• Main Page
  • Related Pages
  • Modules
  • Data Structures
  • Files
  • File List
  • Globals

libavcodec/ac3enc.c

Go to the documentation of this file.
00001 /*
00002  * The simplest AC-3 encoder
00003  * Copyright (c) 2000 Fabrice Bellard
00004  * Copyright (c) 2006-2010 Justin Ruggles <justin.ruggles@gmail.com>
00005  * Copyright (c) 2006-2010 Prakash Punnoor <prakash@punnoor.de>
00006  *
00007  * This file is part of FFmpeg.
00008  *
00009  * FFmpeg is free software; you can redistribute it and/or
00010  * modify it under the terms of the GNU Lesser General Public
00011  * License as published by the Free Software Foundation; either
00012  * version 2.1 of the License, or (at your option) any later version.
00013  *
00014  * FFmpeg is distributed in the hope that it will be useful,
00015  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00016  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00017  * Lesser General Public License for more details.
00018  *
00019  * You should have received a copy of the GNU Lesser General Public
00020  * License along with FFmpeg; if not, write to the Free Software
00021  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00022  */
00023 
00029 //#define ASSERT_LEVEL 2
00030 
00031 #include <stdint.h>
00032 
00033 #include "libavutil/audioconvert.h"
00034 #include "libavutil/avassert.h"
00035 #include "libavutil/avstring.h"
00036 #include "libavutil/crc.h"
00037 #include "libavutil/opt.h"
00038 #include "avcodec.h"
00039 #include "put_bits.h"
00040 #include "dsputil.h"
00041 #include "ac3dsp.h"
00042 #include "ac3.h"
00043 #include "audioconvert.h"
00044 #include "fft.h"
00045 #include "ac3enc.h"
00046 #include "eac3enc.h"
00047 
00048 typedef struct AC3Mant {
00049     int16_t *qmant1_ptr, *qmant2_ptr, *qmant4_ptr; 
00050     int mant1_cnt, mant2_cnt, mant4_cnt;    
00051 } AC3Mant;
00052 
00053 #define CMIXLEV_NUM_OPTIONS 3
00054 static const float cmixlev_options[CMIXLEV_NUM_OPTIONS] = {
00055     LEVEL_MINUS_3DB, LEVEL_MINUS_4POINT5DB, LEVEL_MINUS_6DB
00056 };
00057 
00058 #define SURMIXLEV_NUM_OPTIONS 3
00059 static const float surmixlev_options[SURMIXLEV_NUM_OPTIONS] = {
00060     LEVEL_MINUS_3DB, LEVEL_MINUS_6DB, LEVEL_ZERO
00061 };
00062 
00063 #define EXTMIXLEV_NUM_OPTIONS 8
00064 static const float extmixlev_options[EXTMIXLEV_NUM_OPTIONS] = {
00065     LEVEL_PLUS_3DB,  LEVEL_PLUS_1POINT5DB,  LEVEL_ONE,       LEVEL_MINUS_4POINT5DB,
00066     LEVEL_MINUS_3DB, LEVEL_MINUS_4POINT5DB, LEVEL_MINUS_6DB, LEVEL_ZERO
00067 };
00068 
00069 
00074 static uint8_t exponent_group_tab[2][3][256];
00075 
00076 
00080 const uint64_t ff_ac3_channel_layouts[19] = {
00081      AV_CH_LAYOUT_MONO,
00082      AV_CH_LAYOUT_STEREO,
00083      AV_CH_LAYOUT_2_1,
00084      AV_CH_LAYOUT_SURROUND,
00085      AV_CH_LAYOUT_2_2,
00086      AV_CH_LAYOUT_QUAD,
00087      AV_CH_LAYOUT_4POINT0,
00088      AV_CH_LAYOUT_5POINT0,
00089      AV_CH_LAYOUT_5POINT0_BACK,
00090     (AV_CH_LAYOUT_MONO     | AV_CH_LOW_FREQUENCY),
00091     (AV_CH_LAYOUT_STEREO   | AV_CH_LOW_FREQUENCY),
00092     (AV_CH_LAYOUT_2_1      | AV_CH_LOW_FREQUENCY),
00093     (AV_CH_LAYOUT_SURROUND | AV_CH_LOW_FREQUENCY),
00094     (AV_CH_LAYOUT_2_2      | AV_CH_LOW_FREQUENCY),
00095     (AV_CH_LAYOUT_QUAD     | AV_CH_LOW_FREQUENCY),
00096     (AV_CH_LAYOUT_4POINT0  | AV_CH_LOW_FREQUENCY),
00097      AV_CH_LAYOUT_5POINT1,
00098      AV_CH_LAYOUT_5POINT1_BACK,
00099      0
00100 };
00101 
00102 
00108 static const uint8_t ac3_bandwidth_tab[5][3][19] = {
00109 //      32  40  48  56  64  80  96 112 128 160 192 224 256 320 384 448 512 576 640
00110 
00111     { {  0,  0,  0, 12, 16, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48 },
00112       {  0,  0,  0, 16, 20, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56 },
00113       {  0,  0,  0, 32, 40, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } },
00114 
00115     { {  0,  0,  0,  0,  0,  0,  0, 20, 24, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48 },
00116       {  0,  0,  0,  0,  0,  0,  4, 24, 28, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56 },
00117       {  0,  0,  0,  0,  0,  0, 20, 44, 52, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } },
00118 
00119     { {  0,  0,  0,  0,  0,  0,  0,  0,  0, 16, 24, 32, 40, 48, 48, 48, 48, 48, 48 },
00120       {  0,  0,  0,  0,  0,  0,  0,  0,  4, 20, 28, 36, 44, 56, 56, 56, 56, 56, 56 },
00121       {  0,  0,  0,  0,  0,  0,  0,  0, 20, 40, 48, 60, 60, 60, 60, 60, 60, 60, 60 } },
00122 
00123     { {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 12, 24, 32, 48, 48, 48, 48, 48, 48 },
00124       {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 16, 28, 36, 56, 56, 56, 56, 56, 56 },
00125       {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 32, 48, 60, 60, 60, 60, 60, 60, 60 } },
00126 
00127     { {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  8, 20, 32, 40, 48, 48, 48, 48 },
00128       {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 12, 24, 36, 44, 56, 56, 56, 56 },
00129       {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 28, 44, 60, 60, 60, 60, 60, 60 } }
00130 };
00131 
00132 
00141 static const int8_t ac3_coupling_start_tab[6][3][19] = {
00142 //      32  40  48  56  64  80  96 112 128 160 192 224 256 320 384 448 512 576 640
00143 
00144     // 2/0
00145     { {  0,  0,  0,  0,  0,  0,  0,  1,  1,  7,  8, 11, 12, -1, -1, -1, -1, -1, -1 },
00146       {  0,  0,  0,  0,  0,  0,  1,  3,  5,  7, 10, 12, 13, -1, -1, -1, -1, -1, -1 },
00147       {  0,  0,  0,  0,  1,  2,  2,  9, 13, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
00148 
00149     // 3/0
00150     { {  0,  0,  0,  0,  0,  0,  0,  0,  2,  2,  6,  9, 11, 12, 13, -1, -1, -1, -1 },
00151       {  0,  0,  0,  0,  0,  0,  0,  0,  2,  2,  6,  9, 11, 12, 13, -1, -1, -1, -1 },
00152       { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
00153 
00154     // 2/1 - untested
00155     { {  0,  0,  0,  0,  0,  0,  0,  0,  2,  2,  6,  9, 11, 12, 13, -1, -1, -1, -1 },
00156       {  0,  0,  0,  0,  0,  0,  0,  0,  2,  2,  6,  9, 11, 12, 13, -1, -1, -1, -1 },
00157       { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
00158 
00159     // 3/1
00160     { {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  3,  2, 10, 11, 11, 12, 12, 14, -1 },
00161       {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  3,  2, 10, 11, 11, 12, 12, 14, -1 },
00162       { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
00163 
00164     // 2/2 - untested
00165     { {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  3,  2, 10, 11, 11, 12, 12, 14, -1 },
00166       {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  3,  2, 10, 11, 11, 12, 12, 14, -1 },
00167       { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
00168 
00169     // 3/2
00170     { {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  1,  6,  8, 11, 12, 12, -1, -1 },
00171       {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  1,  6,  8, 11, 12, 12, -1, -1 },
00172       { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
00173 };
00174 
00175 
00182 void ff_ac3_adjust_frame_size(AC3EncodeContext *s)
00183 {
00184     while (s->bits_written >= s->bit_rate && s->samples_written >= s->sample_rate) {
00185         s->bits_written    -= s->bit_rate;
00186         s->samples_written -= s->sample_rate;
00187     }
00188     s->frame_size = s->frame_size_min +
00189                     2 * (s->bits_written * s->sample_rate < s->samples_written * s->bit_rate);
00190     s->bits_written    += s->frame_size * 8;
00191     s->samples_written += AC3_BLOCK_SIZE * s->num_blocks;
00192 }
00193 
00194 
00200 void ff_ac3_compute_coupling_strategy(AC3EncodeContext *s)
00201 {
00202     int blk, ch;
00203     int got_cpl_snr;
00204     int num_cpl_blocks;
00205 
00206     /* set coupling use flags for each block/channel */
00207     /* TODO: turn coupling on/off and adjust start band based on bit usage */
00208     for (blk = 0; blk < s->num_blocks; blk++) {
00209         AC3Block *block = &s->blocks[blk];
00210         for (ch = 1; ch <= s->fbw_channels; ch++)
00211             block->channel_in_cpl[ch] = s->cpl_on;
00212     }
00213 
00214     /* enable coupling for each block if at least 2 channels have coupling
00215        enabled for that block */
00216     got_cpl_snr = 0;
00217     num_cpl_blocks = 0;
00218     for (blk = 0; blk < s->num_blocks; blk++) {
00219         AC3Block *block = &s->blocks[blk];
00220         block->num_cpl_channels = 0;
00221         for (ch = 1; ch <= s->fbw_channels; ch++)
00222             block->num_cpl_channels += block->channel_in_cpl[ch];
00223         block->cpl_in_use = block->num_cpl_channels > 1;
00224         num_cpl_blocks += block->cpl_in_use;
00225         if (!block->cpl_in_use) {
00226             block->num_cpl_channels = 0;
00227             for (ch = 1; ch <= s->fbw_channels; ch++)
00228                 block->channel_in_cpl[ch] = 0;
00229         }
00230 
00231         block->new_cpl_strategy = !blk;
00232         if (blk) {
00233             for (ch = 1; ch <= s->fbw_channels; ch++) {
00234                 if (block->channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) {
00235                     block->new_cpl_strategy = 1;
00236                     break;
00237                 }
00238             }
00239         }
00240         block->new_cpl_leak = block->new_cpl_strategy;
00241 
00242         if (!blk || (block->cpl_in_use && !got_cpl_snr)) {
00243             block->new_snr_offsets = 1;
00244             if (block->cpl_in_use)
00245                 got_cpl_snr = 1;
00246         } else {
00247             block->new_snr_offsets = 0;
00248         }
00249     }
00250     if (!num_cpl_blocks)
00251         s->cpl_on = 0;
00252 
00253     /* set bandwidth for each channel */
00254     for (blk = 0; blk < s->num_blocks; blk++) {
00255         AC3Block *block = &s->blocks[blk];
00256         for (ch = 1; ch <= s->fbw_channels; ch++) {
00257             if (block->channel_in_cpl[ch])
00258                 block->end_freq[ch] = s->start_freq[CPL_CH];
00259             else
00260                 block->end_freq[ch] = s->bandwidth_code * 3 + 73;
00261         }
00262     }
00263 }
00264 
00265 
00271 void ff_ac3_apply_rematrixing(AC3EncodeContext *s)
00272 {
00273     int nb_coefs;
00274     int blk, bnd, i;
00275     int start, end;
00276     uint8_t *flags;
00277 
00278     if (!s->rematrixing_enabled)
00279         return;
00280 
00281     for (blk = 0; blk < s->num_blocks; blk++) {
00282         AC3Block *block = &s->blocks[blk];
00283         if (block->new_rematrixing_strategy)
00284             flags = block->rematrixing_flags;
00285         nb_coefs = FFMIN(block->end_freq[1], block->end_freq[2]);
00286         for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++) {
00287             if (flags[bnd]) {
00288                 start = ff_ac3_rematrix_band_tab[bnd];
00289                 end   = FFMIN(nb_coefs, ff_ac3_rematrix_band_tab[bnd+1]);
00290                 for (i = start; i < end; i++) {
00291                     int32_t lt = block->fixed_coef[1][i];
00292                     int32_t rt = block->fixed_coef[2][i];
00293                     block->fixed_coef[1][i] = (lt + rt) >> 1;
00294                     block->fixed_coef[2][i] = (lt - rt) >> 1;
00295                 }
00296             }
00297         }
00298     }
00299 }
00300 
00301 
00302 /*
00303  * Initialize exponent tables.
00304  */
00305 static av_cold void exponent_init(AC3EncodeContext *s)
00306 {
00307     int expstr, i, grpsize;
00308 
00309     for (expstr = EXP_D15-1; expstr <= EXP_D45-1; expstr++) {
00310         grpsize = 3 << expstr;
00311         for (i = 12; i < 256; i++) {
00312             exponent_group_tab[0][expstr][i] = (i + grpsize - 4) / grpsize;
00313             exponent_group_tab[1][expstr][i] = (i              ) / grpsize;
00314         }
00315     }
00316     /* LFE */
00317     exponent_group_tab[0][0][7] = 2;
00318 
00319     if (CONFIG_EAC3_ENCODER && s->eac3)
00320         ff_eac3_exponent_init();
00321 }
00322 
00323 
00324 /*
00325  * Extract exponents from the MDCT coefficients.
00326  */
00327 static void extract_exponents(AC3EncodeContext *s)
00328 {
00329     int ch        = !s->cpl_on;
00330     int chan_size = AC3_MAX_COEFS * s->num_blocks * (s->channels - ch + 1);
00331     AC3Block *block = &s->blocks[0];
00332 
00333     s->ac3dsp.extract_exponents(block->exp[ch], block->fixed_coef[ch], chan_size);
00334 }
00335 
00336 
00341 #define EXP_DIFF_THRESHOLD 500
00342 
00346 static const uint8_t exp_strategy_reuse_tab[4][6] = {
00347     { EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },
00348     { EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },
00349     { EXP_D25, EXP_D25, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },
00350     { EXP_D45, EXP_D25, EXP_D25, EXP_D15, EXP_D15, EXP_D15 }
00351 };
00352 
00353 /*
00354  * Calculate exponent strategies for all channels.
00355  * Array arrangement is reversed to simplify the per-channel calculation.
00356  */
00357 static void compute_exp_strategy(AC3EncodeContext *s)
00358 {
00359     int ch, blk, blk1;
00360 
00361     for (ch = !s->cpl_on; ch <= s->fbw_channels; ch++) {
00362         uint8_t *exp_strategy = s->exp_strategy[ch];
00363         uint8_t *exp          = s->blocks[0].exp[ch];
00364         int exp_diff;
00365 
00366         /* estimate if the exponent variation & decide if they should be
00367            reused in the next frame */
00368         exp_strategy[0] = EXP_NEW;
00369         exp += AC3_MAX_COEFS;
00370         for (blk = 1; blk < s->num_blocks; blk++, exp += AC3_MAX_COEFS) {
00371             if (ch == CPL_CH) {
00372                 if (!s->blocks[blk-1].cpl_in_use) {
00373                     exp_strategy[blk] = EXP_NEW;
00374                     continue;
00375                 } else if (!s->blocks[blk].cpl_in_use) {
00376                     exp_strategy[blk] = EXP_REUSE;
00377                     continue;
00378                 }
00379             } else if (s->blocks[blk].channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) {
00380                 exp_strategy[blk] = EXP_NEW;
00381                 continue;
00382             }
00383             exp_diff = s->dsp.sad[0](NULL, exp, exp - AC3_MAX_COEFS, 16, 16);
00384             exp_strategy[blk] = EXP_REUSE;
00385             if (ch == CPL_CH && exp_diff > (EXP_DIFF_THRESHOLD * (s->blocks[blk].end_freq[ch] - s->start_freq[ch]) / AC3_MAX_COEFS))
00386                 exp_strategy[blk] = EXP_NEW;
00387             else if (ch > CPL_CH && exp_diff > EXP_DIFF_THRESHOLD)
00388                 exp_strategy[blk] = EXP_NEW;
00389         }
00390 
00391         /* now select the encoding strategy type : if exponents are often
00392            recoded, we use a coarse encoding */
00393         blk = 0;
00394         while (blk < s->num_blocks) {
00395             blk1 = blk + 1;
00396             while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE)
00397                 blk1++;
00398             exp_strategy[blk] = exp_strategy_reuse_tab[s->num_blks_code][blk1-blk-1];
00399             blk = blk1;
00400         }
00401     }
00402     if (s->lfe_on) {
00403         ch = s->lfe_channel;
00404         s->exp_strategy[ch][0] = EXP_D15;
00405         for (blk = 1; blk < s->num_blocks; blk++)
00406             s->exp_strategy[ch][blk] = EXP_REUSE;
00407     }
00408 
00409     /* for E-AC-3, determine frame exponent strategy */
00410     if (CONFIG_EAC3_ENCODER && s->eac3)
00411         ff_eac3_get_frame_exp_strategy(s);
00412 }
00413 
00414 
00423 static void encode_exponents_blk_ch(uint8_t *exp, int nb_exps, int exp_strategy,
00424                                     int cpl)
00425 {
00426     int nb_groups, i, k;
00427 
00428     nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_exps] * 3;
00429 
00430     /* for each group, compute the minimum exponent */
00431     switch(exp_strategy) {
00432     case EXP_D25:
00433         for (i = 1, k = 1-cpl; i <= nb_groups; i++) {
00434             uint8_t exp_min = exp[k];
00435             if (exp[k+1] < exp_min)
00436                 exp_min = exp[k+1];
00437             exp[i-cpl] = exp_min;
00438             k += 2;
00439         }
00440         break;
00441     case EXP_D45:
00442         for (i = 1, k = 1-cpl; i <= nb_groups; i++) {
00443             uint8_t exp_min = exp[k];
00444             if (exp[k+1] < exp_min)
00445                 exp_min = exp[k+1];
00446             if (exp[k+2] < exp_min)
00447                 exp_min = exp[k+2];
00448             if (exp[k+3] < exp_min)
00449                 exp_min = exp[k+3];
00450             exp[i-cpl] = exp_min;
00451             k += 4;
00452         }
00453         break;
00454     }
00455 
00456     /* constraint for DC exponent */
00457     if (!cpl && exp[0] > 15)
00458         exp[0] = 15;
00459 
00460     /* decrease the delta between each groups to within 2 so that they can be
00461        differentially encoded */
00462     for (i = 1; i <= nb_groups; i++)
00463         exp[i] = FFMIN(exp[i], exp[i-1] + 2);
00464     i--;
00465     while (--i >= 0)
00466         exp[i] = FFMIN(exp[i], exp[i+1] + 2);
00467 
00468     if (cpl)
00469         exp[-1] = exp[0] & ~1;
00470 
00471     /* now we have the exponent values the decoder will see */
00472     switch (exp_strategy) {
00473     case EXP_D25:
00474         for (i = nb_groups, k = (nb_groups * 2)-cpl; i > 0; i--) {
00475             uint8_t exp1 = exp[i-cpl];
00476             exp[k--] = exp1;
00477             exp[k--] = exp1;
00478         }
00479         break;
00480     case EXP_D45:
00481         for (i = nb_groups, k = (nb_groups * 4)-cpl; i > 0; i--) {
00482             exp[k] = exp[k-1] = exp[k-2] = exp[k-3] = exp[i-cpl];
00483             k -= 4;
00484         }
00485         break;
00486     }
00487 }
00488 
00489 
00490 /*
00491  * Encode exponents from original extracted form to what the decoder will see.
00492  * This copies and groups exponents based on exponent strategy and reduces
00493  * deltas between adjacent exponent groups so that they can be differentially
00494  * encoded.
00495  */
00496 static void encode_exponents(AC3EncodeContext *s)
00497 {
00498     int blk, blk1, ch, cpl;
00499     uint8_t *exp, *exp_strategy;
00500     int nb_coefs, num_reuse_blocks;
00501 
00502     for (ch = !s->cpl_on; ch <= s->channels; ch++) {
00503         exp          = s->blocks[0].exp[ch] + s->start_freq[ch];
00504         exp_strategy = s->exp_strategy[ch];
00505 
00506         cpl = (ch == CPL_CH);
00507         blk = 0;
00508         while (blk < s->num_blocks) {
00509             AC3Block *block = &s->blocks[blk];
00510             if (cpl && !block->cpl_in_use) {
00511                 exp += AC3_MAX_COEFS;
00512                 blk++;
00513                 continue;
00514             }
00515             nb_coefs = block->end_freq[ch] - s->start_freq[ch];
00516             blk1 = blk + 1;
00517 
00518             /* count the number of EXP_REUSE blocks after the current block
00519                and set exponent reference block numbers */
00520             s->exp_ref_block[ch][blk] = blk;
00521             while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE) {
00522                 s->exp_ref_block[ch][blk1] = blk;
00523                 blk1++;
00524             }
00525             num_reuse_blocks = blk1 - blk - 1;
00526 
00527             /* for the EXP_REUSE case we select the min of the exponents */
00528             s->ac3dsp.ac3_exponent_min(exp-s->start_freq[ch], num_reuse_blocks,
00529                                        AC3_MAX_COEFS);
00530 
00531             encode_exponents_blk_ch(exp, nb_coefs, exp_strategy[blk], cpl);
00532 
00533             exp += AC3_MAX_COEFS * (num_reuse_blocks + 1);
00534             blk = blk1;
00535         }
00536     }
00537 
00538     /* reference block numbers have been changed, so reset ref_bap_set */
00539     s->ref_bap_set = 0;
00540 }
00541 
00542 
00543 /*
00544  * Count exponent bits based on bandwidth, coupling, and exponent strategies.
00545  */
00546 static int count_exponent_bits(AC3EncodeContext *s)
00547 {
00548     int blk, ch;
00549     int nb_groups, bit_count;
00550 
00551     bit_count = 0;
00552     for (blk = 0; blk < s->num_blocks; blk++) {
00553         AC3Block *block = &s->blocks[blk];
00554         for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
00555             int exp_strategy = s->exp_strategy[ch][blk];
00556             int cpl          = (ch == CPL_CH);
00557             int nb_coefs     = block->end_freq[ch] - s->start_freq[ch];
00558 
00559             if (exp_strategy == EXP_REUSE)
00560                 continue;
00561 
00562             nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_coefs];
00563             bit_count += 4 + (nb_groups * 7);
00564         }
00565     }
00566 
00567     return bit_count;
00568 }
00569 
00570 
00578 void ff_ac3_group_exponents(AC3EncodeContext *s)
00579 {
00580     int blk, ch, i, cpl;
00581     int group_size, nb_groups;
00582     uint8_t *p;
00583     int delta0, delta1, delta2;
00584     int exp0, exp1;
00585 
00586     for (blk = 0; blk < s->num_blocks; blk++) {
00587         AC3Block *block = &s->blocks[blk];
00588         for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
00589             int exp_strategy = s->exp_strategy[ch][blk];
00590             if (exp_strategy == EXP_REUSE)
00591                 continue;
00592             cpl = (ch == CPL_CH);
00593             group_size = exp_strategy + (exp_strategy == EXP_D45);
00594             nb_groups = exponent_group_tab[cpl][exp_strategy-1][block->end_freq[ch]-s->start_freq[ch]];
00595             p = block->exp[ch] + s->start_freq[ch] - cpl;
00596 
00597             /* DC exponent */
00598             exp1 = *p++;
00599             block->grouped_exp[ch][0] = exp1;
00600 
00601             /* remaining exponents are delta encoded */
00602             for (i = 1; i <= nb_groups; i++) {
00603                 /* merge three delta in one code */
00604                 exp0   = exp1;
00605                 exp1   = p[0];
00606                 p     += group_size;
00607                 delta0 = exp1 - exp0 + 2;
00608                 av_assert2(delta0 >= 0 && delta0 <= 4);
00609 
00610                 exp0   = exp1;
00611                 exp1   = p[0];
00612                 p     += group_size;
00613                 delta1 = exp1 - exp0 + 2;
00614                 av_assert2(delta1 >= 0 && delta1 <= 4);
00615 
00616                 exp0   = exp1;
00617                 exp1   = p[0];
00618                 p     += group_size;
00619                 delta2 = exp1 - exp0 + 2;
00620                 av_assert2(delta2 >= 0 && delta2 <= 4);
00621 
00622                 block->grouped_exp[ch][i] = ((delta0 * 5 + delta1) * 5) + delta2;
00623             }
00624         }
00625     }
00626 }
00627 
00628 
00636 void ff_ac3_process_exponents(AC3EncodeContext *s)
00637 {
00638     extract_exponents(s);
00639 
00640     compute_exp_strategy(s);
00641 
00642     encode_exponents(s);
00643 
00644     emms_c();
00645 }
00646 
00647 
00648 /*
00649  * Count frame bits that are based solely on fixed parameters.
00650  * This only has to be run once when the encoder is initialized.
00651  */
00652 static void count_frame_bits_fixed(AC3EncodeContext *s)
00653 {
00654     static const int frame_bits_inc[8] = { 0, 0, 2, 2, 2, 4, 2, 4 };
00655     int blk;
00656     int frame_bits;
00657 
00658     /* assumptions:
00659      *   no dynamic range codes
00660      *   bit allocation parameters do not change between blocks
00661      *   no delta bit allocation
00662      *   no skipped data
00663      *   no auxilliary data
00664      *   no E-AC-3 metadata
00665      */
00666 
00667     /* header */
00668     frame_bits = 16; /* sync info */
00669     if (s->eac3) {
00670         /* bitstream info header */
00671         frame_bits += 35;
00672         frame_bits += 1 + 1;
00673         if (s->num_blocks != 0x6)
00674             frame_bits++;
00675         frame_bits++;
00676         /* audio frame header */
00677         if (s->num_blocks == 6)
00678             frame_bits += 2;
00679         frame_bits += 10;
00680         /* exponent strategy */
00681         if (s->use_frame_exp_strategy)
00682             frame_bits += 5 * s->fbw_channels;
00683         else
00684             frame_bits += s->num_blocks * 2 * s->fbw_channels;
00685         if (s->lfe_on)
00686             frame_bits += s->num_blocks;
00687         /* converter exponent strategy */
00688         if (s->num_blks_code != 0x3)
00689             frame_bits++;
00690         else
00691             frame_bits += s->fbw_channels * 5;
00692         /* snr offsets */
00693         frame_bits += 10;
00694         /* block start info */
00695         if (s->num_blocks != 1)
00696             frame_bits++;
00697     } else {
00698         frame_bits += 49;
00699         frame_bits += frame_bits_inc[s->channel_mode];
00700     }
00701 
00702     /* audio blocks */
00703     for (blk = 0; blk < s->num_blocks; blk++) {
00704         if (!s->eac3) {
00705             /* block switch flags */
00706             frame_bits += s->fbw_channels;
00707 
00708             /* dither flags */
00709             frame_bits += s->fbw_channels;
00710         }
00711 
00712         /* dynamic range */
00713         frame_bits++;
00714 
00715         /* spectral extension */
00716         if (s->eac3)
00717             frame_bits++;
00718 
00719         if (!s->eac3) {
00720             /* exponent strategy */
00721             frame_bits += 2 * s->fbw_channels;
00722             if (s->lfe_on)
00723                 frame_bits++;
00724 
00725             /* bit allocation params */
00726             frame_bits++;
00727             if (!blk)
00728                 frame_bits += 2 + 2 + 2 + 2 + 3;
00729         }
00730 
00731         /* converter snr offset */
00732         if (s->eac3)
00733             frame_bits++;
00734 
00735         if (!s->eac3) {
00736             /* delta bit allocation */
00737             frame_bits++;
00738 
00739             /* skipped data */
00740             frame_bits++;
00741         }
00742     }
00743 
00744     /* auxiliary data */
00745     frame_bits++;
00746 
00747     /* CRC */
00748     frame_bits += 1 + 16;
00749 
00750     s->frame_bits_fixed = frame_bits;
00751 }
00752 
00753 
00754 /*
00755  * Initialize bit allocation.
00756  * Set default parameter codes and calculate parameter values.
00757  */
00758 static void bit_alloc_init(AC3EncodeContext *s)
00759 {
00760     int ch;
00761 
00762     /* init default parameters */
00763     s->slow_decay_code = 2;
00764     s->fast_decay_code = 1;
00765     s->slow_gain_code  = 1;
00766     s->db_per_bit_code = s->eac3 ? 2 : 3;
00767     s->floor_code      = 7;
00768     for (ch = 0; ch <= s->channels; ch++)
00769         s->fast_gain_code[ch] = 4;
00770 
00771     /* initial snr offset */
00772     s->coarse_snr_offset = 40;
00773 
00774     /* compute real values */
00775     /* currently none of these values change during encoding, so we can just
00776        set them once at initialization */
00777     s->bit_alloc.slow_decay = ff_ac3_slow_decay_tab[s->slow_decay_code] >> s->bit_alloc.sr_shift;
00778     s->bit_alloc.fast_decay = ff_ac3_fast_decay_tab[s->fast_decay_code] >> s->bit_alloc.sr_shift;
00779     s->bit_alloc.slow_gain  = ff_ac3_slow_gain_tab[s->slow_gain_code];
00780     s->bit_alloc.db_per_bit = ff_ac3_db_per_bit_tab[s->db_per_bit_code];
00781     s->bit_alloc.floor      = ff_ac3_floor_tab[s->floor_code];
00782     s->bit_alloc.cpl_fast_leak = 0;
00783     s->bit_alloc.cpl_slow_leak = 0;
00784 
00785     count_frame_bits_fixed(s);
00786 }
00787 
00788 
00789 /*
00790  * Count the bits used to encode the frame, minus exponents and mantissas.
00791  * Bits based on fixed parameters have already been counted, so now we just
00792  * have to add the bits based on parameters that change during encoding.
00793  */
00794 static void count_frame_bits(AC3EncodeContext *s)
00795 {
00796     AC3EncOptions *opt = &s->options;
00797     int blk, ch;
00798     int frame_bits = 0;
00799 
00800     /* header */
00801     if (s->eac3) {
00802         if (opt->eac3_mixing_metadata) {
00803             if (s->channel_mode > AC3_CHMODE_STEREO)
00804                 frame_bits += 2;
00805             if (s->has_center)
00806                 frame_bits += 6;
00807             if (s->has_surround)
00808                 frame_bits += 6;
00809             frame_bits += s->lfe_on;
00810             frame_bits += 1 + 1 + 2;
00811             if (s->channel_mode < AC3_CHMODE_STEREO)
00812                 frame_bits++;
00813             frame_bits++;
00814         }
00815         if (opt->eac3_info_metadata) {
00816             frame_bits += 3 + 1 + 1;
00817             if (s->channel_mode == AC3_CHMODE_STEREO)
00818                 frame_bits += 2 + 2;
00819             if (s->channel_mode >= AC3_CHMODE_2F2R)
00820                 frame_bits += 2;
00821             frame_bits++;
00822             if (opt->audio_production_info)
00823                 frame_bits += 5 + 2 + 1;
00824             frame_bits++;
00825         }
00826         /* coupling */
00827         if (s->channel_mode > AC3_CHMODE_MONO) {
00828             frame_bits++;
00829             for (blk = 1; blk < s->num_blocks; blk++) {
00830                 AC3Block *block = &s->blocks[blk];
00831                 frame_bits++;
00832                 if (block->new_cpl_strategy)
00833                     frame_bits++;
00834             }
00835         }
00836         /* coupling exponent strategy */
00837         if (s->cpl_on) {
00838             if (s->use_frame_exp_strategy) {
00839                 frame_bits += 5 * s->cpl_on;
00840             } else {
00841                 for (blk = 0; blk < s->num_blocks; blk++)
00842                     frame_bits += 2 * s->blocks[blk].cpl_in_use;
00843             }
00844         }
00845     } else {
00846         if (opt->audio_production_info)
00847             frame_bits += 7;
00848         if (s->bitstream_id == 6) {
00849             if (opt->extended_bsi_1)
00850                 frame_bits += 14;
00851             if (opt->extended_bsi_2)
00852                 frame_bits += 14;
00853         }
00854     }
00855 
00856     /* audio blocks */
00857     for (blk = 0; blk < s->num_blocks; blk++) {
00858         AC3Block *block = &s->blocks[blk];
00859 
00860         /* coupling strategy */
00861         if (!s->eac3)
00862             frame_bits++;
00863         if (block->new_cpl_strategy) {
00864             if (!s->eac3)
00865                 frame_bits++;
00866             if (block->cpl_in_use) {
00867                 if (s->eac3)
00868                     frame_bits++;
00869                 if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO)
00870                     frame_bits += s->fbw_channels;
00871                 if (s->channel_mode == AC3_CHMODE_STEREO)
00872                     frame_bits++;
00873                 frame_bits += 4 + 4;
00874                 if (s->eac3)
00875                     frame_bits++;
00876                 else
00877                     frame_bits += s->num_cpl_subbands - 1;
00878             }
00879         }
00880 
00881         /* coupling coordinates */
00882         if (block->cpl_in_use) {
00883             for (ch = 1; ch <= s->fbw_channels; ch++) {
00884                 if (block->channel_in_cpl[ch]) {
00885                     if (!s->eac3 || block->new_cpl_coords[ch] != 2)
00886                         frame_bits++;
00887                     if (block->new_cpl_coords[ch]) {
00888                         frame_bits += 2;
00889                         frame_bits += (4 + 4) * s->num_cpl_bands;
00890                     }
00891                 }
00892             }
00893         }
00894 
00895         /* stereo rematrixing */
00896         if (s->channel_mode == AC3_CHMODE_STEREO) {
00897             if (!s->eac3 || blk > 0)
00898                 frame_bits++;
00899             if (s->blocks[blk].new_rematrixing_strategy)
00900                 frame_bits += block->num_rematrixing_bands;
00901         }
00902 
00903         /* bandwidth codes & gain range */
00904         for (ch = 1; ch <= s->fbw_channels; ch++) {
00905             if (s->exp_strategy[ch][blk] != EXP_REUSE) {
00906                 if (!block->channel_in_cpl[ch])
00907                     frame_bits += 6;
00908                 frame_bits += 2;
00909             }
00910         }
00911 
00912         /* coupling exponent strategy */
00913         if (!s->eac3 && block->cpl_in_use)
00914             frame_bits += 2;
00915 
00916         /* snr offsets and fast gain codes */
00917         if (!s->eac3) {
00918             frame_bits++;
00919             if (block->new_snr_offsets)
00920                 frame_bits += 6 + (s->channels + block->cpl_in_use) * (4 + 3);
00921         }
00922 
00923         /* coupling leak info */
00924         if (block->cpl_in_use) {
00925             if (!s->eac3 || block->new_cpl_leak != 2)
00926                 frame_bits++;
00927             if (block->new_cpl_leak)
00928                 frame_bits += 3 + 3;
00929         }
00930     }
00931 
00932     s->frame_bits = s->frame_bits_fixed + frame_bits;
00933 }
00934 
00935 
00936 /*
00937  * Calculate masking curve based on the final exponents.
00938  * Also calculate the power spectral densities to use in future calculations.
00939  */
00940 static void bit_alloc_masking(AC3EncodeContext *s)
00941 {
00942     int blk, ch;
00943 
00944     for (blk = 0; blk < s->num_blocks; blk++) {
00945         AC3Block *block = &s->blocks[blk];
00946         for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
00947             /* We only need psd and mask for calculating bap.
00948                Since we currently do not calculate bap when exponent
00949                strategy is EXP_REUSE we do not need to calculate psd or mask. */
00950             if (s->exp_strategy[ch][blk] != EXP_REUSE) {
00951                 ff_ac3_bit_alloc_calc_psd(block->exp[ch], s->start_freq[ch],
00952                                           block->end_freq[ch], block->psd[ch],
00953                                           block->band_psd[ch]);
00954                 ff_ac3_bit_alloc_calc_mask(&s->bit_alloc, block->band_psd[ch],
00955                                            s->start_freq[ch], block->end_freq[ch],
00956                                            ff_ac3_fast_gain_tab[s->fast_gain_code[ch]],
00957                                            ch == s->lfe_channel,
00958                                            DBA_NONE, 0, NULL, NULL, NULL,
00959                                            block->mask[ch]);
00960             }
00961         }
00962     }
00963 }
00964 
00965 
00966 /*
00967  * Ensure that bap for each block and channel point to the current bap_buffer.
00968  * They may have been switched during the bit allocation search.
00969  */
00970 static void reset_block_bap(AC3EncodeContext *s)
00971 {
00972     int blk, ch;
00973     uint8_t *ref_bap;
00974 
00975     if (s->ref_bap[0][0] == s->bap_buffer && s->ref_bap_set)
00976         return;
00977 
00978     ref_bap = s->bap_buffer;
00979     for (ch = 0; ch <= s->channels; ch++) {
00980         for (blk = 0; blk < s->num_blocks; blk++)
00981             s->ref_bap[ch][blk] = ref_bap + AC3_MAX_COEFS * s->exp_ref_block[ch][blk];
00982         ref_bap += AC3_MAX_COEFS * s->num_blocks;
00983     }
00984     s->ref_bap_set = 1;
00985 }
00986 
00987 
00995 static void count_mantissa_bits_init(uint16_t mant_cnt[AC3_MAX_BLOCKS][16])
00996 {
00997     int blk;
00998 
00999     for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
01000         memset(mant_cnt[blk], 0, sizeof(mant_cnt[blk]));
01001         mant_cnt[blk][1] = mant_cnt[blk][2] = 2;
01002         mant_cnt[blk][4] = 1;
01003     }
01004 }
01005 
01006 
01017 static void count_mantissa_bits_update_ch(AC3EncodeContext *s, int ch,
01018                                           uint16_t mant_cnt[AC3_MAX_BLOCKS][16],
01019                                           int start, int end)
01020 {
01021     int blk;
01022 
01023     for (blk = 0; blk < s->num_blocks; blk++) {
01024         AC3Block *block = &s->blocks[blk];
01025         if (ch == CPL_CH && !block->cpl_in_use)
01026             continue;
01027         s->ac3dsp.update_bap_counts(mant_cnt[blk],
01028                                     s->ref_bap[ch][blk] + start,
01029                                     FFMIN(end, block->end_freq[ch]) - start);
01030     }
01031 }
01032 
01033 
01034 /*
01035  * Count the number of mantissa bits in the frame based on the bap values.
01036  */
01037 static int count_mantissa_bits(AC3EncodeContext *s)
01038 {
01039     int ch, max_end_freq;
01040     LOCAL_ALIGNED_16(uint16_t, mant_cnt, [AC3_MAX_BLOCKS], [16]);
01041 
01042     count_mantissa_bits_init(mant_cnt);
01043 
01044     max_end_freq = s->bandwidth_code * 3 + 73;
01045     for (ch = !s->cpl_enabled; ch <= s->channels; ch++)
01046         count_mantissa_bits_update_ch(s, ch, mant_cnt, s->start_freq[ch],
01047                                       max_end_freq);
01048 
01049     return s->ac3dsp.compute_mantissa_size(mant_cnt);
01050 }
01051 
01052 
01063 static int bit_alloc(AC3EncodeContext *s, int snr_offset)
01064 {
01065     int blk, ch;
01066 
01067     snr_offset = (snr_offset - 240) << 2;
01068 
01069     reset_block_bap(s);
01070     for (blk = 0; blk < s->num_blocks; blk++) {
01071         AC3Block *block = &s->blocks[blk];
01072 
01073         for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
01074             /* Currently the only bit allocation parameters which vary across
01075                blocks within a frame are the exponent values.  We can take
01076                advantage of that by reusing the bit allocation pointers
01077                whenever we reuse exponents. */
01078             if (s->exp_strategy[ch][blk] != EXP_REUSE) {
01079                 s->ac3dsp.bit_alloc_calc_bap(block->mask[ch], block->psd[ch],
01080                                              s->start_freq[ch], block->end_freq[ch],
01081                                              snr_offset, s->bit_alloc.floor,
01082                                              ff_ac3_bap_tab, s->ref_bap[ch][blk]);
01083             }
01084         }
01085     }
01086     return count_mantissa_bits(s);
01087 }
01088 
01089 
01090 /*
01091  * Constant bitrate bit allocation search.
01092  * Find the largest SNR offset that will allow data to fit in the frame.
01093  */
01094 static int cbr_bit_allocation(AC3EncodeContext *s)
01095 {
01096     int ch;
01097     int bits_left;
01098     int snr_offset, snr_incr;
01099 
01100     bits_left = 8 * s->frame_size - (s->frame_bits + s->exponent_bits);
01101     if (bits_left < 0)
01102         return AVERROR(EINVAL);
01103 
01104     snr_offset = s->coarse_snr_offset << 4;
01105 
01106     /* if previous frame SNR offset was 1023, check if current frame can also
01107        use SNR offset of 1023. if so, skip the search. */
01108     if ((snr_offset | s->fine_snr_offset[1]) == 1023) {
01109         if (bit_alloc(s, 1023) <= bits_left)
01110             return 0;
01111     }
01112 
01113     while (snr_offset >= 0 &&
01114            bit_alloc(s, snr_offset) > bits_left) {
01115         snr_offset -= 64;
01116     }
01117     if (snr_offset < 0)
01118         return AVERROR(EINVAL);
01119 
01120     FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
01121     for (snr_incr = 64; snr_incr > 0; snr_incr >>= 2) {
01122         while (snr_offset + snr_incr <= 1023 &&
01123                bit_alloc(s, snr_offset + snr_incr) <= bits_left) {
01124             snr_offset += snr_incr;
01125             FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
01126         }
01127     }
01128     FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
01129     reset_block_bap(s);
01130 
01131     s->coarse_snr_offset = snr_offset >> 4;
01132     for (ch = !s->cpl_on; ch <= s->channels; ch++)
01133         s->fine_snr_offset[ch] = snr_offset & 0xF;
01134 
01135     return 0;
01136 }
01137 
01138 
01139 /*
01140  * Perform bit allocation search.
01141  * Finds the SNR offset value that maximizes quality and fits in the specified
01142  * frame size.  Output is the SNR offset and a set of bit allocation pointers
01143  * used to quantize the mantissas.
01144  */
01145 int ff_ac3_compute_bit_allocation(AC3EncodeContext *s)
01146 {
01147     count_frame_bits(s);
01148 
01149     s->exponent_bits = count_exponent_bits(s);
01150 
01151     bit_alloc_masking(s);
01152 
01153     return cbr_bit_allocation(s);
01154 }
01155 
01156 
01165 static inline int sym_quant(int c, int e, int levels)
01166 {
01167     int v = (((levels * c) >> (24 - e)) + levels) >> 1;
01168     av_assert2(v >= 0 && v < levels);
01169     return v;
01170 }
01171 
01172 
01181 static inline int asym_quant(int c, int e, int qbits)
01182 {
01183     int m;
01184 
01185     c = (((c << e) >> (24 - qbits)) + 1) >> 1;
01186     m = (1 << (qbits-1));
01187     if (c >= m)
01188         c = m - 1;
01189     av_assert2(c >= -m);
01190     return c;
01191 }
01192 
01193 
01205 static void quantize_mantissas_blk_ch(AC3Mant *s, int32_t *fixed_coef,
01206                                       uint8_t *exp, uint8_t *bap,
01207                                       int16_t *qmant, int start_freq,
01208                                       int end_freq)
01209 {
01210     int i;
01211 
01212     for (i = start_freq; i < end_freq; i++) {
01213         int c = fixed_coef[i];
01214         int e = exp[i];
01215         int v = bap[i];
01216         if (v)
01217         switch (v) {
01218         case 1:
01219             v = sym_quant(c, e, 3);
01220             switch (s->mant1_cnt) {
01221             case 0:
01222                 s->qmant1_ptr = &qmant[i];
01223                 v = 9 * v;
01224                 s->mant1_cnt = 1;
01225                 break;
01226             case 1:
01227                 *s->qmant1_ptr += 3 * v;
01228                 s->mant1_cnt = 2;
01229                 v = 128;
01230                 break;
01231             default:
01232                 *s->qmant1_ptr += v;
01233                 s->mant1_cnt = 0;
01234                 v = 128;
01235                 break;
01236             }
01237             break;
01238         case 2:
01239             v = sym_quant(c, e, 5);
01240             switch (s->mant2_cnt) {
01241             case 0:
01242                 s->qmant2_ptr = &qmant[i];
01243                 v = 25 * v;
01244                 s->mant2_cnt = 1;
01245                 break;
01246             case 1:
01247                 *s->qmant2_ptr += 5 * v;
01248                 s->mant2_cnt = 2;
01249                 v = 128;
01250                 break;
01251             default:
01252                 *s->qmant2_ptr += v;
01253                 s->mant2_cnt = 0;
01254                 v = 128;
01255                 break;
01256             }
01257             break;
01258         case 3:
01259             v = sym_quant(c, e, 7);
01260             break;
01261         case 4:
01262             v = sym_quant(c, e, 11);
01263             switch (s->mant4_cnt) {
01264             case 0:
01265                 s->qmant4_ptr = &qmant[i];
01266                 v = 11 * v;
01267                 s->mant4_cnt = 1;
01268                 break;
01269             default:
01270                 *s->qmant4_ptr += v;
01271                 s->mant4_cnt = 0;
01272                 v = 128;
01273                 break;
01274             }
01275             break;
01276         case 5:
01277             v = sym_quant(c, e, 15);
01278             break;
01279         case 14:
01280             v = asym_quant(c, e, 14);
01281             break;
01282         case 15:
01283             v = asym_quant(c, e, 16);
01284             break;
01285         default:
01286             v = asym_quant(c, e, v - 1);
01287             break;
01288         }
01289         qmant[i] = v;
01290     }
01291 }
01292 
01293 
01299 void ff_ac3_quantize_mantissas(AC3EncodeContext *s)
01300 {
01301     int blk, ch, ch0=0, got_cpl;
01302 
01303     for (blk = 0; blk < s->num_blocks; blk++) {
01304         AC3Block *block = &s->blocks[blk];
01305         AC3Mant m = { 0 };
01306 
01307         got_cpl = !block->cpl_in_use;
01308         for (ch = 1; ch <= s->channels; ch++) {
01309             if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) {
01310                 ch0     = ch - 1;
01311                 ch      = CPL_CH;
01312                 got_cpl = 1;
01313             }
01314             quantize_mantissas_blk_ch(&m, block->fixed_coef[ch],
01315                                       s->blocks[s->exp_ref_block[ch][blk]].exp[ch],
01316                                       s->ref_bap[ch][blk], block->qmant[ch],
01317                                       s->start_freq[ch], block->end_freq[ch]);
01318             if (ch == CPL_CH)
01319                 ch = ch0;
01320         }
01321     }
01322 }
01323 
01324 
01325 /*
01326  * Write the AC-3 frame header to the output bitstream.
01327  */
01328 static void ac3_output_frame_header(AC3EncodeContext *s)
01329 {
01330     AC3EncOptions *opt = &s->options;
01331 
01332     put_bits(&s->pb, 16, 0x0b77);   /* frame header */
01333     put_bits(&s->pb, 16, 0);        /* crc1: will be filled later */
01334     put_bits(&s->pb, 2,  s->bit_alloc.sr_code);
01335     put_bits(&s->pb, 6,  s->frame_size_code + (s->frame_size - s->frame_size_min) / 2);
01336     put_bits(&s->pb, 5,  s->bitstream_id);
01337     put_bits(&s->pb, 3,  s->bitstream_mode);
01338     put_bits(&s->pb, 3,  s->channel_mode);
01339     if ((s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO)
01340         put_bits(&s->pb, 2, s->center_mix_level);
01341     if (s->channel_mode & 0x04)
01342         put_bits(&s->pb, 2, s->surround_mix_level);
01343     if (s->channel_mode == AC3_CHMODE_STEREO)
01344         put_bits(&s->pb, 2, opt->dolby_surround_mode);
01345     put_bits(&s->pb, 1, s->lfe_on); /* LFE */
01346     put_bits(&s->pb, 5, -opt->dialogue_level);
01347     put_bits(&s->pb, 1, 0);         /* no compression control word */
01348     put_bits(&s->pb, 1, 0);         /* no lang code */
01349     put_bits(&s->pb, 1, opt->audio_production_info);
01350     if (opt->audio_production_info) {
01351         put_bits(&s->pb, 5, opt->mixing_level - 80);
01352         put_bits(&s->pb, 2, opt->room_type);
01353     }
01354     put_bits(&s->pb, 1, opt->copyright);
01355     put_bits(&s->pb, 1, opt->original);
01356     if (s->bitstream_id == 6) {
01357         /* alternate bit stream syntax */
01358         put_bits(&s->pb, 1, opt->extended_bsi_1);
01359         if (opt->extended_bsi_1) {
01360             put_bits(&s->pb, 2, opt->preferred_stereo_downmix);
01361             put_bits(&s->pb, 3, s->ltrt_center_mix_level);
01362             put_bits(&s->pb, 3, s->ltrt_surround_mix_level);
01363             put_bits(&s->pb, 3, s->loro_center_mix_level);
01364             put_bits(&s->pb, 3, s->loro_surround_mix_level);
01365         }
01366         put_bits(&s->pb, 1, opt->extended_bsi_2);
01367         if (opt->extended_bsi_2) {
01368             put_bits(&s->pb, 2, opt->dolby_surround_ex_mode);
01369             put_bits(&s->pb, 2, opt->dolby_headphone_mode);
01370             put_bits(&s->pb, 1, opt->ad_converter_type);
01371             put_bits(&s->pb, 9, 0);     /* xbsi2 and encinfo : reserved */
01372         }
01373     } else {
01374     put_bits(&s->pb, 1, 0);         /* no time code 1 */
01375     put_bits(&s->pb, 1, 0);         /* no time code 2 */
01376     }
01377     put_bits(&s->pb, 1, 0);         /* no additional bit stream info */
01378 }
01379 
01380 
01381 /*
01382  * Write one audio block to the output bitstream.
01383  */
01384 static void output_audio_block(AC3EncodeContext *s, int blk)
01385 {
01386     int ch, i, baie, bnd, got_cpl;
01387     int av_uninit(ch0);
01388     AC3Block *block = &s->blocks[blk];
01389 
01390     /* block switching */
01391     if (!s->eac3) {
01392         for (ch = 0; ch < s->fbw_channels; ch++)
01393             put_bits(&s->pb, 1, 0);
01394     }
01395 
01396     /* dither flags */
01397     if (!s->eac3) {
01398         for (ch = 0; ch < s->fbw_channels; ch++)
01399             put_bits(&s->pb, 1, 1);
01400     }
01401 
01402     /* dynamic range codes */
01403     put_bits(&s->pb, 1, 0);
01404 
01405     /* spectral extension */
01406     if (s->eac3)
01407         put_bits(&s->pb, 1, 0);
01408 
01409     /* channel coupling */
01410     if (!s->eac3)
01411         put_bits(&s->pb, 1, block->new_cpl_strategy);
01412     if (block->new_cpl_strategy) {
01413         if (!s->eac3)
01414             put_bits(&s->pb, 1, block->cpl_in_use);
01415         if (block->cpl_in_use) {
01416             int start_sub, end_sub;
01417             if (s->eac3)
01418                 put_bits(&s->pb, 1, 0); /* enhanced coupling */
01419             if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO) {
01420                 for (ch = 1; ch <= s->fbw_channels; ch++)
01421                     put_bits(&s->pb, 1, block->channel_in_cpl[ch]);
01422             }
01423             if (s->channel_mode == AC3_CHMODE_STEREO)
01424                 put_bits(&s->pb, 1, 0); /* phase flags in use */
01425             start_sub = (s->start_freq[CPL_CH] - 37) / 12;
01426             end_sub   = (s->cpl_end_freq       - 37) / 12;
01427             put_bits(&s->pb, 4, start_sub);
01428             put_bits(&s->pb, 4, end_sub - 3);
01429             /* coupling band structure */
01430             if (s->eac3) {
01431                 put_bits(&s->pb, 1, 0); /* use default */
01432             } else {
01433                 for (bnd = start_sub+1; bnd < end_sub; bnd++)
01434                     put_bits(&s->pb, 1, ff_eac3_default_cpl_band_struct[bnd]);
01435             }
01436         }
01437     }
01438 
01439     /* coupling coordinates */
01440     if (block->cpl_in_use) {
01441         for (ch = 1; ch <= s->fbw_channels; ch++) {
01442             if (block->channel_in_cpl[ch]) {
01443                 if (!s->eac3 || block->new_cpl_coords[ch] != 2)
01444                     put_bits(&s->pb, 1, block->new_cpl_coords[ch]);
01445                 if (block->new_cpl_coords[ch]) {
01446                     put_bits(&s->pb, 2, block->cpl_master_exp[ch]);
01447                     for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
01448                         put_bits(&s->pb, 4, block->cpl_coord_exp [ch][bnd]);
01449                         put_bits(&s->pb, 4, block->cpl_coord_mant[ch][bnd]);
01450                     }
01451                 }
01452             }
01453         }
01454     }
01455 
01456     /* stereo rematrixing */
01457     if (s->channel_mode == AC3_CHMODE_STEREO) {
01458         if (!s->eac3 || blk > 0)
01459             put_bits(&s->pb, 1, block->new_rematrixing_strategy);
01460         if (block->new_rematrixing_strategy) {
01461             /* rematrixing flags */
01462             for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++)
01463                 put_bits(&s->pb, 1, block->rematrixing_flags[bnd]);
01464         }
01465     }
01466 
01467     /* exponent strategy */
01468     if (!s->eac3) {
01469         for (ch = !block->cpl_in_use; ch <= s->fbw_channels; ch++)
01470             put_bits(&s->pb, 2, s->exp_strategy[ch][blk]);
01471         if (s->lfe_on)
01472             put_bits(&s->pb, 1, s->exp_strategy[s->lfe_channel][blk]);
01473     }
01474 
01475     /* bandwidth */
01476     for (ch = 1; ch <= s->fbw_channels; ch++) {
01477         if (s->exp_strategy[ch][blk] != EXP_REUSE && !block->channel_in_cpl[ch])
01478             put_bits(&s->pb, 6, s->bandwidth_code);
01479     }
01480 
01481     /* exponents */
01482     for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
01483         int nb_groups;
01484         int cpl = (ch == CPL_CH);
01485 
01486         if (s->exp_strategy[ch][blk] == EXP_REUSE)
01487             continue;
01488 
01489         /* DC exponent */
01490         put_bits(&s->pb, 4, block->grouped_exp[ch][0] >> cpl);
01491 
01492         /* exponent groups */
01493         nb_groups = exponent_group_tab[cpl][s->exp_strategy[ch][blk]-1][block->end_freq[ch]-s->start_freq[ch]];
01494         for (i = 1; i <= nb_groups; i++)
01495             put_bits(&s->pb, 7, block->grouped_exp[ch][i]);
01496 
01497         /* gain range info */
01498         if (ch != s->lfe_channel && !cpl)
01499             put_bits(&s->pb, 2, 0);
01500     }
01501 
01502     /* bit allocation info */
01503     if (!s->eac3) {
01504         baie = (blk == 0);
01505         put_bits(&s->pb, 1, baie);
01506         if (baie) {
01507             put_bits(&s->pb, 2, s->slow_decay_code);
01508             put_bits(&s->pb, 2, s->fast_decay_code);
01509             put_bits(&s->pb, 2, s->slow_gain_code);
01510             put_bits(&s->pb, 2, s->db_per_bit_code);
01511             put_bits(&s->pb, 3, s->floor_code);
01512         }
01513     }
01514 
01515     /* snr offset */
01516     if (!s->eac3) {
01517         put_bits(&s->pb, 1, block->new_snr_offsets);
01518         if (block->new_snr_offsets) {
01519             put_bits(&s->pb, 6, s->coarse_snr_offset);
01520             for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
01521                 put_bits(&s->pb, 4, s->fine_snr_offset[ch]);
01522                 put_bits(&s->pb, 3, s->fast_gain_code[ch]);
01523             }
01524         }
01525     } else {
01526         put_bits(&s->pb, 1, 0); /* no converter snr offset */
01527     }
01528 
01529     /* coupling leak */
01530     if (block->cpl_in_use) {
01531         if (!s->eac3 || block->new_cpl_leak != 2)
01532             put_bits(&s->pb, 1, block->new_cpl_leak);
01533         if (block->new_cpl_leak) {
01534             put_bits(&s->pb, 3, s->bit_alloc.cpl_fast_leak);
01535             put_bits(&s->pb, 3, s->bit_alloc.cpl_slow_leak);
01536         }
01537     }
01538 
01539     if (!s->eac3) {
01540         put_bits(&s->pb, 1, 0); /* no delta bit allocation */
01541         put_bits(&s->pb, 1, 0); /* no data to skip */
01542     }
01543 
01544     /* mantissas */
01545     got_cpl = !block->cpl_in_use;
01546     for (ch = 1; ch <= s->channels; ch++) {
01547         int b, q;
01548 
01549         if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) {
01550             ch0     = ch - 1;
01551             ch      = CPL_CH;
01552             got_cpl = 1;
01553         }
01554         for (i = s->start_freq[ch]; i < block->end_freq[ch]; i++) {
01555             q = block->qmant[ch][i];
01556             b = s->ref_bap[ch][blk][i];
01557             switch (b) {
01558             case 0:                                          break;
01559             case 1: if (q != 128) put_bits (&s->pb,   5, q); break;
01560             case 2: if (q != 128) put_bits (&s->pb,   7, q); break;
01561             case 3:               put_sbits(&s->pb,   3, q); break;
01562             case 4: if (q != 128) put_bits (&s->pb,   7, q); break;
01563             case 14:              put_sbits(&s->pb,  14, q); break;
01564             case 15:              put_sbits(&s->pb,  16, q); break;
01565             default:              put_sbits(&s->pb, b-1, q); break;
01566             }
01567         }
01568         if (ch == CPL_CH)
01569             ch = ch0;
01570     }
01571 }
01572 
01573 
01575 #define CRC16_POLY ((1 << 0) | (1 << 2) | (1 << 15) | (1 << 16))
01576 
01577 
01578 static unsigned int mul_poly(unsigned int a, unsigned int b, unsigned int poly)
01579 {
01580     unsigned int c;
01581 
01582     c = 0;
01583     while (a) {
01584         if (a & 1)
01585             c ^= b;
01586         a = a >> 1;
01587         b = b << 1;
01588         if (b & (1 << 16))
01589             b ^= poly;
01590     }
01591     return c;
01592 }
01593 
01594 
01595 static unsigned int pow_poly(unsigned int a, unsigned int n, unsigned int poly)
01596 {
01597     unsigned int r;
01598     r = 1;
01599     while (n) {
01600         if (n & 1)
01601             r = mul_poly(r, a, poly);
01602         a = mul_poly(a, a, poly);
01603         n >>= 1;
01604     }
01605     return r;
01606 }
01607 
01608 
01609 /*
01610  * Fill the end of the frame with 0's and compute the two CRCs.
01611  */
01612 static void output_frame_end(AC3EncodeContext *s)
01613 {
01614     const AVCRC *crc_ctx = av_crc_get_table(AV_CRC_16_ANSI);
01615     int frame_size_58, pad_bytes, crc1, crc2_partial, crc2, crc_inv;
01616     uint8_t *frame;
01617 
01618     frame_size_58 = ((s->frame_size >> 2) + (s->frame_size >> 4)) << 1;
01619 
01620     /* pad the remainder of the frame with zeros */
01621     av_assert2(s->frame_size * 8 - put_bits_count(&s->pb) >= 18);
01622     flush_put_bits(&s->pb);
01623     frame = s->pb.buf;
01624     pad_bytes = s->frame_size - (put_bits_ptr(&s->pb) - frame) - 2;
01625     av_assert2(pad_bytes >= 0);
01626     if (pad_bytes > 0)
01627         memset(put_bits_ptr(&s->pb), 0, pad_bytes);
01628 
01629     if (s->eac3) {
01630         /* compute crc2 */
01631         crc2_partial = av_crc(crc_ctx, 0, frame + 2, s->frame_size - 5);
01632     } else {
01633     /* compute crc1 */
01634     /* this is not so easy because it is at the beginning of the data... */
01635     crc1    = av_bswap16(av_crc(crc_ctx, 0, frame + 4, frame_size_58 - 4));
01636     crc_inv = s->crc_inv[s->frame_size > s->frame_size_min];
01637     crc1    = mul_poly(crc_inv, crc1, CRC16_POLY);
01638     AV_WB16(frame + 2, crc1);
01639 
01640     /* compute crc2 */
01641     crc2_partial = av_crc(crc_ctx, 0, frame + frame_size_58,
01642                           s->frame_size - frame_size_58 - 3);
01643     }
01644     crc2 = av_crc(crc_ctx, crc2_partial, frame + s->frame_size - 3, 1);
01645     /* ensure crc2 does not match sync word by flipping crcrsv bit if needed */
01646     if (crc2 == 0x770B) {
01647         frame[s->frame_size - 3] ^= 0x1;
01648         crc2 = av_crc(crc_ctx, crc2_partial, frame + s->frame_size - 3, 1);
01649     }
01650     crc2 = av_bswap16(crc2);
01651     AV_WB16(frame + s->frame_size - 2, crc2);
01652 }
01653 
01654 
01661 void ff_ac3_output_frame(AC3EncodeContext *s, unsigned char *frame)
01662 {
01663     int blk;
01664 
01665     init_put_bits(&s->pb, frame, AC3_MAX_CODED_FRAME_SIZE);
01666 
01667     s->output_frame_header(s);
01668 
01669     for (blk = 0; blk < s->num_blocks; blk++)
01670         output_audio_block(s, blk);
01671 
01672     output_frame_end(s);
01673 }
01674 
01675 
01676 static void dprint_options(AC3EncodeContext *s)
01677 {
01678 #ifdef DEBUG
01679     AVCodecContext *avctx = s->avctx;
01680     AC3EncOptions *opt = &s->options;
01681     char strbuf[32];
01682 
01683     switch (s->bitstream_id) {
01684     case  6:  av_strlcpy(strbuf, "AC-3 (alt syntax)",       32); break;
01685     case  8:  av_strlcpy(strbuf, "AC-3 (standard)",         32); break;
01686     case  9:  av_strlcpy(strbuf, "AC-3 (dnet half-rate)",   32); break;
01687     case 10:  av_strlcpy(strbuf, "AC-3 (dnet quater-rate)", 32); break;
01688     case 16:  av_strlcpy(strbuf, "E-AC-3 (enhanced)",       32); break;
01689     default: snprintf(strbuf, 32, "ERROR");
01690     }
01691     av_dlog(avctx, "bitstream_id: %s (%d)\n", strbuf, s->bitstream_id);
01692     av_dlog(avctx, "sample_fmt: %s\n", av_get_sample_fmt_name(avctx->sample_fmt));
01693     av_get_channel_layout_string(strbuf, 32, s->channels, avctx->channel_layout);
01694     av_dlog(avctx, "channel_layout: %s\n", strbuf);
01695     av_dlog(avctx, "sample_rate: %d\n", s->sample_rate);
01696     av_dlog(avctx, "bit_rate: %d\n", s->bit_rate);
01697     av_dlog(avctx, "blocks/frame: %d (code=%d)\n", s->num_blocks, s->num_blks_code);
01698     if (s->cutoff)
01699         av_dlog(avctx, "cutoff: %d\n", s->cutoff);
01700 
01701     av_dlog(avctx, "per_frame_metadata: %s\n",
01702             opt->allow_per_frame_metadata?"on":"off");
01703     if (s->has_center)
01704         av_dlog(avctx, "center_mixlev: %0.3f (%d)\n", opt->center_mix_level,
01705                 s->center_mix_level);
01706     else
01707         av_dlog(avctx, "center_mixlev: {not written}\n");
01708     if (s->has_surround)
01709         av_dlog(avctx, "surround_mixlev: %0.3f (%d)\n", opt->surround_mix_level,
01710                 s->surround_mix_level);
01711     else
01712         av_dlog(avctx, "surround_mixlev: {not written}\n");
01713     if (opt->audio_production_info) {
01714         av_dlog(avctx, "mixing_level: %ddB\n", opt->mixing_level);
01715         switch (opt->room_type) {
01716         case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
01717         case AC3ENC_OPT_LARGE_ROOM:    av_strlcpy(strbuf, "large", 32);        break;
01718         case AC3ENC_OPT_SMALL_ROOM:    av_strlcpy(strbuf, "small", 32);        break;
01719         default: snprintf(strbuf, 32, "ERROR (%d)", opt->room_type);
01720         }
01721         av_dlog(avctx, "room_type: %s\n", strbuf);
01722     } else {
01723         av_dlog(avctx, "mixing_level: {not written}\n");
01724         av_dlog(avctx, "room_type: {not written}\n");
01725     }
01726     av_dlog(avctx, "copyright: %s\n", opt->copyright?"on":"off");
01727     av_dlog(avctx, "dialnorm: %ddB\n", opt->dialogue_level);
01728     if (s->channel_mode == AC3_CHMODE_STEREO) {
01729         switch (opt->dolby_surround_mode) {
01730         case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
01731         case AC3ENC_OPT_MODE_ON:       av_strlcpy(strbuf, "on", 32);           break;
01732         case AC3ENC_OPT_MODE_OFF:      av_strlcpy(strbuf, "off", 32);          break;
01733         default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_surround_mode);
01734         }
01735         av_dlog(avctx, "dsur_mode: %s\n", strbuf);
01736     } else {
01737         av_dlog(avctx, "dsur_mode: {not written}\n");
01738     }
01739     av_dlog(avctx, "original: %s\n", opt->original?"on":"off");
01740 
01741     if (s->bitstream_id == 6) {
01742         if (opt->extended_bsi_1) {
01743             switch (opt->preferred_stereo_downmix) {
01744             case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
01745             case AC3ENC_OPT_DOWNMIX_LTRT:  av_strlcpy(strbuf, "ltrt", 32);         break;
01746             case AC3ENC_OPT_DOWNMIX_LORO:  av_strlcpy(strbuf, "loro", 32);         break;
01747             default: snprintf(strbuf, 32, "ERROR (%d)", opt->preferred_stereo_downmix);
01748             }
01749             av_dlog(avctx, "dmix_mode: %s\n", strbuf);
01750             av_dlog(avctx, "ltrt_cmixlev: %0.3f (%d)\n",
01751                     opt->ltrt_center_mix_level, s->ltrt_center_mix_level);
01752             av_dlog(avctx, "ltrt_surmixlev: %0.3f (%d)\n",
01753                     opt->ltrt_surround_mix_level, s->ltrt_surround_mix_level);
01754             av_dlog(avctx, "loro_cmixlev: %0.3f (%d)\n",
01755                     opt->loro_center_mix_level, s->loro_center_mix_level);
01756             av_dlog(avctx, "loro_surmixlev: %0.3f (%d)\n",
01757                     opt->loro_surround_mix_level, s->loro_surround_mix_level);
01758         } else {
01759             av_dlog(avctx, "extended bitstream info 1: {not written}\n");
01760         }
01761         if (opt->extended_bsi_2) {
01762             switch (opt->dolby_surround_ex_mode) {
01763             case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
01764             case AC3ENC_OPT_MODE_ON:       av_strlcpy(strbuf, "on", 32);           break;
01765             case AC3ENC_OPT_MODE_OFF:      av_strlcpy(strbuf, "off", 32);          break;
01766             default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_surround_ex_mode);
01767             }
01768             av_dlog(avctx, "dsurex_mode: %s\n", strbuf);
01769             switch (opt->dolby_headphone_mode) {
01770             case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
01771             case AC3ENC_OPT_MODE_ON:       av_strlcpy(strbuf, "on", 32);           break;
01772             case AC3ENC_OPT_MODE_OFF:      av_strlcpy(strbuf, "off", 32);          break;
01773             default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_headphone_mode);
01774             }
01775             av_dlog(avctx, "dheadphone_mode: %s\n", strbuf);
01776 
01777             switch (opt->ad_converter_type) {
01778             case AC3ENC_OPT_ADCONV_STANDARD: av_strlcpy(strbuf, "standard", 32); break;
01779             case AC3ENC_OPT_ADCONV_HDCD:     av_strlcpy(strbuf, "hdcd", 32);     break;
01780             default: snprintf(strbuf, 32, "ERROR (%d)", opt->ad_converter_type);
01781             }
01782             av_dlog(avctx, "ad_conv_type: %s\n", strbuf);
01783         } else {
01784             av_dlog(avctx, "extended bitstream info 2: {not written}\n");
01785         }
01786     }
01787 #endif
01788 }
01789 
01790 
01791 #define FLT_OPTION_THRESHOLD 0.01
01792 
01793 static int validate_float_option(float v, const float *v_list, int v_list_size)
01794 {
01795     int i;
01796 
01797     for (i = 0; i < v_list_size; i++) {
01798         if (v < (v_list[i] + FLT_OPTION_THRESHOLD) &&
01799             v > (v_list[i] - FLT_OPTION_THRESHOLD))
01800             break;
01801     }
01802     if (i == v_list_size)
01803         return -1;
01804 
01805     return i;
01806 }
01807 
01808 
01809 static void validate_mix_level(void *log_ctx, const char *opt_name,
01810                                float *opt_param, const float *list,
01811                                int list_size, int default_value, int min_value,
01812                                int *ctx_param)
01813 {
01814     int mixlev = validate_float_option(*opt_param, list, list_size);
01815     if (mixlev < min_value) {
01816         mixlev = default_value;
01817         if (*opt_param >= 0.0) {
01818             av_log(log_ctx, AV_LOG_WARNING, "requested %s is not valid. using "
01819                    "default value: %0.3f\n", opt_name, list[mixlev]);
01820         }
01821     }
01822     *opt_param = list[mixlev];
01823     *ctx_param = mixlev;
01824 }
01825 
01826 
01833 int ff_ac3_validate_metadata(AC3EncodeContext *s)
01834 {
01835     AVCodecContext *avctx = s->avctx;
01836     AC3EncOptions *opt = &s->options;
01837 
01838     opt->audio_production_info = 0;
01839     opt->extended_bsi_1        = 0;
01840     opt->extended_bsi_2        = 0;
01841     opt->eac3_mixing_metadata  = 0;
01842     opt->eac3_info_metadata    = 0;
01843 
01844     /* determine mixing metadata / xbsi1 use */
01845     if (s->channel_mode > AC3_CHMODE_STEREO && opt->preferred_stereo_downmix != AC3ENC_OPT_NONE) {
01846         opt->extended_bsi_1       = 1;
01847         opt->eac3_mixing_metadata = 1;
01848     }
01849     if (s->has_center &&
01850         (opt->ltrt_center_mix_level >= 0 || opt->loro_center_mix_level >= 0)) {
01851         opt->extended_bsi_1       = 1;
01852         opt->eac3_mixing_metadata = 1;
01853     }
01854     if (s->has_surround &&
01855         (opt->ltrt_surround_mix_level >= 0 || opt->loro_surround_mix_level >= 0)) {
01856         opt->extended_bsi_1       = 1;
01857         opt->eac3_mixing_metadata = 1;
01858     }
01859 
01860     if (s->eac3) {
01861         /* determine info metadata use */
01862         if (avctx->audio_service_type != AV_AUDIO_SERVICE_TYPE_MAIN)
01863             opt->eac3_info_metadata = 1;
01864         if (opt->copyright != AC3ENC_OPT_NONE || opt->original != AC3ENC_OPT_NONE)
01865             opt->eac3_info_metadata = 1;
01866         if (s->channel_mode == AC3_CHMODE_STEREO &&
01867             (opt->dolby_headphone_mode != AC3ENC_OPT_NONE || opt->dolby_surround_mode != AC3ENC_OPT_NONE))
01868             opt->eac3_info_metadata = 1;
01869         if (s->channel_mode >= AC3_CHMODE_2F2R && opt->dolby_surround_ex_mode != AC3ENC_OPT_NONE)
01870             opt->eac3_info_metadata = 1;
01871         if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE ||
01872             opt->ad_converter_type != AC3ENC_OPT_NONE) {
01873             opt->audio_production_info = 1;
01874             opt->eac3_info_metadata    = 1;
01875         }
01876     } else {
01877         /* determine audio production info use */
01878         if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE)
01879             opt->audio_production_info = 1;
01880 
01881         /* determine xbsi2 use */
01882         if (s->channel_mode >= AC3_CHMODE_2F2R && opt->dolby_surround_ex_mode != AC3ENC_OPT_NONE)
01883             opt->extended_bsi_2 = 1;
01884         if (s->channel_mode == AC3_CHMODE_STEREO && opt->dolby_headphone_mode != AC3ENC_OPT_NONE)
01885             opt->extended_bsi_2 = 1;
01886         if (opt->ad_converter_type != AC3ENC_OPT_NONE)
01887             opt->extended_bsi_2 = 1;
01888     }
01889 
01890     /* validate AC-3 mixing levels */
01891     if (!s->eac3) {
01892         if (s->has_center) {
01893             validate_mix_level(avctx, "center_mix_level", &opt->center_mix_level,
01894                             cmixlev_options, CMIXLEV_NUM_OPTIONS, 1, 0,
01895                             &s->center_mix_level);
01896         }
01897         if (s->has_surround) {
01898             validate_mix_level(avctx, "surround_mix_level", &opt->surround_mix_level,
01899                             surmixlev_options, SURMIXLEV_NUM_OPTIONS, 1, 0,
01900                             &s->surround_mix_level);
01901         }
01902     }
01903 
01904     /* validate extended bsi 1 / mixing metadata */
01905     if (opt->extended_bsi_1 || opt->eac3_mixing_metadata) {
01906         /* default preferred stereo downmix */
01907         if (opt->preferred_stereo_downmix == AC3ENC_OPT_NONE)
01908             opt->preferred_stereo_downmix = AC3ENC_OPT_NOT_INDICATED;
01909         if (!s->eac3 || s->has_center) {
01910             /* validate Lt/Rt center mix level */
01911             validate_mix_level(avctx, "ltrt_center_mix_level",
01912                                &opt->ltrt_center_mix_level, extmixlev_options,
01913                                EXTMIXLEV_NUM_OPTIONS, 5, 0,
01914                                &s->ltrt_center_mix_level);
01915             /* validate Lo/Ro center mix level */
01916             validate_mix_level(avctx, "loro_center_mix_level",
01917                                &opt->loro_center_mix_level, extmixlev_options,
01918                                EXTMIXLEV_NUM_OPTIONS, 5, 0,
01919                                &s->loro_center_mix_level);
01920         }
01921         if (!s->eac3 || s->has_surround) {
01922             /* validate Lt/Rt surround mix level */
01923             validate_mix_level(avctx, "ltrt_surround_mix_level",
01924                                &opt->ltrt_surround_mix_level, extmixlev_options,
01925                                EXTMIXLEV_NUM_OPTIONS, 6, 3,
01926                                &s->ltrt_surround_mix_level);
01927             /* validate Lo/Ro surround mix level */
01928             validate_mix_level(avctx, "loro_surround_mix_level",
01929                                &opt->loro_surround_mix_level, extmixlev_options,
01930                                EXTMIXLEV_NUM_OPTIONS, 6, 3,
01931                                &s->loro_surround_mix_level);
01932         }
01933     }
01934 
01935     /* validate audio service type / channels combination */
01936     if ((avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_KARAOKE &&
01937          avctx->channels == 1) ||
01938         ((avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_COMMENTARY ||
01939           avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_EMERGENCY  ||
01940           avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_VOICE_OVER)
01941          && avctx->channels > 1)) {
01942         av_log(avctx, AV_LOG_ERROR, "invalid audio service type for the "
01943                                     "specified number of channels\n");
01944         return AVERROR(EINVAL);
01945     }
01946 
01947     /* validate extended bsi 2 / info metadata */
01948     if (opt->extended_bsi_2 || opt->eac3_info_metadata) {
01949         /* default dolby headphone mode */
01950         if (opt->dolby_headphone_mode == AC3ENC_OPT_NONE)
01951             opt->dolby_headphone_mode = AC3ENC_OPT_NOT_INDICATED;
01952         /* default dolby surround ex mode */
01953         if (opt->dolby_surround_ex_mode == AC3ENC_OPT_NONE)
01954             opt->dolby_surround_ex_mode = AC3ENC_OPT_NOT_INDICATED;
01955         /* default A/D converter type */
01956         if (opt->ad_converter_type == AC3ENC_OPT_NONE)
01957             opt->ad_converter_type = AC3ENC_OPT_ADCONV_STANDARD;
01958     }
01959 
01960     /* copyright & original defaults */
01961     if (!s->eac3 || opt->eac3_info_metadata) {
01962         /* default copyright */
01963         if (opt->copyright == AC3ENC_OPT_NONE)
01964             opt->copyright = AC3ENC_OPT_OFF;
01965         /* default original */
01966         if (opt->original == AC3ENC_OPT_NONE)
01967             opt->original = AC3ENC_OPT_ON;
01968     }
01969 
01970     /* dolby surround mode default */
01971     if (!s->eac3 || opt->eac3_info_metadata) {
01972         if (opt->dolby_surround_mode == AC3ENC_OPT_NONE)
01973             opt->dolby_surround_mode = AC3ENC_OPT_NOT_INDICATED;
01974     }
01975 
01976     /* validate audio production info */
01977     if (opt->audio_production_info) {
01978         if (opt->mixing_level == AC3ENC_OPT_NONE) {
01979             av_log(avctx, AV_LOG_ERROR, "mixing_level must be set if "
01980                    "room_type is set\n");
01981             return AVERROR(EINVAL);
01982         }
01983         if (opt->mixing_level < 80) {
01984             av_log(avctx, AV_LOG_ERROR, "invalid mixing level. must be between "
01985                    "80dB and 111dB\n");
01986             return AVERROR(EINVAL);
01987         }
01988         /* default room type */
01989         if (opt->room_type == AC3ENC_OPT_NONE)
01990             opt->room_type = AC3ENC_OPT_NOT_INDICATED;
01991     }
01992 
01993     /* set bitstream id for alternate bitstream syntax */
01994     if (!s->eac3 && (opt->extended_bsi_1 || opt->extended_bsi_2)) {
01995         if (s->bitstream_id > 8 && s->bitstream_id < 11) {
01996             static int warn_once = 1;
01997             if (warn_once) {
01998                 av_log(avctx, AV_LOG_WARNING, "alternate bitstream syntax is "
01999                        "not compatible with reduced samplerates. writing of "
02000                        "extended bitstream information will be disabled.\n");
02001                 warn_once = 0;
02002             }
02003         } else {
02004             s->bitstream_id = 6;
02005         }
02006     }
02007 
02008     return 0;
02009 }
02010 
02011 
02017 av_cold int ff_ac3_encode_close(AVCodecContext *avctx)
02018 {
02019     int blk, ch;
02020     AC3EncodeContext *s = avctx->priv_data;
02021 
02022     av_freep(&s->windowed_samples);
02023     for (ch = 0; ch < s->channels; ch++)
02024         av_freep(&s->planar_samples[ch]);
02025     av_freep(&s->planar_samples);
02026     av_freep(&s->bap_buffer);
02027     av_freep(&s->bap1_buffer);
02028     av_freep(&s->mdct_coef_buffer);
02029     av_freep(&s->fixed_coef_buffer);
02030     av_freep(&s->exp_buffer);
02031     av_freep(&s->grouped_exp_buffer);
02032     av_freep(&s->psd_buffer);
02033     av_freep(&s->band_psd_buffer);
02034     av_freep(&s->mask_buffer);
02035     av_freep(&s->qmant_buffer);
02036     av_freep(&s->cpl_coord_exp_buffer);
02037     av_freep(&s->cpl_coord_mant_buffer);
02038     for (blk = 0; blk < s->num_blocks; blk++) {
02039         AC3Block *block = &s->blocks[blk];
02040         av_freep(&block->mdct_coef);
02041         av_freep(&block->fixed_coef);
02042         av_freep(&block->exp);
02043         av_freep(&block->grouped_exp);
02044         av_freep(&block->psd);
02045         av_freep(&block->band_psd);
02046         av_freep(&block->mask);
02047         av_freep(&block->qmant);
02048         av_freep(&block->cpl_coord_exp);
02049         av_freep(&block->cpl_coord_mant);
02050     }
02051 
02052     s->mdct_end(s);
02053 
02054     av_freep(&avctx->coded_frame);
02055     return 0;
02056 }
02057 
02058 
02059 /*
02060  * Set channel information during initialization.
02061  */
02062 static av_cold int set_channel_info(AC3EncodeContext *s, int channels,
02063                                     uint64_t *channel_layout)
02064 {
02065     int ch_layout;
02066 
02067     if (channels < 1 || channels > AC3_MAX_CHANNELS)
02068         return AVERROR(EINVAL);
02069     if (*channel_layout > 0x7FF)
02070         return AVERROR(EINVAL);
02071     ch_layout = *channel_layout;
02072     if (!ch_layout)
02073         ch_layout = avcodec_guess_channel_layout(channels, CODEC_ID_AC3, NULL);
02074 
02075     s->lfe_on       = !!(ch_layout & AV_CH_LOW_FREQUENCY);
02076     s->channels     = channels;
02077     s->fbw_channels = channels - s->lfe_on;
02078     s->lfe_channel  = s->lfe_on ? s->fbw_channels + 1 : -1;
02079     if (s->lfe_on)
02080         ch_layout -= AV_CH_LOW_FREQUENCY;
02081 
02082     switch (ch_layout) {
02083     case AV_CH_LAYOUT_MONO:           s->channel_mode = AC3_CHMODE_MONO;   break;
02084     case AV_CH_LAYOUT_STEREO:         s->channel_mode = AC3_CHMODE_STEREO; break;
02085     case AV_CH_LAYOUT_SURROUND:       s->channel_mode = AC3_CHMODE_3F;     break;
02086     case AV_CH_LAYOUT_2_1:            s->channel_mode = AC3_CHMODE_2F1R;   break;
02087     case AV_CH_LAYOUT_4POINT0:        s->channel_mode = AC3_CHMODE_3F1R;   break;
02088     case AV_CH_LAYOUT_QUAD:
02089     case AV_CH_LAYOUT_2_2:            s->channel_mode = AC3_CHMODE_2F2R;   break;
02090     case AV_CH_LAYOUT_5POINT0:
02091     case AV_CH_LAYOUT_5POINT0_BACK:   s->channel_mode = AC3_CHMODE_3F2R;   break;
02092     default:
02093         return AVERROR(EINVAL);
02094     }
02095     s->has_center   = (s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO;
02096     s->has_surround =  s->channel_mode & 0x04;
02097 
02098     s->channel_map  = ff_ac3_enc_channel_map[s->channel_mode][s->lfe_on];
02099     *channel_layout = ch_layout;
02100     if (s->lfe_on)
02101         *channel_layout |= AV_CH_LOW_FREQUENCY;
02102 
02103     return 0;
02104 }
02105 
02106 
02107 static av_cold int validate_options(AC3EncodeContext *s)
02108 {
02109     AVCodecContext *avctx = s->avctx;
02110     int i, ret, max_sr;
02111 
02112     /* validate channel layout */
02113     if (!avctx->channel_layout) {
02114         av_log(avctx, AV_LOG_WARNING, "No channel layout specified. The "
02115                                       "encoder will guess the layout, but it "
02116                                       "might be incorrect.\n");
02117     }
02118     ret = set_channel_info(s, avctx->channels, &avctx->channel_layout);
02119     if (ret) {
02120         av_log(avctx, AV_LOG_ERROR, "invalid channel layout\n");
02121         return ret;
02122     }
02123 
02124     /* validate sample rate */
02125     /* note: max_sr could be changed from 2 to 5 for E-AC-3 once we find a
02126              decoder that supports half sample rate so we can validate that
02127              the generated files are correct. */
02128     max_sr = s->eac3 ? 2 : 8;
02129     for (i = 0; i <= max_sr; i++) {
02130         if ((ff_ac3_sample_rate_tab[i % 3] >> (i / 3)) == avctx->sample_rate)
02131             break;
02132     }
02133     if (i > max_sr) {
02134         av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n");
02135         return AVERROR(EINVAL);
02136     }
02137     s->sample_rate        = avctx->sample_rate;
02138     s->bit_alloc.sr_shift = i / 3;
02139     s->bit_alloc.sr_code  = i % 3;
02140     s->bitstream_id       = s->eac3 ? 16 : 8 + s->bit_alloc.sr_shift;
02141 
02142     /* validate bit rate */
02143     if (s->eac3) {
02144         int max_br, min_br, wpf, min_br_dist, min_br_code;
02145         int num_blks_code, num_blocks, frame_samples;
02146 
02147         /* calculate min/max bitrate */
02148         /* TODO: More testing with 3 and 2 blocks. All E-AC-3 samples I've
02149                  found use either 6 blocks or 1 block, even though 2 or 3 blocks
02150                  would work as far as the bit rate is concerned. */
02151         for (num_blks_code = 3; num_blks_code >= 0; num_blks_code--) {
02152             num_blocks = ((int[]){ 1, 2, 3, 6 })[num_blks_code];
02153             frame_samples  = AC3_BLOCK_SIZE * num_blocks;
02154             max_br = 2048 * s->sample_rate / frame_samples * 16;
02155             min_br = ((s->sample_rate + (frame_samples-1)) / frame_samples) * 16;
02156             if (avctx->bit_rate <= max_br)
02157                 break;
02158         }
02159         if (avctx->bit_rate < min_br || avctx->bit_rate > max_br) {
02160             av_log(avctx, AV_LOG_ERROR, "invalid bit rate. must be %d to %d "
02161                    "for this sample rate\n", min_br, max_br);
02162             return AVERROR(EINVAL);
02163         }
02164         s->num_blks_code = num_blks_code;
02165         s->num_blocks    = num_blocks;
02166 
02167         /* calculate words-per-frame for the selected bitrate */
02168         wpf = (avctx->bit_rate / 16) * frame_samples / s->sample_rate;
02169         av_assert1(wpf > 0 && wpf <= 2048);
02170 
02171         /* find the closest AC-3 bitrate code to the selected bitrate.
02172            this is needed for lookup tables for bandwidth and coupling
02173            parameter selection */
02174         min_br_code = -1;
02175         min_br_dist = INT_MAX;
02176         for (i = 0; i < 19; i++) {
02177             int br_dist = abs(ff_ac3_bitrate_tab[i] * 1000 - avctx->bit_rate);
02178             if (br_dist < min_br_dist) {
02179                 min_br_dist = br_dist;
02180                 min_br_code = i;
02181             }
02182         }
02183 
02184         /* make sure the minimum frame size is below the average frame size */
02185         s->frame_size_code = min_br_code << 1;
02186         while (wpf > 1 && wpf * s->sample_rate / AC3_FRAME_SIZE * 16 > avctx->bit_rate)
02187             wpf--;
02188         s->frame_size_min = 2 * wpf;
02189     } else {
02190         for (i = 0; i < 19; i++) {
02191             if ((ff_ac3_bitrate_tab[i] >> s->bit_alloc.sr_shift)*1000 == avctx->bit_rate)
02192                 break;
02193         }
02194         if (i == 19) {
02195             av_log(avctx, AV_LOG_ERROR, "invalid bit rate\n");
02196             return AVERROR(EINVAL);
02197         }
02198         s->frame_size_code = i << 1;
02199         s->frame_size_min  = 2 * ff_ac3_frame_size_tab[s->frame_size_code][s->bit_alloc.sr_code];
02200         s->num_blks_code   = 0x3;
02201         s->num_blocks      = 6;
02202     }
02203     s->bit_rate   = avctx->bit_rate;
02204     s->frame_size = s->frame_size_min;
02205 
02206     /* validate cutoff */
02207     if (avctx->cutoff < 0) {
02208         av_log(avctx, AV_LOG_ERROR, "invalid cutoff frequency\n");
02209         return AVERROR(EINVAL);
02210     }
02211     s->cutoff = avctx->cutoff;
02212     if (s->cutoff > (s->sample_rate >> 1))
02213         s->cutoff = s->sample_rate >> 1;
02214 
02215     ret = ff_ac3_validate_metadata(s);
02216     if (ret)
02217         return ret;
02218 
02219     s->rematrixing_enabled = s->options.stereo_rematrixing &&
02220                              (s->channel_mode == AC3_CHMODE_STEREO);
02221 
02222     s->cpl_enabled = s->options.channel_coupling &&
02223                      s->channel_mode >= AC3_CHMODE_STEREO;
02224 
02225     return 0;
02226 }
02227 
02228 
02229 /*
02230  * Set bandwidth for all channels.
02231  * The user can optionally supply a cutoff frequency. Otherwise an appropriate
02232  * default value will be used.
02233  */
02234 static av_cold void set_bandwidth(AC3EncodeContext *s)
02235 {
02236     int blk, ch;
02237     int av_uninit(cpl_start);
02238 
02239     if (s->cutoff) {
02240         /* calculate bandwidth based on user-specified cutoff frequency */
02241         int fbw_coeffs;
02242         fbw_coeffs     = s->cutoff * 2 * AC3_MAX_COEFS / s->sample_rate;
02243         s->bandwidth_code = av_clip((fbw_coeffs - 73) / 3, 0, 60);
02244     } else {
02245         /* use default bandwidth setting */
02246         s->bandwidth_code = ac3_bandwidth_tab[s->fbw_channels-1][s->bit_alloc.sr_code][s->frame_size_code/2];
02247     }
02248 
02249     /* set number of coefficients for each channel */
02250     for (ch = 1; ch <= s->fbw_channels; ch++) {
02251         s->start_freq[ch] = 0;
02252         for (blk = 0; blk < s->num_blocks; blk++)
02253             s->blocks[blk].end_freq[ch] = s->bandwidth_code * 3 + 73;
02254     }
02255     /* LFE channel always has 7 coefs */
02256     if (s->lfe_on) {
02257         s->start_freq[s->lfe_channel] = 0;
02258         for (blk = 0; blk < s->num_blocks; blk++)
02259             s->blocks[blk].end_freq[ch] = 7;
02260     }
02261 
02262     /* initialize coupling strategy */
02263     if (s->cpl_enabled) {
02264         if (s->options.cpl_start != AC3ENC_OPT_AUTO) {
02265             cpl_start = s->options.cpl_start;
02266         } else {
02267             cpl_start = ac3_coupling_start_tab[s->channel_mode-2][s->bit_alloc.sr_code][s->frame_size_code/2];
02268             if (cpl_start < 0) {
02269                 if (s->options.channel_coupling == AC3ENC_OPT_AUTO)
02270                     s->cpl_enabled = 0;
02271                 else
02272                     cpl_start = 15;
02273             }
02274         }
02275     }
02276     if (s->cpl_enabled) {
02277         int i, cpl_start_band, cpl_end_band;
02278         uint8_t *cpl_band_sizes = s->cpl_band_sizes;
02279 
02280         cpl_end_band   = s->bandwidth_code / 4 + 3;
02281         cpl_start_band = av_clip(cpl_start, 0, FFMIN(cpl_end_band-1, 15));
02282 
02283         s->num_cpl_subbands = cpl_end_band - cpl_start_band;
02284 
02285         s->num_cpl_bands = 1;
02286         *cpl_band_sizes  = 12;
02287         for (i = cpl_start_band + 1; i < cpl_end_band; i++) {
02288             if (ff_eac3_default_cpl_band_struct[i]) {
02289                 *cpl_band_sizes += 12;
02290             } else {
02291                 s->num_cpl_bands++;
02292                 cpl_band_sizes++;
02293                 *cpl_band_sizes = 12;
02294             }
02295         }
02296 
02297         s->start_freq[CPL_CH] = cpl_start_band * 12 + 37;
02298         s->cpl_end_freq       = cpl_end_band   * 12 + 37;
02299         for (blk = 0; blk < s->num_blocks; blk++)
02300             s->blocks[blk].end_freq[CPL_CH] = s->cpl_end_freq;
02301     }
02302 }
02303 
02304 
02305 static av_cold int allocate_buffers(AC3EncodeContext *s)
02306 {
02307     AVCodecContext *avctx = s->avctx;
02308     int blk, ch;
02309     int channels = s->channels + 1; /* includes coupling channel */
02310     int channel_blocks = channels * s->num_blocks;
02311     int total_coefs    = AC3_MAX_COEFS * channel_blocks;
02312 
02313     if (s->allocate_sample_buffers(s))
02314         goto alloc_fail;
02315 
02316     FF_ALLOC_OR_GOTO(avctx, s->bap_buffer, total_coefs *
02317                      sizeof(*s->bap_buffer), alloc_fail);
02318     FF_ALLOC_OR_GOTO(avctx, s->bap1_buffer, total_coefs *
02319                      sizeof(*s->bap1_buffer), alloc_fail);
02320     FF_ALLOCZ_OR_GOTO(avctx, s->mdct_coef_buffer, total_coefs *
02321                       sizeof(*s->mdct_coef_buffer), alloc_fail);
02322     FF_ALLOC_OR_GOTO(avctx, s->exp_buffer, total_coefs *
02323                      sizeof(*s->exp_buffer), alloc_fail);
02324     FF_ALLOC_OR_GOTO(avctx, s->grouped_exp_buffer, channel_blocks * 128 *
02325                      sizeof(*s->grouped_exp_buffer), alloc_fail);
02326     FF_ALLOC_OR_GOTO(avctx, s->psd_buffer, total_coefs *
02327                      sizeof(*s->psd_buffer), alloc_fail);
02328     FF_ALLOC_OR_GOTO(avctx, s->band_psd_buffer, channel_blocks * 64 *
02329                      sizeof(*s->band_psd_buffer), alloc_fail);
02330     FF_ALLOC_OR_GOTO(avctx, s->mask_buffer, channel_blocks * 64 *
02331                      sizeof(*s->mask_buffer), alloc_fail);
02332     FF_ALLOC_OR_GOTO(avctx, s->qmant_buffer, total_coefs *
02333                      sizeof(*s->qmant_buffer), alloc_fail);
02334     if (s->cpl_enabled) {
02335         FF_ALLOC_OR_GOTO(avctx, s->cpl_coord_exp_buffer, channel_blocks * 16 *
02336                          sizeof(*s->cpl_coord_exp_buffer), alloc_fail);
02337         FF_ALLOC_OR_GOTO(avctx, s->cpl_coord_mant_buffer, channel_blocks * 16 *
02338                          sizeof(*s->cpl_coord_mant_buffer), alloc_fail);
02339     }
02340     for (blk = 0; blk < s->num_blocks; blk++) {
02341         AC3Block *block = &s->blocks[blk];
02342         FF_ALLOCZ_OR_GOTO(avctx, block->mdct_coef, channels * sizeof(*block->mdct_coef),
02343                           alloc_fail);
02344         FF_ALLOCZ_OR_GOTO(avctx, block->exp, channels * sizeof(*block->exp),
02345                           alloc_fail);
02346         FF_ALLOCZ_OR_GOTO(avctx, block->grouped_exp, channels * sizeof(*block->grouped_exp),
02347                           alloc_fail);
02348         FF_ALLOCZ_OR_GOTO(avctx, block->psd, channels * sizeof(*block->psd),
02349                           alloc_fail);
02350         FF_ALLOCZ_OR_GOTO(avctx, block->band_psd, channels * sizeof(*block->band_psd),
02351                           alloc_fail);
02352         FF_ALLOCZ_OR_GOTO(avctx, block->mask, channels * sizeof(*block->mask),
02353                           alloc_fail);
02354         FF_ALLOCZ_OR_GOTO(avctx, block->qmant, channels * sizeof(*block->qmant),
02355                           alloc_fail);
02356         if (s->cpl_enabled) {
02357             FF_ALLOCZ_OR_GOTO(avctx, block->cpl_coord_exp, channels * sizeof(*block->cpl_coord_exp),
02358                               alloc_fail);
02359             FF_ALLOCZ_OR_GOTO(avctx, block->cpl_coord_mant, channels * sizeof(*block->cpl_coord_mant),
02360                               alloc_fail);
02361         }
02362 
02363         for (ch = 0; ch < channels; ch++) {
02364             /* arrangement: block, channel, coeff */
02365             block->grouped_exp[ch] = &s->grouped_exp_buffer[128           * (blk * channels + ch)];
02366             block->psd[ch]         = &s->psd_buffer        [AC3_MAX_COEFS * (blk * channels + ch)];
02367             block->band_psd[ch]    = &s->band_psd_buffer   [64            * (blk * channels + ch)];
02368             block->mask[ch]        = &s->mask_buffer       [64            * (blk * channels + ch)];
02369             block->qmant[ch]       = &s->qmant_buffer      [AC3_MAX_COEFS * (blk * channels + ch)];
02370             if (s->cpl_enabled) {
02371                 block->cpl_coord_exp[ch]  = &s->cpl_coord_exp_buffer [16  * (blk * channels + ch)];
02372                 block->cpl_coord_mant[ch] = &s->cpl_coord_mant_buffer[16  * (blk * channels + ch)];
02373             }
02374 
02375             /* arrangement: channel, block, coeff */
02376             block->exp[ch]         = &s->exp_buffer        [AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
02377             block->mdct_coef[ch]   = &s->mdct_coef_buffer  [AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
02378         }
02379     }
02380 
02381     if (!s->fixed_point) {
02382         FF_ALLOCZ_OR_GOTO(avctx, s->fixed_coef_buffer, total_coefs *
02383                           sizeof(*s->fixed_coef_buffer), alloc_fail);
02384         for (blk = 0; blk < s->num_blocks; blk++) {
02385             AC3Block *block = &s->blocks[blk];
02386             FF_ALLOCZ_OR_GOTO(avctx, block->fixed_coef, channels *
02387                               sizeof(*block->fixed_coef), alloc_fail);
02388             for (ch = 0; ch < channels; ch++)
02389                 block->fixed_coef[ch] = &s->fixed_coef_buffer[AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
02390         }
02391     } else {
02392         for (blk = 0; blk < s->num_blocks; blk++) {
02393             AC3Block *block = &s->blocks[blk];
02394             FF_ALLOCZ_OR_GOTO(avctx, block->fixed_coef, channels *
02395                               sizeof(*block->fixed_coef), alloc_fail);
02396             for (ch = 0; ch < channels; ch++)
02397                 block->fixed_coef[ch] = (int32_t *)block->mdct_coef[ch];
02398         }
02399     }
02400 
02401     return 0;
02402 alloc_fail:
02403     return AVERROR(ENOMEM);
02404 }
02405 
02406 
02407 av_cold int ff_ac3_encode_init(AVCodecContext *avctx)
02408 {
02409     AC3EncodeContext *s = avctx->priv_data;
02410     int ret, frame_size_58;
02411 
02412     s->avctx = avctx;
02413 
02414     s->eac3 = avctx->codec_id == CODEC_ID_EAC3;
02415 
02416     ff_ac3_common_init();
02417 
02418     ret = validate_options(s);
02419     if (ret)
02420         return ret;
02421 
02422     avctx->frame_size = AC3_BLOCK_SIZE * s->num_blocks;
02423 
02424     s->bitstream_mode = avctx->audio_service_type;
02425     if (s->bitstream_mode == AV_AUDIO_SERVICE_TYPE_KARAOKE)
02426         s->bitstream_mode = 0x7;
02427 
02428     s->bits_written    = 0;
02429     s->samples_written = 0;
02430 
02431     /* calculate crc_inv for both possible frame sizes */
02432     frame_size_58 = (( s->frame_size    >> 2) + ( s->frame_size    >> 4)) << 1;
02433     s->crc_inv[0] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);
02434     if (s->bit_alloc.sr_code == 1) {
02435         frame_size_58 = (((s->frame_size+2) >> 2) + ((s->frame_size+2) >> 4)) << 1;
02436         s->crc_inv[1] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);
02437     }
02438 
02439     /* set function pointers */
02440     if (CONFIG_AC3_FIXED_ENCODER && s->fixed_point) {
02441         s->mdct_end                     = ff_ac3_fixed_mdct_end;
02442         s->mdct_init                    = ff_ac3_fixed_mdct_init;
02443         s->allocate_sample_buffers      = ff_ac3_fixed_allocate_sample_buffers;
02444     } else if (CONFIG_AC3_ENCODER || CONFIG_EAC3_ENCODER) {
02445         s->mdct_end                     = ff_ac3_float_mdct_end;
02446         s->mdct_init                    = ff_ac3_float_mdct_init;
02447         s->allocate_sample_buffers      = ff_ac3_float_allocate_sample_buffers;
02448     }
02449     if (CONFIG_EAC3_ENCODER && s->eac3)
02450         s->output_frame_header = ff_eac3_output_frame_header;
02451     else
02452         s->output_frame_header = ac3_output_frame_header;
02453 
02454     set_bandwidth(s);
02455 
02456     exponent_init(s);
02457 
02458     bit_alloc_init(s);
02459 
02460     ret = s->mdct_init(s);
02461     if (ret)
02462         goto init_fail;
02463 
02464     ret = allocate_buffers(s);
02465     if (ret)
02466         goto init_fail;
02467 
02468     avctx->coded_frame= avcodec_alloc_frame();
02469 
02470     dsputil_init(&s->dsp, avctx);
02471     ff_ac3dsp_init(&s->ac3dsp, avctx->flags & CODEC_FLAG_BITEXACT);
02472 
02473     dprint_options(s);
02474 
02475     return 0;
02476 init_fail:
02477     ff_ac3_encode_close(avctx);
02478     return ret;
02479 }
Generated on Fri Feb 1 2013 14:34:29 for FFmpeg by doxygen 1.7.1