix_mode"},
101  {"dplii", "Dolby Pro Logic II Downmix Preferred", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_DOWNMIX_DPLII }, INT_MIN, INT_MAX, AC3ENC_PARAM, "dmix_mode"},
102 {"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},
103 {"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},
104 {"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},
105 {"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},
106 {"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, "dsurex_mode"},
107  {"notindicated", "Not Indicated (default)", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_NOT_INDICATED }, INT_MIN, INT_MAX, AC3ENC_PARAM, "dsurex_mode"},
108  {"on", "Dolby Surround EX Encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_MODE_ON }, INT_MIN, INT_MAX, AC3ENC_PARAM, "dsurex_mode"},
109  {"off", "Not Dolby Surround EX Encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_MODE_OFF }, INT_MIN, INT_MAX, AC3ENC_PARAM, "dsurex_mode"},
110  {"dpliiz", "Dolby Pro Logic IIz-encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_DSUREX_DPLIIZ }, INT_MIN, INT_MAX, AC3ENC_PARAM, "dsurex_mode"},
111 {"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, "dheadphone_mode"},
112  {"notindicated", "Not Indicated (default)", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_NOT_INDICATED }, INT_MIN, INT_MAX, AC3ENC_PARAM, "dheadphone_mode"},
113  {"on", "Dolby Headphone Encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_MODE_ON }, INT_MIN, INT_MAX, AC3ENC_PARAM, "dheadphone_mode"},
114  {"off", "Not Dolby Headphone Encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_MODE_OFF }, INT_MIN, INT_MAX, AC3ENC_PARAM, "dheadphone_mode"},
115 {"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, "ad_conv_type"},
116  {"standard", "Standard (default)", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_ADCONV_STANDARD }, INT_MIN, INT_MAX, AC3ENC_PARAM, "ad_conv_type"},
117  {"hdcd", "HDCD", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_ADCONV_HDCD }, INT_MIN, INT_MAX, AC3ENC_PARAM, "ad_conv_type"},
118 /* Other Encoding Options */
119 {"stereo_rematrixing", "Stereo Rematrixing", OFFSET(stereo_rematrixing), AV_OPT_TYPE_BOOL, {.i64 = 1 }, 0, 1, AC3ENC_PARAM},
120 {"channel_coupling", "Channel Coupling", OFFSET(channel_coupling), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_AUTO }, AC3ENC_OPT_AUTO, AC3ENC_OPT_ON, AC3ENC_PARAM, "channel_coupling"},
121  {"auto", "Selected by the Encoder", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_AUTO }, INT_MIN, INT_MAX, AC3ENC_PARAM, "channel_coupling"},
122 {"cpl_start_band", "Coupling Start Band", OFFSET(cpl_start), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_AUTO }, AC3ENC_OPT_AUTO, 15, AC3ENC_PARAM, "cpl_start_band"},
123  {"auto", "Selected by the Encoder", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_AUTO }, INT_MIN, INT_MAX, AC3ENC_PARAM, "cpl_start_band"},
124 {NULL}
125 };
126 
128  { "b", "0" },
129  { NULL }
130 };
131 
132 /**
133  * LUT for number of exponent groups.
134  * exponent_group_tab[coupling][exponent strategy-1][number of coefficients]
135  */
136 static uint8_t exponent_group_tab[2][3][256];
137 
138 
139 /**
140  * List of supported channel layouts.
141  */
142 const uint64_t ff_ac3_channel_layouts[19] = {
161  0
162 };
163 
164 /**
165  * Table to remap channels from SMPTE order to AC-3 order.
166  * [channel_mode][lfe][ch]
167  */
168 static const uint8_t ac3_enc_channel_map[8][2][6] = {
170  { { 0, 1, 2, 3, }, { 0, 1, 3, 4, 2, } },
171  { { 0, 2, 1, 3, 4, }, { 0, 2, 1, 4, 5, 3 } },
172 };
173 
174 /**
175  * LUT to select the bandwidth code based on the bit rate, sample rate, and
176  * number of full-bandwidth channels.
177  * bandwidth_tab[fbw_channels-1][sample rate code][bit rate code]
178  */
179 static const uint8_t ac3_bandwidth_tab[5][3][19] = {
180 // 32 40 48 56 64 80 96 112 128 160 192 224 256 320 384 448 512 576 640
181 
182  { { 0, 0, 0, 12, 16, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48 },
183  { 0, 0, 0, 16, 20, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56 },
184  { 0, 0, 0, 32, 40, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } },
185 
186  { { 0, 0, 0, 0, 0, 0, 0, 20, 24, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48 },
187  { 0, 0, 0, 0, 0, 0, 4, 24, 28, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56 },
188  { 0, 0, 0, 0, 0, 0, 20, 44, 52, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } },
189 
190  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 24, 32, 40, 48, 48, 48, 48, 48, 48 },
191  { 0, 0, 0, 0, 0, 0, 0, 0, 4, 20, 28, 36, 44, 56, 56, 56, 56, 56, 56 },
192  { 0, 0, 0, 0, 0, 0, 0, 0, 20, 40, 48, 60, 60, 60, 60, 60, 60, 60, 60 } },
193 
194  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 24, 32, 48, 48, 48, 48, 48, 48 },
195  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 28, 36, 56, 56, 56, 56, 56, 56 },
196  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 32, 48, 60, 60, 60, 60, 60, 60, 60 } },
197 
198  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 20, 32, 40, 48, 48, 48, 48 },
199  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 24, 36, 44, 56, 56, 56, 56 },
200  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 28, 44, 60, 60, 60, 60, 60, 60 } }
201 };
202 
203 
204 /**
205  * LUT to select the coupling start band based on the bit rate, sample rate, and
206  * number of full-bandwidth channels. -1 = coupling off
207  * ac3_coupling_start_tab[channel_mode-2][sample rate code][bit rate code]
208  *
209  * TODO: more testing for optimal parameters.
210  * multi-channel tests at 44.1kHz and 32kHz.
211  */
212 static const int8_t ac3_coupling_start_tab[6][3][19] = {
213 // 32 40 48 56 64 80 96 112 128 160 192 224 256 320 384 448 512 576 640
214 
215  // 2/0
216  { { 0, 0, 0, 0, 0, 0, 0, 1, 1, 7, 8, 11, 12, -1, -1, -1, -1, -1, -1 },
217  { 0, 0, 0, 0, 0, 0, 1, 3, 5, 7, 10, 12, 13, -1, -1, -1, -1, -1, -1 },
218  { 0, 0, 0, 0, 1, 2, 2, 9, 13, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
219 
220  // 3/0
221  { { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
222  { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
223  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
224 
225  // 2/1 - untested
226  { { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
227  { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
228  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
229 
230  // 3/1
231  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
232  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
233  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
234 
235  // 2/2 - untested
236  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
237  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
238  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
239 
240  // 3/2
241  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 6, 8, 11, 12, 12, -1, -1 },
242  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 6, 8, 11, 12, 12, -1, -1 },
243  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
244 };
245 
246 
247 /**
248  * Adjust the frame size to make the average bit rate match the target bit rate.
249  * This is only needed for 11025, 22050, and 44100 sample rates or any E-AC-3.
250  *
251  * @param s AC-3 encoder private context
252  */
254 {
255  while (s->bits_written >= s->bit_rate && s->samples_written >= s->sample_rate) {
256  s->bits_written -= s->bit_rate;
257  s->samples_written -= s->sample_rate;
258  }
259  s->frame_size = s->frame_size_min +
260  2 * (s->bits_written * s->sample_rate < s->samples_written * s->bit_rate);
261  s->bits_written += s->frame_size * 8;
262  s->samples_written += AC3_BLOCK_SIZE * s->num_blocks;
263 }
264 
265 
266 /**
267  * Set the initial coupling strategy parameters prior to coupling analysis.
268  *
269  * @param s AC-3 encoder private context
270  */
272 {
273  int blk, ch;
274  int got_cpl_snr;
275  int num_cpl_blocks;
276 
277  /* set coupling use flags for each block/channel */
278  /* TODO: turn coupling on/off and adjust start band based on bit usage */
279  for (blk = 0; blk < s->num_blocks; blk++) {
280  AC3Block *block = &s->blocks[blk];
281  for (ch = 1; ch <= s->fbw_channels; ch++)
282  block->channel_in_cpl[ch] = s->cpl_on;
283  }
284 
285  /* enable coupling for each block if at least 2 channels have coupling
286  enabled for that block */
287  got_cpl_snr = 0;
288  num_cpl_blocks = 0;
289  for (blk = 0; blk < s->num_blocks; blk++) {
290  AC3Block *block = &s->blocks[blk];
291  block->num_cpl_channels = 0;
292  for (ch = 1; ch <= s->fbw_channels; ch++)
293  block->num_cpl_channels += block->channel_in_cpl[ch];
294  block->cpl_in_use = block->num_cpl_channels > 1;
295  num_cpl_blocks += block->cpl_in_use;
296  if (!block->cpl_in_use) {
297  block->num_cpl_channels = 0;
298  for (ch = 1; ch <= s->fbw_channels; ch++)
299  block->channel_in_cpl[ch] = 0;
300  }
301 
302  block->new_cpl_strategy = !blk;
303  if (blk) {
304  for (ch = 1; ch <= s->fbw_channels; ch++) {
305  if (block->channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) {
306  block->new_cpl_strategy = 1;
307  break;
308  }
309  }
310  }
311  block->new_cpl_leak = block->new_cpl_strategy;
312 
313  if (!blk || (block->cpl_in_use && !got_cpl_snr)) {
314  block->new_snr_offsets = 1;
315  if (block->cpl_in_use)
316  got_cpl_snr = 1;
317  } else {
318  block->new_snr_offsets = 0;
319  }
320  }
321  if (!num_cpl_blocks)
322  s->cpl_on = 0;
323 
324  /* set bandwidth for each channel */
325  for (blk = 0; blk < s->num_blocks; blk++) {
326  AC3Block *block = &s->blocks[blk];
327  for (ch = 1; ch <= s->fbw_channels; ch++) {
328  if (block->channel_in_cpl[ch])
329  block->end_freq[ch] = s->start_freq[CPL_CH];
330  else
331  block->end_freq[ch] = s->bandwidth_code * 3 + 73;
332  }
333  }
334 }
335 
336 
337 /**
338  * Apply stereo rematrixing to coefficients based on rematrixing flags.
339  *
340  * @param s AC-3 encoder private context
341  */
343 {
344  int nb_coefs;
345  int blk, bnd, i;
346  int start, end;
347  uint8_t *flags = NULL;
348 
349  if (!s->rematrixing_enabled)
350  return;
351 
352  for (blk = 0; blk < s->num_blocks; blk++) {
353  AC3Block *block = &s->blocks[blk];
354  if (block->new_rematrixing_strategy)
355  flags = block->rematrixing_flags;
356  nb_coefs = FFMIN(block->end_freq[1], block->end_freq[2]);
357  for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++) {
358  if (flags[bnd]) {
359  start = ff_ac3_rematrix_band_tab[bnd];
360  end = FFMIN(nb_coefs, ff_ac3_rematrix_band_tab[bnd+1]);
361  for (i = start; i < end; i++) {
362  int32_t lt = block->fixed_coef[1][i];
363  int32_t rt = block->fixed_coef[2][i];
364  block->fixed_coef[1][i] = (lt + rt) >> 1;
365  block->fixed_coef[2][i] = (lt - rt) >> 1;
366  }
367  }
368  }
369  }
370 }
371 
372 
373 /*
374  * Initialize exponent tables.
375  */
376 static av_cold void exponent_init(void)
377 {
378  int expstr, i, grpsize;
379 
380  for (expstr = EXP_D15-1; expstr <= EXP_D45-1; expstr++) {
381  grpsize = 3 << expstr;
382  for (i = 12; i < 256; i++) {
383  exponent_group_tab[0][expstr][i] = (i + grpsize - 4) / grpsize;
384  exponent_group_tab[1][expstr][i] = (i ) / grpsize;
385  }
386  }
387  /* LFE */
388  exponent_group_tab[0][0][7] = 2;
389 }
390 
391 
392 /*
393  * Extract exponents from the MDCT coefficients.
394  */
396 {
397  int ch = !s->cpl_on;
398  int chan_size = AC3_MAX_COEFS * s->num_blocks * (s->channels - ch + 1);
399  AC3Block *block = &s->blocks[0];
400 
401  s->ac3dsp.extract_exponents(block->exp[ch], block->fixed_coef[ch], chan_size);
402 }
403 
404 
405 /**
406  * Exponent Difference Threshold.
407  * New exponents are sent if their SAD exceed this number.
408  */
409 #define EXP_DIFF_THRESHOLD 500
410 
411 /**
412  * Table used to select exponent strategy based on exponent reuse block interval.
413  */
414 static const uint8_t exp_strategy_reuse_tab[4][6] = {
419 };
420 
421 /*
422  * Calculate exponent strategies for all channels.
423  * Array arrangement is reversed to simplify the per-channel calculation.
424  */
426 {
427  int ch, blk, blk1;
428 
429  for (ch = !s->cpl_on; ch <= s->fbw_channels; ch++) {
430  uint8_t *exp_strategy = s->exp_strategy[ch];
431  uint8_t *exp = s->blocks[0].exp[ch];
432  int exp_diff;
433 
434  /* estimate if the exponent variation & decide if they should be
435  reused in the next frame */
436  exp_strategy[0] = EXP_NEW;
437  exp += AC3_MAX_COEFS;
438  for (blk = 1; blk < s->num_blocks; blk++, exp += AC3_MAX_COEFS) {
439  if (ch == CPL_CH) {
440  if (!s->blocks[blk-1].cpl_in_use) {
441  exp_strategy[blk] = EXP_NEW;
442  continue;
443  } else if (!s->blocks[blk].cpl_in_use) {
444  exp_strategy[blk] = EXP_REUSE;
445  continue;
446  }
447  } else if (s->blocks[blk].channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) {
448  exp_strategy[blk] = EXP_NEW;
449  continue;
450  }
451  exp_diff = s->mecc.sad[0](NULL, exp, exp - AC3_MAX_COEFS, 16, 16);
452  exp_strategy[blk] = EXP_REUSE;
453  if (ch == CPL_CH && exp_diff > (EXP_DIFF_THRESHOLD * (s->blocks[blk].end_freq[ch] - s->start_freq[ch]) / AC3_MAX_COEFS))
454  exp_strategy[blk] = EXP_NEW;
455  else if (ch > CPL_CH && exp_diff > EXP_DIFF_THRESHOLD)
456  exp_strategy[blk] = EXP_NEW;
457  }
458 
459  /* now select the encoding strategy type : if exponents are often
460  recoded, we use a coarse encoding */
461  blk = 0;
462  while (blk < s->num_blocks) {
463  blk1 = blk + 1;
464  while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE)
465  blk1++;
466  exp_strategy[blk] = exp_strategy_reuse_tab[s->num_blks_code][blk1-blk-1];
467  blk = blk1;
468  }
469  }
470  if (s->lfe_on) {
471  ch = s->lfe_channel;
472  s->exp_strategy[ch][0] = EXP_D15;
473  for (blk = 1; blk < s->num_blocks; blk++)
474  s->exp_strategy[ch][blk] = EXP_REUSE;
475  }
476 
477  /* for E-AC-3, determine frame exponent strategy */
478  if (CONFIG_EAC3_ENCODER && s->eac3)
480 }
481 
482 
483 /**
484  * Update the exponents so that they are the ones the decoder will decode.
485  *
486  * @param[in,out] exp array of exponents for 1 block in 1 channel
487  * @param nb_exps number of exponents in active bandwidth
488  * @param exp_strategy exponent strategy for the block
489  * @param cpl indicates if the block is in the coupling channel
490  */
491 static void encode_exponents_blk_ch(uint8_t *exp, int nb_exps, int exp_strategy,
492  int cpl)
493 {
494  int nb_groups, i, k;
495 
496  nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_exps] * 3;
497 
498  /* for each group, compute the minimum exponent */
499  switch(exp_strategy) {
500  case EXP_D25:
501  for (i = 1, k = 1-cpl; i <= nb_groups; i++) {
502  uint8_t exp_min = exp[k];
503  if (exp[k+1] < exp_min)
504  exp_min = exp[k+1];
505  exp[i-cpl] = exp_min;
506  k += 2;
507  }
508  break;
509  case EXP_D45:
510  for (i = 1, k = 1-cpl; i <= nb_groups; i++) {
511  uint8_t exp_min = exp[k];
512  if (exp[k+1] < exp_min)
513  exp_min = exp[k+1];
514  if (exp[k+2] < exp_min)
515  exp_min = exp[k+2];
516  if (exp[k+3] < exp_min)
517  exp_min = exp[k+3];
518  exp[i-cpl] = exp_min;
519  k += 4;
520  }
521  break;
522  }
523 
524  /* constraint for DC exponent */
525  if (!cpl && exp[0] > 15)
526  exp[0] = 15;
527 
528  /* decrease the delta between each groups to within 2 so that they can be
529  differentially encoded */
530  for (i = 1; i <= nb_groups; i++)
531  exp[i] = FFMIN(exp[i], exp[i-1] + 2);
532  i--;
533  while (--i >= 0)
534  exp[i] = FFMIN(exp[i], exp[i+1] + 2);
535 
536  if (cpl)
537  exp[-1] = exp[0] & ~1;
538 
539  /* now we have the exponent values the decoder will see */
540  switch (exp_strategy) {
541  case EXP_D25:
542  for (i = nb_groups, k = (nb_groups * 2)-cpl; i > 0; i--) {
543  uint8_t exp1 = exp[i-cpl];
544  exp[k--] = exp1;
545  exp[k--] = exp1;
546  }
547  break;
548  case EXP_D45:
549  for (i = nb_groups, k = (nb_groups * 4)-cpl; i > 0; i--) {
550  exp[k] = exp[k-1] = exp[k-2] = exp[k-3] = exp[i-cpl];
551  k -= 4;
552  }
553  break;
554  }
555 }
556 
557 
558 /*
559  * Encode exponents from original extracted form to what the decoder will see.
560  * This copies and groups exponents based on exponent strategy and reduces
561  * deltas between adjacent exponent groups so that they can be differentially
562  * encoded.
563  */
565 {
566  int blk, blk1, ch, cpl;
567  uint8_t *exp, *exp_strategy;
568  int nb_coefs, num_reuse_blocks;
569 
570  for (ch = !s->cpl_on; ch <= s->channels; ch++) {
571  exp = s->blocks[0].exp[ch] + s->start_freq[ch];
572  exp_strategy = s->exp_strategy[ch];
573 
574  cpl = (ch == CPL_CH);
575  blk = 0;
576  while (blk < s->num_blocks) {
577  AC3Block *block = &s->blocks[blk];
578  if (cpl && !block->cpl_in_use) {
579  exp += AC3_MAX_COEFS;
580  blk++;
581  continue;
582  }
583  nb_coefs = block->end_freq[ch] - s->start_freq[ch];
584  blk1 = blk + 1;
585 
586  /* count the number of EXP_REUSE blocks after the current block
587  and set exponent reference block numbers */
588  s->exp_ref_block[ch][blk] = blk;
589  while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE) {
590  s->exp_ref_block[ch][blk1] = blk;
591  blk1++;
592  }
593  num_reuse_blocks = blk1 - blk - 1;
594 
595  /* for the EXP_REUSE case we select the min of the exponents */
596  s->ac3dsp.ac3_exponent_min(exp-s->start_freq[ch], num_reuse_blocks,
597  AC3_MAX_COEFS);
598 
599  encode_exponents_blk_ch(exp, nb_coefs, exp_strategy[blk], cpl);
600 
601  exp += AC3_MAX_COEFS * (num_reuse_blocks + 1);
602  blk = blk1;
603  }
604  }
605 
606  /* reference block numbers have been changed, so reset ref_bap_set */
607  s->ref_bap_set = 0;
608 }
609 
610 
611 /*
612  * Count exponent bits based on bandwidth, coupling, and exponent strategies.
613  */
615 {
616  int blk, ch;
617  int nb_groups, bit_count;
618 
619  bit_count = 0;
620  for (blk = 0; blk < s->num_blocks; blk++) {
621  AC3Block *block = &s->blocks[blk];
622  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
623  int exp_strategy = s->exp_strategy[ch][blk];
624  int cpl = (ch == CPL_CH);
625  int nb_coefs = block->end_freq[ch] - s->start_freq[ch];
626 
627  if (exp_strategy == EXP_REUSE)
628  continue;
629 
630  nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_coefs];
631  bit_count += 4 + (nb_groups * 7);
632  }
633  }
634 
635  return bit_count;
636 }
637 
638 
639 /**
640  * Group exponents.
641  * 3 delta-encoded exponents are in each 7-bit group. The number of groups
642  * varies depending on exponent strategy and bandwidth.
643  *
644  * @param s AC-3 encoder private context
645  */
647 {
648  int blk, ch, i, cpl;
649  int group_size, nb_groups;
650  uint8_t *p;
651  int delta0, delta1, delta2;
652  int exp0, exp1;
653 
654  for (blk = 0; blk < s->num_blocks; blk++) {
655  AC3Block *block = &s->blocks[blk];
656  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
657  int exp_strategy = s->exp_strategy[ch][blk];
658  if (exp_strategy == EXP_REUSE)
659  continue;
660  cpl = (ch == CPL_CH);
661  group_size = exp_strategy + (exp_strategy == EXP_D45);
662  nb_groups = exponent_group_tab[cpl][exp_strategy-1][block->end_freq[ch]-s->start_freq[ch]];
663  p = block->exp[ch] + s->start_freq[ch] - cpl;
664 
665  /* DC exponent */
666  exp1 = *p++;
667  block->grouped_exp[ch][0] = exp1;
668 
669  /* remaining exponents are delta encoded */
670  for (i = 1; i <= nb_groups; i++) {
671  /* merge three delta in one code */
672  exp0 = exp1;
673  exp1 = p[0];
674  p += group_size;
675  delta0 = exp1 - exp0 + 2;
676  av_assert2(delta0 >= 0 && delta0 <= 4);
677 
678  exp0 = exp1;
679  exp1 = p[0];
680  p += group_size;
681  delta1 = exp1 - exp0 + 2;
682  av_assert2(delta1 >= 0 && delta1 <= 4);
683 
684  exp0 = exp1;
685  exp1 = p[0];
686  p += group_size;
687  delta2 = exp1 - exp0 + 2;
688  av_assert2(delta2 >= 0 && delta2 <= 4);
689 
690  block->grouped_exp[ch][i] = ((delta0 * 5 + delta1) * 5) + delta2;
691  }
692  }
693  }
694 }
695 
696 
697 /**
698  * Calculate final exponents from the supplied MDCT coefficients and exponent shift.
699  * Extract exponents from MDCT coefficients, calculate exponent strategies,
700  * and encode final exponents.
701  *
702  * @param s AC-3 encoder private context
703  */
705 {
707 
709 
711 
712  emms_c();
713 }
714 
715 
716 /*
717  * Count frame bits that are based solely on fixed parameters.
718  * This only has to be run once when the encoder is initialized.
719  */
721 {
722  static const uint8_t frame_bits_inc[8] = { 0, 0, 2, 2, 2, 4, 2, 4 };
723  int blk;
724  int frame_bits;
725 
726  /* assumptions:
727  * no dynamic range codes
728  * bit allocation parameters do not change between blocks
729  * no delta bit allocation
730  * no skipped data
731  * no auxiliary data
732  * no E-AC-3 metadata
733  */
734 
735  /* header */
736  frame_bits = 16; /* sync info */
737  if (s->eac3) {
738  /* bitstream info header */
739  frame_bits += 35;
740  frame_bits += 1 + 1;
741  if (s->num_blocks != 0x6)
742  frame_bits++;
743  frame_bits++;
744  /* audio frame header */
745  if (s->num_blocks == 6)
746  frame_bits += 2;
747  frame_bits += 10;
748  /* exponent strategy */
749  if (s->use_frame_exp_strategy)
750  frame_bits += 5 * s->fbw_channels;
751  else
752  frame_bits += s->num_blocks * 2 * s->fbw_channels;
753  if (s->lfe_on)
754  frame_bits += s->num_blocks;
755  /* converter exponent strategy */
756  if (s->num_blks_code != 0x3)
757  frame_bits++;
758  else
759  frame_bits += s->fbw_channels * 5;
760  /* snr offsets */
761  frame_bits += 10;
762  /* block start info */
763  if (s->num_blocks != 1)
764  frame_bits++;
765  } else {
766  frame_bits += 49;
767  frame_bits += frame_bits_inc[s->channel_mode];
768  }
769 
770  /* audio blocks */
771  for (blk = 0; blk < s->num_blocks; blk++) {
772  if (!s->eac3) {
773  /* block switch flags */
774  frame_bits += s->fbw_channels;
775 
776  /* dither flags */
777  frame_bits += s->fbw_channels;
778  }
779 
780  /* dynamic range */
781  frame_bits++;
782 
783  /* spectral extension */
784  if (s->eac3)
785  frame_bits++;
786 
787  if (!s->eac3) {
788  /* exponent strategy */
789  frame_bits += 2 * s->fbw_channels;
790  if (s->lfe_on)
791  frame_bits++;
792 
793  /* bit allocation params */
794  frame_bits++;
795  if (!blk)
796  frame_bits += 2 + 2 + 2 + 2 + 3;
797  }
798 
799  /* converter snr offset */
800  if (s->eac3)
801  frame_bits++;
802 
803  if (!s->eac3) {
804  /* delta bit allocation */
805  frame_bits++;
806 
807  /* skipped data */
808  frame_bits++;
809  }
810  }
811 
812  /* auxiliary data */
813  frame_bits++;
814 
815  /* CRC */
816  frame_bits += 1 + 16;
817 
818  s->frame_bits_fixed = frame_bits;
819 }
820 
821 
822 /*
823  * Initialize bit allocation.
824  * Set default parameter codes and calculate parameter values.
825  */
827 {
828  int ch;
829 
830  /* init default parameters */
831  s->slow_decay_code = 2;
832  s->fast_decay_code = 1;
833  s->slow_gain_code = 1;
834  s->db_per_bit_code = s->eac3 ? 2 : 3;
835  s->floor_code = 7;
836  for (ch = 0; ch <= s->channels; ch++)
837  s->fast_gain_code[ch] = 4;
838 
839  /* initial snr offset */
840  s->coarse_snr_offset = 40;
841 
842  /* compute real values */
843  /* currently none of these values change during encoding, so we can just
844  set them once at initialization */
845  s->bit_alloc.slow_decay = ff_ac3_slow_decay_tab[s->slow_decay_code] >> s->bit_alloc.sr_shift;
846  s->bit_alloc.fast_decay = ff_ac3_fast_decay_tab[s->fast_decay_code] >> s->bit_alloc.sr_shift;
847  s->bit_alloc.slow_gain = ff_ac3_slow_gain_tab[s->slow_gain_code];
848  s->bit_alloc.db_per_bit = ff_ac3_db_per_bit_tab[s->db_per_bit_code];
849  s->bit_alloc.floor = ff_ac3_floor_tab[s->floor_code];
850  s->bit_alloc.cpl_fast_leak = 0;
851  s->bit_alloc.cpl_slow_leak = 0;
852 
854 }
855 
856 
857 /*
858  * Count the bits used to encode the frame, minus exponents and mantissas.
859  * Bits based on fixed parameters have already been counted, so now we just
860  * have to add the bits based on parameters that change during encoding.
861  */
863 {
864  AC3EncOptions *opt = &s->options;
865  int blk, ch;
866  int frame_bits = 0;
867 
868  /* header */
869  if (s->eac3) {
870  if (opt->eac3_mixing_metadata) {
871  if (s->channel_mode > AC3_CHMODE_STEREO)
872  frame_bits += 2;
873  if (s->has_center)
874  frame_bits += 6;
875  if (s->has_surround)
876  frame_bits += 6;
877  frame_bits += s->lfe_on;
878  frame_bits += 1 + 1 + 2;
879  if (s->channel_mode < AC3_CHMODE_STEREO)
880  frame_bits++;
881  frame_bits++;
882  }
883  if (opt->eac3_info_metadata) {
884  frame_bits += 3 + 1 + 1;
885  if (s->channel_mode == AC3_CHMODE_STEREO)
886  frame_bits += 2 + 2;
887  if (s->channel_mode >= AC3_CHMODE_2F2R)
888  frame_bits += 2;
889  frame_bits++;
890  if (opt->audio_production_info)
891  frame_bits += 5 + 2 + 1;
892  frame_bits++;
893  }
894  /* coupling */
895  if (s->channel_mode > AC3_CHMODE_MONO) {
896  frame_bits++;
897  for (blk = 1; blk < s->num_blocks; blk++) {
898  AC3Block *block = &s->blocks[blk];
899  frame_bits++;
900  if (block->new_cpl_strategy)
901  frame_bits++;
902  }
903  }
904  /* coupling exponent strategy */
905  if (s->cpl_on) {
906  if (s->use_frame_exp_strategy) {
907  frame_bits += 5 * s->cpl_on;
908  } else {
909  for (blk = 0; blk < s->num_blocks; blk++)
910  frame_bits += 2 * s->blocks[blk].cpl_in_use;
911  }
912  }
913  } else {
914  if (opt->audio_production_info)
915  frame_bits += 7;
916  if (s->bitstream_id == 6) {
917  if (opt->extended_bsi_1)
918  frame_bits += 14;
919  if (opt->extended_bsi_2)
920  frame_bits += 14;
921  }
922  }
923 
924  /* audio blocks */
925  for (blk = 0; blk < s->num_blocks; blk++) {
926  AC3Block *block = &s->blocks[blk];
927 
928  /* coupling strategy */
929  if (!s->eac3)
930  frame_bits++;
931  if (block->new_cpl_strategy) {
932  if (!s->eac3)
933  frame_bits++;
934  if (block->cpl_in_use) {
935  if (s->eac3)
936  frame_bits++;
937  if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO)
938  frame_bits += s->fbw_channels;
939  if (s->channel_mode == AC3_CHMODE_STEREO)
940  frame_bits++;
941  frame_bits += 4 + 4;
942  if (s->eac3)
943  frame_bits++;
944  else
945  frame_bits += s->num_cpl_subbands - 1;
946  }
947  }
948 
949  /* coupling coordinates */
950  if (block->cpl_in_use) {
951  for (ch = 1; ch <= s->fbw_channels; ch++) {
952  if (block->channel_in_cpl[ch]) {
953  if (!s->eac3 || block->new_cpl_coords[ch] != 2)
954  frame_bits++;
955  if (block->new_cpl_coords[ch]) {
956  frame_bits += 2;
957  frame_bits += (4 + 4) * s->num_cpl_bands;
958  }
959  }
960  }
961  }
962 
963  /* stereo rematrixing */
964  if (s->channel_mode == AC3_CHMODE_STEREO) {
965  if (!s->eac3 || blk > 0)
966  frame_bits++;
967  if (s->blocks[blk].new_rematrixing_strategy)
968  frame_bits += block->num_rematrixing_bands;
969  }
970 
971  /* bandwidth codes & gain range */
972  for (ch = 1; ch <= s->fbw_channels; ch++) {
973  if (s->exp_strategy[ch][blk] != EXP_REUSE) {
974  if (!block->channel_in_cpl[ch])
975  frame_bits += 6;
976  frame_bits += 2;
977  }
978  }
979 
980  /* coupling exponent strategy */
981  if (!s->eac3 && block->cpl_in_use)
982  frame_bits += 2;
983 
984  /* snr offsets and fast gain codes */
985  if (!s->eac3) {
986  frame_bits++;
987  if (block->new_snr_offsets)
988  frame_bits += 6 + (s->channels + block->cpl_in_use) * (4 + 3);
989  }
990 
991  /* coupling leak info */
992  if (block->cpl_in_use) {
993  if (!s->eac3 || block->new_cpl_leak != 2)
994  frame_bits++;
995  if (block->new_cpl_leak)
996  frame_bits += 3 + 3;
997  }
998  }
999 
1000  s->frame_bits = s->frame_bits_fixed + frame_bits;
1001 }
1002 
1003 
1004 /*
1005  * Calculate masking curve based on the final exponents.
1006  * Also calculate the power spectral densities to use in future calculations.
1007  */
1009 {
1010  int blk, ch;
1011 
1012  for (blk = 0; blk < s->num_blocks; blk++) {
1013  AC3Block *block = &s->blocks[blk];
1014  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1015  /* We only need psd and mask for calculating bap.
1016  Since we currently do not calculate bap when exponent
1017  strategy is EXP_REUSE we do not need to calculate psd or mask. */
1018  if (s->exp_strategy[ch][blk] != EXP_REUSE) {
1019  ff_ac3_bit_alloc_calc_psd(block->exp[ch], s->start_freq[ch],
1020  block->end_freq[ch], block->psd[ch],
1021  block->band_psd[ch]);
1022  ff_ac3_bit_alloc_calc_mask(&s->bit_alloc, block->band_psd[ch],
1023  s->start_freq[ch], block->end_freq[ch],
1024  ff_ac3_fast_gain_tab[s->fast_gain_code[ch]],
1025  ch == s->lfe_channel,
1026  DBA_NONE, 0, NULL, NULL, NULL,
1027  block->mask[ch]);
1028  }
1029  }
1030  }
1031 }
1032 
1033 
1034 /*
1035  * Ensure that bap for each block and channel point to the current bap_buffer.
1036  * They may have been switched during the bit allocation search.
1037  */
1039 {
1040  int blk, ch;
1041  uint8_t *ref_bap;
1042 
1043  if (s->ref_bap[0][0] == s->bap_buffer && s->ref_bap_set)
1044  return;
1045 
1046  ref_bap = s->bap_buffer;
1047  for (ch = 0; ch <= s->channels; ch++) {
1048  for (blk = 0; blk < s->num_blocks; blk++)
1049  s->ref_bap[ch][blk] = ref_bap + AC3_MAX_COEFS * s->exp_ref_block[ch][blk];
1050  ref_bap += AC3_MAX_COEFS * s->num_blocks;
1051  }
1052  s->ref_bap_set = 1;
1053 }
1054 
1055 
1056 /**
1057  * Initialize mantissa counts.
1058  * These are set so that they are padded to the next whole group size when bits
1059  * are counted in compute_mantissa_size.
1060  *
1061  * @param[in,out] mant_cnt running counts for each bap value for each block
1062  */
1063 static void count_mantissa_bits_init(uint16_t mant_cnt[AC3_MAX_BLOCKS][16])
1064 {
1065  int blk;
1066 
1067  for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
1068  memset(mant_cnt[blk], 0, sizeof(mant_cnt[blk]));
1069  mant_cnt[blk][1] = mant_cnt[blk][2] = 2;
1070  mant_cnt[blk][4] = 1;
1071  }
1072 }
1073 
1074 
1075 /**
1076  * Update mantissa bit counts for all blocks in 1 channel in a given bandwidth
1077  * range.
1078  *
1079  * @param s AC-3 encoder private context
1080  * @param ch channel index
1081  * @param[in,out] mant_cnt running counts for each bap value for each block
1082  * @param start starting coefficient bin
1083  * @param end ending coefficient bin
1084  */
1086  uint16_t mant_cnt[AC3_MAX_BLOCKS][16],
1087  int start, int end)
1088 {
1089  int blk;
1090 
1091  for (blk = 0; blk < s->num_blocks; blk++) {
1092  AC3Block *block = &s->blocks[blk];
1093  if (ch == CPL_CH && !block->cpl_in_use)
1094  continue;
1095  s->ac3dsp.update_bap_counts(mant_cnt[blk],
1096  s->ref_bap[ch][blk] + start,
1097  FFMIN(end, block->end_freq[ch]) - start);
1098  }
1099 }
1100 
1101 
1102 /*
1103  * Count the number of mantissa bits in the frame based on the bap values.
1104  */
1106 {
1107  int ch, max_end_freq;
1108  LOCAL_ALIGNED_16(uint16_t, mant_cnt, [AC3_MAX_BLOCKS], [16]);
1109 
1110  count_mantissa_bits_init(mant_cnt);
1111 
1112  max_end_freq = s->bandwidth_code * 3 + 73;
1113  for (ch = !s->cpl_enabled; ch <= s->channels; ch++)
1114  count_mantissa_bits_update_ch(s, ch, mant_cnt, s->start_freq[ch],
1115  max_end_freq);
1116 
1117  return s->ac3dsp.compute_mantissa_size(mant_cnt);
1118 }
1119 
1120 
1121 /**
1122  * Run the bit allocation with a given SNR offset.
1123  * This calculates the bit allocation pointers that will be used to determine
1124  * the quantization of each mantissa.
1125  *
1126  * @param s AC-3 encoder private context
1127  * @param snr_offset SNR offset, 0 to 1023
1128  * @return the number of bits needed for mantissas if the given SNR offset is
1129  * is used.
1130  */
1131 static int bit_alloc(AC3EncodeContext *s, int snr_offset)
1132 {
1133  int blk, ch;
1134 
1135  snr_offset = (snr_offset - 240) * 4;
1136 
1137  reset_block_bap(s);
1138  for (blk = 0; blk < s->num_blocks; blk++) {
1139  AC3Block *block = &s->blocks[blk];
1140 
1141  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1142  /* Currently the only bit allocation parameters which vary across
1143  blocks within a frame are the exponent values. We can take
1144  advantage of that by reusing the bit allocation pointers
1145  whenever we reuse exponents. */
1146  if (s->exp_strategy[ch][blk] != EXP_REUSE) {
1147  s->ac3dsp.bit_alloc_calc_bap(block->mask[ch], block->psd[ch],
1148  s->start_freq[ch], block->end_freq[ch],
1149  snr_offset, s->bit_alloc.floor,
1150  ff_ac3_bap_tab, s->ref_bap[ch][blk]);
1151  }
1152  }
1153  }
1154  return count_mantissa_bits(s);
1155 }
1156 
1157 
1158 /*
1159  * Constant bitrate bit allocation search.
1160  * Find the largest SNR offset that will allow data to fit in the frame.
1161  */
1163 {
1164  int ch;
1165  int bits_left;
1166  int snr_offset, snr_incr;
1167 
1168  bits_left = 8 * s->frame_size - (s->frame_bits + s->exponent_bits);
1169  if (bits_left < 0)
1170  return AVERROR(EINVAL);
1171 
1172  snr_offset = s->coarse_snr_offset << 4;
1173 
1174  /* if previous frame SNR offset was 1023, check if current frame can also
1175  use SNR offset of 1023. if so, skip the search. */
1176  if ((snr_offset | s->fine_snr_offset[1]) == 1023) {
1177  if (bit_alloc(s, 1023) <= bits_left)
1178  return 0;
1179  }
1180 
1181  while (snr_offset >= 0 &&
1182  bit_alloc(s, snr_offset) > bits_left) {
1183  snr_offset -= 64;
1184  }
1185  if (snr_offset < 0)
1186  return AVERROR(EINVAL);
1187 
1188  FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1189  for (snr_incr = 64; snr_incr > 0; snr_incr >>= 2) {
1190  while (snr_offset + snr_incr <= 1023 &&
1191  bit_alloc(s, snr_offset + snr_incr) <= bits_left) {
1192  snr_offset += snr_incr;
1193  FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1194  }
1195  }
1196  FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1197  reset_block_bap(s);
1198 
1199  s->coarse_snr_offset = snr_offset >> 4;
1200  for (ch = !s->cpl_on; ch <= s->channels; ch++)
1201  s->fine_snr_offset[ch] = snr_offset & 0xF;
1202 
1203  return 0;
1204 }
1205 
1206 
1207 /*
1208  * Perform bit allocation search.
1209  * Finds the SNR offset value that maximizes quality and fits in the specified
1210  * frame size. Output is the SNR offset and a set of bit allocation pointers
1211  * used to quantize the mantissas.
1212  */
1214 {
1216 
1217  s->exponent_bits = count_exponent_bits(s);
1218 
1220 
1221  return cbr_bit_allocation(s);
1222 }
1223 
1224 
1225 /**
1226  * Symmetric quantization on 'levels' levels.
1227  *
1228  * @param c unquantized coefficient
1229  * @param e exponent
1230  * @param levels number of quantization levels
1231  * @return quantized coefficient
1232  */
1233 static inline int sym_quant(int c, int e, int levels)
1234 {
1235  int v = (((levels * c) >> (24 - e)) + levels) >> 1;
1236  av_assert2(v >= 0 && v < levels);
1237  return v;
1238 }
1239 
1240 
1241 /**
1242  * Asymmetric quantization on 2^qbits levels.
1243  *
1244  * @param c unquantized coefficient
1245  * @param e exponent
1246  * @param qbits number of quantization bits
1247  * @return quantized coefficient
1248  */
1249 static inline int asym_quant(int c, int e, int qbits)
1250 {
1251  int m;
1252 
1253  c = (((c * (1<<e)) >> (24 - qbits)) + 1) >> 1;
1254  m = (1 << (qbits-1));
1255  if (c >= m)
1256  c = m - 1;
1257  av_assert2(c >= -m);
1258  return c;
1259 }
1260 
1261 
1262 /**
1263  * Quantize a set of mantissas for a single channel in a single block.
1264  *
1265  * @param s Mantissa count context
1266  * @param fixed_coef unquantized fixed-point coefficients
1267  * @param exp exponents
1268  * @param bap bit allocation pointer indices
1269  * @param[out] qmant quantized coefficients
1270  * @param start_freq starting coefficient bin
1271  * @param end_freq ending coefficient bin
1272  */
1273 static void quantize_mantissas_blk_ch(AC3Mant *s, int32_t *fixed_coef,
1274  uint8_t *exp, uint8_t *bap,
1275  int16_t *qmant, int start_freq,
1276  int end_freq)
1277 {
1278  int i;
1279 
1280  for (i = start_freq; i < end_freq; i++) {
1281  int c = fixed_coef[i];
1282  int e = exp[i];
1283  int v = bap[i];
1284  if (v)
1285  switch (v) {
1286  case 1:
1287  v = sym_quant(c, e, 3);
1288  switch (s->mant1_cnt) {
1289  case 0:
1290  s->qmant1_ptr = &qmant[i];
1291  v = 9 * v;
1292  s->mant1_cnt = 1;
1293  break;
1294  case 1:
1295  *s->qmant1_ptr += 3 * v;
1296  s->mant1_cnt = 2;
1297  v = 128;
1298  break;
1299  default:
1300  *s->qmant1_ptr += v;
1301  s->mant1_cnt = 0;
1302  v = 128;
1303  break;
1304  }
1305  break;
1306  case 2:
1307  v = sym_quant(c, e, 5);
1308  switch (s->mant2_cnt) {
1309  case 0:
1310  s->qmant2_ptr = &qmant[i];
1311  v = 25 * v;
1312  s->mant2_cnt = 1;
1313  break;
1314  case 1:
1315  *s->qmant2_ptr += 5 * v;
1316  s->mant2_cnt = 2;
1317  v = 128;
1318  break;
1319  default:
1320  *s->qmant2_ptr += v;
1321  s->mant2_cnt = 0;
1322  v = 128;
1323  break;
1324  }
1325  break;
1326  case 3:
1327  v = sym_quant(c, e, 7);
1328  break;
1329  case 4:
1330  v = sym_quant(c, e, 11);
1331  switch (s->mant4_cnt) {
1332  case 0:
1333  s->qmant4_ptr = &qmant[i];
1334  v = 11 * v;
1335  s->mant4_cnt = 1;
1336  break;
1337  default:
1338  *s->qmant4_ptr += v;
1339  s->mant4_cnt = 0;
1340  v = 128;
1341  break;
1342  }
1343  break;
1344  case 5:
1345  v = sym_quant(c, e, 15);
1346  break;
1347  case 14:
1348  v = asym_quant(c, e, 14);
1349  break;
1350  case 15:
1351  v = asym_quant(c, e, 16);
1352  break;
1353  default:
1354  v = asym_quant(c, e, v - 1);
1355  break;
1356  }
1357  qmant[i] = v;
1358  }
1359 }
1360 
1361 
1362 /**
1363  * Quantize mantissas using coefficients, exponents, and bit allocation pointers.
1364  *
1365  * @param s AC-3 encoder private context
1366  */
1368 {
1369  int blk, ch, ch0=0, got_cpl;
1370 
1371  for (blk = 0; blk < s->num_blocks; blk++) {
1372  AC3Block *block = &s->blocks[blk];
1373  AC3Mant m = { 0 };
1374 
1375  got_cpl = !block->cpl_in_use;
1376  for (ch = 1; ch <= s->channels; ch++) {
1377  if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) {
1378  ch0 = ch - 1;
1379  ch = CPL_CH;
1380  got_cpl = 1;
1381  }
1382  quantize_mantissas_blk_ch(&m, block->fixed_coef[ch],
1383  s->blocks[s->exp_ref_block[ch][blk]].exp[ch],
1384  s->ref_bap[ch][blk], block->qmant[ch],
1385  s->start_freq[ch], block->end_freq[ch]);
1386  if (ch == CPL_CH)
1387  ch = ch0;
1388  }
1389  }
1390 }
1391 
1392 
1393 /*
1394  * Write the AC-3 frame header to the output bitstream.
1395  */
1397 {
1398  AC3EncOptions *opt = &s->options;
1399 
1400  put_bits(&s->pb, 16, 0x0b77); /* frame header */
1401  put_bits(&s->pb, 16, 0); /* crc1: will be filled later */
1402  put_bits(&s->pb, 2, s->bit_alloc.sr_code);
1403  put_bits(&s->pb, 6, s->frame_size_code + (s->frame_size - s->frame_size_min) / 2);
1404  put_bits(&s->pb, 5, s->bitstream_id);
1405  put_bits(&s->pb, 3, s->bitstream_mode);
1406  put_bits(&s->pb, 3, s->channel_mode);
1407  if ((s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO)
1408  put_bits(&s->pb, 2, s->center_mix_level);
1409  if (s->channel_mode & 0x04)
1410  put_bits(&s->pb, 2, s->surround_mix_level);
1411  if (s->channel_mode == AC3_CHMODE_STEREO)
1412  put_bits(&s->pb, 2, opt->dolby_surround_mode);
1413  put_bits(&s->pb, 1, s->lfe_on); /* LFE */
1414  put_bits(&s->pb, 5, -opt->dialogue_level);
1415  put_bits(&s->pb, 1, 0); /* no compression control word */
1416  put_bits(&s->pb, 1, 0); /* no lang code */
1417  put_bits(&s->pb, 1, opt->audio_production_info);
1418  if (opt->audio_production_info) {
1419  put_bits(&s->pb, 5, opt->mixing_level - 80);
1420  put_bits(&s->pb, 2, opt->room_type);
1421  }
1422  put_bits(&s->pb, 1, opt->copyright);
1423  put_bits(&s->pb, 1, opt->original);
1424  if (s->bitstream_id == 6) {
1425  /* alternate bit stream syntax */
1426  put_bits(&s->pb, 1, opt->extended_bsi_1);
1427  if (opt->extended_bsi_1) {
1428  put_bits(&s->pb, 2, opt->preferred_stereo_downmix);
1429  put_bits(&s->pb, 3, s->ltrt_center_mix_level);
1430  put_bits(&s->pb, 3, s->ltrt_surround_mix_level);
1431  put_bits(&s->pb, 3, s->loro_center_mix_level);
1432  put_bits(&s->pb, 3, s->loro_surround_mix_level);
1433  }
1434  put_bits(&s->pb, 1, opt->extended_bsi_2);
1435  if (opt->extended_bsi_2) {
1436  put_bits(&s->pb, 2, opt->dolby_surround_ex_mode);
1437  put_bits(&s->pb, 2, opt->dolby_headphone_mode);
1438  put_bits(&s->pb, 1, opt->ad_converter_type);
1439  put_bits(&s->pb, 9, 0); /* xbsi2 and encinfo : reserved */
1440  }
1441  } else {
1442  put_bits(&s->pb, 1, 0); /* no time code 1 */
1443  put_bits(&s->pb, 1, 0); /* no time code 2 */
1444  }
1445  put_bits(&s->pb, 1, 0); /* no additional bit stream info */
1446 }
1447 
1448 
1449 /*
1450  * Write one audio block to the output bitstream.
1451  */
1453 {
1454  int ch, i, baie, bnd, got_cpl, av_uninit(ch0);
1455  AC3Block *block = &s->blocks[blk];
1456 
1457  /* block switching */
1458  if (!s->eac3) {
1459  for (ch = 0; ch < s->fbw_channels; ch++)
1460  put_bits(&s->pb, 1, 0);
1461  }
1462 
1463  /* dither flags */
1464  if (!s->eac3) {
1465  for (ch = 0; ch < s->fbw_channels; ch++)
1466  put_bits(&s->pb, 1, 1);
1467  }
1468 
1469  /* dynamic range codes */
1470  put_bits(&s->pb, 1, 0);
1471 
1472  /* spectral extension */
1473  if (s->eac3)
1474  put_bits(&s->pb, 1, 0);
1475 
1476  /* channel coupling */
1477  if (!s->eac3)
1478  put_bits(&s->pb, 1, block->new_cpl_strategy);
1479  if (block->new_cpl_strategy) {
1480  if (!s->eac3)
1481  put_bits(&s->pb, 1, block->cpl_in_use);
1482  if (block->cpl_in_use) {
1483  int start_sub, end_sub;
1484  if (s->eac3)
1485  put_bits(&s->pb, 1, 0); /* enhanced coupling */
1486  if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO) {
1487  for (ch = 1; ch <= s->fbw_channels; ch++)
1488  put_bits(&s->pb, 1, block->channel_in_cpl[ch]);
1489  }
1490  if (s->channel_mode == AC3_CHMODE_STEREO)
1491  put_bits(&s->pb, 1, 0); /* phase flags in use */
1492  start_sub = (s->start_freq[CPL_CH] - 37) / 12;
1493  end_sub = (s->cpl_end_freq - 37) / 12;
1494  put_bits(&s->pb, 4, start_sub);
1495  put_bits(&s->pb, 4, end_sub - 3);
1496  /* coupling band structure */
1497  if (s->eac3) {
1498  put_bits(&s->pb, 1, 0); /* use default */
1499  } else {
1500  for (bnd = start_sub+1; bnd < end_sub; bnd++)
1502  }
1503  }
1504  }
1505 
1506  /* coupling coordinates */
1507  if (block->cpl_in_use) {
1508  for (ch = 1; ch <= s->fbw_channels; ch++) {
1509  if (block->channel_in_cpl[ch]) {
1510  if (!s->eac3 || block->new_cpl_coords[ch] != 2)
1511  put_bits(&s->pb, 1, block->new_cpl_coords[ch]);
1512  if (block->new_cpl_coords[ch]) {
1513  put_bits(&s->pb, 2, block->cpl_master_exp[ch]);
1514  for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
1515  put_bits(&s->pb, 4, block->cpl_coord_exp [ch][bnd]);
1516  put_bits(&s->pb, 4, block->cpl_coord_mant[ch][bnd]);
1517  }
1518  }
1519  }
1520  }
1521  }
1522 
1523  /* stereo rematrixing */
1524  if (s->channel_mode == AC3_CHMODE_STEREO) {
1525  if (!s->eac3 || blk > 0)
1526  put_bits(&s->pb, 1, block->new_rematrixing_strategy);
1527  if (block->new_rematrixing_strategy) {
1528  /* rematrixing flags */
1529  for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++)
1530  put_bits(&s->pb, 1, block->rematrixing_flags[bnd]);
1531  }
1532  }
1533 
1534  /* exponent strategy */
1535  if (!s->eac3) {
1536  for (ch = !block->cpl_in_use; ch <= s->fbw_channels; ch++)
1537  put_bits(&s->pb, 2, s->exp_strategy[ch][blk]);
1538  if (s->lfe_on)
1539  put_bits(&s->pb, 1, s->exp_strategy[s->lfe_channel][blk]);
1540  }
1541 
1542  /* bandwidth */
1543  for (ch = 1; ch <= s->fbw_channels; ch++) {
1544  if (s->exp_strategy[ch][blk] != EXP_REUSE && !block->channel_in_cpl[ch])
1545  put_bits(&s->pb, 6, s->bandwidth_code);
1546  }
1547 
1548  /* exponents */
1549  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1550  int nb_groups;
1551  int cpl = (ch == CPL_CH);
1552 
1553  if (s->exp_strategy[ch][blk] == EXP_REUSE)
1554  continue;
1555 
1556  /* DC exponent */
1557  put_bits(&s->pb, 4, block->grouped_exp[ch][0] >> cpl);
1558 
1559  /* exponent groups */
1560  nb_groups = exponent_group_tab[cpl][s->exp_strategy[ch][blk]-1][block->end_freq[ch]-s->start_freq[ch]];
1561  for (i = 1; i <= nb_groups; i++)
1562  put_bits(&s->pb, 7, block->grouped_exp[ch][i]);
1563 
1564  /* gain range info */
1565  if (ch != s->lfe_channel && !cpl)
1566  put_bits(&s->pb, 2, 0);
1567  }
1568 
1569  /* bit allocation info */
1570  if (!s->eac3) {
1571  baie = (blk == 0);
1572  put_bits(&s->pb, 1, baie);
1573  if (baie) {
1574  put_bits(&s->pb, 2, s->slow_decay_code);
1575  put_bits(&s->pb, 2, s->fast_decay_code);
1576  put_bits(&s->pb, 2, s->slow_gain_code);
1577  put_bits(&s->pb, 2, s->db_per_bit_code);
1578  put_bits(&s->pb, 3, s->floor_code);
1579  }
1580  }
1581 
1582  /* snr offset */
1583  if (!s->eac3) {
1584  put_bits(&s->pb, 1, block->new_snr_offsets);
1585  if (block->new_snr_offsets) {
1586  put_bits(&s->pb, 6, s->coarse_snr_offset);
1587  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1588  put_bits(&s->pb, 4, s->fine_snr_offset[ch]);
1589  put_bits(&s->pb, 3, s->fast_gain_code[ch]);
1590  }
1591  }
1592  } else {
1593  put_bits(&s->pb, 1, 0); /* no converter snr offset */
1594  }
1595 
1596  /* coupling leak */
1597  if (block->cpl_in_use) {
1598  if (!s->eac3 || block->new_cpl_leak != 2)
1599  put_bits(&s->pb, 1, block->new_cpl_leak);
1600  if (block->new_cpl_leak) {
1601  put_bits(&s->pb, 3, s->bit_alloc.cpl_fast_leak);
1602  put_bits(&s->pb, 3, s->bit_alloc.cpl_slow_leak);
1603  }
1604  }
1605 
1606  if (!s->eac3) {
1607  put_bits(&s->pb, 1, 0); /* no delta bit allocation */
1608  put_bits(&s->pb, 1, 0); /* no data to skip */
1609  }
1610 
1611  /* mantissas */
1612  got_cpl = !block->cpl_in_use;
1613  for (ch = 1; ch <= s->channels; ch++) {
1614  int b, q;
1615 
1616  if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) {
1617  ch0 = ch - 1;
1618  ch = CPL_CH;
1619  got_cpl = 1;
1620  }
1621  for (i = s->start_freq[ch]; i < block->end_freq[ch]; i++) {
1622  q = block->qmant[ch][i];
1623  b = s->ref_bap[ch][blk][i];
1624  switch (b) {
1625  case 0: break;
1626  case 1: if (q != 128) put_bits (&s->pb, 5, q); break;
1627  case 2: if (q != 128) put_bits (&s->pb, 7, q); break;
1628  case 3: put_sbits(&s->pb, 3, q); break;
1629  case 4: if (q != 128) put_bits (&s->pb, 7, q); break;
1630  case 14: put_sbits(&s->pb, 14, q); break;
1631  case 15: put_sbits(&s->pb, 16, q); break;
1632  default: put_sbits(&s->pb, b-1, q); break;
1633  }
1634  }
1635  if (ch == CPL_CH)
1636  ch = ch0;
1637  }
1638 }
1639 
1640 
1641 /** CRC-16 Polynomial */
1642 #define CRC16_POLY ((1 << 0) | (1 << 2) | (1 << 15) | (1 << 16))
1643 
1644 
1645 static unsigned int mul_poly(unsigned int a, unsigned int b, unsigned int poly)
1646 {
1647  unsigned int c;
1648 
1649  c = 0;
1650  while (a) {
1651  if (a & 1)
1652  c ^= b;
1653  a = a >> 1;
1654  b = b << 1;
1655  if (b & (1 << 16))
1656  b ^= poly;
1657  }
1658  return c;
1659 }
1660 
1661 
1662 static unsigned int pow_poly(unsigned int a, unsigned int n, unsigned int poly)
1663 {
1664  unsigned int r;
1665  r = 1;
1666  while (n) {
1667  if (n & 1)
1668  r = mul_poly(r, a, poly);
1669  a = mul_poly(a, a, poly);
1670  n >>= 1;
1671  }
1672  return r;
1673 }
1674 
1675 
1676 /*
1677  * Fill the end of the frame with 0's and compute the two CRCs.
1678  */
1680 {
1681  const AVCRC *crc_ctx = av_crc_get_table(AV_CRC_16_ANSI);
1682  int frame_size_58, pad_bytes, crc1, crc2_partial, crc2, crc_inv;
1683  uint8_t *frame;
1684 
1685  frame_size_58 = ((s->frame_size >> 2) + (s->frame_size >> 4)) << 1;
1686 
1687  /* pad the remainder of the frame with zeros */
1688  av_assert2(s->frame_size * 8 - put_bits_count(&s->pb) >= 18);
1689  flush_put_bits(&s->pb);
1690  frame = s->pb.buf;
1691  pad_bytes = s->frame_size - (put_bits_ptr(&s->pb) - frame) - 2;
1692  av_assert2(pad_bytes >= 0);
1693  if (pad_bytes > 0)
1694  memset(put_bits_ptr(&s->pb), 0, pad_bytes);
1695 
1696  if (s->eac3) {
1697  /* compute crc2 */
1698  crc2_partial = av_crc(crc_ctx, 0, frame + 2, s->frame_size - 5);
1699  } else {
1700  /* compute crc1 */
1701  /* this is not so easy because it is at the beginning of the data... */
1702  crc1 = av_bswap16(av_crc(crc_ctx, 0, frame + 4, frame_size_58 - 4));
1703  crc_inv = s->crc_inv[s->frame_size > s->frame_size_min];
1704  crc1 = mul_poly(crc_inv, crc1, CRC16_POLY);
1705  AV_WB16(frame + 2, crc1);
1706 
1707  /* compute crc2 */
1708  crc2_partial = av_crc(crc_ctx, 0, frame + frame_size_58,
1709  s->frame_size - frame_size_58 - 3);
1710  }
1711  crc2 = av_crc(crc_ctx, crc2_partial, frame + s->frame_size - 3, 1);
1712  /* ensure crc2 does not match sync word by flipping crcrsv bit if needed */
1713  if (crc2 == 0x770B) {
1714  frame[s->frame_size - 3] ^= 0x1;
1715  crc2 = av_crc(crc_ctx, crc2_partial, frame + s->frame_size - 3, 1);
1716  }
1717  crc2 = av_bswap16(crc2);
1718  AV_WB16(frame + s->frame_size - 2, crc2);
1719 }
1720 
1721 
1722 /**
1723  * Write the frame to the output bitstream.
1724  *
1725  * @param s AC-3 encoder private context
1726  * @param frame output data buffer
1727  */
1728 static void ac3_output_frame(AC3EncodeContext *s, unsigned char *frame)
1729 {
1730  int blk;
1731 
1732  init_put_bits(&s->pb, frame, s->frame_size);
1733 
1734  s->output_frame_header(s);
1735 
1736  for (blk = 0; blk < s->num_blocks; blk++)
1738 
1740 }
1741 
1743  const AVFrame *frame, int *got_packet_ptr)
1744 {
1745  AC3EncodeContext *const s = avctx->priv_data;
1746  int ret;
1747 
1749 
1751 
1753  if (ret) {
1754  av_log(avctx, AV_LOG_ERROR, "Bit allocation failed. Try increasing the bitrate.\n");
1755  return ret;
1756  }
1757 
1759 
1761 
1762  if ((ret = ff_alloc_packet2(avctx, avpkt, s->frame_size, 0)) < 0)
1763  return ret;
1764  ac3_output_frame(s, avpkt->data);
1765 
1766  if (frame->pts != AV_NOPTS_VALUE)
1767  avpkt->pts = frame->pts - ff_samples_to_time_base(avctx, avctx->initial_padding);
1768 
1769  *got_packet_ptr = 1;
1770  return 0;
1771 }
1772 
1774 {
1775 #ifdef DEBUG
1776  AVCodecContext *avctx = s->avctx;
1777  AC3EncOptions *opt = &s->options;
1778  char strbuf[32];
1779 
1780  switch (s->bitstream_id) {
1781  case 6: av_strlcpy(strbuf, "AC-3 (alt syntax)", 32); break;
1782  case 8: av_strlcpy(strbuf, "AC-3 (standard)", 32); break;
1783  case 9: av_strlcpy(strbuf, "AC-3 (dnet half-rate)", 32); break;
1784  case 10: av_strlcpy(strbuf, "AC-3 (dnet quater-rate)", 32); break;
1785  case 16: av_strlcpy(strbuf, "E-AC-3 (enhanced)", 32); break;
1786  default: snprintf(strbuf, 32, "ERROR");
1787  }
1788  ff_dlog(avctx, "bitstream_id: %s (%d)\n", strbuf, s->bitstream_id);
1789  ff_dlog(avctx, "sample_fmt: %s\n", av_get_sample_fmt_name(avctx->sample_fmt));
1790  av_get_channel_layout_string(strbuf, 32, s->channels, avctx->channel_layout);
1791  ff_dlog(avctx, "channel_layout: %s\n", strbuf);
1792  ff_dlog(avctx, "sample_rate: %d\n", s->sample_rate);
1793  ff_dlog(avctx, "bit_rate: %d\n", s->bit_rate);
1794  ff_dlog(avctx, "blocks/frame: %d (code=%d)\n", s->num_blocks, s->num_blks_code);
1795  if (s->cutoff)
1796  ff_dlog(avctx, "cutoff: %d\n", s->cutoff);
1797 
1798  ff_dlog(avctx, "per_frame_metadata: %s\n",
1799  opt->allow_per_frame_metadata?"on":"off");
1800  if (s->has_center)
1801  ff_dlog(avctx, "center_mixlev: %0.3f (%d)\n", opt->center_mix_level,
1802  s->center_mix_level);
1803  else
1804  ff_dlog(avctx, "center_mixlev: {not written}\n");
1805  if (s->has_surround)
1806  ff_dlog(avctx, "surround_mixlev: %0.3f (%d)\n", opt->surround_mix_level,
1807  s->surround_mix_level);
1808  else
1809  ff_dlog(avctx, "surround_mixlev: {not written}\n");
1810  if (opt->audio_production_info) {
1811  ff_dlog(avctx, "mixing_level: %ddB\n", opt->mixing_level);
1812  switch (opt->room_type) {
1813  case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1814  case AC3ENC_OPT_LARGE_ROOM: av_strlcpy(strbuf, "large", 32); break;
1815  case AC3ENC_OPT_SMALL_ROOM: av_strlcpy(strbuf, "small", 32); break;
1816  default: snprintf(strbuf, 32, "ERROR (%d)", opt->room_type);
1817  }
1818  ff_dlog(avctx, "room_type: %s\n", strbuf);
1819  } else {
1820  ff_dlog(avctx, "mixing_level: {not written}\n");
1821  ff_dlog(avctx, "room_type: {not written}\n");
1822  }
1823  ff_dlog(avctx, "copyright: %s\n", opt->copyright?"on":"off");
1824  ff_dlog(avctx, "dialnorm: %ddB\n", opt->dialogue_level);
1825  if (s->channel_mode == AC3_CHMODE_STEREO) {
1826  switch (opt->dolby_surround_mode) {
1827  case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1828  case AC3ENC_OPT_MODE_ON: av_strlcpy(strbuf, "on", 32); break;
1829  case AC3ENC_OPT_MODE_OFF: av_strlcpy(strbuf, "off", 32); break;
1830  default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_surround_mode);
1831  }
1832  ff_dlog(avctx, "dsur_mode: %s\n", strbuf);
1833  } else {
1834  ff_dlog(avctx, "dsur_mode: {not written}\n");
1835  }
1836  ff_dlog(avctx, "original: %s\n", opt->original?"on":"off");
1837 
1838  if (s->bitstream_id == 6) {
1839  if (opt->extended_bsi_1) {
1840  switch (opt->preferred_stereo_downmix) {
1841  case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1842  case AC3ENC_OPT_DOWNMIX_LTRT: av_strlcpy(strbuf, "ltrt", 32); break;
1843  case AC3ENC_OPT_DOWNMIX_LORO: av_strlcpy(strbuf, "loro", 32); break;
1844  default: snprintf(strbuf, 32, "ERROR (%d)", opt->preferred_stereo_downmix);
1845  }
1846  ff_dlog(avctx, "dmix_mode: %s\n", strbuf);
1847  ff_dlog(avctx, "ltrt_cmixlev: %0.3f (%d)\n",
1848  opt->ltrt_center_mix_level, s->ltrt_center_mix_level);
1849  ff_dlog(avctx, "ltrt_surmixlev: %0.3f (%d)\n",
1850  opt->ltrt_surround_mix_level, s->ltrt_surround_mix_level);
1851  ff_dlog(avctx, "loro_cmixlev: %0.3f (%d)\n",
1852  opt->loro_center_mix_level, s->loro_center_mix_level);
1853  ff_dlog(avctx, "loro_surmixlev: %0.3f (%d)\n",
1854  opt->loro_surround_mix_level, s->loro_surround_mix_level);
1855  } else {
1856  ff_dlog(avctx, "extended bitstream info 1: {not written}\n");
1857  }
1858  if (opt->extended_bsi_2) {
1859  switch (opt->dolby_surround_ex_mode) {
1860  case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1861  case AC3ENC_OPT_MODE_ON: av_strlcpy(strbuf, "on", 32); break;
1862  case AC3ENC_OPT_MODE_OFF: av_strlcpy(strbuf, "off", 32); break;
1863  default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_surround_ex_mode);
1864  }
1865  ff_dlog(avctx, "dsurex_mode: %s\n", strbuf);
1866  switch (opt->dolby_headphone_mode) {
1867  case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1868  case AC3ENC_OPT_MODE_ON: av_strlcpy(strbuf, "on", 32); break;
1869  case AC3ENC_OPT_MODE_OFF: av_strlcpy(strbuf, "off", 32); break;
1870  default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_headphone_mode);
1871  }
1872  ff_dlog(avctx, "dheadphone_mode: %s\n", strbuf);
1873 
1874  switch (opt->ad_converter_type) {
1875  case AC3ENC_OPT_ADCONV_STANDARD: av_strlcpy(strbuf, "standard", 32); break;
1876  case AC3ENC_OPT_ADCONV_HDCD: av_strlcpy(strbuf, "hdcd", 32); break;
1877  default: snprintf(strbuf, 32, "ERROR (%d)", opt->ad_converter_type);
1878  }
1879  ff_dlog(avctx, "ad_conv_type: %s\n", strbuf);
1880  } else {
1881  ff_dlog(avctx, "extended bitstream info 2: {not written}\n");
1882  }
1883  }
1884 #endif
1885 }
1886 
1887 
1888 #define FLT_OPTION_THRESHOLD 0.01
1889 
1890 static int validate_float_option(float v, const float *v_list, int v_list_size)
1891 {
1892  int i;
1893 
1894  for (i = 0; i < v_list_size; i++) {
1895  if (v < (v_list[i] + FLT_OPTION_THRESHOLD) &&
1896  v > (v_list[i] - FLT_OPTION_THRESHOLD))
1897  break;
1898  }
1899  if (i == v_list_size)
1900  return AVERROR(EINVAL);
1901 
1902  return i;
1903 }
1904 
1905 
1906 static void validate_mix_level(void *log_ctx, const char *opt_name,
1907  float *opt_param, const float *list,
1908  int list_size, int default_value, int min_value,
1909  int *ctx_param)
1910 {
1911  int mixlev = validate_float_option(*opt_param, list, list_size);
1912  if (mixlev < min_value) {
1913  mixlev = default_value;
1914  if (*opt_param >= 0.0) {
1915  av_log(log_ctx, AV_LOG_WARNING, "requested %s is not valid. using "
1916  "default value: %0.3f\n", opt_name, list[mixlev]);
1917  }
1918  }
1919  *opt_param = list[mixlev];
1920  *ctx_param = mixlev;
1921 }
1922 
1923 
1924 /**
1925  * Validate metadata options as set by AVOption system.
1926  * These values can optionally be changed per-frame.
1927  *
1928  * @param s AC-3 encoder private context
1929  */
1931 {
1932  AVCodecContext *avctx = s->avctx;
1933  AC3EncOptions *opt = &s->options;
1934 
1935  opt->audio_production_info = 0;
1936  opt->extended_bsi_1 = 0;
1937  opt->extended_bsi_2 = 0;
1938  opt->eac3_mixing_metadata = 0;
1939  opt->eac3_info_metadata = 0;
1940 
1941  /* determine mixing metadata / xbsi1 use */
1942  if (s->channel_mode > AC3_CHMODE_STEREO && opt->preferred_stereo_downmix != AC3ENC_OPT_NONE) {
1943  opt->extended_bsi_1 = 1;
1944  opt->eac3_mixing_metadata = 1;
1945  }
1946  if (s->has_center &&
1947  (opt->ltrt_center_mix_level >= 0 || opt->loro_center_mix_level >= 0)) {
1948  opt->extended_bsi_1 = 1;
1949  opt->eac3_mixing_metadata = 1;
1950  }
1951  if (s->has_surround &&
1952  (opt->ltrt_surround_mix_level >= 0 || opt->loro_surround_mix_level >= 0)) {
1953  opt->extended_bsi_1 = 1;
1954  opt->eac3_mixing_metadata = 1;
1955  }
1956 
1957  if (s->eac3) {
1958  /* determine info metadata use */
1960  opt->eac3_info_metadata = 1;
1961  if (opt->copyright != AC3ENC_OPT_NONE || opt->original != AC3ENC_OPT_NONE)
1962  opt->eac3_info_metadata = 1;
1963  if (s->channel_mode == AC3_CHMODE_STEREO &&
1965  opt->eac3_info_metadata = 1;
1966  if (s->channel_mode >= AC3_CHMODE_2F2R && opt->dolby_surround_ex_mode != AC3ENC_OPT_NONE)
1967  opt->eac3_info_metadata = 1;
1968  if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE ||
1970  opt->audio_production_info = 1;
1971  opt->eac3_info_metadata = 1;
1972  }
1973  } else {
1974  /* determine audio production info use */
1975  if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE)
1976  opt->audio_production_info = 1;
1977 
1978  /* determine xbsi2 use */
1979  if (s->channel_mode >= AC3_CHMODE_2F2R && opt->dolby_surround_ex_mode != AC3ENC_OPT_NONE)
1980  opt->extended_bsi_2 = 1;
1981  if (s->channel_mode == AC3_CHMODE_STEREO && opt->dolby_headphone_mode != AC3ENC_OPT_NONE)
1982  opt->extended_bsi_2 = 1;
1983  if (opt->ad_converter_type != AC3ENC_OPT_NONE)
1984  opt->extended_bsi_2 = 1;
1985  }
1986 
1987  /* validate AC-3 mixing levels */
1988  if (!s->eac3) {
1989  if (s->has_center) {
1990  validate_mix_level(avctx, "center_mix_level", &opt->center_mix_level,
1992  &s->center_mix_level);
1993  }
1994  if (s->has_surround) {
1995  validate_mix_level(avctx, "surround_mix_level", &opt->surround_mix_level,
1997  &s->surround_mix_level);
1998  }
1999  }
2000 
2001  /* validate extended bsi 1 / mixing metadata */
2002  if (opt->extended_bsi_1 || opt->eac3_mixing_metadata) {
2003  /* default preferred stereo downmix */
2006  if (!s->eac3 || s->has_center) {
2007  /* validate Lt/Rt center mix level */
2008  validate_mix_level(avctx, "ltrt_center_mix_level",
2010  EXTMIXLEV_NUM_OPTIONS, 5, 0,
2011  &s->ltrt_center_mix_level);
2012  /* validate Lo/Ro center mix level */
2013  validate_mix_level(avctx, "loro_center_mix_level",
2015  EXTMIXLEV_NUM_OPTIONS, 5, 0,
2016  &s->loro_center_mix_level);
2017  }
2018  if (!s->eac3 || s->has_surround) {
2019  /* validate Lt/Rt surround mix level */
2020  validate_mix_level(avctx, "ltrt_surround_mix_level",
2022  EXTMIXLEV_NUM_OPTIONS, 6, 3,
2023  &s->ltrt_surround_mix_level);
2024  /* validate Lo/Ro surround mix level */
2025  validate_mix_level(avctx, "loro_surround_mix_level",
2027  EXTMIXLEV_NUM_OPTIONS, 6, 3,
2028  &s->loro_surround_mix_level);
2029  }
2030  }
2031 
2032  /* validate audio service type / channels combination */
2034  avctx->channels == 1) ||
2038  && avctx->channels > 1)) {
2039  av_log(avctx, AV_LOG_ERROR, "invalid audio service type for the "
2040  "specified number of channels\n");
2041  return AVERROR(EINVAL);
2042  }
2043 
2044  /* validate extended bsi 2 / info metadata */
2045  if (opt->extended_bsi_2 || opt->eac3_info_metadata) {
2046  /* default dolby headphone mode */
2049  /* default dolby surround ex mode */
2052  /* default A/D converter type */
2053  if (opt->ad_converter_type == AC3ENC_OPT_NONE)
2055  }
2056 
2057  /* copyright & original defaults */
2058  if (!s->eac3 || opt->eac3_info_metadata) {
2059  /* default copyright */
2060  if (opt->copyright == AC3ENC_OPT_NONE)
2061  opt->copyright = AC3ENC_OPT_OFF;
2062  /* default original */
2063  if (opt->original == AC3ENC_OPT_NONE)
2064  opt->original = AC3ENC_OPT_ON;
2065  }
2066 
2067  /* dolby surround mode default */
2068  if (!s->eac3 || opt->eac3_info_metadata) {
2071  }
2072 
2073  /* validate audio production info */
2074  if (opt->audio_production_info) {
2075  if (opt->mixing_level == AC3ENC_OPT_NONE) {
2076  av_log(avctx, AV_LOG_ERROR, "mixing_level must be set if "
2077  "room_type is set\n");
2078  return AVERROR(EINVAL);
2079  }
2080  if (opt->mixing_level < 80) {
2081  av_log(avctx, AV_LOG_ERROR, "invalid mixing level. must be between "
2082  "80dB and 111dB\n");
2083  return AVERROR(EINVAL);
2084  }
2085  /* default room type */
2086  if (opt->room_type == AC3ENC_OPT_NONE)
2088  }
2089 
2090  /* set bitstream id for alternate bitstream syntax */
2091  if (!s->eac3 && (opt->extended_bsi_1 || opt->extended_bsi_2)) {
2092  if (s->bitstream_id > 8 && s->bitstream_id < 11) {
2093  if (!s->warned_alternate_bitstream) {
2094  av_log(avctx, AV_LOG_WARNING, "alternate bitstream syntax is "
2095  "not compatible with reduced samplerates. writing of "
2096  "extended bitstream information will be disabled.\n");
2097  s->warned_alternate_bitstream = 1;
2098  }
2099  } else {
2100  s->bitstream_id = 6;
2101  }
2102  }
2103 
2104  return 0;
2105 }
2106 
2107 
2108 /**
2109  * Finalize encoding and free any memory allocated by the encoder.
2110  *
2111  * @param avctx Codec context
2112  */
2114 {
2115  int blk, ch;
2116  AC3EncodeContext *s = avctx->priv_data;
2117 
2118  av_freep(&s->mdct_window);
2119  av_freep(&s->windowed_samples);
2120  if (s->planar_samples)
2121  for (ch = 0; ch < s->channels; ch++)
2122  av_freep(&s->planar_samples[ch]);
2123  av_freep(&s->planar_samples);
2124  av_freep(&s->bap_buffer);
2125  av_freep(&s->bap1_buffer);
2126  av_freep(&s->mdct_coef_buffer);
2127  av_freep(&s->fixed_coef_buffer);
2128  av_freep(&s->exp_buffer);
2129  av_freep(&s->grouped_exp_buffer);
2130  av_freep(&s->psd_buffer);
2131  av_freep(&s->band_psd_buffer);
2132  av_freep(&s->mask_buffer);
2133  av_freep(&s->qmant_buffer);
2134  av_freep(&s->cpl_coord_exp_buffer);
2135  av_freep(&s->cpl_coord_mant_buffer);
2136  av_freep(&s->fdsp);
2137  for (blk = 0; blk < s->num_blocks; blk++) {
2138  AC3Block *block = &s->blocks[blk];
2139  av_freep(&block->mdct_coef);
2140  av_freep(&block->fixed_coef);
2141  av_freep(&block->exp);
2142  av_freep(&block->grouped_exp);
2143  av_freep(&block->psd);
2144  av_freep(&block->band_psd);
2145  av_freep(&block->mask);
2146  av_freep(&block->qmant);
2147  av_freep(&block->cpl_coord_exp);
2148  av_freep(&block->cpl_coord_mant);
2149  }
2150 
2151  s->mdct_end(s);
2152 
2153  return 0;
2154 }
2155 
2156 
2157 /*
2158  * Set channel information during initialization.
2159  */
2161  uint64_t *channel_layout)
2162 {
2163  int ch_layout;
2164 
2166  return AVERROR(EINVAL);
2167  if (*channel_layout > 0x7FF)
2168  return AVERROR(EINVAL);
2169  ch_layout = *channel_layout;
2170  if (!ch_layout)
2172 
2173  s->lfe_on = !!(ch_layout & AV_CH_LOW_FREQUENCY);
2174  s->channels = channels;
2175  s->fbw_channels = channels - s->lfe_on;
2176  s->lfe_channel = s->lfe_on ? s->fbw_channels + 1 : -1;
2177  if (s->lfe_on)
2178  ch_layout -= AV_CH_LOW_FREQUENCY;
2179 
2180  switch (ch_layout) {
2181  case AV_CH_LAYOUT_MONO: s->channel_mode = AC3_CHMODE_MONO; break;
2182  case AV_CH_LAYOUT_STEREO: s->channel_mode = AC3_CHMODE_STEREO; break;
2183  case AV_CH_LAYOUT_SURROUND: s->channel_mode = AC3_CHMODE_3F; break;
2184  case AV_CH_LAYOUT_2_1: s->channel_mode = AC3_CHMODE_2F1R; break;
2185  case AV_CH_LAYOUT_4POINT0: s->channel_mode = AC3_CHMODE_3F1R; break;
2186  case AV_CH_LAYOUT_QUAD:
2187  case AV_CH_LAYOUT_2_2: s->channel_mode = AC3_CHMODE_2F2R; break;
2188  case AV_CH_LAYOUT_5POINT0:
2189  case AV_CH_LAYOUT_5POINT0_BACK: s->channel_mode = AC3_CHMODE_3F2R; break;
2190  default:
2191  return AVERROR(EINVAL);
2192  }
2193  s->has_center = (s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO;
2194  s->has_surround = s->channel_mode & 0x04;
2195 
2196  s->channel_map = ac3_enc_channel_map[s->channel_mode][s->lfe_on];
2197  *channel_layout = ch_layout;
2198  if (s->lfe_on)
2199  *channel_layout |= AV_CH_LOW_FREQUENCY;
2200 
2201  return 0;
2202 }
2203 
2204 
2206 {
2207  AVCodecContext *avctx = s->avctx;
2208  int i, ret, max_sr;
2209 
2210  /* validate channel layout */
2211  if (!avctx->channel_layout) {
2212  av_log(avctx, AV_LOG_WARNING, "No channel layout specified. The "
2213  "encoder will guess the layout, but it "
2214  "might be incorrect.\n");
2215  }
2216  ret = set_channel_info(s, avctx->channels, &avctx->channel_layout);
2217  if (ret) {
2218  av_log(avctx, AV_LOG_ERROR, "invalid channel layout\n");
2219  return ret;
2220  }
2221 
2222  /* validate sample rate */
2223  /* note: max_sr could be changed from 2 to 5 for E-AC-3 once we find a
2224  decoder that supports half sample rate so we can validate that
2225  the generated files are correct. */
2226  max_sr = s->eac3 ? 2 : 8;
2227  for (i = 0; i <= max_sr; i++) {
2228  if ((ff_ac3_sample_rate_tab[i % 3] >> (i / 3)) == avctx->sample_rate)
2229  break;
2230  }
2231  if (i > max_sr) {
2232  av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n");
2233  return AVERROR(EINVAL);
2234  }
2235  s->sample_rate = avctx->sample_rate;
2236  s->bit_alloc.sr_shift = i / 3;
2237  s->bit_alloc.sr_code = i % 3;
2238  s->bitstream_id = s->eac3 ? 16 : 8 + s->bit_alloc.sr_shift;
2239 
2240  /* select a default bit rate if not set by the user */
2241  if (!avctx->bit_rate) {
2242  switch (s->fbw_channels) {
2243  case 1: avctx->bit_rate = 96000; break;
2244  case 2: avctx->bit_rate = 192000; break;
2245  case 3: avctx->bit_rate = 320000; break;
2246  case 4: avctx->bit_rate = 384000; break;
2247  case 5: avctx->bit_rate = 448000; break;
2248  }
2249  }
2250 
2251  /* validate bit rate */
2252  if (s->eac3) {
2253  int max_br, min_br, wpf, min_br_code;
2254  int num_blks_code, num_blocks, frame_samples;
2255  long long min_br_dist;
2256 
2257  /* calculate min/max bitrate */
2258  /* TODO: More testing with 3 and 2 blocks. All E-AC-3 samples I've
2259  found use either 6 blocks or 1 block, even though 2 or 3 blocks
2260  would work as far as the bit rate is concerned. */
2261  for (num_blks_code = 3; num_blks_code >= 0; num_blks_code--) {
2262  num_blocks = ((int[]){ 1, 2, 3, 6 })[num_blks_code];
2263  frame_samples = AC3_BLOCK_SIZE * num_blocks;
2264  max_br = 2048 * s->sample_rate / frame_samples * 16;
2265  min_br = ((s->sample_rate + (frame_samples-1)) / frame_samples) * 16;
2266  if (avctx->bit_rate <= max_br)
2267  break;
2268  }
2269  if (avctx->bit_rate < min_br || avctx->bit_rate > max_br) {
2270  av_log(avctx, AV_LOG_ERROR, "invalid bit rate. must be %d to %d "
2271  "for this sample rate\n", min_br, max_br);
2272  return AVERROR(EINVAL);
2273  }
2274  s->num_blks_code = num_blks_code;
2275  s->num_blocks = num_blocks;
2276 
2277  /* calculate words-per-frame for the selected bitrate */
2278  wpf = (avctx->bit_rate / 16) * frame_samples / s->sample_rate;
2279  av_assert1(wpf > 0 && wpf <= 2048);
2280 
2281  /* find the closest AC-3 bitrate code to the selected bitrate.
2282  this is needed for lookup tables for bandwidth and coupling
2283  parameter selection */
2284  min_br_code = -1;
2285  min_br_dist = INT64_MAX;
2286  for (i = 0; i < 19; i++) {
2287  long long br_dist = llabs(ff_ac3_bitrate_tab[i] * 1000 - avctx->bit_rate);
2288  if (br_dist < min_br_dist) {
2289  min_br_dist = br_dist;
2290  min_br_code = i;
2291  }
2292  }
2293 
2294  /* make sure the minimum frame size is below the average frame size */
2295  s->frame_size_code = min_br_code << 1;
2296  while (wpf > 1 && wpf * s->sample_rate / AC3_FRAME_SIZE * 16 > avctx->bit_rate)
2297  wpf--;
2298  s->frame_size_min = 2 * wpf;
2299  } else {
2300  int best_br = 0, best_code = 0;
2301  long long best_diff = INT64_MAX;
2302  for (i = 0; i < 19; i++) {
2303  int br = (ff_ac3_bitrate_tab[i] >> s->bit_alloc.sr_shift) * 1000;
2304  long long diff = llabs(br - avctx->bit_rate);
2305  if (diff < best_diff) {
2306  best_br = br;
2307  best_code = i;
2308  best_diff = diff;
2309  }
2310  if (!best_diff)
2311  break;
2312  }
2313  avctx->bit_rate = best_br;
2314  s->frame_size_code = best_code << 1;
2315  s->frame_size_min = 2 * ff_ac3_frame_size_tab[s->frame_size_code][s->bit_alloc.sr_code];
2316  s->num_blks_code = 0x3;
2317  s->num_blocks = 6;
2318  }
2319  s->bit_rate = avctx->bit_rate;
2320  s->frame_size = s->frame_size_min;
2321 
2322  /* validate cutoff */
2323  if (avctx->cutoff < 0) {
2324  av_log(avctx, AV_LOG_ERROR, "invalid cutoff frequency\n");
2325  return AVERROR(EINVAL);
2326  }
2327  s->cutoff = avctx->cutoff;
2328  if (s->cutoff > (s->sample_rate >> 1))
2329  s->cutoff = s->sample_rate >> 1;
2330 
2331  ret = ff_ac3_validate_metadata(s);
2332  if (ret)
2333  return ret;
2334 
2335  s->rematrixing_enabled = s->options.stereo_rematrixing &&
2336  (s->channel_mode == AC3_CHMODE_STEREO);
2337 
2338  s->cpl_enabled = s->options.channel_coupling &&
2339  s->channel_mode >= AC3_CHMODE_STEREO;
2340 
2341  return 0;
2342 }
2343 
2344 
2345 /*
2346  * Set bandwidth for all channels.
2347  * The user can optionally supply a cutoff frequency. Otherwise an appropriate
2348  * default value will be used.
2349  */
2351 {
2352  int blk, ch, av_uninit(cpl_start);
2353 
2354  if (s->cutoff) {
2355  /* calculate bandwidth based on user-specified cutoff frequency */
2356  int fbw_coeffs;
2357  fbw_coeffs = s->cutoff * 2 * AC3_MAX_COEFS / s->sample_rate;
2358  s->bandwidth_code = av_clip((fbw_coeffs - 73) / 3, 0, 60);
2359  } else {
2360  /* use default bandwidth setting */
2361  s->bandwidth_code = ac3_bandwidth_tab[s->fbw_channels-1][s->bit_alloc.sr_code][s->frame_size_code/2];
2362  }
2363 
2364  /* set number of coefficients for each channel */
2365  for (ch = 1; ch <= s->fbw_channels; ch++) {
2366  s->start_freq[ch] = 0;
2367  for (blk = 0; blk < s->num_blocks; blk++)
2368  s->blocks[blk].end_freq[ch] = s->bandwidth_code * 3 + 73;
2369  }
2370  /* LFE channel always has 7 coefs */
2371  if (s->lfe_on) {
2372  s->start_freq[s->lfe_channel] = 0;
2373  for (blk = 0; blk < s->num_blocks; blk++)
2374  s->blocks[blk].end_freq[ch] = 7;
2375  }
2376 
2377  /* initialize coupling strategy */
2378  if (s->cpl_enabled) {
2379  if (s->options.cpl_start != AC3ENC_OPT_AUTO) {
2380  cpl_start = s->options.cpl_start;
2381  } else {
2382  cpl_start = ac3_coupling_start_tab[s->channel_mode-2][s->bit_alloc.sr_code][s->frame_size_code/2];
2383  if (cpl_start < 0) {
2384  if (s->options.channel_coupling == AC3ENC_OPT_AUTO)
2385  s->cpl_enabled = 0;
2386  else
2387  cpl_start = 15;
2388  }
2389  }
2390  }
2391  if (s->cpl_enabled) {
2392  int i, cpl_start_band, cpl_end_band;
2393  uint8_t *cpl_band_sizes = s->cpl_band_sizes;
2394 
2395  cpl_end_band = s->bandwidth_code / 4 + 3;
2396  cpl_start_band = av_clip(cpl_start, 0, FFMIN(cpl_end_band-1, 15));
2397 
2398  s->num_cpl_subbands = cpl_end_band - cpl_start_band;
2399 
2400  s->num_cpl_bands = 1;
2401  *cpl_band_sizes = 12;
2402  for (i = cpl_start_band + 1; i < cpl_end_band; i++) {
2404  *cpl_band_sizes += 12;
2405  } else {
2406  s->num_cpl_bands++;
2407  cpl_band_sizes++;
2408  *cpl_band_sizes = 12;
2409  }
2410  }
2411 
2412  s->start_freq[CPL_CH] = cpl_start_band * 12 + 37;
2413  s->cpl_end_freq = cpl_end_band * 12 + 37;
2414  for (blk = 0; blk < s->num_blocks; blk++)
2415  s->blocks[blk].end_freq[CPL_CH] = s->cpl_end_freq;
2416  }
2417 }
2418 
2419 
2421 {
2422  int blk, ch;
2423  int channels = s->channels + 1; /* includes coupling channel */
2424  int channel_blocks = channels * s->num_blocks;
2425  int total_coefs = AC3_MAX_COEFS * channel_blocks;
2426 
2427  if (s->allocate_sample_buffers(s))
2428  return AVERROR(ENOMEM);
2429 
2430  if (!FF_ALLOC_TYPED_ARRAY(s->bap_buffer, total_coefs) ||
2431  !FF_ALLOC_TYPED_ARRAY(s->bap1_buffer, total_coefs) ||
2432  !FF_ALLOCZ_TYPED_ARRAY(s->mdct_coef_buffer, total_coefs) ||
2433  !FF_ALLOC_TYPED_ARRAY(s->exp_buffer, total_coefs) ||
2434  !FF_ALLOC_TYPED_ARRAY(s->grouped_exp_buffer, channel_blocks * 128) ||
2435  !FF_ALLOC_TYPED_ARRAY(s->psd_buffer, total_coefs) ||
2436  !FF_ALLOC_TYPED_ARRAY(s->band_psd_buffer, channel_blocks * 64) ||
2437  !FF_ALLOC_TYPED_ARRAY(s->mask_buffer, channel_blocks * 64) ||
2438  !FF_ALLOC_TYPED_ARRAY(s->qmant_buffer, total_coefs))
2439  return AVERROR(ENOMEM);
2440 
2441  if (s->cpl_enabled) {
2442  if (!FF_ALLOC_TYPED_ARRAY(s->cpl_coord_exp_buffer, channel_blocks * 16) ||
2443  !FF_ALLOC_TYPED_ARRAY(s->cpl_coord_mant_buffer, channel_blocks * 16))
2444  return AVERROR(ENOMEM);
2445  }
2446  for (blk = 0; blk < s->num_blocks; blk++) {
2447  AC3Block *block = &s->blocks[blk];
2448 
2449  if (!FF_ALLOCZ_TYPED_ARRAY(block->mdct_coef, channels) ||
2451  !FF_ALLOCZ_TYPED_ARRAY(block->grouped_exp, channels) ||
2453  !FF_ALLOCZ_TYPED_ARRAY(block->band_psd, channels) ||
2456  return AVERROR(ENOMEM);
2457 
2458  if (s->cpl_enabled) {
2459  if (!FF_ALLOCZ_TYPED_ARRAY(block->cpl_coord_exp, channels) ||
2460  !FF_ALLOCZ_TYPED_ARRAY(block->cpl_coord_mant, channels))
2461  return AVERROR(ENOMEM);
2462  }
2463 
2464  for (ch = 0; ch < channels; ch++) {
2465  /* arrangement: block, channel, coeff */
2466  block->grouped_exp[ch] = &s->grouped_exp_buffer[128 * (blk * channels + ch)];
2467  block->psd[ch] = &s->psd_buffer [AC3_MAX_COEFS * (blk * channels + ch)];
2468  block->band_psd[ch] = &s->band_psd_buffer [64 * (blk * channels + ch)];
2469  block->mask[ch] = &s->mask_buffer [64 * (blk * channels + ch)];
2470  block->qmant[ch] = &s->qmant_buffer [AC3_MAX_COEFS * (blk * channels + ch)];
2471  if (s->cpl_enabled) {
2472  block->cpl_coord_exp[ch] = &s->cpl_coord_exp_buffer [16 * (blk * channels + ch)];
2473  block->cpl_coord_mant[ch] = &s->cpl_coord_mant_buffer[16 * (blk * channels + ch)];
2474  }
2475 
2476  /* arrangement: channel, block, coeff */
2477  block->exp[ch] = &s->exp_buffer [AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2478  block->mdct_coef[ch] = &s->mdct_coef_buffer [AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2479  }
2480  }
2481 
2482  if (!s->fixed_point) {
2483  if (!FF_ALLOCZ_TYPED_ARRAY(s->fixed_coef_buffer, total_coefs))
2484  return AVERROR(ENOMEM);
2485  for (blk = 0; blk < s->num_blocks; blk++) {
2486  AC3Block *block = &s->blocks[blk];
2487  if (!FF_ALLOCZ_TYPED_ARRAY(block->fixed_coef, channels))
2488  return AVERROR(ENOMEM);
2489  for (ch = 0; ch < channels; ch++)
2490  block->fixed_coef[ch] = &s->fixed_coef_buffer[AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2491  }
2492  } else {
2493  for (blk = 0; blk < s->num_blocks; blk++) {
2494  AC3Block *block = &s->blocks[blk];
2495  if (!FF_ALLOCZ_TYPED_ARRAY(block->fixed_coef, channels))
2496  return AVERROR(ENOMEM);
2497  for (ch = 0; ch < channels; ch++)
2498  block->fixed_coef[ch] = (int32_t *)block->mdct_coef[ch];
2499  }
2500  }
2501 
2502  return 0;
2503 }
2504 
2505 
2507 {
2508  static AVOnce init_static_once = AV_ONCE_INIT;
2509  AC3EncodeContext *s = avctx->priv_data;
2510  int ret, frame_size_58;
2511 
2512  s->avctx = avctx;
2513 
2514  s->eac3 = avctx->codec_id == AV_CODEC_ID_EAC3;
2515 
2516  ret = validate_options(s);
2517  if (ret)
2518  return ret;
2519 
2520  avctx->frame_size = AC3_BLOCK_SIZE * s->num_blocks;
2522 
2523  s->bitstream_mode = avctx->audio_service_type;
2524  if (s->bitstream_mode == AV_AUDIO_SERVICE_TYPE_KARAOKE)
2525  s->bitstream_mode = 0x7;
2526 
2527  s->bits_written = 0;
2528  s->samples_written = 0;
2529 
2530  /* calculate crc_inv for both possible frame sizes */
2531  frame_size_58 = (( s->frame_size >> 2) + ( s->frame_size >> 4)) << 1;
2532  s->crc_inv[0] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);
2533  if (s->bit_alloc.sr_code == 1) {
2534  frame_size_58 = (((s->frame_size+2) >> 2) + ((s->frame_size+2) >> 4)) << 1;
2535  s->crc_inv[1] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);
2536  }
2537 
2538  if (CONFIG_EAC3_ENCODER && s->eac3) {
2539  static AVOnce init_static_once_eac3 = AV_ONCE_INIT;
2540  ff_thread_once(&init_static_once_eac3, ff_eac3_exponent_init);
2541  s->output_frame_header = ff_eac3_output_frame_header;
2542  } else
2543  s->output_frame_header = ac3_output_frame_header;
2544 
2545  set_bandwidth(s);
2546 
2547  bit_alloc_init(s);
2548 
2549  ret = s->mdct_init(s);
2550  if (ret)
2551  return ret;
2552 
2553  ret = allocate_buffers(s);
2554  if (ret)
2555  return ret;
2556 
2557  ff_audiodsp_init(&s->adsp);
2558  ff_me_cmp_init(&s->mecc, avctx);
2559  ff_ac3dsp_init(&s->ac3dsp, avctx->flags & AV_CODEC_FLAG_BITEXACT);
2560 
2561  dprint_options(s);
2562 
2563  ff_thread_once(&init_static_once, exponent_init);
2564 
2565  return 0;
2566 }
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:118
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:92
Common code between the AC-3 encoder and decoder.
#define LEVEL_PLUS_1POINT5DB
Definition: ac3.h:106
#define EXP_D25
Definition: ac3.h:51
#define EXP_REUSE
Definition: ac3.h:47
#define EXP_D45
Definition: ac3.h:52
#define EXP_D15
Definition: ac3.h:50
#define CPL_CH
coupling channel index
Definition: ac3.h:32
#define EXP_NEW
Definition: ac3.h:48
#define AC3_MAX_CHANNELS
maximum number of channels, including coupling channel
Definition: ac3.h:31
#define LEVEL_MINUS_3DB
Definition: ac3.h:108
#define LEVEL_ONE
Definition: ac3.h:113
#define AC3_BLOCK_SIZE
Definition: ac3.h:35
#define LEVEL_MINUS_1POINT5DB
Definition: ac3.h:107
@ AC3_CHMODE_MONO
Definition: ac3.h:126
@ AC3_CHMODE_STEREO
Definition: ac3.h:127
@ AC3_CHMODE_2F1R
Definition: ac3.h:129
@ AC3_CHMODE_3F
Definition: ac3.h:128
@ AC3_CHMODE_3F1R
Definition: ac3.h:130
@ AC3_CHMODE_2F2R
Definition: ac3.h:131
@ AC3_CHMODE_3F2R
Definition: ac3.h:132
#define AC3_FRAME_SIZE
Definition: ac3.h:37
@ DBA_NONE
Definition: ac3.h:119
#define AC3_MAX_BLOCKS
Definition: ac3.h:36
#define LEVEL_ZERO
Definition: ac3.h:112
#define LEVEL_PLUS_3DB
Definition: ac3.h:105
#define LEVEL_MINUS_4POINT5DB
Definition: ac3.h:109
#define AC3_MAX_COEFS
Definition: ac3.h:34
#define LEVEL_MINUS_6DB
Definition: ac3.h:110
av_cold void ff_ac3dsp_init(AC3DSPContext *c, int bit_exact)
Definition: ac3dsp.c:368
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:212
static void count_mantissa_bits_init(uint16_t mant_cnt[AC3_MAX_BLOCKS][16])
Initialize mantissa counts.
Definition: ac3enc.c:1063
#define AC3ENC_PARAM
Definition: ac3enc.c:76
static void ac3_group_exponents(AC3EncodeContext *s)
Group exponents.
Definition: ac3enc.c:646
static int validate_float_option(float v, const float *v_list, int v_list_size)
Definition: ac3enc.c:1890
av_cold int ff_ac3_encode_close(AVCodecContext *avctx)
Finalize encoding and free any memory allocated by the encoder.
Definition: ac3enc.c:2113
static void compute_exp_strategy(AC3EncodeContext *s)
Definition: ac3enc.c:425
static void extract_exponents(AC3EncodeContext *s)
Definition: ac3enc.c:395
#define CRC16_POLY
CRC-16 Polynomial.
Definition: ac3enc.c:1642
#define FLT_OPTION_THRESHOLD
Definition: ac3enc.c:1888
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:414
static void dprint_options(AC3EncodeContext *s)
Definition: ac3enc.c:1773
static av_cold void bit_alloc_init(AC3EncodeContext *s)
Definition: ac3enc.c:826
static void ac3_process_exponents(AC3EncodeContext *s)
Calculate final exponents from the supplied MDCT coefficients and exponent shift.
Definition: ac3enc.c:704
static av_cold int allocate_buffers(AC3EncodeContext *s)
Definition: ac3enc.c:2420
#define SURMIXLEV_NUM_OPTIONS
Definition: ac3enc.c:61
static void output_audio_block(AC3EncodeContext *s, int blk)
Definition: ac3enc.c:1452
static uint8_t exponent_group_tab[2][3][256]
LUT for number of exponent groups.
Definition: ac3enc.c:136
#define OFFSET(param)
Definition: ac3enc.c:75
#define CMIXLEV_NUM_OPTIONS
Definition: ac3enc.c:56
av_cold int ff_ac3_encode_init(AVCodecContext *avctx)
Definition: ac3enc.c:2506
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:168
static av_cold int set_channel_info(AC3EncodeContext *s, int channels, uint64_t *channel_layout)
Definition: ac3enc.c:2160
int ff_ac3_validate_metadata(AC3EncodeContext *s)
Validate metadata options as set by AVOption system.
Definition: ac3enc.c:1930
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:253
static const float cmixlev_options[CMIXLEV_NUM_OPTIONS]
Definition: ac3enc.c:57
const AVCodecDefault ff_ac3_enc_defaults[]
Definition: ac3enc.c:127
void ff_ac3_compute_coupling_strategy(AC3EncodeContext *s)
Set the initial coupling strategy parameters prior to coupling analysis.
Definition: ac3enc.c:271
static int bit_alloc(AC3EncodeContext *s, int snr_offset)
Run the bit allocation with a given SNR offset.
Definition: ac3enc.c:1131
static void reset_block_bap(AC3EncodeContext *s)
Definition: ac3enc.c:1038
static void encode_exponents(AC3EncodeContext *s)
Definition: ac3enc.c:564
static void count_frame_bits(AC3EncodeContext *s)
Definition: ac3enc.c:862
const AVOption ff_ac3_enc_options[]
Definition: ac3enc.c:77
static int asym_quant(int c, int e, int qbits)
Asymmetric quantization on 2^qbits levels.
Definition: ac3enc.c:1249
static int sym_quant(int c, int e, int levels)
Symmetric quantization on 'levels' levels.
Definition: ac3enc.c:1233
static av_cold void set_bandwidth(AC3EncodeContext *s)
Definition: ac3enc.c:2350
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:491
static void ac3_output_frame(AC3EncodeContext *s, unsigned char *frame)
Write the frame to the output bitstream.
Definition: ac3enc.c:1728
static void output_frame_end(AC3EncodeContext *s)
Definition: ac3enc.c:1679
static void bit_alloc_masking(AC3EncodeContext *s)
Definition: ac3enc.c:1008
static av_cold int validate_options(AC3EncodeContext *s)
Definition: ac3enc.c:2205
static void ac3_output_frame_header(AC3EncodeContext *s)
Definition: ac3enc.c:1396
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:1273
static void count_frame_bits_fixed(AC3EncodeContext *s)
Definition: ac3enc.c:720
#define EXP_DIFF_THRESHOLD
Exponent Difference Threshold.
Definition: ac3enc.c:409
int ff_ac3_encode_frame_common_end(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr)
Definition: ac3enc.c:1742
static const float surmixlev_options[SURMIXLEV_NUM_OPTIONS]
Definition: ac3enc.c:62
static void ac3_quantize_mantissas(AC3EncodeContext *s)
Quantize mantissas using coefficients, exponents, and bit allocation pointers.
Definition: ac3enc.c:1367
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:179
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:1085
static av_cold void exponent_init(void)
Definition: ac3enc.c:376
static const float extmixlev_options[EXTMIXLEV_NUM_OPTIONS]
Definition: ac3enc.c:67
static int count_mantissa_bits(AC3EncodeContext *s)
Definition: ac3enc.c:1105
static int cbr_bit_allocation(AC3EncodeContext *s)
Definition: ac3enc.c:1162
static int count_exponent_bits(AC3EncodeContext *s)
Definition: ac3enc.c:614
static int ac3_compute_bit_allocation(AC3EncodeContext *s)
Definition: ac3enc.c:1213
#define EXTMIXLEV_NUM_OPTIONS
Definition: ac3enc.c:66
static unsigned int pow_poly(unsigned int a, unsigned int n, unsigned int poly)
Definition: ac3enc.c:1662
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:1906
static void ac3_apply_rematrixing(AC3EncodeContext *s)
Apply stereo rematrixing to coefficients based on rematrixing flags.
Definition: ac3enc.c:342
const uint64_t ff_ac3_channel_layouts[19]
List of supported channel layouts.
Definition: ac3enc.c:142
static unsigned int mul_poly(unsigned int a, unsigned int b, unsigned int poly)
Definition: ac3enc.c:1645
AC-3 encoder & E-AC-3 encoder common header.
#define AC3ENC_OPT_ADCONV_STANDARD
Definition: ac3enc.h:84
#define AC3ENC_OPT_DOWNMIX_LORO
Definition: ac3enc.h:82
#define AC3ENC_OPT_DOWNMIX_LTRT
Definition: ac3enc.h:81
#define AC3ENC_OPT_DOWNMIX_DPLII
Definition: ac3enc.h:83
#define AC3ENC_OPT_LARGE_ROOM
Definition: ac3enc.h:79
#define AC3ENC_OPT_AUTO
Definition: ac3enc.h:70
#define AC3ENC_OPT_ADCONV_HDCD
Definition: ac3enc.h:85
#define AC3ENC_OPT_NONE
Definition: ac3enc.h:69
#define AC3ENC_OPT_OFF
Definition: ac3enc.h:71
#define AC3ENC_OPT_ON
Definition: ac3enc.h:72
#define AC3ENC_OPT_SMALL_ROOM
Definition: ac3enc.h:80
#define AC3ENC_OPT_MODE_OFF
Definition: ac3enc.h:75
#define AC3ENC_OPT_DSUREX_DPLIIZ
Definition: ac3enc.h:76
#define AC3ENC_OPT_MODE_ON
Definition: ac3enc.h:74
#define AC3ENC_OPT_NOT_INDICATED
Definition: ac3enc.h:73
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:123
const uint16_t ff_ac3_bitrate_tab[19]
Definition: ac3tab.c:114
const uint8_t ff_ac3_fast_decay_tab[4]
Definition: ac3tab.c:228
const int ff_ac3_sample_rate_tab[]
Definition: ac3tab.c:111
const uint16_t ff_ac3_fast_gain_tab[8]
Definition: ac3tab.c:244
const uint16_t ff_ac3_slow_gain_tab[4]
Definition: ac3tab.c:232
const uint8_t ff_eac3_default_cpl_band_struct[18]
Table E2.16 Default Coupling Banding Structure.
Definition: ac3tab.c:128
const uint16_t ff_ac3_frame_size_tab[38][3]
Possible frame sizes.
Definition: ac3tab.c:37
const uint8_t ff_ac3_slow_decay_tab[4]
Definition: ac3tab.c:224
const int16_t ff_ac3_floor_tab[8]
Definition: ac3tab.c:240
const uint16_t ff_ac3_db_per_bit_tab[4]
Definition: ac3tab.c:236
const uint8_t ff_ac3_bap_tab[64]
Definition: ac3tab.c:214
#define COMMON_CHANNEL_MAP
Definition: ac3tab.h:68
channels
Definition: aptx.h:33
Macro definitions for various function/variable attributes.
#define av_uninit(x)
Definition: attributes.h:154
#define av_cold
Definition: attributes.h:88
uint8_t
int32_t
simple assert() macros that are a bit more flexible than ISO C assert().
#define av_assert2(cond)
assert() equivalent, that does lie in speed critical code.
Definition: avassert.h:64
#define av_assert1(cond)
assert() equivalent, that does not lie in speed critical code.
Definition: avassert.h:53
Libavcodec external API header.
#define flags(name, subs,...)
Definition: cbs_av1.c:572
#define s(width, name)
Definition: cbs_vp9.c:257
audio channel layout utility functions
#define FFSWAP(type, a, b)
Definition: common.h:108
#define FFMIN(a, b)
Definition: common.h:105
#define av_clip
Definition: common.h:122
#define CONFIG_EAC3_ENCODER
Definition: config.h:1389
#define NULL
Definition: coverity.c:32
Public header for CRC hash function implementation.
static AVFrame * frame
void ff_eac3_output_frame_header(AC3EncodeContext *s)
Write the E-AC-3 frame header to the output bitstream.
Definition: eac3enc.c:125
void ff_eac3_get_frame_exp_strategy(AC3EncodeContext *s)
Determine frame exponent strategy use and indices.
Definition: eac3enc.c:65
av_cold void ff_eac3_exponent_init(void)
Initialize E-AC-3 exponent tables.
Definition: eac3enc.c:49
E-AC-3 encoder.
int ff_alloc_packet2(AVCodecContext *avctx, AVPacket *avpkt, int64_t size, int64_t min_size)
Check AVPacket size and/or allocate data.
Definition: encode.c:33
int8_t exp
Definition: eval.c:72
@ AV_OPT_TYPE_CONST
Definition: opt.h:234
@ AV_OPT_TYPE_INT
Definition: opt.h:225
@ AV_OPT_TYPE_FLOAT
Definition: opt.h:228
@ AV_OPT_TYPE_BOOL
Definition: opt.h:242
#define AV_CH_LAYOUT_QUAD
#define AV_CH_LAYOUT_4POINT0
#define AV_CH_LAYOUT_5POINT0
#define AV_CH_LAYOUT_MONO
#define AV_CH_LAYOUT_2_2
#define AV_CH_LAYOUT_SURROUND
void av_get_channel_layout_string(char *buf, int buf_size, int nb_channels, uint64_t channel_layout)
Return a description of a channel layout.
#define AV_CH_LAYOUT_5POINT0_BACK
#define AV_CH_LAYOUT_STEREO
#define AV_CH_LAYOUT_5POINT1
int64_t av_get_default_channel_layout(int nb_channels)
Return default channel layout for a given number of channels.
#define AV_CH_LAYOUT_2_1
#define AV_CH_LAYOUT_5POINT1_BACK
#define AV_CH_LOW_FREQUENCY
#define AV_CODEC_FLAG_BITEXACT
Use only bitexact stuff (except (I)DCT).
Definition: avcodec.h:333
@ AV_CODEC_ID_EAC3
Definition: codec_id.h:464
@ AV_AUDIO_SERVICE_TYPE_VOICE_OVER
Definition: avcodec.h:247
@ AV_AUDIO_SERVICE_TYPE_EMERGENCY
Definition: avcodec.h:246
@ AV_AUDIO_SERVICE_TYPE_MAIN
Definition: avcodec.h:240
@ AV_AUDIO_SERVICE_TYPE_KARAOKE
Definition: avcodec.h:248
@ AV_AUDIO_SERVICE_TYPE_COMMENTARY
Definition: avcodec.h:245
const AVCRC * av_crc_get_table(AVCRCId crc_id)
Get an initialized standard CRC table.
Definition: crc.c:374
uint32_t AVCRC
Definition: crc.h:47
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
@ AV_CRC_16_ANSI
Definition: crc.h:51
#define AVERROR(e)
Definition: error.h:43
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:200
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
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:49
size_t av_strlcpy(char *dst, const char *src, size_t size)
Copy the string src to dst, but no more than size - 1 bytes, and null-terminate dst.
Definition: avstring.c:83
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
int i
Definition: input.c:407
#define AV_WB16(p, v)
Definition: intreadwrite.h:405
static void put_bits(Jpeg2000EncoderContext *s, int val, int n)
put n times val bit
Definition: j2kenc.c:218
av_cold void ff_audiodsp_init(AudioDSPContext *c)
Definition: audiodsp.c:106
static av_always_inline int64_t ff_samples_to_time_base(AVCodecContext *avctx, int64_t samples)
Rescale from sample rate to AVCodecContext.time_base.
Definition: internal.h:277
common internal API header
#define FF_ALLOC_TYPED_ARRAY(p, nelem)
Definition: internal.h:102
#define emms_c()
Definition: internal.h:54
#define FF_ALLOCZ_TYPED_ARRAY(p, nelem)
Definition: internal.h:103
#define AVOnce
Definition: thread.h:172
static int ff_thread_once(char *control, void(*routine)(void))
Definition: thread.h:175
#define AV_ONCE_INIT
Definition: thread.h:173
av_cold void ff_me_cmp_init(MECmpContext *c, AVCodecContext *avctx)
Definition: me_cmp.c:1015
#define LOCAL_ALIGNED_16(t, v,...)
Definition: mem_internal.h:130
AVOptions.
bitstream writer API
static void put_sbits(PutBitContext *pb, int n, int32_t value)
Definition: put_bits.h:253
static void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
Initialize the PutBitContext s.
Definition: put_bits.h:57
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:342
static int put_bits_count(PutBitContext *s)
Definition: put_bits.h:76
static void flush_put_bits(PutBitContext *s)
Pad the end of the output stream with zeros.
Definition: put_bits.h:110
#define av_bswap16
Definition: bswap.h:31
#define blk(i)
Definition: sha.c:185
#define snprintf
Definition: snprintf.h:34
Data for a single audio block.
Definition: ac3enc.h:126
Encoding Options used by AVOption.
Definition: ac3enc.h:91
float ltrt_surround_mix_level
Definition: ac3enc.h:106
int dialogue_level
Definition: ac3enc.h:93
float surround_mix_level
Definition: ac3enc.h:96
int dolby_surround_ex_mode
Definition: ac3enc.h:110
int eac3_mixing_metadata
Definition: ac3enc.h:113
int dolby_headphone_mode
Definition: ac3enc.h:111
int extended_bsi_2
Definition: ac3enc.h:109
float loro_surround_mix_level
Definition: ac3enc.h:108
int audio_production_info
Definition: ac3enc.h:98
int allow_per_frame_metadata
Definition: ac3enc.h:117
int dolby_surround_mode
Definition: ac3enc.h:97
int original
Definition: ac3enc.h:102
int room_type
Definition: ac3enc.h:100
int extended_bsi_1
Definition: ac3enc.h:103
int copyright
Definition: ac3enc.h:101
float loro_center_mix_level
Definition: ac3enc.h:107
int eac3_info_metadata
Definition: ac3enc.h:114
int ad_converter_type
Definition: ac3enc.h:112
int preferred_stereo_downmix
Definition: ac3enc.h:104
float ltrt_center_mix_level
Definition: ac3enc.h:105
int mixing_level
Definition: ac3enc.h:99
float center_mix_level
Definition: ac3enc.h:95
AC-3 encoder private context.
Definition: ac3enc.h:154
Definition: ac3enc.c:51
int mant4_cnt
mantissa counts for bap=1,2,4
Definition: ac3enc.c:53
int mant2_cnt
Definition: ac3enc.c:53
int16_t * qmant2_ptr
Definition: ac3enc.c:52
int16_t * qmant4_ptr
mantissa pointers for bap=1,2,4
Definition: ac3enc.c:52
int16_t * qmant1_ptr
Definition: ac3enc.c:52
int mant1_cnt
Definition: ac3enc.c:53
main external API structure.
Definition: avcodec.h:536
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1204
enum AVAudioServiceType audio_service_type
Type of service that the audio stream conveys.
Definition: avcodec.h:1261
int64_t bit_rate
the average bitrate
Definition: avcodec.h:586
int initial_padding
Audio only.
Definition: avcodec.h:2066
int sample_rate
samples per second
Definition: avcodec.h:1196
int flags
AV_CODEC_FLAG_*.
Definition: avcodec.h:616
int channels
number of audio channels
Definition: avcodec.h:1197
enum AVCodecID codec_id
Definition: avcodec.h:546
int cutoff
Audio cutoff bandwidth (0 means "automatic")
Definition: avcodec.h:1240
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:1247
int frame_size
Number of samples per channel in an audio frame.
Definition: avcodec.h:1216
void * priv_data
Definition: avcodec.h:563
This structure describes decoded (raw) audio or video data.
Definition: frame.h:318
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:411
AVOption.
Definition: opt.h:248
This structure stores compressed data.
Definition: packet.h:346
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:362
uint8_t * data
Definition: packet.h:369
#define ff_dlog(a,...)
#define av_freep(p)
#define av_log(a,...)
static int16_t block[64]
Definition: dct.c:116
const char * b
Definition: vf_curves.c:118
const char * r
Definition: vf_curves.c:116
if(ret< 0)
Definition: vf_mcdeint.c:282
static av_always_inline int diff(const uint32_t a, const uint32_t b)
static double c[64]