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Diffstat (limited to 'ffmpeg1/libavcodec/ac3enc.c')
| -rw-r--r-- | ffmpeg1/libavcodec/ac3enc.c | 2491 |
1 files changed, 2491 insertions, 0 deletions
diff --git a/ffmpeg1/libavcodec/ac3enc.c b/ffmpeg1/libavcodec/ac3enc.c new file mode 100644 index 0000000..15ff343 --- /dev/null +++ b/ffmpeg1/libavcodec/ac3enc.c @@ -0,0 +1,2491 @@ +/* + * The simplest AC-3 encoder + * Copyright (c) 2000 Fabrice Bellard + * Copyright (c) 2006-2010 Justin Ruggles <justin.ruggles@gmail.com> + * Copyright (c) 2006-2010 Prakash Punnoor <prakash@punnoor.de> + * + * This file is part of FFmpeg. + * + * FFmpeg is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * FFmpeg is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/** + * @file + * The simplest AC-3 encoder. + */ + +//#define ASSERT_LEVEL 2 + +#include <stdint.h> + +#include "libavutil/avassert.h" +#include "libavutil/avstring.h" +#include "libavutil/channel_layout.h" +#include "libavutil/crc.h" +#include "libavutil/internal.h" +#include "libavutil/opt.h" +#include "avcodec.h" +#include "put_bits.h" +#include "ac3dsp.h" +#include "ac3.h" +#include "fft.h" +#include "ac3enc.h" +#include "eac3enc.h" + +typedef struct AC3Mant { + int16_t *qmant1_ptr, *qmant2_ptr, *qmant4_ptr; ///< mantissa pointers for bap=1,2,4 + int mant1_cnt, mant2_cnt, mant4_cnt; ///< mantissa counts for bap=1,2,4 +} AC3Mant; + +#define CMIXLEV_NUM_OPTIONS 3 +static const float cmixlev_options[CMIXLEV_NUM_OPTIONS] = { + LEVEL_MINUS_3DB, LEVEL_MINUS_4POINT5DB, LEVEL_MINUS_6DB +}; + +#define SURMIXLEV_NUM_OPTIONS 3 +static const float surmixlev_options[SURMIXLEV_NUM_OPTIONS] = { + LEVEL_MINUS_3DB, LEVEL_MINUS_6DB, LEVEL_ZERO +}; + +#define EXTMIXLEV_NUM_OPTIONS 8 +static const float extmixlev_options[EXTMIXLEV_NUM_OPTIONS] = { + LEVEL_PLUS_3DB, LEVEL_PLUS_1POINT5DB, LEVEL_ONE, LEVEL_MINUS_4POINT5DB, + LEVEL_MINUS_3DB, LEVEL_MINUS_4POINT5DB, LEVEL_MINUS_6DB, LEVEL_ZERO +}; + + +/** + * LUT for number of exponent groups. + * exponent_group_tab[coupling][exponent strategy-1][number of coefficients] + */ +static uint8_t exponent_group_tab[2][3][256]; + + +/** + * List of supported channel layouts. + */ +const uint64_t ff_ac3_channel_layouts[19] = { + AV_CH_LAYOUT_MONO, + AV_CH_LAYOUT_STEREO, + AV_CH_LAYOUT_2_1, + AV_CH_LAYOUT_SURROUND, + AV_CH_LAYOUT_2_2, + AV_CH_LAYOUT_QUAD, + AV_CH_LAYOUT_4POINT0, + AV_CH_LAYOUT_5POINT0, + AV_CH_LAYOUT_5POINT0_BACK, + (AV_CH_LAYOUT_MONO | AV_CH_LOW_FREQUENCY), + (AV_CH_LAYOUT_STEREO | AV_CH_LOW_FREQUENCY), + (AV_CH_LAYOUT_2_1 | AV_CH_LOW_FREQUENCY), + (AV_CH_LAYOUT_SURROUND | AV_CH_LOW_FREQUENCY), + (AV_CH_LAYOUT_2_2 | AV_CH_LOW_FREQUENCY), + (AV_CH_LAYOUT_QUAD | AV_CH_LOW_FREQUENCY), + (AV_CH_LAYOUT_4POINT0 | AV_CH_LOW_FREQUENCY), + AV_CH_LAYOUT_5POINT1, + AV_CH_LAYOUT_5POINT1_BACK, + 0 +}; + + +/** + * LUT to select the bandwidth code based on the bit rate, sample rate, and + * number of full-bandwidth channels. + * bandwidth_tab[fbw_channels-1][sample rate code][bit rate code] + */ +static const uint8_t ac3_bandwidth_tab[5][3][19] = { +// 32 40 48 56 64 80 96 112 128 160 192 224 256 320 384 448 512 576 640 + + { { 0, 0, 0, 12, 16, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48 }, + { 0, 0, 0, 16, 20, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56 }, + { 0, 0, 0, 32, 40, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } }, + + { { 0, 0, 0, 0, 0, 0, 0, 20, 24, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48 }, + { 0, 0, 0, 0, 0, 0, 4, 24, 28, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56 }, + { 0, 0, 0, 0, 0, 0, 20, 44, 52, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } }, + + { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 24, 32, 40, 48, 48, 48, 48, 48, 48 }, + { 0, 0, 0, 0, 0, 0, 0, 0, 4, 20, 28, 36, 44, 56, 56, 56, 56, 56, 56 }, + { 0, 0, 0, 0, 0, 0, 0, 0, 20, 40, 48, 60, 60, 60, 60, 60, 60, 60, 60 } }, + + { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 24, 32, 48, 48, 48, 48, 48, 48 }, + { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 28, 36, 56, 56, 56, 56, 56, 56 }, + { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 32, 48, 60, 60, 60, 60, 60, 60, 60 } }, + + { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 20, 32, 40, 48, 48, 48, 48 }, + { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 24, 36, 44, 56, 56, 56, 56 }, + { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 28, 44, 60, 60, 60, 60, 60, 60 } } +}; + + +/** + * LUT to select the coupling start band based on the bit rate, sample rate, and + * number of full-bandwidth channels. -1 = coupling off + * ac3_coupling_start_tab[channel_mode-2][sample rate code][bit rate code] + * + * TODO: more testing for optimal parameters. + * multi-channel tests at 44.1kHz and 32kHz. + */ +static const int8_t ac3_coupling_start_tab[6][3][19] = { +// 32 40 48 56 64 80 96 112 128 160 192 224 256 320 384 448 512 576 640 + + // 2/0 + { { 0, 0, 0, 0, 0, 0, 0, 1, 1, 7, 8, 11, 12, -1, -1, -1, -1, -1, -1 }, + { 0, 0, 0, 0, 0, 0, 1, 3, 5, 7, 10, 12, 13, -1, -1, -1, -1, -1, -1 }, + { 0, 0, 0, 0, 1, 2, 2, 9, 13, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1 } }, + + // 3/0 + { { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 }, + { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 }, + { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } }, + + // 2/1 - untested + { { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 }, + { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 }, + { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } }, + + // 3/1 + { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 }, + { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 }, + { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } }, + + // 2/2 - untested + { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 }, + { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 }, + { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } }, + + // 3/2 + { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 6, 8, 11, 12, 12, -1, -1 }, + { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 6, 8, 11, 12, 12, -1, -1 }, + { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } }, +}; + + +/** + * Adjust the frame size to make the average bit rate match the target bit rate. + * This is only needed for 11025, 22050, and 44100 sample rates or any E-AC-3. + * + * @param s AC-3 encoder private context + */ +void ff_ac3_adjust_frame_size(AC3EncodeContext *s) +{ + while (s->bits_written >= s->bit_rate && s->samples_written >= s->sample_rate) { + s->bits_written -= s->bit_rate; + s->samples_written -= s->sample_rate; + } + s->frame_size = s->frame_size_min + + 2 * (s->bits_written * s->sample_rate < s->samples_written * s->bit_rate); + s->bits_written += s->frame_size * 8; + s->samples_written += AC3_BLOCK_SIZE * s->num_blocks; +} + + +/** + * Set the initial coupling strategy parameters prior to coupling analysis. + * + * @param s AC-3 encoder private context + */ +void ff_ac3_compute_coupling_strategy(AC3EncodeContext *s) +{ + int blk, ch; + int got_cpl_snr; + int num_cpl_blocks; + + /* set coupling use flags for each block/channel */ + /* TODO: turn coupling on/off and adjust start band based on bit usage */ + for (blk = 0; blk < s->num_blocks; blk++) { + AC3Block *block = &s->blocks[blk]; + for (ch = 1; ch <= s->fbw_channels; ch++) + block->channel_in_cpl[ch] = s->cpl_on; + } + + /* enable coupling for each block if at least 2 channels have coupling + enabled for that block */ + got_cpl_snr = 0; + num_cpl_blocks = 0; + for (blk = 0; blk < s->num_blocks; blk++) { + AC3Block *block = &s->blocks[blk]; + block->num_cpl_channels = 0; + for (ch = 1; ch <= s->fbw_channels; ch++) + block->num_cpl_channels += block->channel_in_cpl[ch]; + block->cpl_in_use = block->num_cpl_channels > 1; + num_cpl_blocks += block->cpl_in_use; + if (!block->cpl_in_use) { + block->num_cpl_channels = 0; + for (ch = 1; ch <= s->fbw_channels; ch++) + block->channel_in_cpl[ch] = 0; + } + + block->new_cpl_strategy = !blk; + if (blk) { + for (ch = 1; ch <= s->fbw_channels; ch++) { + if (block->channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) { + block->new_cpl_strategy = 1; + break; + } + } + } + block->new_cpl_leak = block->new_cpl_strategy; + + if (!blk || (block->cpl_in_use && !got_cpl_snr)) { + block->new_snr_offsets = 1; + if (block->cpl_in_use) + got_cpl_snr = 1; + } else { + block->new_snr_offsets = 0; + } + } + if (!num_cpl_blocks) + s->cpl_on = 0; + + /* set bandwidth for each channel */ + for (blk = 0; blk < s->num_blocks; blk++) { + AC3Block *block = &s->blocks[blk]; + for (ch = 1; ch <= s->fbw_channels; ch++) { + if (block->channel_in_cpl[ch]) + block->end_freq[ch] = s->start_freq[CPL_CH]; + else + block->end_freq[ch] = s->bandwidth_code * 3 + 73; + } + } +} + + +/** + * Apply stereo rematrixing to coefficients based on rematrixing flags. + * + * @param s AC-3 encoder private context + */ +void ff_ac3_apply_rematrixing(AC3EncodeContext *s) +{ + int nb_coefs; + int blk, bnd, i; + int start, end; + uint8_t *flags = NULL; + + if (!s->rematrixing_enabled) + return; + + for (blk = 0; blk < s->num_blocks; blk++) { + AC3Block *block = &s->blocks[blk]; + if (block->new_rematrixing_strategy) + flags = block->rematrixing_flags; + nb_coefs = FFMIN(block->end_freq[1], block->end_freq[2]); + for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++) { + if (flags[bnd]) { + start = ff_ac3_rematrix_band_tab[bnd]; + end = FFMIN(nb_coefs, ff_ac3_rematrix_band_tab[bnd+1]); + for (i = start; i < end; i++) { + int32_t lt = block->fixed_coef[1][i]; + int32_t rt = block->fixed_coef[2][i]; + block->fixed_coef[1][i] = (lt + rt) >> 1; + block->fixed_coef[2][i] = (lt - rt) >> 1; + } + } + } + } +} + + +/* + * Initialize exponent tables. + */ +static av_cold void exponent_init(AC3EncodeContext *s) +{ + int expstr, i, grpsize; + + for (expstr = EXP_D15-1; expstr <= EXP_D45-1; expstr++) { + grpsize = 3 << expstr; + for (i = 12; i < 256; i++) { + exponent_group_tab[0][expstr][i] = (i + grpsize - 4) / grpsize; + exponent_group_tab[1][expstr][i] = (i ) / grpsize; + } + } + /* LFE */ + exponent_group_tab[0][0][7] = 2; + + if (CONFIG_EAC3_ENCODER && s->eac3) + ff_eac3_exponent_init(); +} + + +/* + * Extract exponents from the MDCT coefficients. + */ +static void extract_exponents(AC3EncodeContext *s) +{ + int ch = !s->cpl_on; + int chan_size = AC3_MAX_COEFS * s->num_blocks * (s->channels - ch + 1); + AC3Block *block = &s->blocks[0]; + + s->ac3dsp.extract_exponents(block->exp[ch], block->fixed_coef[ch], chan_size); +} + + +/** + * Exponent Difference Threshold. + * New exponents are sent if their SAD exceed this number. + */ +#define EXP_DIFF_THRESHOLD 500 + +/** + * Table used to select exponent strategy based on exponent reuse block interval. + */ +static const uint8_t exp_strategy_reuse_tab[4][6] = { + { EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15 }, + { EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15 }, + { EXP_D25, EXP_D25, EXP_D15, EXP_D15, EXP_D15, EXP_D15 }, + { EXP_D45, EXP_D25, EXP_D25, EXP_D15, EXP_D15, EXP_D15 } +}; + +/* + * Calculate exponent strategies for all channels. + * Array arrangement is reversed to simplify the per-channel calculation. + */ +static void compute_exp_strategy(AC3EncodeContext *s) +{ + int ch, blk, blk1; + + for (ch = !s->cpl_on; ch <= s->fbw_channels; ch++) { + uint8_t *exp_strategy = s->exp_strategy[ch]; + uint8_t *exp = s->blocks[0].exp[ch]; + int exp_diff; + + /* estimate if the exponent variation & decide if they should be + reused in the next frame */ + exp_strategy[0] = EXP_NEW; + exp += AC3_MAX_COEFS; + for (blk = 1; blk < s->num_blocks; blk++, exp += AC3_MAX_COEFS) { + if (ch == CPL_CH) { + if (!s->blocks[blk-1].cpl_in_use) { + exp_strategy[blk] = EXP_NEW; + continue; + } else if (!s->blocks[blk].cpl_in_use) { + exp_strategy[blk] = EXP_REUSE; + continue; + } + } else if (s->blocks[blk].channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) { + exp_strategy[blk] = EXP_NEW; + continue; + } + exp_diff = s->dsp.sad[0](NULL, exp, exp - AC3_MAX_COEFS, 16, 16); + exp_strategy[blk] = EXP_REUSE; + if (ch == CPL_CH && exp_diff > (EXP_DIFF_THRESHOLD * (s->blocks[blk].end_freq[ch] - s->start_freq[ch]) / AC3_MAX_COEFS)) + exp_strategy[blk] = EXP_NEW; + else if (ch > CPL_CH && exp_diff > EXP_DIFF_THRESHOLD) + exp_strategy[blk] = EXP_NEW; + } + + /* now select the encoding strategy type : if exponents are often + recoded, we use a coarse encoding */ + blk = 0; + while (blk < s->num_blocks) { + blk1 = blk + 1; + while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE) + blk1++; + exp_strategy[blk] = exp_strategy_reuse_tab[s->num_blks_code][blk1-blk-1]; + blk = blk1; + } + } + if (s->lfe_on) { + ch = s->lfe_channel; + s->exp_strategy[ch][0] = EXP_D15; + for (blk = 1; blk < s->num_blocks; blk++) + s->exp_strategy[ch][blk] = EXP_REUSE; + } + + /* for E-AC-3, determine frame exponent strategy */ + if (CONFIG_EAC3_ENCODER && s->eac3) + ff_eac3_get_frame_exp_strategy(s); +} + + +/** + * Update the exponents so that they are the ones the decoder will decode. + * + * @param[in,out] exp array of exponents for 1 block in 1 channel + * @param nb_exps number of exponents in active bandwidth + * @param exp_strategy exponent strategy for the block + * @param cpl indicates if the block is in the coupling channel + */ +static void encode_exponents_blk_ch(uint8_t *exp, int nb_exps, int exp_strategy, + int cpl) +{ + int nb_groups, i, k; + + nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_exps] * 3; + + /* for each group, compute the minimum exponent */ + switch(exp_strategy) { + case EXP_D25: + for (i = 1, k = 1-cpl; i <= nb_groups; i++) { + uint8_t exp_min = exp[k]; + if (exp[k+1] < exp_min) + exp_min = exp[k+1]; + exp[i-cpl] = exp_min; + k += 2; + } + break; + case EXP_D45: + for (i = 1, k = 1-cpl; i <= nb_groups; i++) { + uint8_t exp_min = exp[k]; + if (exp[k+1] < exp_min) + exp_min = exp[k+1]; + if (exp[k+2] < exp_min) + exp_min = exp[k+2]; + if (exp[k+3] < exp_min) + exp_min = exp[k+3]; + exp[i-cpl] = exp_min; + k += 4; + } + break; + } + + /* constraint for DC exponent */ + if (!cpl && exp[0] > 15) + exp[0] = 15; + + /* decrease the delta between each groups to within 2 so that they can be + differentially encoded */ + for (i = 1; i <= nb_groups; i++) + exp[i] = FFMIN(exp[i], exp[i-1] + 2); + i--; + while (--i >= 0) + exp[i] = FFMIN(exp[i], exp[i+1] + 2); + + if (cpl) + exp[-1] = exp[0] & ~1; + + /* now we have the exponent values the decoder will see */ + switch (exp_strategy) { + case EXP_D25: + for (i = nb_groups, k = (nb_groups * 2)-cpl; i > 0; i--) { + uint8_t exp1 = exp[i-cpl]; + exp[k--] = exp1; + exp[k--] = exp1; + } + break; + case EXP_D45: + for (i = nb_groups, k = (nb_groups * 4)-cpl; i > 0; i--) { + exp[k] = exp[k-1] = exp[k-2] = exp[k-3] = exp[i-cpl]; + k -= 4; + } + break; + } +} + + +/* + * Encode exponents from original extracted form to what the decoder will see. + * This copies and groups exponents based on exponent strategy and reduces + * deltas between adjacent exponent groups so that they can be differentially + * encoded. + */ +static void encode_exponents(AC3EncodeContext *s) +{ + int blk, blk1, ch, cpl; + uint8_t *exp, *exp_strategy; + int nb_coefs, num_reuse_blocks; + + for (ch = !s->cpl_on; ch <= s->channels; ch++) { + exp = s->blocks[0].exp[ch] + s->start_freq[ch]; + exp_strategy = s->exp_strategy[ch]; + + cpl = (ch == CPL_CH); + blk = 0; + while (blk < s->num_blocks) { + AC3Block *block = &s->blocks[blk]; + if (cpl && !block->cpl_in_use) { + exp += AC3_MAX_COEFS; + blk++; + continue; + } + nb_coefs = block->end_freq[ch] - s->start_freq[ch]; + blk1 = blk + 1; + + /* count the number of EXP_REUSE blocks after the current block + and set exponent reference block numbers */ + s->exp_ref_block[ch][blk] = blk; + while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE) { + s->exp_ref_block[ch][blk1] = blk; + blk1++; + } + num_reuse_blocks = blk1 - blk - 1; + + /* for the EXP_REUSE case we select the min of the exponents */ + s->ac3dsp.ac3_exponent_min(exp-s->start_freq[ch], num_reuse_blocks, + AC3_MAX_COEFS); + + encode_exponents_blk_ch(exp, nb_coefs, exp_strategy[blk], cpl); + + exp += AC3_MAX_COEFS * (num_reuse_blocks + 1); + blk = blk1; + } + } + + /* reference block numbers have been changed, so reset ref_bap_set */ + s->ref_bap_set = 0; +} + + +/* + * Count exponent bits based on bandwidth, coupling, and exponent strategies. + */ +static int count_exponent_bits(AC3EncodeContext *s) +{ + int blk, ch; + int nb_groups, bit_count; + + bit_count = 0; + for (blk = 0; blk < s->num_blocks; blk++) { + AC3Block *block = &s->blocks[blk]; + for (ch = !block->cpl_in_use; ch <= s->channels; ch++) { + int exp_strategy = s->exp_strategy[ch][blk]; + int cpl = (ch == CPL_CH); + int nb_coefs = block->end_freq[ch] - s->start_freq[ch]; + + if (exp_strategy == EXP_REUSE) + continue; + + nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_coefs]; + bit_count += 4 + (nb_groups * 7); + } + } + + return bit_count; +} + + +/** + * Group exponents. + * 3 delta-encoded exponents are in each 7-bit group. The number of groups + * varies depending on exponent strategy and bandwidth. + * + * @param s AC-3 encoder private context + */ +void ff_ac3_group_exponents(AC3EncodeContext *s) +{ + int blk, ch, i, cpl; + int group_size, nb_groups; + uint8_t *p; + int delta0, delta1, delta2; + int exp0, exp1; + + for (blk = 0; blk < s->num_blocks; blk++) { + AC3Block *block = &s->blocks[blk]; + for (ch = !block->cpl_in_use; ch <= s->channels; ch++) { + int exp_strategy = s->exp_strategy[ch][blk]; + if (exp_strategy == EXP_REUSE) + continue; + cpl = (ch == CPL_CH); + group_size = exp_strategy + (exp_strategy == EXP_D45); + nb_groups = exponent_group_tab[cpl][exp_strategy-1][block->end_freq[ch]-s->start_freq[ch]]; + p = block->exp[ch] + s->start_freq[ch] - cpl; + + /* DC exponent */ + exp1 = *p++; + block->grouped_exp[ch][0] = exp1; + + /* remaining exponents are delta encoded */ + for (i = 1; i <= nb_groups; i++) { + /* merge three delta in one code */ + exp0 = exp1; + exp1 = p[0]; + p += group_size; + delta0 = exp1 - exp0 + 2; + av_assert2(delta0 >= 0 && delta0 <= 4); + + exp0 = exp1; + exp1 = p[0]; + p += group_size; + delta1 = exp1 - exp0 + 2; + av_assert2(delta1 >= 0 && delta1 <= 4); + + exp0 = exp1; + exp1 = p[0]; + p += group_size; + delta2 = exp1 - exp0 + 2; + av_assert2(delta2 >= 0 && delta2 <= 4); + + block->grouped_exp[ch][i] = ((delta0 * 5 + delta1) * 5) + delta2; + } + } + } +} + + +/** + * Calculate final exponents from the supplied MDCT coefficients and exponent shift. + * Extract exponents from MDCT coefficients, calculate exponent strategies, + * and encode final exponents. + * + * @param s AC-3 encoder private context + */ +void ff_ac3_process_exponents(AC3EncodeContext *s) +{ + extract_exponents(s); + + compute_exp_strategy(s); + + encode_exponents(s); + + emms_c(); +} + + +/* + * Count frame bits that are based solely on fixed parameters. + * This only has to be run once when the encoder is initialized. + */ +static void count_frame_bits_fixed(AC3EncodeContext *s) +{ + static const int frame_bits_inc[8] = { 0, 0, 2, 2, 2, 4, 2, 4 }; + int blk; + int frame_bits; + + /* assumptions: + * no dynamic range codes + * bit allocation parameters do not change between blocks + * no delta bit allocation + * no skipped data + * no auxiliary data + * no E-AC-3 metadata + */ + + /* header */ + frame_bits = 16; /* sync info */ + if (s->eac3) { + /* bitstream info header */ + frame_bits += 35; + frame_bits += 1 + 1; + if (s->num_blocks != 0x6) + frame_bits++; + frame_bits++; + /* audio frame header */ + if (s->num_blocks == 6) + frame_bits += 2; + frame_bits += 10; + /* exponent strategy */ + if (s->use_frame_exp_strategy) + frame_bits += 5 * s->fbw_channels; + else + frame_bits += s->num_blocks * 2 * s->fbw_channels; + if (s->lfe_on) + frame_bits += s->num_blocks; + /* converter exponent strategy */ + if (s->num_blks_code != 0x3) + frame_bits++; + else + frame_bits += s->fbw_channels * 5; + /* snr offsets */ + frame_bits += 10; + /* block start info */ + if (s->num_blocks != 1) + frame_bits++; + } else { + frame_bits += 49; + frame_bits += frame_bits_inc[s->channel_mode]; + } + + /* audio blocks */ + for (blk = 0; blk < s->num_blocks; blk++) { + if (!s->eac3) { + /* block switch flags */ + frame_bits += s->fbw_channels; + + /* dither flags */ + frame_bits += s->fbw_channels; + } + + /* dynamic range */ + frame_bits++; + + /* spectral extension */ + if (s->eac3) + frame_bits++; + + if (!s->eac3) { + /* exponent strategy */ + frame_bits += 2 * s->fbw_channels; + if (s->lfe_on) + frame_bits++; + + /* bit allocation params */ + frame_bits++; + if (!blk) + frame_bits += 2 + 2 + 2 + 2 + 3; + } + + /* converter snr offset */ + if (s->eac3) + frame_bits++; + + if (!s->eac3) { + /* delta bit allocation */ + frame_bits++; + + /* skipped data */ + frame_bits++; + } + } + + /* auxiliary data */ + frame_bits++; + + /* CRC */ + frame_bits += 1 + 16; + + s->frame_bits_fixed = frame_bits; +} + + +/* + * Initialize bit allocation. + * Set default parameter codes and calculate parameter values. + */ +static void bit_alloc_init(AC3EncodeContext *s) +{ + int ch; + + /* init default parameters */ + s->slow_decay_code = 2; + s->fast_decay_code = 1; + s->slow_gain_code = 1; + s->db_per_bit_code = s->eac3 ? 2 : 3; + s->floor_code = 7; + for (ch = 0; ch <= s->channels; ch++) + s->fast_gain_code[ch] = 4; + + /* initial snr offset */ + s->coarse_snr_offset = 40; + + /* compute real values */ + /* currently none of these values change during encoding, so we can just + set them once at initialization */ + s->bit_alloc.slow_decay = ff_ac3_slow_decay_tab[s->slow_decay_code] >> s->bit_alloc.sr_shift; + s->bit_alloc.fast_decay = ff_ac3_fast_decay_tab[s->fast_decay_code] >> s->bit_alloc.sr_shift; + s->bit_alloc.slow_gain = ff_ac3_slow_gain_tab[s->slow_gain_code]; + s->bit_alloc.db_per_bit = ff_ac3_db_per_bit_tab[s->db_per_bit_code]; + s->bit_alloc.floor = ff_ac3_floor_tab[s->floor_code]; + s->bit_alloc.cpl_fast_leak = 0; + s->bit_alloc.cpl_slow_leak = 0; + + count_frame_bits_fixed(s); +} + + +/* + * Count the bits used to encode the frame, minus exponents and mantissas. + * Bits based on fixed parameters have already been counted, so now we just + * have to add the bits based on parameters that change during encoding. + */ +static void count_frame_bits(AC3EncodeContext *s) +{ + AC3EncOptions *opt = &s->options; + int blk, ch; + int frame_bits = 0; + + /* header */ + if (s->eac3) { + if (opt->eac3_mixing_metadata) { + if (s->channel_mode > AC3_CHMODE_STEREO) + frame_bits += 2; + if (s->has_center) + frame_bits += 6; + if (s->has_surround) + frame_bits += 6; + frame_bits += s->lfe_on; + frame_bits += 1 + 1 + 2; + if (s->channel_mode < AC3_CHMODE_STEREO) + frame_bits++; + frame_bits++; + } + if (opt->eac3_info_metadata) { + frame_bits += 3 + 1 + 1; + if (s->channel_mode == AC3_CHMODE_STEREO) + frame_bits += 2 + 2; + if (s->channel_mode >= AC3_CHMODE_2F2R) + frame_bits += 2; + frame_bits++; + if (opt->audio_production_info) + frame_bits += 5 + 2 + 1; + frame_bits++; + } + /* coupling */ + if (s->channel_mode > AC3_CHMODE_MONO) { + frame_bits++; + for (blk = 1; blk < s->num_blocks; blk++) { + AC3Block *block = &s->blocks[blk]; + frame_bits++; + if (block->new_cpl_strategy) + frame_bits++; + } + } + /* coupling exponent strategy */ + if (s->cpl_on) { + if (s->use_frame_exp_strategy) { + frame_bits += 5 * s->cpl_on; + } else { + for (blk = 0; blk < s->num_blocks; blk++) + frame_bits += 2 * s->blocks[blk].cpl_in_use; + } + } + } else { + if (opt->audio_production_info) + frame_bits += 7; + if (s->bitstream_id == 6) { + if (opt->extended_bsi_1) + frame_bits += 14; + if (opt->extended_bsi_2) + frame_bits += 14; + } + } + + /* audio blocks */ + for (blk = 0; blk < s->num_blocks; blk++) { + AC3Block *block = &s->blocks[blk]; + + /* coupling strategy */ + if (!s->eac3) + frame_bits++; + if (block->new_cpl_strategy) { + if (!s->eac3) + frame_bits++; + if (block->cpl_in_use) { + if (s->eac3) + frame_bits++; + if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO) + frame_bits += s->fbw_channels; + if (s->channel_mode == AC3_CHMODE_STEREO) + frame_bits++; + frame_bits += 4 + 4; + if (s->eac3) + frame_bits++; + else + frame_bits += s->num_cpl_subbands - 1; + } + } + + /* coupling coordinates */ + if (block->cpl_in_use) { + for (ch = 1; ch <= s->fbw_channels; ch++) { + if (block->channel_in_cpl[ch]) { + if (!s->eac3 || block->new_cpl_coords[ch] != 2) + frame_bits++; + if (block->new_cpl_coords[ch]) { + frame_bits += 2; + frame_bits += (4 + 4) * s->num_cpl_bands; + } + } + } + } + + /* stereo rematrixing */ + if (s->channel_mode == AC3_CHMODE_STEREO) { + if (!s->eac3 || blk > 0) + frame_bits++; + if (s->blocks[blk].new_rematrixing_strategy) + frame_bits += block->num_rematrixing_bands; + } + + /* bandwidth codes & gain range */ + for (ch = 1; ch <= s->fbw_channels; ch++) { + if (s->exp_strategy[ch][blk] != EXP_REUSE) { + if (!block->channel_in_cpl[ch]) + frame_bits += 6; + frame_bits += 2; + } + } + + /* coupling exponent strategy */ + if (!s->eac3 && block->cpl_in_use) + frame_bits += 2; + + /* snr offsets and fast gain codes */ + if (!s->eac3) { + frame_bits++; + if (block->new_snr_offsets) + frame_bits += 6 + (s->channels + block->cpl_in_use) * (4 + 3); + } + + /* coupling leak info */ + if (block->cpl_in_use) { + if (!s->eac3 || block->new_cpl_leak != 2) + frame_bits++; + if (block->new_cpl_leak) + frame_bits += 3 + 3; + } + } + + s->frame_bits = s->frame_bits_fixed + frame_bits; +} + + +/* + * Calculate masking curve based on the final exponents. + * Also calculate the power spectral densities to use in future calculations. + */ +static void bit_alloc_masking(AC3EncodeContext *s) +{ + int blk, ch; + + for (blk = 0; blk < s->num_blocks; blk++) { + AC3Block *block = &s->blocks[blk]; + for (ch = !block->cpl_in_use; ch <= s->channels; ch++) { + /* We only need psd and mask for calculating bap. + Since we currently do not calculate bap when exponent + strategy is EXP_REUSE we do not need to calculate psd or mask. */ + if (s->exp_strategy[ch][blk] != EXP_REUSE) { + ff_ac3_bit_alloc_calc_psd(block->exp[ch], s->start_freq[ch], + block->end_freq[ch], block->psd[ch], + block->band_psd[ch]); + ff_ac3_bit_alloc_calc_mask(&s->bit_alloc, block->band_psd[ch], + s->start_freq[ch], block->end_freq[ch], + ff_ac3_fast_gain_tab[s->fast_gain_code[ch]], + ch == s->lfe_channel, + DBA_NONE, 0, NULL, NULL, NULL, + block->mask[ch]); + } + } + } +} + + +/* + * Ensure that bap for each block and channel point to the current bap_buffer. + * They may have been switched during the bit allocation search. + */ +static void reset_block_bap(AC3EncodeContext *s) +{ + int blk, ch; + uint8_t *ref_bap; + + if (s->ref_bap[0][0] == s->bap_buffer && s->ref_bap_set) + return; + + ref_bap = s->bap_buffer; + for (ch = 0; ch <= s->channels; ch++) { + for (blk = 0; blk < s->num_blocks; blk++) + s->ref_bap[ch][blk] = ref_bap + AC3_MAX_COEFS * s->exp_ref_block[ch][blk]; + ref_bap += AC3_MAX_COEFS * s->num_blocks; + } + s->ref_bap_set = 1; +} + + +/** + * Initialize mantissa counts. + * These are set so that they are padded to the next whole group size when bits + * are counted in compute_mantissa_size. + * + * @param[in,out] mant_cnt running counts for each bap value for each block + */ +static void count_mantissa_bits_init(uint16_t mant_cnt[AC3_MAX_BLOCKS][16]) +{ + int blk; + + for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) { + memset(mant_cnt[blk], 0, sizeof(mant_cnt[blk])); + mant_cnt[blk][1] = mant_cnt[blk][2] = 2; + mant_cnt[blk][4] = 1; + } +} + + +/** + * Update mantissa bit counts for all blocks in 1 channel in a given bandwidth + * range. + * + * @param s AC-3 encoder private context + * @param ch channel index + * @param[in,out] mant_cnt running counts for each bap value for each block + * @param start starting coefficient bin + * @param end ending coefficient bin + */ +static void count_mantissa_bits_update_ch(AC3EncodeContext *s, int ch, + uint16_t mant_cnt[AC3_MAX_BLOCKS][16], + int start, int end) +{ + int blk; + + for (blk = 0; blk < s->num_blocks; blk++) { + AC3Block *block = &s->blocks[blk]; + if (ch == CPL_CH && !block->cpl_in_use) + continue; + s->ac3dsp.update_bap_counts(mant_cnt[blk], + s->ref_bap[ch][blk] + start, + FFMIN(end, block->end_freq[ch]) - start); + } +} + + +/* + * Count the number of mantissa bits in the frame based on the bap values. + */ +static int count_mantissa_bits(AC3EncodeContext *s) +{ + int ch, max_end_freq; + LOCAL_ALIGNED_16(uint16_t, mant_cnt, [AC3_MAX_BLOCKS], [16]); + + count_mantissa_bits_init(mant_cnt); + + max_end_freq = s->bandwidth_code * 3 + 73; + for (ch = !s->cpl_enabled; ch <= s->channels; ch++) + count_mantissa_bits_update_ch(s, ch, mant_cnt, s->start_freq[ch], + max_end_freq); + + return s->ac3dsp.compute_mantissa_size(mant_cnt); +} + + +/** + * Run the bit allocation with a given SNR offset. + * This calculates the bit allocation pointers that will be used to determine + * the quantization of each mantissa. + * + * @param s AC-3 encoder private context + * @param snr_offset SNR offset, 0 to 1023 + * @return the number of bits needed for mantissas if the given SNR offset is + * is used. + */ +static int bit_alloc(AC3EncodeContext *s, int snr_offset) +{ + int blk, ch; + + snr_offset = (snr_offset - 240) << 2; + + reset_block_bap(s); + for (blk = 0; blk < s->num_blocks; blk++) { + AC3Block *block = &s->blocks[blk]; + + for (ch = !block->cpl_in_use; ch <= s->channels; ch++) { + /* Currently the only bit allocation parameters which vary across + blocks within a frame are the exponent values. We can take + advantage of that by reusing the bit allocation pointers + whenever we reuse exponents. */ + if (s->exp_strategy[ch][blk] != EXP_REUSE) { + s->ac3dsp.bit_alloc_calc_bap(block->mask[ch], block->psd[ch], + s->start_freq[ch], block->end_freq[ch], + snr_offset, s->bit_alloc.floor, + ff_ac3_bap_tab, s->ref_bap[ch][blk]); + } + } + } + return count_mantissa_bits(s); +} + + +/* + * Constant bitrate bit allocation search. + * Find the largest SNR offset that will allow data to fit in the frame. + */ +static int cbr_bit_allocation(AC3EncodeContext *s) +{ + int ch; + int bits_left; + int snr_offset, snr_incr; + + bits_left = 8 * s->frame_size - (s->frame_bits + s->exponent_bits); + if (bits_left < 0) + return AVERROR(EINVAL); + + snr_offset = s->coarse_snr_offset << 4; + + /* if previous frame SNR offset was 1023, check if current frame can also + use SNR offset of 1023. if so, skip the search. */ + if ((snr_offset | s->fine_snr_offset[1]) == 1023) { + if (bit_alloc(s, 1023) <= bits_left) + return 0; + } + + while (snr_offset >= 0 && + bit_alloc(s, snr_offset) > bits_left) { + snr_offset -= 64; + } + if (snr_offset < 0) + return AVERROR(EINVAL); + + FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer); + for (snr_incr = 64; snr_incr > 0; snr_incr >>= 2) { + while (snr_offset + snr_incr <= 1023 && + bit_alloc(s, snr_offset + snr_incr) <= bits_left) { + snr_offset += snr_incr; + FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer); + } + } + FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer); + reset_block_bap(s); + + s->coarse_snr_offset = snr_offset >> 4; + for (ch = !s->cpl_on; ch <= s->channels; ch++) + s->fine_snr_offset[ch] = snr_offset & 0xF; + + return 0; +} + + +/* + * Perform bit allocation search. + * Finds the SNR offset value that maximizes quality and fits in the specified + * frame size. Output is the SNR offset and a set of bit allocation pointers + * used to quantize the mantissas. + */ +int ff_ac3_compute_bit_allocation(AC3EncodeContext *s) +{ + count_frame_bits(s); + + s->exponent_bits = count_exponent_bits(s); + + bit_alloc_masking(s); + + return cbr_bit_allocation(s); +} + + +/** + * Symmetric quantization on 'levels' levels. + * + * @param c unquantized coefficient + * @param e exponent + * @param levels number of quantization levels + * @return quantized coefficient + */ +static inline int sym_quant(int c, int e, int levels) +{ + int v = (((levels * c) >> (24 - e)) + levels) >> 1; + av_assert2(v >= 0 && v < levels); + return v; +} + + +/** + * Asymmetric quantization on 2^qbits levels. + * + * @param c unquantized coefficient + * @param e exponent + * @param qbits number of quantization bits + * @return quantized coefficient + */ +static inline int asym_quant(int c, int e, int qbits) +{ + int m; + + c = (((c << e) >> (24 - qbits)) + 1) >> 1; + m = (1 << (qbits-1)); + if (c >= m) + c = m - 1; + av_assert2(c >= -m); + return c; +} + + +/** + * Quantize a set of mantissas for a single channel in a single block. + * + * @param s Mantissa count context + * @param fixed_coef unquantized fixed-point coefficients + * @param exp exponents + * @param bap bit allocation pointer indices + * @param[out] qmant quantized coefficients + * @param start_freq starting coefficient bin + * @param end_freq ending coefficient bin + */ +static void quantize_mantissas_blk_ch(AC3Mant *s, int32_t *fixed_coef, + uint8_t *exp, uint8_t *bap, + int16_t *qmant, int start_freq, + int end_freq) +{ + int i; + + for (i = start_freq; i < end_freq; i++) { + int c = fixed_coef[i]; + int e = exp[i]; + int v = bap[i]; + if (v) + switch (v) { + case 1: + v = sym_quant(c, e, 3); + switch (s->mant1_cnt) { + case 0: + s->qmant1_ptr = &qmant[i]; + v = 9 * v; + s->mant1_cnt = 1; + break; + case 1: + *s->qmant1_ptr += 3 * v; + s->mant1_cnt = 2; + v = 128; + break; + default: + *s->qmant1_ptr += v; + s->mant1_cnt = 0; + v = 128; + break; + } + break; + case 2: + v = sym_quant(c, e, 5); + switch (s->mant2_cnt) { + case 0: + s->qmant2_ptr = &qmant[i]; + v = 25 * v; + s->mant2_cnt = 1; + break; + case 1: + *s->qmant2_ptr += 5 * v; + s->mant2_cnt = 2; + v = 128; + break; + default: + *s->qmant2_ptr += v; + s->mant2_cnt = 0; + v = 128; + break; + } + break; + case 3: + v = sym_quant(c, e, 7); + break; + case 4: + v = sym_quant(c, e, 11); + switch (s->mant4_cnt) { + case 0: + s->qmant4_ptr = &qmant[i]; + v = 11 * v; + s->mant4_cnt = 1; + break; + default: + *s->qmant4_ptr += v; + s->mant4_cnt = 0; + v = 128; + break; + } + break; + case 5: + v = sym_quant(c, e, 15); + break; + case 14: + v = asym_quant(c, e, 14); + break; + case 15: + v = asym_quant(c, e, 16); + break; + default: + v = asym_quant(c, e, v - 1); + break; + } + qmant[i] = v; + } +} + + +/** + * Quantize mantissas using coefficients, exponents, and bit allocation pointers. + * + * @param s AC-3 encoder private context + */ +void ff_ac3_quantize_mantissas(AC3EncodeContext *s) +{ + int blk, ch, ch0=0, got_cpl; + + for (blk = 0; blk < s->num_blocks; blk++) { + AC3Block *block = &s->blocks[blk]; + AC3Mant m = { 0 }; + + got_cpl = !block->cpl_in_use; + for (ch = 1; ch <= s->channels; ch++) { + if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) { + ch0 = ch - 1; + ch = CPL_CH; + got_cpl = 1; + } + quantize_mantissas_blk_ch(&m, block->fixed_coef[ch], + s->blocks[s->exp_ref_block[ch][blk]].exp[ch], + s->ref_bap[ch][blk], block->qmant[ch], + s->start_freq[ch], block->end_freq[ch]); + if (ch == CPL_CH) + ch = ch0; + } + } +} + + +/* + * Write the AC-3 frame header to the output bitstream. + */ +static void ac3_output_frame_header(AC3EncodeContext *s) +{ + AC3EncOptions *opt = &s->options; + + put_bits(&s->pb, 16, 0x0b77); /* frame header */ + put_bits(&s->pb, 16, 0); /* crc1: will be filled later */ + put_bits(&s->pb, 2, s->bit_alloc.sr_code); + put_bits(&s->pb, 6, s->frame_size_code + (s->frame_size - s->frame_size_min) / 2); + put_bits(&s->pb, 5, s->bitstream_id); + put_bits(&s->pb, 3, s->bitstream_mode); + put_bits(&s->pb, 3, s->channel_mode); + if ((s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO) + put_bits(&s->pb, 2, s->center_mix_level); + if (s->channel_mode & 0x04) + put_bits(&s->pb, 2, s->surround_mix_level); + if (s->channel_mode == AC3_CHMODE_STEREO) + put_bits(&s->pb, 2, opt->dolby_surround_mode); + put_bits(&s->pb, 1, s->lfe_on); /* LFE */ + put_bits(&s->pb, 5, -opt->dialogue_level); + put_bits(&s->pb, 1, 0); /* no compression control word */ + put_bits(&s->pb, 1, 0); /* no lang code */ + put_bits(&s->pb, 1, opt->audio_production_info); + if (opt->audio_production_info) { + put_bits(&s->pb, 5, opt->mixing_level - 80); + put_bits(&s->pb, 2, opt->room_type); + } + put_bits(&s->pb, 1, opt->copyright); + put_bits(&s->pb, 1, opt->original); + if (s->bitstream_id == 6) { + /* alternate bit stream syntax */ + put_bits(&s->pb, 1, opt->extended_bsi_1); + if (opt->extended_bsi_1) { + put_bits(&s->pb, 2, opt->preferred_stereo_downmix); + put_bits(&s->pb, 3, s->ltrt_center_mix_level); + put_bits(&s->pb, 3, s->ltrt_surround_mix_level); + put_bits(&s->pb, 3, s->loro_center_mix_level); + put_bits(&s->pb, 3, s->loro_surround_mix_level); + } + put_bits(&s->pb, 1, opt->extended_bsi_2); + if (opt->extended_bsi_2) { + put_bits(&s->pb, 2, opt->dolby_surround_ex_mode); + put_bits(&s->pb, 2, opt->dolby_headphone_mode); + put_bits(&s->pb, 1, opt->ad_converter_type); + put_bits(&s->pb, 9, 0); /* xbsi2 and encinfo : reserved */ + } + } else { + put_bits(&s->pb, 1, 0); /* no time code 1 */ + put_bits(&s->pb, 1, 0); /* no time code 2 */ + } + put_bits(&s->pb, 1, 0); /* no additional bit stream info */ +} + + +/* + * Write one audio block to the output bitstream. + */ +static void output_audio_block(AC3EncodeContext *s, int blk) +{ + int ch, i, baie, bnd, got_cpl, ch0; + AC3Block *block = &s->blocks[blk]; + + /* block switching */ + if (!s->eac3) { + for (ch = 0; ch < s->fbw_channels; ch++) + put_bits(&s->pb, 1, 0); + } + + /* dither flags */ + if (!s->eac3) { + for (ch = 0; ch < s->fbw_channels; ch++) + put_bits(&s->pb, 1, 1); + } + + /* dynamic range codes */ + put_bits(&s->pb, 1, 0); + + /* spectral extension */ + if (s->eac3) + put_bits(&s->pb, 1, 0); + + /* channel coupling */ + if (!s->eac3) + put_bits(&s->pb, 1, block->new_cpl_strategy); + if (block->new_cpl_strategy) { + if (!s->eac3) + put_bits(&s->pb, 1, block->cpl_in_use); + if (block->cpl_in_use) { + int start_sub, end_sub; + if (s->eac3) + put_bits(&s->pb, 1, 0); /* enhanced coupling */ + if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO) { + for (ch = 1; ch <= s->fbw_channels; ch++) + put_bits(&s->pb, 1, block->channel_in_cpl[ch]); + } + if (s->channel_mode == AC3_CHMODE_STEREO) + put_bits(&s->pb, 1, 0); /* phase flags in use */ + start_sub = (s->start_freq[CPL_CH] - 37) / 12; + end_sub = (s->cpl_end_freq - 37) / 12; + put_bits(&s->pb, 4, start_sub); + put_bits(&s->pb, 4, end_sub - 3); + /* coupling band structure */ + if (s->eac3) { + put_bits(&s->pb, 1, 0); /* use default */ + } else { + for (bnd = start_sub+1; bnd < end_sub; bnd++) + put_bits(&s->pb, 1, ff_eac3_default_cpl_band_struct[bnd]); + } + } + } + + /* coupling coordinates */ + if (block->cpl_in_use) { + for (ch = 1; ch <= s->fbw_channels; ch++) { + if (block->channel_in_cpl[ch]) { + if (!s->eac3 || block->new_cpl_coords[ch] != 2) + put_bits(&s->pb, 1, block->new_cpl_coords[ch]); + if (block->new_cpl_coords[ch]) { + put_bits(&s->pb, 2, block->cpl_master_exp[ch]); + for (bnd = 0; bnd < s->num_cpl_bands; bnd++) { + put_bits(&s->pb, 4, block->cpl_coord_exp [ch][bnd]); + put_bits(&s->pb, 4, block->cpl_coord_mant[ch][bnd]); + } + } + } + } + } + + /* stereo rematrixing */ + if (s->channel_mode == AC3_CHMODE_STEREO) { + if (!s->eac3 || blk > 0) + put_bits(&s->pb, 1, block->new_rematrixing_strategy); + if (block->new_rematrixing_strategy) { + /* rematrixing flags */ + for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++) + put_bits(&s->pb, 1, block->rematrixing_flags[bnd]); + } + } + + /* exponent strategy */ + if (!s->eac3) { + for (ch = !block->cpl_in_use; ch <= s->fbw_channels; ch++) + put_bits(&s->pb, 2, s->exp_strategy[ch][blk]); + if (s->lfe_on) + put_bits(&s->pb, 1, s->exp_strategy[s->lfe_channel][blk]); + } + + /* bandwidth */ + for (ch = 1; ch <= s->fbw_channels; ch++) { + if (s->exp_strategy[ch][blk] != EXP_REUSE && !block->channel_in_cpl[ch]) + put_bits(&s->pb, 6, s->bandwidth_code); + } + + /* exponents */ + for (ch = !block->cpl_in_use; ch <= s->channels; ch++) { + int nb_groups; + int cpl = (ch == CPL_CH); + + if (s->exp_strategy[ch][blk] == EXP_REUSE) + continue; + + /* DC exponent */ + put_bits(&s->pb, 4, block->grouped_exp[ch][0] >> cpl); + + /* exponent groups */ + nb_groups = exponent_group_tab[cpl][s->exp_strategy[ch][blk]-1][block->end_freq[ch]-s->start_freq[ch]]; + for (i = 1; i <= nb_groups; i++) + put_bits(&s->pb, 7, block->grouped_exp[ch][i]); + + /* gain range info */ + if (ch != s->lfe_channel && !cpl) + put_bits(&s->pb, 2, 0); + } + + /* bit allocation info */ + if (!s->eac3) { + baie = (blk == 0); + put_bits(&s->pb, 1, baie); + if (baie) { + put_bits(&s->pb, 2, s->slow_decay_code); + put_bits(&s->pb, 2, s->fast_decay_code); + put_bits(&s->pb, 2, s->slow_gain_code); + put_bits(&s->pb, 2, s->db_per_bit_code); + put_bits(&s->pb, 3, s->floor_code); + } + } + + /* snr offset */ + if (!s->eac3) { + put_bits(&s->pb, 1, block->new_snr_offsets); + if (block->new_snr_offsets) { + put_bits(&s->pb, 6, s->coarse_snr_offset); + for (ch = !block->cpl_in_use; ch <= s->channels; ch++) { + put_bits(&s->pb, 4, s->fine_snr_offset[ch]); + put_bits(&s->pb, 3, s->fast_gain_code[ch]); + } + } + } else { + put_bits(&s->pb, 1, 0); /* no converter snr offset */ + } + + /* coupling leak */ + if (block->cpl_in_use) { + if (!s->eac3 || block->new_cpl_leak != 2) + put_bits(&s->pb, 1, block->new_cpl_leak); + if (block->new_cpl_leak) { + put_bits(&s->pb, 3, s->bit_alloc.cpl_fast_leak); + put_bits(&s->pb, 3, s->bit_alloc.cpl_slow_leak); + } + } + + if (!s->eac3) { + put_bits(&s->pb, 1, 0); /* no delta bit allocation */ + put_bits(&s->pb, 1, 0); /* no data to skip */ + } + + /* mantissas */ + got_cpl = !block->cpl_in_use; + for (ch = 1; ch <= s->channels; ch++) { + int b, q; + + if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) { + ch0 = ch - 1; + ch = CPL_CH; + got_cpl = 1; + } + for (i = s->start_freq[ch]; i < block->end_freq[ch]; i++) { + q = block->qmant[ch][i]; + b = s->ref_bap[ch][blk][i]; + switch (b) { + case 0: break; + case 1: if (q != 128) put_bits (&s->pb, 5, q); break; + case 2: if (q != 128) put_bits (&s->pb, 7, q); break; + case 3: put_sbits(&s->pb, 3, q); break; + case 4: if (q != 128) put_bits (&s->pb, 7, q); break; + case 14: put_sbits(&s->pb, 14, q); break; + case 15: put_sbits(&s->pb, 16, q); break; + default: put_sbits(&s->pb, b-1, q); break; + } + } + if (ch == CPL_CH) + ch = ch0; + } +} + + +/** CRC-16 Polynomial */ +#define CRC16_POLY ((1 << 0) | (1 << 2) | (1 << 15) | (1 << 16)) + + +static unsigned int mul_poly(unsigned int a, unsigned int b, unsigned int poly) +{ + unsigned int c; + + c = 0; + while (a) { + if (a & 1) + c ^= b; + a = a >> 1; + b = b << 1; + if (b & (1 << 16)) + b ^= poly; + } + return c; +} + + +static unsigned int pow_poly(unsigned int a, unsigned int n, unsigned int poly) +{ + unsigned int r; + r = 1; + while (n) { + if (n & 1) + r = mul_poly(r, a, poly); + a = mul_poly(a, a, poly); + n >>= 1; + } + return r; +} + + +/* + * Fill the end of the frame with 0's and compute the two CRCs. + */ +static void output_frame_end(AC3EncodeContext *s) +{ + const AVCRC *crc_ctx = av_crc_get_table(AV_CRC_16_ANSI); + int frame_size_58, pad_bytes, crc1, crc2_partial, crc2, crc_inv; + uint8_t *frame; + + frame_size_58 = ((s->frame_size >> 2) + (s->frame_size >> 4)) << 1; + + /* pad the remainder of the frame with zeros */ + av_assert2(s->frame_size * 8 - put_bits_count(&s->pb) >= 18); + flush_put_bits(&s->pb); + frame = s->pb.buf; + pad_bytes = s->frame_size - (put_bits_ptr(&s->pb) - frame) - 2; + av_assert2(pad_bytes >= 0); + if (pad_bytes > 0) + memset(put_bits_ptr(&s->pb), 0, pad_bytes); + + if (s->eac3) { + /* compute crc2 */ + crc2_partial = av_crc(crc_ctx, 0, frame + 2, s->frame_size - 5); + } else { + /* compute crc1 */ + /* this is not so easy because it is at the beginning of the data... */ + crc1 = av_bswap16(av_crc(crc_ctx, 0, frame + 4, frame_size_58 - 4)); + crc_inv = s->crc_inv[s->frame_size > s->frame_size_min]; + crc1 = mul_poly(crc_inv, crc1, CRC16_POLY); + AV_WB16(frame + 2, crc1); + + /* compute crc2 */ + crc2_partial = av_crc(crc_ctx, 0, frame + frame_size_58, + s->frame_size - frame_size_58 - 3); + } + crc2 = av_crc(crc_ctx, crc2_partial, frame + s->frame_size - 3, 1); + /* ensure crc2 does not match sync word by flipping crcrsv bit if needed */ + if (crc2 == 0x770B) { + frame[s->frame_size - 3] ^= 0x1; + crc2 = av_crc(crc_ctx, crc2_partial, frame + s->frame_size - 3, 1); + } + crc2 = av_bswap16(crc2); + AV_WB16(frame + s->frame_size - 2, crc2); +} + + +/** + * Write the frame to the output bitstream. + * + * @param s AC-3 encoder private context + * @param frame output data buffer + */ +void ff_ac3_output_frame(AC3EncodeContext *s, unsigned char *frame) +{ + int blk; + + init_put_bits(&s->pb, frame, AC3_MAX_CODED_FRAME_SIZE); + + s->output_frame_header(s); + + for (blk = 0; blk < s->num_blocks; blk++) + output_audio_block(s, blk); + + output_frame_end(s); +} + + +static void dprint_options(AC3EncodeContext *s) +{ +#ifdef DEBUG + AVCodecContext *avctx = s->avctx; + AC3EncOptions *opt = &s->options; + char strbuf[32]; + + switch (s->bitstream_id) { + case 6: av_strlcpy(strbuf, "AC-3 (alt syntax)", 32); break; + case 8: av_strlcpy(strbuf, "AC-3 (standard)", 32); break; + case 9: av_strlcpy(strbuf, "AC-3 (dnet half-rate)", 32); break; + case 10: av_strlcpy(strbuf, "AC-3 (dnet quater-rate)", 32); break; + case 16: av_strlcpy(strbuf, "E-AC-3 (enhanced)", 32); break; + default: snprintf(strbuf, 32, "ERROR"); + } + av_dlog(avctx, "bitstream_id: %s (%d)\n", strbuf, s->bitstream_id); + av_dlog(avctx, "sample_fmt: %s\n", av_get_sample_fmt_name(avctx->sample_fmt)); + av_get_channel_layout_string(strbuf, 32, s->channels, avctx->channel_layout); + av_dlog(avctx, "channel_layout: %s\n", strbuf); + av_dlog(avctx, "sample_rate: %d\n", s->sample_rate); + av_dlog(avctx, "bit_rate: %d\n", s->bit_rate); + av_dlog(avctx, "blocks/frame: %d (code=%d)\n", s->num_blocks, s->num_blks_code); + if (s->cutoff) + av_dlog(avctx, "cutoff: %d\n", s->cutoff); + + av_dlog(avctx, "per_frame_metadata: %s\n", + opt->allow_per_frame_metadata?"on":"off"); + if (s->has_center) + av_dlog(avctx, "center_mixlev: %0.3f (%d)\n", opt->center_mix_level, + s->center_mix_level); + else + av_dlog(avctx, "center_mixlev: {not written}\n"); + if (s->has_surround) + av_dlog(avctx, "surround_mixlev: %0.3f (%d)\n", opt->surround_mix_level, + s->surround_mix_level); + else + av_dlog(avctx, "surround_mixlev: {not written}\n"); + if (opt->audio_production_info) { + av_dlog(avctx, "mixing_level: %ddB\n", opt->mixing_level); + switch (opt->room_type) { + case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break; + case AC3ENC_OPT_LARGE_ROOM: av_strlcpy(strbuf, "large", 32); break; + case AC3ENC_OPT_SMALL_ROOM: av_strlcpy(strbuf, "small", 32); break; + default: snprintf(strbuf, 32, "ERROR (%d)", opt->room_type); + } + av_dlog(avctx, "room_type: %s\n", strbuf); + } else { + av_dlog(avctx, "mixing_level: {not written}\n"); + av_dlog(avctx, "room_type: {not written}\n"); + } + av_dlog(avctx, "copyright: %s\n", opt->copyright?"on":"off"); + av_dlog(avctx, "dialnorm: %ddB\n", opt->dialogue_level); + if (s->channel_mode == AC3_CHMODE_STEREO) { + switch (opt->dolby_surround_mode) { + case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break; + case AC3ENC_OPT_MODE_ON: av_strlcpy(strbuf, "on", 32); break; + case AC3ENC_OPT_MODE_OFF: av_strlcpy(strbuf, "off", 32); break; + default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_surround_mode); + } + av_dlog(avctx, "dsur_mode: %s\n", strbuf); + } else { + av_dlog(avctx, "dsur_mode: {not written}\n"); + } + av_dlog(avctx, "original: %s\n", opt->original?"on":"off"); + + if (s->bitstream_id == 6) { + if (opt->extended_bsi_1) { + switch (opt->preferred_stereo_downmix) { + case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break; + case AC3ENC_OPT_DOWNMIX_LTRT: av_strlcpy(strbuf, "ltrt", 32); break; + case AC3ENC_OPT_DOWNMIX_LORO: av_strlcpy(strbuf, "loro", 32); break; + default: snprintf(strbuf, 32, "ERROR (%d)", opt->preferred_stereo_downmix); + } + av_dlog(avctx, "dmix_mode: %s\n", strbuf); + av_dlog(avctx, "ltrt_cmixlev: %0.3f (%d)\n", + opt->ltrt_center_mix_level, s->ltrt_center_mix_level); + av_dlog(avctx, "ltrt_surmixlev: %0.3f (%d)\n", + opt->ltrt_surround_mix_level, s->ltrt_surround_mix_level); + av_dlog(avctx, "loro_cmixlev: %0.3f (%d)\n", + opt->loro_center_mix_level, s->loro_center_mix_level); + av_dlog(avctx, "loro_surmixlev: %0.3f (%d)\n", + opt->loro_surround_mix_level, s->loro_surround_mix_level); + } else { + av_dlog(avctx, "extended bitstream info 1: {not written}\n"); + } + if (opt->extended_bsi_2) { + switch (opt->dolby_surround_ex_mode) { + case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break; + case AC3ENC_OPT_MODE_ON: av_strlcpy(strbuf, "on", 32); break; + case AC3ENC_OPT_MODE_OFF: av_strlcpy(strbuf, "off", 32); break; + default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_surround_ex_mode); + } + av_dlog(avctx, "dsurex_mode: %s\n", strbuf); + switch (opt->dolby_headphone_mode) { + case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break; + case AC3ENC_OPT_MODE_ON: av_strlcpy(strbuf, "on", 32); break; + case AC3ENC_OPT_MODE_OFF: av_strlcpy(strbuf, "off", 32); break; + default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_headphone_mode); + } + av_dlog(avctx, "dheadphone_mode: %s\n", strbuf); + + switch (opt->ad_converter_type) { + case AC3ENC_OPT_ADCONV_STANDARD: av_strlcpy(strbuf, "standard", 32); break; + case AC3ENC_OPT_ADCONV_HDCD: av_strlcpy(strbuf, "hdcd", 32); break; + default: snprintf(strbuf, 32, "ERROR (%d)", opt->ad_converter_type); + } + av_dlog(avctx, "ad_conv_type: %s\n", strbuf); + } else { + av_dlog(avctx, "extended bitstream info 2: {not written}\n"); + } + } +#endif +} + + +#define FLT_OPTION_THRESHOLD 0.01 + +static int validate_float_option(float v, const float *v_list, int v_list_size) +{ + int i; + + for (i = 0; i < v_list_size; i++) { + if (v < (v_list[i] + FLT_OPTION_THRESHOLD) && + v > (v_list[i] - FLT_OPTION_THRESHOLD)) + break; + } + if (i == v_list_size) + return -1; + + return i; +} + + +static void validate_mix_level(void *log_ctx, const char *opt_name, + float *opt_param, const float *list, + int list_size, int default_value, int min_value, + int *ctx_param) +{ + int mixlev = validate_float_option(*opt_param, list, list_size); + if (mixlev < min_value) { + mixlev = default_value; + if (*opt_param >= 0.0) { + av_log(log_ctx, AV_LOG_WARNING, "requested %s is not valid. using " + "default value: %0.3f\n", opt_name, list[mixlev]); + } + } + *opt_param = list[mixlev]; + *ctx_param = mixlev; +} + + +/** + * Validate metadata options as set by AVOption system. + * These values can optionally be changed per-frame. + * + * @param s AC-3 encoder private context + */ +int ff_ac3_validate_metadata(AC3EncodeContext *s) +{ + AVCodecContext *avctx = s->avctx; + AC3EncOptions *opt = &s->options; + + opt->audio_production_info = 0; + opt->extended_bsi_1 = 0; + opt->extended_bsi_2 = 0; + opt->eac3_mixing_metadata = 0; + opt->eac3_info_metadata = 0; + + /* determine mixing metadata / xbsi1 use */ + if (s->channel_mode > AC3_CHMODE_STEREO && opt->preferred_stereo_downmix != AC3ENC_OPT_NONE) { + opt->extended_bsi_1 = 1; + opt->eac3_mixing_metadata = 1; + } + if (s->has_center && + (opt->ltrt_center_mix_level >= 0 || opt->loro_center_mix_level >= 0)) { + opt->extended_bsi_1 = 1; + opt->eac3_mixing_metadata = 1; + } + if (s->has_surround && + (opt->ltrt_surround_mix_level >= 0 || opt->loro_surround_mix_level >= 0)) { + opt->extended_bsi_1 = 1; + opt->eac3_mixing_metadata = 1; + } + + if (s->eac3) { + /* determine info metadata use */ + if (avctx->audio_service_type != AV_AUDIO_SERVICE_TYPE_MAIN) + opt->eac3_info_metadata = 1; + if (opt->copyright != AC3ENC_OPT_NONE || opt->original != AC3ENC_OPT_NONE) + opt->eac3_info_metadata = 1; + if (s->channel_mode == AC3_CHMODE_STEREO && + (opt->dolby_headphone_mode != AC3ENC_OPT_NONE || opt->dolby_surround_mode != AC3ENC_OPT_NONE)) + opt->eac3_info_metadata = 1; + if (s->channel_mode >= AC3_CHMODE_2F2R && opt->dolby_surround_ex_mode != AC3ENC_OPT_NONE) + opt->eac3_info_metadata = 1; + if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE || + opt->ad_converter_type != AC3ENC_OPT_NONE) { + opt->audio_production_info = 1; + opt->eac3_info_metadata = 1; + } + } else { + /* determine audio production info use */ + if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE) + opt->audio_production_info = 1; + + /* determine xbsi2 use */ + if (s->channel_mode >= AC3_CHMODE_2F2R && opt->dolby_surround_ex_mode != AC3ENC_OPT_NONE) + opt->extended_bsi_2 = 1; + if (s->channel_mode == AC3_CHMODE_STEREO && opt->dolby_headphone_mode != AC3ENC_OPT_NONE) + opt->extended_bsi_2 = 1; + if (opt->ad_converter_type != AC3ENC_OPT_NONE) + opt->extended_bsi_2 = 1; + } + + /* validate AC-3 mixing levels */ + if (!s->eac3) { + if (s->has_center) { + validate_mix_level(avctx, "center_mix_level", &opt->center_mix_level, + cmixlev_options, CMIXLEV_NUM_OPTIONS, 1, 0, + &s->center_mix_level); + } + if (s->has_surround) { + validate_mix_level(avctx, "surround_mix_level", &opt->surround_mix_level, + surmixlev_options, SURMIXLEV_NUM_OPTIONS, 1, 0, + &s->surround_mix_level); + } + } + + /* validate extended bsi 1 / mixing metadata */ + if (opt->extended_bsi_1 || opt->eac3_mixing_metadata) { + /* default preferred stereo downmix */ + if (opt->preferred_stereo_downmix == AC3ENC_OPT_NONE) + opt->preferred_stereo_downmix = AC3ENC_OPT_NOT_INDICATED; + if (!s->eac3 || s->has_center) { + /* validate Lt/Rt center mix level */ + validate_mix_level(avctx, "ltrt_center_mix_level", + &opt->ltrt_center_mix_level, extmixlev_options, + EXTMIXLEV_NUM_OPTIONS, 5, 0, + &s->ltrt_center_mix_level); + /* validate Lo/Ro center mix level */ + validate_mix_level(avctx, "loro_center_mix_level", + &opt->loro_center_mix_level, extmixlev_options, + EXTMIXLEV_NUM_OPTIONS, 5, 0, + &s->loro_center_mix_level); + } + if (!s->eac3 || s->has_surround) { + /* validate Lt/Rt surround mix level */ + validate_mix_level(avctx, "ltrt_surround_mix_level", + &opt->ltrt_surround_mix_level, extmixlev_options, + EXTMIXLEV_NUM_OPTIONS, 6, 3, + &s->ltrt_surround_mix_level); + /* validate Lo/Ro surround mix level */ + validate_mix_level(avctx, "loro_surround_mix_level", + &opt->loro_surround_mix_level, extmixlev_options, + EXTMIXLEV_NUM_OPTIONS, 6, 3, + &s->loro_surround_mix_level); + } + } + + /* validate audio service type / channels combination */ + if ((avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_KARAOKE && + avctx->channels == 1) || + ((avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_COMMENTARY || + avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_EMERGENCY || + avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_VOICE_OVER) + && avctx->channels > 1)) { + av_log(avctx, AV_LOG_ERROR, "invalid audio service type for the " + "specified number of channels\n"); + return AVERROR(EINVAL); + } + + /* validate extended bsi 2 / info metadata */ + if (opt->extended_bsi_2 || opt->eac3_info_metadata) { + /* default dolby headphone mode */ + if (opt->dolby_headphone_mode == AC3ENC_OPT_NONE) + opt->dolby_headphone_mode = AC3ENC_OPT_NOT_INDICATED; + /* default dolby surround ex mode */ + if (opt->dolby_surround_ex_mode == AC3ENC_OPT_NONE) + opt->dolby_surround_ex_mode = AC3ENC_OPT_NOT_INDICATED; + /* default A/D converter type */ + if (opt->ad_converter_type == AC3ENC_OPT_NONE) + opt->ad_converter_type = AC3ENC_OPT_ADCONV_STANDARD; + } + + /* copyright & original defaults */ + if (!s->eac3 || opt->eac3_info_metadata) { + /* default copyright */ + if (opt->copyright == AC3ENC_OPT_NONE) + opt->copyright = AC3ENC_OPT_OFF; + /* default original */ + if (opt->original == AC3ENC_OPT_NONE) + opt->original = AC3ENC_OPT_ON; + } + + /* dolby surround mode default */ + if (!s->eac3 || opt->eac3_info_metadata) { + if (opt->dolby_surround_mode == AC3ENC_OPT_NONE) + opt->dolby_surround_mode = AC3ENC_OPT_NOT_INDICATED; + } + + /* validate audio production info */ + if (opt->audio_production_info) { + if (opt->mixing_level == AC3ENC_OPT_NONE) { + av_log(avctx, AV_LOG_ERROR, "mixing_level must be set if " + "room_type is set\n"); + return AVERROR(EINVAL); + } + if (opt->mixing_level < 80) { + av_log(avctx, AV_LOG_ERROR, "invalid mixing level. must be between " + "80dB and 111dB\n"); + return AVERROR(EINVAL); + } + /* default room type */ + if (opt->room_type == AC3ENC_OPT_NONE) + opt->room_type = AC3ENC_OPT_NOT_INDICATED; + } + + /* set bitstream id for alternate bitstream syntax */ + if (!s->eac3 && (opt->extended_bsi_1 || opt->extended_bsi_2)) { + if (s->bitstream_id > 8 && s->bitstream_id < 11) { + static int warn_once = 1; + if (warn_once) { + av_log(avctx, AV_LOG_WARNING, "alternate bitstream syntax is " + "not compatible with reduced samplerates. writing of " + "extended bitstream information will be disabled.\n"); + warn_once = 0; + } + } else { + s->bitstream_id = 6; + } + } + + return 0; +} + + +/** + * Finalize encoding and free any memory allocated by the encoder. + * + * @param avctx Codec context + */ +av_cold int ff_ac3_encode_close(AVCodecContext *avctx) +{ + int blk, ch; + AC3EncodeContext *s = avctx->priv_data; + + av_freep(&s->windowed_samples); + for (ch = 0; ch < s->channels; ch++) + av_freep(&s->planar_samples[ch]); + av_freep(&s->planar_samples); + av_freep(&s->bap_buffer); + av_freep(&s->bap1_buffer); + av_freep(&s->mdct_coef_buffer); + av_freep(&s->fixed_coef_buffer); + av_freep(&s->exp_buffer); + av_freep(&s->grouped_exp_buffer); + av_freep(&s->psd_buffer); + av_freep(&s->band_psd_buffer); + av_freep(&s->mask_buffer); + av_freep(&s->qmant_buffer); + av_freep(&s->cpl_coord_exp_buffer); + av_freep(&s->cpl_coord_mant_buffer); + for (blk = 0; blk < s->num_blocks; blk++) { + AC3Block *block = &s->blocks[blk]; + av_freep(&block->mdct_coef); + av_freep(&block->fixed_coef); + av_freep(&block->exp); + av_freep(&block->grouped_exp); + av_freep(&block->psd); + av_freep(&block->band_psd); + av_freep(&block->mask); + av_freep(&block->qmant); + av_freep(&block->cpl_coord_exp); + av_freep(&block->cpl_coord_mant); + } + + s->mdct_end(s); + + return 0; +} + + +/* + * Set channel information during initialization. + */ +static av_cold int set_channel_info(AC3EncodeContext *s, int channels, + uint64_t *channel_layout) +{ + int ch_layout; + + if (channels < 1 || channels > AC3_MAX_CHANNELS) + return AVERROR(EINVAL); + if (*channel_layout > 0x7FF) + return AVERROR(EINVAL); + ch_layout = *channel_layout; + if (!ch_layout) + ch_layout = av_get_default_channel_layout(channels); + + s->lfe_on = !!(ch_layout & AV_CH_LOW_FREQUENCY); + s->channels = channels; + s->fbw_channels = channels - s->lfe_on; + s->lfe_channel = s->lfe_on ? s->fbw_channels + 1 : -1; + if (s->lfe_on) + ch_layout -= AV_CH_LOW_FREQUENCY; + + switch (ch_layout) { + case AV_CH_LAYOUT_MONO: s->channel_mode = AC3_CHMODE_MONO; break; + case AV_CH_LAYOUT_STEREO: s->channel_mode = AC3_CHMODE_STEREO; break; + case AV_CH_LAYOUT_SURROUND: s->channel_mode = AC3_CHMODE_3F; break; + case AV_CH_LAYOUT_2_1: s->channel_mode = AC3_CHMODE_2F1R; break; + case AV_CH_LAYOUT_4POINT0: s->channel_mode = AC3_CHMODE_3F1R; break; + case AV_CH_LAYOUT_QUAD: + case AV_CH_LAYOUT_2_2: s->channel_mode = AC3_CHMODE_2F2R; break; + case AV_CH_LAYOUT_5POINT0: + case AV_CH_LAYOUT_5POINT0_BACK: s->channel_mode = AC3_CHMODE_3F2R; break; + default: + return AVERROR(EINVAL); + } + s->has_center = (s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO; + s->has_surround = s->channel_mode & 0x04; + + s->channel_map = ff_ac3_enc_channel_map[s->channel_mode][s->lfe_on]; + *channel_layout = ch_layout; + if (s->lfe_on) + *channel_layout |= AV_CH_LOW_FREQUENCY; + + return 0; +} + + +static av_cold int validate_options(AC3EncodeContext *s) +{ + AVCodecContext *avctx = s->avctx; + int i, ret, max_sr; + + /* validate channel layout */ + if (!avctx->channel_layout) { + av_log(avctx, AV_LOG_WARNING, "No channel layout specified. The " + "encoder will guess the layout, but it " + "might be incorrect.\n"); + } + ret = set_channel_info(s, avctx->channels, &avctx->channel_layout); + if (ret) { + av_log(avctx, AV_LOG_ERROR, "invalid channel layout\n"); + return ret; + } + + /* validate sample rate */ + /* note: max_sr could be changed from 2 to 5 for E-AC-3 once we find a + decoder that supports half sample rate so we can validate that + the generated files are correct. */ + max_sr = s->eac3 ? 2 : 8; + for (i = 0; i <= max_sr; i++) { + if ((ff_ac3_sample_rate_tab[i % 3] >> (i / 3)) == avctx->sample_rate) + break; + } + if (i > max_sr) { + av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n"); + return AVERROR(EINVAL); + } + s->sample_rate = avctx->sample_rate; + s->bit_alloc.sr_shift = i / 3; + s->bit_alloc.sr_code = i % 3; + s->bitstream_id = s->eac3 ? 16 : 8 + s->bit_alloc.sr_shift; + + /* select a default bit rate if not set by the user */ + if (!avctx->bit_rate) { + switch (s->fbw_channels) { + case 1: avctx->bit_rate = 96000; break; + case 2: avctx->bit_rate = 192000; break; + case 3: avctx->bit_rate = 320000; break; + case 4: avctx->bit_rate = 384000; break; + case 5: avctx->bit_rate = 448000; break; + } + } + + /* validate bit rate */ + if (s->eac3) { + int max_br, min_br, wpf, min_br_dist, min_br_code; + int num_blks_code, num_blocks, frame_samples; + + /* calculate min/max bitrate */ + /* TODO: More testing with 3 and 2 blocks. All E-AC-3 samples I've + found use either 6 blocks or 1 block, even though 2 or 3 blocks + would work as far as the bit rate is concerned. */ + for (num_blks_code = 3; num_blks_code >= 0; num_blks_code--) { + num_blocks = ((int[]){ 1, 2, 3, 6 })[num_blks_code]; + frame_samples = AC3_BLOCK_SIZE * num_blocks; + max_br = 2048 * s->sample_rate / frame_samples * 16; + min_br = ((s->sample_rate + (frame_samples-1)) / frame_samples) * 16; + if (avctx->bit_rate <= max_br) + break; + } + if (avctx->bit_rate < min_br || avctx->bit_rate > max_br) { + av_log(avctx, AV_LOG_ERROR, "invalid bit rate. must be %d to %d " + "for this sample rate\n", min_br, max_br); + return AVERROR(EINVAL); + } + s->num_blks_code = num_blks_code; + s->num_blocks = num_blocks; + + /* calculate words-per-frame for the selected bitrate */ + wpf = (avctx->bit_rate / 16) * frame_samples / s->sample_rate; + av_assert1(wpf > 0 && wpf <= 2048); + + /* find the closest AC-3 bitrate code to the selected bitrate. + this is needed for lookup tables for bandwidth and coupling + parameter selection */ + min_br_code = -1; + min_br_dist = INT_MAX; + for (i = 0; i < 19; i++) { + int br_dist = abs(ff_ac3_bitrate_tab[i] * 1000 - avctx->bit_rate); + if (br_dist < min_br_dist) { + min_br_dist = br_dist; + min_br_code = i; + } + } + + /* make sure the minimum frame size is below the average frame size */ + s->frame_size_code = min_br_code << 1; + while (wpf > 1 && wpf * s->sample_rate / AC3_FRAME_SIZE * 16 > avctx->bit_rate) + wpf--; + s->frame_size_min = 2 * wpf; + } else { + int best_br = 0, best_code = 0, best_diff = INT_MAX; + for (i = 0; i < 19; i++) { + int br = (ff_ac3_bitrate_tab[i] >> s->bit_alloc.sr_shift) * 1000; + int diff = abs(br - avctx->bit_rate); + if (diff < best_diff) { + best_br = br; + best_code = i; + best_diff = diff; + } + if (!best_diff) + break; + } + avctx->bit_rate = best_br; + s->frame_size_code = best_code << 1; + s->frame_size_min = 2 * ff_ac3_frame_size_tab[s->frame_size_code][s->bit_alloc.sr_code]; + s->num_blks_code = 0x3; + s->num_blocks = 6; + } + s->bit_rate = avctx->bit_rate; + s->frame_size = s->frame_size_min; + + /* validate cutoff */ + if (avctx->cutoff < 0) { + av_log(avctx, AV_LOG_ERROR, "invalid cutoff frequency\n"); + return AVERROR(EINVAL); + } + s->cutoff = avctx->cutoff; + if (s->cutoff > (s->sample_rate >> 1)) + s->cutoff = s->sample_rate >> 1; + + ret = ff_ac3_validate_metadata(s); + if (ret) + return ret; + + s->rematrixing_enabled = s->options.stereo_rematrixing && + (s->channel_mode == AC3_CHMODE_STEREO); + + s->cpl_enabled = s->options.channel_coupling && + s->channel_mode >= AC3_CHMODE_STEREO; + + return 0; +} + + +/* + * Set bandwidth for all channels. + * The user can optionally supply a cutoff frequency. Otherwise an appropriate + * default value will be used. + */ +static av_cold void set_bandwidth(AC3EncodeContext *s) +{ + int blk, ch, cpl_start; + + if (s->cutoff) { + /* calculate bandwidth based on user-specified cutoff frequency */ + int fbw_coeffs; + fbw_coeffs = s->cutoff * 2 * AC3_MAX_COEFS / s->sample_rate; + s->bandwidth_code = av_clip((fbw_coeffs - 73) / 3, 0, 60); + } else { + /* use default bandwidth setting */ + s->bandwidth_code = ac3_bandwidth_tab[s->fbw_channels-1][s->bit_alloc.sr_code][s->frame_size_code/2]; + } + + /* set number of coefficients for each channel */ + for (ch = 1; ch <= s->fbw_channels; ch++) { + s->start_freq[ch] = 0; + for (blk = 0; blk < s->num_blocks; blk++) + s->blocks[blk].end_freq[ch] = s->bandwidth_code * 3 + 73; + } + /* LFE channel always has 7 coefs */ + if (s->lfe_on) { + s->start_freq[s->lfe_channel] = 0; + for (blk = 0; blk < s->num_blocks; blk++) + s->blocks[blk].end_freq[ch] = 7; + } + + /* initialize coupling strategy */ + if (s->cpl_enabled) { + if (s->options.cpl_start != AC3ENC_OPT_AUTO) { + cpl_start = s->options.cpl_start; + } else { + cpl_start = ac3_coupling_start_tab[s->channel_mode-2][s->bit_alloc.sr_code][s->frame_size_code/2]; + if (cpl_start < 0) { + if (s->options.channel_coupling == AC3ENC_OPT_AUTO) + s->cpl_enabled = 0; + else + cpl_start = 15; + } + } + } + if (s->cpl_enabled) { + int i, cpl_start_band, cpl_end_band; + uint8_t *cpl_band_sizes = s->cpl_band_sizes; + + cpl_end_band = s->bandwidth_code / 4 + 3; + cpl_start_band = av_clip(cpl_start, 0, FFMIN(cpl_end_band-1, 15)); + + s->num_cpl_subbands = cpl_end_band - cpl_start_band; + + s->num_cpl_bands = 1; + *cpl_band_sizes = 12; + for (i = cpl_start_band + 1; i < cpl_end_band; i++) { + if (ff_eac3_default_cpl_band_struct[i]) { + *cpl_band_sizes += 12; + } else { + s->num_cpl_bands++; + cpl_band_sizes++; + *cpl_band_sizes = 12; + } + } + + s->start_freq[CPL_CH] = cpl_start_band * 12 + 37; + s->cpl_end_freq = cpl_end_band * 12 + 37; + for (blk = 0; blk < s->num_blocks; blk++) + s->blocks[blk].end_freq[CPL_CH] = s->cpl_end_freq; + } +} + + +static av_cold int allocate_buffers(AC3EncodeContext *s) +{ + AVCodecContext *avctx = s->avctx; + int blk, ch; + int channels = s->channels + 1; /* includes coupling channel */ + int channel_blocks = channels * s->num_blocks; + int total_coefs = AC3_MAX_COEFS * channel_blocks; + + if (s->allocate_sample_buffers(s)) + goto alloc_fail; + + FF_ALLOC_OR_GOTO(avctx, s->bap_buffer, total_coefs * + sizeof(*s->bap_buffer), alloc_fail); + FF_ALLOC_OR_GOTO(avctx, s->bap1_buffer, total_coefs * + sizeof(*s->bap1_buffer), alloc_fail); + FF_ALLOCZ_OR_GOTO(avctx, s->mdct_coef_buffer, total_coefs * + sizeof(*s->mdct_coef_buffer), alloc_fail); + FF_ALLOC_OR_GOTO(avctx, s->exp_buffer, total_coefs * + sizeof(*s->exp_buffer), alloc_fail); + FF_ALLOC_OR_GOTO(avctx, s->grouped_exp_buffer, channel_blocks * 128 * + sizeof(*s->grouped_exp_buffer), alloc_fail); + FF_ALLOC_OR_GOTO(avctx, s->psd_buffer, total_coefs * + sizeof(*s->psd_buffer), alloc_fail); + FF_ALLOC_OR_GOTO(avctx, s->band_psd_buffer, channel_blocks * 64 * + sizeof(*s->band_psd_buffer), alloc_fail); + FF_ALLOC_OR_GOTO(avctx, s->mask_buffer, channel_blocks * 64 * + sizeof(*s->mask_buffer), alloc_fail); + FF_ALLOC_OR_GOTO(avctx, s->qmant_buffer, total_coefs * + sizeof(*s->qmant_buffer), alloc_fail); + if (s->cpl_enabled) { + FF_ALLOC_OR_GOTO(avctx, s->cpl_coord_exp_buffer, channel_blocks * 16 * + sizeof(*s->cpl_coord_exp_buffer), alloc_fail); + FF_ALLOC_OR_GOTO(avctx, s->cpl_coord_mant_buffer, channel_blocks * 16 * + sizeof(*s->cpl_coord_mant_buffer), alloc_fail); + } + for (blk = 0; blk < s->num_blocks; blk++) { + AC3Block *block = &s->blocks[blk]; + FF_ALLOCZ_OR_GOTO(avctx, block->mdct_coef, channels * sizeof(*block->mdct_coef), + alloc_fail); + FF_ALLOCZ_OR_GOTO(avctx, block->exp, channels * sizeof(*block->exp), + alloc_fail); + FF_ALLOCZ_OR_GOTO(avctx, block->grouped_exp, channels * sizeof(*block->grouped_exp), + alloc_fail); + FF_ALLOCZ_OR_GOTO(avctx, block->psd, channels * sizeof(*block->psd), + alloc_fail); + FF_ALLOCZ_OR_GOTO(avctx, block->band_psd, channels * sizeof(*block->band_psd), + alloc_fail); + FF_ALLOCZ_OR_GOTO(avctx, block->mask, channels * sizeof(*block->mask), + alloc_fail); + FF_ALLOCZ_OR_GOTO(avctx, block->qmant, channels * sizeof(*block->qmant), + alloc_fail); + if (s->cpl_enabled) { + FF_ALLOCZ_OR_GOTO(avctx, block->cpl_coord_exp, channels * sizeof(*block->cpl_coord_exp), + alloc_fail); + FF_ALLOCZ_OR_GOTO(avctx, block->cpl_coord_mant, channels * sizeof(*block->cpl_coord_mant), + alloc_fail); + } + + for (ch = 0; ch < channels; ch++) { + /* arrangement: block, channel, coeff */ + block->grouped_exp[ch] = &s->grouped_exp_buffer[128 * (blk * channels + ch)]; + block->psd[ch] = &s->psd_buffer [AC3_MAX_COEFS * (blk * channels + ch)]; + block->band_psd[ch] = &s->band_psd_buffer [64 * (blk * channels + ch)]; + block->mask[ch] = &s->mask_buffer [64 * (blk * channels + ch)]; + block->qmant[ch] = &s->qmant_buffer [AC3_MAX_COEFS * (blk * channels + ch)]; + if (s->cpl_enabled) { + block->cpl_coord_exp[ch] = &s->cpl_coord_exp_buffer [16 * (blk * channels + ch)]; + block->cpl_coord_mant[ch] = &s->cpl_coord_mant_buffer[16 * (blk * channels + ch)]; + } + + /* arrangement: channel, block, coeff */ + block->exp[ch] = &s->exp_buffer [AC3_MAX_COEFS * (s->num_blocks * ch + blk)]; + block->mdct_coef[ch] = &s->mdct_coef_buffer [AC3_MAX_COEFS * (s->num_blocks * ch + blk)]; + } + } + + if (!s->fixed_point) { + FF_ALLOCZ_OR_GOTO(avctx, s->fixed_coef_buffer, total_coefs * + sizeof(*s->fixed_coef_buffer), alloc_fail); + for (blk = 0; blk < s->num_blocks; blk++) { + AC3Block *block = &s->blocks[blk]; + FF_ALLOCZ_OR_GOTO(avctx, block->fixed_coef, channels * + sizeof(*block->fixed_coef), alloc_fail); + for (ch = 0; ch < channels; ch++) + block->fixed_coef[ch] = &s->fixed_coef_buffer[AC3_MAX_COEFS * (s->num_blocks * ch + blk)]; + } + } else { + for (blk = 0; blk < s->num_blocks; blk++) { + AC3Block *block = &s->blocks[blk]; + FF_ALLOCZ_OR_GOTO(avctx, block->fixed_coef, channels * + sizeof(*block->fixed_coef), alloc_fail); + for (ch = 0; ch < channels; ch++) + block->fixed_coef[ch] = (int32_t *)block->mdct_coef[ch]; + } + } + + return 0; +alloc_fail: + return AVERROR(ENOMEM); +} + + +av_cold int ff_ac3_encode_init(AVCodecContext *avctx) +{ + AC3EncodeContext *s = avctx->priv_data; + int ret, frame_size_58; + + s->avctx = avctx; + + s->eac3 = avctx->codec_id == AV_CODEC_ID_EAC3; + + ff_ac3_common_init(); + + ret = validate_options(s); + if (ret) + return ret; + + avctx->frame_size = AC3_BLOCK_SIZE * s->num_blocks; + avctx->delay = AC3_BLOCK_SIZE; + + s->bitstream_mode = avctx->audio_service_type; + if (s->bitstream_mode == AV_AUDIO_SERVICE_TYPE_KARAOKE) + s->bitstream_mode = 0x7; + + s->bits_written = 0; + s->samples_written = 0; + + /* calculate crc_inv for both possible frame sizes */ + frame_size_58 = (( s->frame_size >> 2) + ( s->frame_size >> 4)) << 1; + s->crc_inv[0] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY); + if (s->bit_alloc.sr_code == 1) { + frame_size_58 = (((s->frame_size+2) >> 2) + ((s->frame_size+2) >> 4)) << 1; + s->crc_inv[1] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY); + } + + /* set function pointers */ + if (CONFIG_AC3_FIXED_ENCODER && s->fixed_point) { + s->mdct_end = ff_ac3_fixed_mdct_end; + s->mdct_init = ff_ac3_fixed_mdct_init; + s->allocate_sample_buffers = ff_ac3_fixed_allocate_sample_buffers; + } else if (CONFIG_AC3_ENCODER || CONFIG_EAC3_ENCODER) { + s->mdct_end = ff_ac3_float_mdct_end; + s->mdct_init = ff_ac3_float_mdct_init; + s->allocate_sample_buffers = ff_ac3_float_allocate_sample_buffers; + } + if (CONFIG_EAC3_ENCODER && s->eac3) + s->output_frame_header = ff_eac3_output_frame_header; + else + s->output_frame_header = ac3_output_frame_header; + + set_bandwidth(s); + + exponent_init(s); + + bit_alloc_init(s); + + ret = s->mdct_init(s); + if (ret) + goto init_fail; + + ret = allocate_buffers(s); + if (ret) + goto init_fail; + + ff_dsputil_init(&s->dsp, avctx); + avpriv_float_dsp_init(&s->fdsp, avctx->flags & CODEC_FLAG_BITEXACT); + ff_ac3dsp_init(&s->ac3dsp, avctx->flags & CODEC_FLAG_BITEXACT); + + dprint_options(s); + + return 0; +init_fail: + ff_ac3_encode_close(avctx); + return ret; +} |