X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fac3dec.c;h=3056403dcf8c653d8207d9a79b75d06e1ff7a64c;hb=2b98377935384ecd22c2cd26106b9e03a6c9f598;hp=96296f29228b1927786b4c4bc5b5ab93d118a040;hpb=38c1a5c4d92342b03c718cdbc1e583c49460f684;p=ffmpeg diff --git a/libavcodec/ac3dec.c b/libavcodec/ac3dec.c index 96296f29228..3056403dcf8 100644 --- a/libavcodec/ac3dec.c +++ b/libavcodec/ac3dec.c @@ -1,29 +1,26 @@ /* * AC-3 Audio Decoder - * This code is developed as part of Google Summer of Code 2006 Program. + * This code was developed as part of Google Summer of Code 2006. + * E-AC-3 support was added as part of Google Summer of Code 2007. * - * Copyright (c) 2006 Kartikey Mahendra BHATT (bhattkm at gmail dot com). + * Copyright (c) 2006 Kartikey Mahendra BHATT (bhattkm at gmail dot com) + * Copyright (c) 2007-2008 Bartlomiej Wolowiec * Copyright (c) 2007 Justin Ruggles * - * Portions of this code are derived from liba52 - * http://liba52.sourceforge.net - * Copyright (C) 2000-2003 Michel Lespinasse - * Copyright (C) 1999-2000 Aaron Holtzman + * This file is part of Libav. * - * This file is part of FFmpeg. - * - * FFmpeg is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public + * Libav 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 of the License, or (at your option) any later version. + * version 2.1 of the License, or (at your option) any later version. * - * FFmpeg is distributed in the hope that it will be useful, + * Libav 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 - * General Public License for more details. + * Lesser General Public License for more details. * - * You should have received a copy of the GNU General Public - * License along with FFmpeg; if not, write to the Free Software + * You should have received a copy of the GNU Lesser General Public + * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ @@ -33,16 +30,13 @@ #include #include "libavutil/crc.h" -#include "libavutil/random.h" -#include "avcodec.h" +#include "libavutil/opt.h" +#include "internal.h" +#include "aac_ac3_parser.h" #include "ac3_parser.h" -#include "bitstream.h" -#include "dsputil.h" #include "ac3dec.h" #include "ac3dec_data.h" - -/** Maximum possible frame size when the specification limit is ignored */ -#define AC3_MAX_FRAME_SIZE 21695 +#include "kbdwin.h" /** * table for ungrouping 3 values in 7 bits. @@ -50,7 +44,6 @@ */ static uint8_t ungroup_3_in_7_bits_tab[128][3]; - /** tables for ungrouping mantissas */ static int b1_mantissas[32][3]; static int b2_mantissas[128][3]; @@ -71,16 +64,6 @@ static const uint8_t quantization_tab[16] = { static float dynamic_range_tab[256]; /** Adjustments in dB gain */ -#define LEVEL_PLUS_3DB 1.4142135623730950 -#define LEVEL_PLUS_1POINT5DB 1.1892071150027209 -#define LEVEL_MINUS_1POINT5DB 0.8408964152537145 -#define LEVEL_MINUS_3DB 0.7071067811865476 -#define LEVEL_MINUS_4POINT5DB 0.5946035575013605 -#define LEVEL_MINUS_6DB 0.5000000000000000 -#define LEVEL_MINUS_9DB 0.3535533905932738 -#define LEVEL_ZERO 0.0000000000000000 -#define LEVEL_ONE 1.0000000000000000 - static const float gain_levels[9] = { LEVEL_PLUS_3DB, LEVEL_PLUS_1POINT5DB, @@ -93,18 +76,6 @@ static const float gain_levels[9] = { LEVEL_MINUS_9DB }; -/** - * Table for center mix levels - * reference: Section 5.4.2.4 cmixlev - */ -static const uint8_t center_levels[4] = { 4, 5, 6, 5 }; - -/** - * Table for surround mix levels - * reference: Section 5.4.2.5 surmixlev - */ -static const uint8_t surround_levels[4] = { 4, 6, 7, 6 }; - /** * Table for default stereo downmixing coefficients * reference: Section 7.8.2 Downmixing Into Two Channels @@ -140,7 +111,7 @@ static av_cold void ac3_tables_init(void) /* generate table for ungrouping 3 values in 7 bits reference: Section 7.1.3 Exponent Decoding */ - for(i=0; i<128; i++) { + for (i = 0; i < 128; i++) { ungroup_3_in_7_bits_tab[i][0] = i / 25; ungroup_3_in_7_bits_tab[i][1] = (i % 25) / 5; ungroup_3_in_7_bits_tab[i][2] = (i % 25) % 5; @@ -148,13 +119,13 @@ static av_cold void ac3_tables_init(void) /* generate grouped mantissa tables reference: Section 7.3.5 Ungrouping of Mantissas */ - for(i=0; i<32; i++) { + for (i = 0; i < 32; i++) { /* bap=1 mantissas */ b1_mantissas[i][0] = symmetric_dequant(ff_ac3_ungroup_3_in_5_bits_tab[i][0], 3); b1_mantissas[i][1] = symmetric_dequant(ff_ac3_ungroup_3_in_5_bits_tab[i][1], 3); b1_mantissas[i][2] = symmetric_dequant(ff_ac3_ungroup_3_in_5_bits_tab[i][2], 3); } - for(i=0; i<128; i++) { + for (i = 0; i < 128; i++) { /* bap=2 mantissas */ b2_mantissas[i][0] = symmetric_dequant(ungroup_3_in_7_bits_tab[i][0], 5); b2_mantissas[i][1] = symmetric_dequant(ungroup_3_in_7_bits_tab[i][1], 5); @@ -166,24 +137,23 @@ static av_cold void ac3_tables_init(void) } /* generate ungrouped mantissa tables reference: Tables 7.21 and 7.23 */ - for(i=0; i<7; i++) { + for (i = 0; i < 7; i++) { /* bap=3 mantissas */ b3_mantissas[i] = symmetric_dequant(i, 7); } - for(i=0; i<15; i++) { + for (i = 0; i < 15; i++) { /* bap=5 mantissas */ b5_mantissas[i] = symmetric_dequant(i, 15); } /* generate dynamic range table reference: Section 7.7.1 Dynamic Range Control */ - for(i=0; i<256; i++) { + for (i = 0; i < 256; i++) { int v = (i >> 5) - ((i >> 7) << 3) - 5; dynamic_range_tab[i] = powf(2.0f, v) * ((i & 0x1F) | 0x20); } } - /** * AVCodec initialization */ @@ -192,21 +162,23 @@ static av_cold int ac3_decode_init(AVCodecContext *avctx) AC3DecodeContext *s = avctx->priv_data; s->avctx = avctx; - ac3_common_init(); + ff_ac3_common_init(); ac3_tables_init(); - ff_mdct_init(&s->imdct_256, 8, 1); - ff_mdct_init(&s->imdct_512, 9, 1); + ff_mdct_init(&s->imdct_256, 8, 1, 1.0); + ff_mdct_init(&s->imdct_512, 9, 1, 1.0); ff_kbd_window_init(s->window, 5.0, 256); - dsputil_init(&s->dsp, avctx); - av_init_random(0, &s->dith_state); + ff_dsputil_init(&s->dsp, avctx); + ff_ac3dsp_init(&s->ac3dsp, avctx->flags & CODEC_FLAG_BITEXACT); + ff_fmt_convert_init(&s->fmt_conv, avctx); + av_lfg_init(&s->dith_state, 0); - /* set bias values for float to int16 conversion */ - if(s->dsp.float_to_int16_interleave == ff_float_to_int16_interleave_c) { - s->add_bias = 385.0f; + /* set scale value for float to int16 conversion */ + if (avctx->request_sample_fmt == AV_SAMPLE_FMT_FLT) { s->mul_bias = 1.0f; + avctx->sample_fmt = AV_SAMPLE_FMT_FLT; } else { - s->add_bias = 0.0f; s->mul_bias = 32767.0f; + avctx->sample_fmt = AV_SAMPLE_FMT_S16; } /* allow downmixing to stereo or mono */ @@ -217,14 +189,9 @@ static av_cold int ac3_decode_init(AVCodecContext *avctx) } s->downmixed = 1; - /* allocate context input buffer */ - if (avctx->error_resilience >= FF_ER_CAREFUL) { - s->input_buffer = av_mallocz(AC3_MAX_FRAME_SIZE + FF_INPUT_BUFFER_PADDING_SIZE); - if (!s->input_buffer) - return AVERROR_NOMEM; - } + avcodec_get_frame_defaults(&s->frame); + avctx->coded_frame = &s->frame; - avctx->sample_fmt = SAMPLE_FMT_S16; return 0; } @@ -239,7 +206,7 @@ static int ac3_parse_header(AC3DecodeContext *s) int i; /* read the rest of the bsi. read twice for dual mono mode. */ - i = !(s->channel_mode); + i = !s->channel_mode; do { skip_bits(gbc, 5); // skip dialog normalization if (get_bits1(gbc)) @@ -264,7 +231,7 @@ static int ac3_parse_header(AC3DecodeContext *s) i = get_bits(gbc, 6); do { skip_bits(gbc, 8); - } while(i--); + } while (i--); } return 0; @@ -278,13 +245,15 @@ static int parse_frame_header(AC3DecodeContext *s) AC3HeaderInfo hdr; int err; - err = ff_ac3_parse_header(&s->gbc, &hdr); - if(err) + err = avpriv_ac3_parse_header(&s->gbc, &hdr); + if (err) return err; /* get decoding parameters from header info */ s->bit_alloc_params.sr_code = hdr.sr_code; + s->bitstream_mode = hdr.bitstream_mode; s->channel_mode = hdr.channel_mode; + s->channel_layout = hdr.channel_layout; s->lfe_on = hdr.lfe_on; s->bit_alloc_params.sr_shift = hdr.sr_shift; s->sample_rate = hdr.sample_rate; @@ -299,17 +268,32 @@ static int parse_frame_header(AC3DecodeContext *s) s->frame_type = hdr.frame_type; s->substreamid = hdr.substreamid; - if(s->lfe_on) { - s->start_freq[s->lfe_ch] = 0; - s->end_freq[s->lfe_ch] = 7; + if (s->lfe_on) { + s->start_freq[s->lfe_ch] = 0; + s->end_freq[s->lfe_ch] = 7; s->num_exp_groups[s->lfe_ch] = 2; s->channel_in_cpl[s->lfe_ch] = 0; } - if(hdr.bitstream_id > 10) - return AC3_PARSE_ERROR_BSID; - - return ac3_parse_header(s); + if (hdr.bitstream_id <= 10) { + s->eac3 = 0; + s->snr_offset_strategy = 2; + s->block_switch_syntax = 1; + s->dither_flag_syntax = 1; + s->bit_allocation_syntax = 1; + s->fast_gain_syntax = 0; + s->first_cpl_leak = 0; + s->dba_syntax = 1; + s->skip_syntax = 1; + memset(s->channel_uses_aht, 0, sizeof(s->channel_uses_aht)); + return ac3_parse_header(s); + } else if (CONFIG_EAC3_DECODER) { + s->eac3 = 1; + return ff_eac3_parse_header(s); + } else { + av_log(s->avctx, AV_LOG_ERROR, "E-AC-3 support not compiled in\n"); + return -1; + } } /** @@ -319,42 +303,43 @@ static int parse_frame_header(AC3DecodeContext *s) static void set_downmix_coeffs(AC3DecodeContext *s) { int i; - float cmix = gain_levels[center_levels[s->center_mix_level]]; - float smix = gain_levels[surround_levels[s->surround_mix_level]]; + float cmix = gain_levels[s-> center_mix_level]; + float smix = gain_levels[s->surround_mix_level]; float norm0, norm1; - for(i=0; ifbw_channels; i++) { + for (i = 0; i < s->fbw_channels; i++) { s->downmix_coeffs[i][0] = gain_levels[ac3_default_coeffs[s->channel_mode][i][0]]; s->downmix_coeffs[i][1] = gain_levels[ac3_default_coeffs[s->channel_mode][i][1]]; } - if(s->channel_mode > 1 && s->channel_mode & 1) { + if (s->channel_mode > 1 && s->channel_mode & 1) { s->downmix_coeffs[1][0] = s->downmix_coeffs[1][1] = cmix; } - if(s->channel_mode == AC3_CHMODE_2F1R || s->channel_mode == AC3_CHMODE_3F1R) { + if (s->channel_mode == AC3_CHMODE_2F1R || s->channel_mode == AC3_CHMODE_3F1R) { int nf = s->channel_mode - 2; s->downmix_coeffs[nf][0] = s->downmix_coeffs[nf][1] = smix * LEVEL_MINUS_3DB; } - if(s->channel_mode == AC3_CHMODE_2F2R || s->channel_mode == AC3_CHMODE_3F2R) { + if (s->channel_mode == AC3_CHMODE_2F2R || s->channel_mode == AC3_CHMODE_3F2R) { int nf = s->channel_mode - 4; s->downmix_coeffs[nf][0] = s->downmix_coeffs[nf+1][1] = smix; } /* renormalize */ norm0 = norm1 = 0.0; - for(i=0; ifbw_channels; i++) { + for (i = 0; i < s->fbw_channels; i++) { norm0 += s->downmix_coeffs[i][0]; norm1 += s->downmix_coeffs[i][1]; } norm0 = 1.0f / norm0; norm1 = 1.0f / norm1; - for(i=0; ifbw_channels; i++) { + for (i = 0; i < s->fbw_channels; i++) { s->downmix_coeffs[i][0] *= norm0; s->downmix_coeffs[i][1] *= norm1; } - if(s->output_mode == AC3_CHMODE_MONO) { - for(i=0; ifbw_channels; i++) - s->downmix_coeffs[i][0] = (s->downmix_coeffs[i][0] + s->downmix_coeffs[i][1]) * LEVEL_MINUS_3DB; + if (s->output_mode == AC3_CHMODE_MONO) { + for (i = 0; i < s->fbw_channels; i++) + s->downmix_coeffs[i][0] = (s->downmix_coeffs[i][0] + + s->downmix_coeffs[i][1]) * LEVEL_MINUS_3DB; } } @@ -362,8 +347,8 @@ static void set_downmix_coeffs(AC3DecodeContext *s) * Decode the grouped exponents according to exponent strategy. * reference: Section 7.1.3 Exponent Decoding */ -static void decode_exponents(GetBitContext *gbc, int exp_strategy, int ngrps, - uint8_t absexp, int8_t *dexps) +static int decode_exponents(GetBitContext *gbc, int exp_strategy, int ngrps, + uint8_t absexp, int8_t *dexps) { int i, j, grp, group_size; int dexp[256]; @@ -371,7 +356,7 @@ static void decode_exponents(GetBitContext *gbc, int exp_strategy, int ngrps, /* unpack groups */ group_size = exp_strategy + (exp_strategy == EXP_D45); - for(grp=0,i=0; grp 24U) + return -1; + switch (group_size) { + case 4: dexps[j++] = prevexp; + dexps[j++] = prevexp; + case 2: dexps[j++] = prevexp; + case 1: dexps[j++] = prevexp; } } + return 0; } /** @@ -395,24 +386,26 @@ static void decode_exponents(GetBitContext *gbc, int exp_strategy, int ngrps, */ static void calc_transform_coeffs_cpl(AC3DecodeContext *s) { - int i, j, ch, bnd, subbnd; + int bin, band, ch; - subbnd = -1; - i = s->start_freq[CPL_CH]; - for(bnd=0; bndnum_cpl_bands; bnd++) { - do { - subbnd++; - for(j=0; j<12; j++) { - for(ch=1; ch<=s->fbw_channels; ch++) { - if(s->channel_in_cpl[ch]) { - s->fixed_coeffs[ch][i] = ((int64_t)s->fixed_coeffs[CPL_CH][i] * (int64_t)s->cpl_coords[ch][bnd]) >> 23; - if (ch == 2 && s->phase_flags[bnd]) - s->fixed_coeffs[ch][i] = -s->fixed_coeffs[ch][i]; - } + bin = s->start_freq[CPL_CH]; + for (band = 0; band < s->num_cpl_bands; band++) { + int band_start = bin; + int band_end = bin + s->cpl_band_sizes[band]; + for (ch = 1; ch <= s->fbw_channels; ch++) { + if (s->channel_in_cpl[ch]) { + int cpl_coord = s->cpl_coords[ch][band] << 5; + for (bin = band_start; bin < band_end; bin++) { + s->fixed_coeffs[ch][bin] = + MULH(s->fixed_coeffs[CPL_CH][bin] << 4, cpl_coord); + } + if (ch == 2 && s->phase_flags[band]) { + for (bin = band_start; bin < band_end; bin++) + s->fixed_coeffs[2][bin] = -s->fixed_coeffs[2][bin]; } - i++; } - } while(s->cpl_band_struct[subbnd]); + } + bin = band_end; } } @@ -420,142 +413,144 @@ static void calc_transform_coeffs_cpl(AC3DecodeContext *s) * Grouped mantissas for 3-level 5-level and 11-level quantization */ typedef struct { - int b1_mant[3]; - int b2_mant[3]; - int b4_mant[2]; - int b1ptr; - int b2ptr; - int b4ptr; + int b1_mant[2]; + int b2_mant[2]; + int b4_mant; + int b1; + int b2; + int b4; } mant_groups; /** - * Get the transform coefficients for a particular channel + * Decode the transform coefficients for a particular channel * reference: Section 7.3 Quantization and Decoding of Mantissas */ -static void get_transform_coeffs_ch(AC3DecodeContext *s, int ch_index, mant_groups *m) +static void ac3_decode_transform_coeffs_ch(AC3DecodeContext *s, int ch_index, mant_groups *m) { + int start_freq = s->start_freq[ch_index]; + int end_freq = s->end_freq[ch_index]; + uint8_t *baps = s->bap[ch_index]; + int8_t *exps = s->dexps[ch_index]; + int *coeffs = s->fixed_coeffs[ch_index]; + int dither = (ch_index == CPL_CH) || s->dither_flag[ch_index]; GetBitContext *gbc = &s->gbc; - int i, gcode, tbap, start, end; - uint8_t *exps; - uint8_t *bap; - int *coeffs; - - exps = s->dexps[ch_index]; - bap = s->bap[ch_index]; - coeffs = s->fixed_coeffs[ch_index]; - start = s->start_freq[ch_index]; - end = s->end_freq[ch_index]; - - for (i = start; i < end; i++) { - tbap = bap[i]; - switch (tbap) { - case 0: - coeffs[i] = (av_random(&s->dith_state) & 0x7FFFFF) - 0x400000; - break; - - case 1: - if(m->b1ptr > 2) { - gcode = get_bits(gbc, 5); - m->b1_mant[0] = b1_mantissas[gcode][0]; - m->b1_mant[1] = b1_mantissas[gcode][1]; - m->b1_mant[2] = b1_mantissas[gcode][2]; - m->b1ptr = 0; - } - coeffs[i] = m->b1_mant[m->b1ptr++]; - break; - - case 2: - if(m->b2ptr > 2) { - gcode = get_bits(gbc, 7); - m->b2_mant[0] = b2_mantissas[gcode][0]; - m->b2_mant[1] = b2_mantissas[gcode][1]; - m->b2_mant[2] = b2_mantissas[gcode][2]; - m->b2ptr = 0; - } - coeffs[i] = m->b2_mant[m->b2ptr++]; - break; - - case 3: - coeffs[i] = b3_mantissas[get_bits(gbc, 3)]; - break; - - case 4: - if(m->b4ptr > 1) { - gcode = get_bits(gbc, 7); - m->b4_mant[0] = b4_mantissas[gcode][0]; - m->b4_mant[1] = b4_mantissas[gcode][1]; - m->b4ptr = 0; - } - coeffs[i] = m->b4_mant[m->b4ptr++]; - break; - - case 5: - coeffs[i] = b5_mantissas[get_bits(gbc, 4)]; - break; - - default: { - /* asymmetric dequantization */ - int qlevel = quantization_tab[tbap]; - coeffs[i] = get_sbits(gbc, qlevel) << (24 - qlevel); - break; + int freq; + + for (freq = start_freq; freq < end_freq; freq++) { + int bap = baps[freq]; + int mantissa; + switch (bap) { + case 0: + if (dither) + mantissa = (av_lfg_get(&s->dith_state) & 0x7FFFFF) - 0x400000; + else + mantissa = 0; + break; + case 1: + if (m->b1) { + m->b1--; + mantissa = m->b1_mant[m->b1]; + } else { + int bits = get_bits(gbc, 5); + mantissa = b1_mantissas[bits][0]; + m->b1_mant[1] = b1_mantissas[bits][1]; + m->b1_mant[0] = b1_mantissas[bits][2]; + m->b1 = 2; + } + break; + case 2: + if (m->b2) { + m->b2--; + mantissa = m->b2_mant[m->b2]; + } else { + int bits = get_bits(gbc, 7); + mantissa = b2_mantissas[bits][0]; + m->b2_mant[1] = b2_mantissas[bits][1]; + m->b2_mant[0] = b2_mantissas[bits][2]; + m->b2 = 2; + } + break; + case 3: + mantissa = b3_mantissas[get_bits(gbc, 3)]; + break; + case 4: + if (m->b4) { + m->b4 = 0; + mantissa = m->b4_mant; + } else { + int bits = get_bits(gbc, 7); + mantissa = b4_mantissas[bits][0]; + m->b4_mant = b4_mantissas[bits][1]; + m->b4 = 1; } + break; + case 5: + mantissa = b5_mantissas[get_bits(gbc, 4)]; + break; + default: /* 6 to 15 */ + /* Shift mantissa and sign-extend it. */ + mantissa = get_sbits(gbc, quantization_tab[bap]); + mantissa <<= 24 - quantization_tab[bap]; + break; } - coeffs[i] >>= exps[i]; + coeffs[freq] = mantissa >> exps[freq]; } } /** - * Remove random dithering from coefficients with zero-bit mantissas + * Remove random dithering from coupling range coefficients with zero-bit + * mantissas for coupled channels which do not use dithering. * reference: Section 7.3.4 Dither for Zero Bit Mantissas (bap=0) */ static void remove_dithering(AC3DecodeContext *s) { int ch, i; - int end=0; - int *coeffs; - uint8_t *bap; - - for(ch=1; ch<=s->fbw_channels; ch++) { - if(!s->dither_flag[ch]) { - coeffs = s->fixed_coeffs[ch]; - bap = s->bap[ch]; - if(s->channel_in_cpl[ch]) - end = s->start_freq[CPL_CH]; - else - end = s->end_freq[ch]; - for(i=0; ichannel_in_cpl[ch]) { - bap = s->bap[CPL_CH]; - for(; iend_freq[CPL_CH]; i++) { - if(!bap[i]) - coeffs[i] = 0; - } + + for (ch = 1; ch <= s->fbw_channels; ch++) { + if (!s->dither_flag[ch] && s->channel_in_cpl[ch]) { + for (i = s->start_freq[CPL_CH]; i < s->end_freq[CPL_CH]; i++) { + if (!s->bap[CPL_CH][i]) + s->fixed_coeffs[ch][i] = 0; } } } } +static void decode_transform_coeffs_ch(AC3DecodeContext *s, int blk, int ch, + mant_groups *m) +{ + if (!s->channel_uses_aht[ch]) { + ac3_decode_transform_coeffs_ch(s, ch, m); + } else { + /* if AHT is used, mantissas for all blocks are encoded in the first + block of the frame. */ + int bin; + if (!blk && CONFIG_EAC3_DECODER) + ff_eac3_decode_transform_coeffs_aht_ch(s, ch); + for (bin = s->start_freq[ch]; bin < s->end_freq[ch]; bin++) { + s->fixed_coeffs[ch][bin] = s->pre_mantissa[ch][bin][blk] >> s->dexps[ch][bin]; + } + } +} + /** - * Get the transform coefficients. + * Decode the transform coefficients. */ -static void get_transform_coeffs(AC3DecodeContext *s) +static void decode_transform_coeffs(AC3DecodeContext *s, int blk) { int ch, end; int got_cplchan = 0; mant_groups m; - m.b1ptr = m.b2ptr = m.b4ptr = 3; + m.b1 = m.b2 = m.b4 = 0; for (ch = 1; ch <= s->channels; ch++) { /* transform coefficients for full-bandwidth channel */ - get_transform_coeffs_ch(s, ch, &m); + decode_transform_coeffs_ch(s, blk, ch, &m); /* tranform coefficients for coupling channel come right after the coefficients for the first coupled channel*/ if (s->channel_in_cpl[ch]) { if (!got_cplchan) { - get_transform_coeffs_ch(s, CPL_CH, &m); + decode_transform_coeffs_ch(s, blk, CPL_CH, &m); calc_transform_coeffs_cpl(s); got_cplchan = 1; } @@ -565,12 +560,11 @@ static void get_transform_coeffs(AC3DecodeContext *s) } do s->fixed_coeffs[ch][end] = 0; - while(++end < 256); + while (++end < 256); } - /* if any channel doesn't use dithering, zero appropriate coefficients */ - if(!s->dither_all) - remove_dithering(s); + /* zero the dithered coefficients for appropriate channels */ + remove_dithering(s); } /** @@ -581,18 +575,16 @@ static void do_rematrixing(AC3DecodeContext *s) { int bnd, i; int end, bndend; - int tmp0, tmp1; end = FFMIN(s->end_freq[1], s->end_freq[2]); - for(bnd=0; bndnum_rematrixing_bands; bnd++) { - if(s->rematrixing_flags[bnd]) { - bndend = FFMIN(end, ff_ac3_rematrix_band_tab[bnd+1]); - for(i=ff_ac3_rematrix_band_tab[bnd]; ifixed_coeffs[1][i]; - tmp1 = s->fixed_coeffs[2][i]; - s->fixed_coeffs[1][i] = tmp0 + tmp1; - s->fixed_coeffs[2][i] = tmp0 - tmp1; + for (bnd = 0; bnd < s->num_rematrixing_bands; bnd++) { + if (s->rematrixing_flags[bnd]) { + bndend = FFMIN(end, ff_ac3_rematrix_band_tab[bnd + 1]); + for (i = ff_ac3_rematrix_band_tab[bnd]; i < bndend; i++) { + int tmp0 = s->fixed_coeffs[1][i]; + s->fixed_coeffs[1][i] += s->fixed_coeffs[2][i]; + s->fixed_coeffs[2][i] = tmp0 - s->fixed_coeffs[2][i]; } } } @@ -606,25 +598,24 @@ static void do_rematrixing(AC3DecodeContext *s) static inline void do_imdct(AC3DecodeContext *s, int channels) { int ch; - float add_bias = s->add_bias; - if(s->out_channels==1 && channels>1) - add_bias *= LEVEL_MINUS_3DB; // compensate for the gain in downmix - for (ch=1; ch<=channels; ch++) { + for (ch = 1; ch <= channels; ch++) { if (s->block_switch[ch]) { int i; - float *x = s->tmp_output+128; - for(i=0; i<128; i++) - x[i] = s->transform_coeffs[ch][2*i]; - ff_imdct_half(&s->imdct_256, s->tmp_output, x); - s->dsp.vector_fmul_window(s->output[ch-1], s->delay[ch-1], s->tmp_output, s->window, add_bias, 128); - for(i=0; i<128; i++) - x[i] = s->transform_coeffs[ch][2*i+1]; - ff_imdct_half(&s->imdct_256, s->delay[ch-1], x); + float *x = s->tmp_output + 128; + for (i = 0; i < 128; i++) + x[i] = s->transform_coeffs[ch][2 * i]; + s->imdct_256.imdct_half(&s->imdct_256, s->tmp_output, x); + s->dsp.vector_fmul_window(s->output[ch - 1], s->delay[ch - 1], + s->tmp_output, s->window, 128); + for (i = 0; i < 128; i++) + x[i] = s->transform_coeffs[ch][2 * i + 1]; + s->imdct_256.imdct_half(&s->imdct_256, s->delay[ch - 1], x); } else { - ff_imdct_half(&s->imdct_512, s->tmp_output, s->transform_coeffs[ch]); - s->dsp.vector_fmul_window(s->output[ch-1], s->delay[ch-1], s->tmp_output, s->window, add_bias, 128); - memcpy(s->delay[ch-1], s->tmp_output+128, 128*sizeof(float)); + s->imdct_512.imdct_half(&s->imdct_512, s->tmp_output, s->transform_coeffs[ch]); + s->dsp.vector_fmul_window(s->output[ch - 1], s->delay[ch - 1], + s->tmp_output, s->window, 128); + memcpy(s->delay[ch - 1], s->tmp_output + 128, 128 * sizeof(float)); } } } @@ -632,24 +623,25 @@ static inline void do_imdct(AC3DecodeContext *s, int channels) /** * Downmix the output to mono or stereo. */ -void ff_ac3_downmix_c(float (*samples)[256], float (*matrix)[2], int out_ch, int in_ch, int len) +void ff_ac3_downmix_c(float (*samples)[256], float (*matrix)[2], + int out_ch, int in_ch, int len) { int i, j; float v0, v1; - if(out_ch == 2) { - for(i=0; ichannel_mode) { - case AC3_CHMODE_DUALMONO: - case AC3_CHMODE_STEREO: - /* upmix mono to stereo */ - memcpy(s->delay[1], s->delay[0], channel_data_size); - break; - case AC3_CHMODE_2F2R: - memset(s->delay[3], 0, channel_data_size); - case AC3_CHMODE_2F1R: - memset(s->delay[2], 0, channel_data_size); - break; - case AC3_CHMODE_3F2R: - memset(s->delay[4], 0, channel_data_size); - case AC3_CHMODE_3F1R: - memset(s->delay[3], 0, channel_data_size); - case AC3_CHMODE_3F: - memcpy(s->delay[2], s->delay[1], channel_data_size); - memset(s->delay[1], 0, channel_data_size); - break; + int channel_data_size = sizeof(s->delay[0]); + switch (s->channel_mode) { + case AC3_CHMODE_DUALMONO: + case AC3_CHMODE_STEREO: + /* upmix mono to stereo */ + memcpy(s->delay[1], s->delay[0], channel_data_size); + break; + case AC3_CHMODE_2F2R: + memset(s->delay[3], 0, channel_data_size); + case AC3_CHMODE_2F1R: + memset(s->delay[2], 0, channel_data_size); + break; + case AC3_CHMODE_3F2R: + memset(s->delay[4], 0, channel_data_size); + case AC3_CHMODE_3F1R: + memset(s->delay[3], 0, channel_data_size); + case AC3_CHMODE_3F: + memcpy(s->delay[2], s->delay[1], channel_data_size); + memset(s->delay[1], 0, channel_data_size); + break; } } +/** + * Decode band structure for coupling, spectral extension, or enhanced coupling. + * The band structure defines how many subbands are in each band. For each + * subband in the range, 1 means it is combined with the previous band, and 0 + * means that it starts a new band. + * + * @param[in] gbc bit reader context + * @param[in] blk block number + * @param[in] eac3 flag to indicate E-AC-3 + * @param[in] ecpl flag to indicate enhanced coupling + * @param[in] start_subband subband number for start of range + * @param[in] end_subband subband number for end of range + * @param[in] default_band_struct default band structure table + * @param[out] num_bands number of bands (optionally NULL) + * @param[out] band_sizes array containing the number of bins in each band (optionally NULL) + */ +static void decode_band_structure(GetBitContext *gbc, int blk, int eac3, + int ecpl, int start_subband, int end_subband, + const uint8_t *default_band_struct, + int *num_bands, uint8_t *band_sizes) +{ + int subbnd, bnd, n_subbands, n_bands=0; + uint8_t bnd_sz[22]; + uint8_t coded_band_struct[22]; + const uint8_t *band_struct; + + n_subbands = end_subband - start_subband; + + /* decode band structure from bitstream or use default */ + if (!eac3 || get_bits1(gbc)) { + for (subbnd = 0; subbnd < n_subbands - 1; subbnd++) { + coded_band_struct[subbnd] = get_bits1(gbc); + } + band_struct = coded_band_struct; + } else if (!blk) { + band_struct = &default_band_struct[start_subband+1]; + } else { + /* no change in band structure */ + return; + } + + /* calculate number of bands and band sizes based on band structure. + note that the first 4 subbands in enhanced coupling span only 6 bins + instead of 12. */ + if (num_bands || band_sizes ) { + n_bands = n_subbands; + bnd_sz[0] = ecpl ? 6 : 12; + for (bnd = 0, subbnd = 1; subbnd < n_subbands; subbnd++) { + int subbnd_size = (ecpl && subbnd < 4) ? 6 : 12; + if (band_struct[subbnd - 1]) { + n_bands--; + bnd_sz[bnd] += subbnd_size; + } else { + bnd_sz[++bnd] = subbnd_size; + } + } + } + + /* set optional output params */ + if (num_bands) + *num_bands = n_bands; + if (band_sizes) + memcpy(band_sizes, bnd_sz, n_bands); +} + /** * Decode a single audio block from the AC-3 bitstream. */ @@ -696,85 +753,206 @@ static int decode_audio_block(AC3DecodeContext *s, int blk) int downmix_output; int cpl_in_use; GetBitContext *gbc = &s->gbc; - uint8_t bit_alloc_stages[AC3_MAX_CHANNELS]; - - memset(bit_alloc_stages, 0, AC3_MAX_CHANNELS); + uint8_t bit_alloc_stages[AC3_MAX_CHANNELS] = { 0 }; /* block switch flags */ different_transforms = 0; - for (ch = 1; ch <= fbw_channels; ch++) { - s->block_switch[ch] = get_bits1(gbc); - if(ch > 1 && s->block_switch[ch] != s->block_switch[1]) - different_transforms = 1; + if (s->block_switch_syntax) { + for (ch = 1; ch <= fbw_channels; ch++) { + s->block_switch[ch] = get_bits1(gbc); + if (ch > 1 && s->block_switch[ch] != s->block_switch[1]) + different_transforms = 1; + } } /* dithering flags */ - s->dither_all = 1; - for (ch = 1; ch <= fbw_channels; ch++) { - s->dither_flag[ch] = get_bits1(gbc); - if(!s->dither_flag[ch]) - s->dither_all = 0; + if (s->dither_flag_syntax) { + for (ch = 1; ch <= fbw_channels; ch++) { + s->dither_flag[ch] = get_bits1(gbc); + } } /* dynamic range */ - i = !(s->channel_mode); + i = !s->channel_mode; do { - if(get_bits1(gbc)) { - s->dynamic_range[i] = ((dynamic_range_tab[get_bits(gbc, 8)]-1.0) * - s->avctx->drc_scale)+1.0; - } else if(blk == 0) { + if (get_bits1(gbc)) { + s->dynamic_range[i] = ((dynamic_range_tab[get_bits(gbc, 8)] - 1.0) * + s->drc_scale) + 1.0; + } else if (blk == 0) { s->dynamic_range[i] = 1.0f; } - } while(i--); + } while (i--); + + /* spectral extension strategy */ + if (s->eac3 && (!blk || get_bits1(gbc))) { + s->spx_in_use = get_bits1(gbc); + if (s->spx_in_use) { + int dst_start_freq, dst_end_freq, src_start_freq, + start_subband, end_subband; + + /* determine which channels use spx */ + if (s->channel_mode == AC3_CHMODE_MONO) { + s->channel_uses_spx[1] = 1; + } else { + for (ch = 1; ch <= fbw_channels; ch++) + s->channel_uses_spx[ch] = get_bits1(gbc); + } + + /* get the frequency bins of the spx copy region and the spx start + and end subbands */ + dst_start_freq = get_bits(gbc, 2); + start_subband = get_bits(gbc, 3) + 2; + if (start_subband > 7) + start_subband += start_subband - 7; + end_subband = get_bits(gbc, 3) + 5; + if (end_subband > 7) + end_subband += end_subband - 7; + dst_start_freq = dst_start_freq * 12 + 25; + src_start_freq = start_subband * 12 + 25; + dst_end_freq = end_subband * 12 + 25; + + /* check validity of spx ranges */ + if (start_subband >= end_subband) { + av_log(s->avctx, AV_LOG_ERROR, "invalid spectral extension " + "range (%d >= %d)\n", start_subband, end_subband); + return -1; + } + if (dst_start_freq >= src_start_freq) { + av_log(s->avctx, AV_LOG_ERROR, "invalid spectral extension " + "copy start bin (%d >= %d)\n", dst_start_freq, src_start_freq); + return -1; + } + + s->spx_dst_start_freq = dst_start_freq; + s->spx_src_start_freq = src_start_freq; + s->spx_dst_end_freq = dst_end_freq; + + decode_band_structure(gbc, blk, s->eac3, 0, + start_subband, end_subband, + ff_eac3_default_spx_band_struct, + &s->num_spx_bands, + s->spx_band_sizes); + } else { + for (ch = 1; ch <= fbw_channels; ch++) { + s->channel_uses_spx[ch] = 0; + s->first_spx_coords[ch] = 1; + } + } + } + + /* spectral extension coordinates */ + if (s->spx_in_use) { + for (ch = 1; ch <= fbw_channels; ch++) { + if (s->channel_uses_spx[ch]) { + if (s->first_spx_coords[ch] || get_bits1(gbc)) { + float spx_blend; + int bin, master_spx_coord; + + s->first_spx_coords[ch] = 0; + spx_blend = get_bits(gbc, 5) * (1.0f/32); + master_spx_coord = get_bits(gbc, 2) * 3; + + bin = s->spx_src_start_freq; + for (bnd = 0; bnd < s->num_spx_bands; bnd++) { + int bandsize; + int spx_coord_exp, spx_coord_mant; + float nratio, sblend, nblend, spx_coord; + + /* calculate blending factors */ + bandsize = s->spx_band_sizes[bnd]; + nratio = ((float)((bin + (bandsize >> 1))) / s->spx_dst_end_freq) - spx_blend; + nratio = av_clipf(nratio, 0.0f, 1.0f); + nblend = sqrtf(3.0f * nratio); // noise is scaled by sqrt(3) + // to give unity variance + sblend = sqrtf(1.0f - nratio); + bin += bandsize; + + /* decode spx coordinates */ + spx_coord_exp = get_bits(gbc, 4); + spx_coord_mant = get_bits(gbc, 2); + if (spx_coord_exp == 15) spx_coord_mant <<= 1; + else spx_coord_mant += 4; + spx_coord_mant <<= (25 - spx_coord_exp - master_spx_coord); + spx_coord = spx_coord_mant * (1.0f / (1 << 23)); + + /* multiply noise and signal blending factors by spx coordinate */ + s->spx_noise_blend [ch][bnd] = nblend * spx_coord; + s->spx_signal_blend[ch][bnd] = sblend * spx_coord; + } + } + } else { + s->first_spx_coords[ch] = 1; + } + } + } /* coupling strategy */ - if (get_bits1(gbc)) { + if (s->eac3 ? s->cpl_strategy_exists[blk] : get_bits1(gbc)) { memset(bit_alloc_stages, 3, AC3_MAX_CHANNELS); - s->cpl_in_use[blk] = get_bits1(gbc); + if (!s->eac3) + s->cpl_in_use[blk] = get_bits1(gbc); if (s->cpl_in_use[blk]) { /* coupling in use */ - int cpl_begin_freq, cpl_end_freq; + int cpl_start_subband, cpl_end_subband; if (channel_mode < AC3_CHMODE_STEREO) { av_log(s->avctx, AV_LOG_ERROR, "coupling not allowed in mono or dual-mono\n"); return -1; } + /* check for enhanced coupling */ + if (s->eac3 && get_bits1(gbc)) { + /* TODO: parse enhanced coupling strategy info */ + av_log_missing_feature(s->avctx, "Enhanced coupling", 1); + return -1; + } + /* determine which channels are coupled */ - for (ch = 1; ch <= fbw_channels; ch++) - s->channel_in_cpl[ch] = get_bits1(gbc); + if (s->eac3 && s->channel_mode == AC3_CHMODE_STEREO) { + s->channel_in_cpl[1] = 1; + s->channel_in_cpl[2] = 1; + } else { + for (ch = 1; ch <= fbw_channels; ch++) + s->channel_in_cpl[ch] = get_bits1(gbc); + } /* phase flags in use */ if (channel_mode == AC3_CHMODE_STEREO) s->phase_flags_in_use = get_bits1(gbc); - /* coupling frequency range and band structure */ - cpl_begin_freq = get_bits(gbc, 4); - cpl_end_freq = get_bits(gbc, 4); - if (3 + cpl_end_freq - cpl_begin_freq < 0) { - av_log(s->avctx, AV_LOG_ERROR, "3+cplendf = %d < cplbegf = %d\n", 3+cpl_end_freq, cpl_begin_freq); + /* coupling frequency range */ + cpl_start_subband = get_bits(gbc, 4); + cpl_end_subband = s->spx_in_use ? (s->spx_src_start_freq - 37) / 12 : + get_bits(gbc, 4) + 3; + if (cpl_start_subband >= cpl_end_subband) { + av_log(s->avctx, AV_LOG_ERROR, "invalid coupling range (%d >= %d)\n", + cpl_start_subband, cpl_end_subband); return -1; } - s->num_cpl_bands = s->num_cpl_subbands = 3 + cpl_end_freq - cpl_begin_freq; - s->start_freq[CPL_CH] = cpl_begin_freq * 12 + 37; - s->end_freq[CPL_CH] = cpl_end_freq * 12 + 73; - for (bnd = 0; bnd < s->num_cpl_subbands - 1; bnd++) { - if (get_bits1(gbc)) { - s->cpl_band_struct[bnd] = 1; - s->num_cpl_bands--; - } - } - s->cpl_band_struct[s->num_cpl_subbands-1] = 0; + s->start_freq[CPL_CH] = cpl_start_subband * 12 + 37; + s->end_freq[CPL_CH] = cpl_end_subband * 12 + 37; + + decode_band_structure(gbc, blk, s->eac3, 0, cpl_start_subband, + cpl_end_subband, + ff_eac3_default_cpl_band_struct, + &s->num_cpl_bands, s->cpl_band_sizes); } else { /* coupling not in use */ - for (ch = 1; ch <= fbw_channels; ch++) + for (ch = 1; ch <= fbw_channels; ch++) { s->channel_in_cpl[ch] = 0; + s->first_cpl_coords[ch] = 1; + } + s->first_cpl_leak = s->eac3; + s->phase_flags_in_use = 0; + } + } else if (!s->eac3) { + if (!blk) { + av_log(s->avctx, AV_LOG_ERROR, "new coupling strategy must " + "be present in block 0\n"); + return -1; + } else { + s->cpl_in_use[blk] = s->cpl_in_use[blk-1]; } - } else if (!blk) { - av_log(s->avctx, AV_LOG_ERROR, "new coupling strategy must be present in block 0\n"); - return -1; - } else { - s->cpl_in_use[blk] = s->cpl_in_use[blk-1]; } cpl_in_use = s->cpl_in_use[blk]; @@ -784,8 +962,9 @@ static int decode_audio_block(AC3DecodeContext *s, int blk) for (ch = 1; ch <= fbw_channels; ch++) { if (s->channel_in_cpl[ch]) { - if (get_bits1(gbc)) { + if ((s->eac3 && s->first_cpl_coords[ch]) || get_bits1(gbc)) { int master_cpl_coord, cpl_coord_exp, cpl_coord_mant; + s->first_cpl_coords[ch] = 0; cpl_coords_exist = 1; master_cpl_coord = 3 * get_bits(gbc, 2); for (bnd = 0; bnd < s->num_cpl_bands; bnd++) { @@ -798,9 +977,13 @@ static int decode_audio_block(AC3DecodeContext *s, int blk) s->cpl_coords[ch][bnd] >>= (cpl_coord_exp + master_cpl_coord); } } else if (!blk) { - av_log(s->avctx, AV_LOG_ERROR, "new coupling coordinates must be present in block 0\n"); + av_log(s->avctx, AV_LOG_ERROR, "new coupling coordinates must " + "be present in block 0\n"); return -1; } + } else { + /* channel not in coupling */ + s->first_cpl_coords[ch] = 1; } } /* phase flags */ @@ -813,24 +996,27 @@ static int decode_audio_block(AC3DecodeContext *s, int blk) /* stereo rematrixing strategy and band structure */ if (channel_mode == AC3_CHMODE_STEREO) { - if (get_bits1(gbc)) { + if ((s->eac3 && !blk) || get_bits1(gbc)) { s->num_rematrixing_bands = 4; - if(cpl_in_use && s->start_freq[CPL_CH] <= 61) + if (cpl_in_use && s->start_freq[CPL_CH] <= 61) { s->num_rematrixing_bands -= 1 + (s->start_freq[CPL_CH] == 37); - for(bnd=0; bndnum_rematrixing_bands; bnd++) + } else if (s->spx_in_use && s->spx_src_start_freq <= 61) { + s->num_rematrixing_bands--; + } + for (bnd = 0; bnd < s->num_rematrixing_bands; bnd++) s->rematrixing_flags[bnd] = get_bits1(gbc); } else if (!blk) { - av_log(s->avctx, AV_LOG_ERROR, "new rematrixing strategy must be present in block 0\n"); - return -1; + av_log(s->avctx, AV_LOG_WARNING, "Warning: " + "new rematrixing strategy not present in block 0\n"); + s->num_rematrixing_bands = 0; } } /* exponent strategies for each channel */ - s->exp_strategy[blk][CPL_CH] = EXP_REUSE; - s->exp_strategy[blk][s->lfe_ch] = EXP_REUSE; for (ch = !cpl_in_use; ch <= s->channels; ch++) { - s->exp_strategy[blk][ch] = get_bits(gbc, 2 - (ch == s->lfe_ch)); - if(s->exp_strategy[blk][ch] != EXP_REUSE) + if (!s->eac3) + s->exp_strategy[blk][ch] = get_bits(gbc, 2 - (ch == s->lfe_ch)); + if (s->exp_strategy[blk][ch] != EXP_REUSE) bit_alloc_stages[ch] = 3; } @@ -842,17 +1028,19 @@ static int decode_audio_block(AC3DecodeContext *s, int blk) int prev = s->end_freq[ch]; if (s->channel_in_cpl[ch]) s->end_freq[ch] = s->start_freq[CPL_CH]; + else if (s->channel_uses_spx[ch]) + s->end_freq[ch] = s->spx_src_start_freq; else { int bandwidth_code = get_bits(gbc, 6); if (bandwidth_code > 60) { - av_log(s->avctx, AV_LOG_ERROR, "bandwidth code = %d > 60", bandwidth_code); + av_log(s->avctx, AV_LOG_ERROR, "bandwidth code = %d > 60\n", bandwidth_code); return -1; } s->end_freq[ch] = bandwidth_code * 3 + 73; } group_size = 3 << (s->exp_strategy[blk][ch] - 1); - s->num_exp_groups[ch] = (s->end_freq[ch]+group_size-4) / group_size; - if(blk > 0 && s->end_freq[ch] != prev) + s->num_exp_groups[ch] = (s->end_freq[ch] + group_size-4) / group_size; + if (blk > 0 && s->end_freq[ch] != prev) memset(bit_alloc_stages, 3, AC3_MAX_CHANNELS); } } @@ -865,56 +1053,107 @@ static int decode_audio_block(AC3DecodeContext *s, int blk) for (ch = !cpl_in_use; ch <= s->channels; ch++) { if (s->exp_strategy[blk][ch] != EXP_REUSE) { s->dexps[ch][0] = get_bits(gbc, 4) << !ch; - decode_exponents(gbc, s->exp_strategy[blk][ch], - s->num_exp_groups[ch], s->dexps[ch][0], - &s->dexps[ch][s->start_freq[ch]+!!ch]); - if(ch != CPL_CH && ch != s->lfe_ch) + if (decode_exponents(gbc, s->exp_strategy[blk][ch], + s->num_exp_groups[ch], s->dexps[ch][0], + &s->dexps[ch][s->start_freq[ch]+!!ch])) { + av_log(s->avctx, AV_LOG_ERROR, "exponent out-of-range\n"); + return -1; + } + if (ch != CPL_CH && ch != s->lfe_ch) skip_bits(gbc, 2); /* skip gainrng */ } } /* bit allocation information */ - if (get_bits1(gbc)) { - s->bit_alloc_params.slow_decay = ff_ac3_slow_decay_tab[get_bits(gbc, 2)] >> s->bit_alloc_params.sr_shift; - s->bit_alloc_params.fast_decay = ff_ac3_fast_decay_tab[get_bits(gbc, 2)] >> s->bit_alloc_params.sr_shift; - s->bit_alloc_params.slow_gain = ff_ac3_slow_gain_tab[get_bits(gbc, 2)]; - s->bit_alloc_params.db_per_bit = ff_ac3_db_per_bit_tab[get_bits(gbc, 2)]; - s->bit_alloc_params.floor = ff_ac3_floor_tab[get_bits(gbc, 3)]; - for(ch=!cpl_in_use; ch<=s->channels; ch++) - bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2); - } else if (!blk) { - av_log(s->avctx, AV_LOG_ERROR, "new bit allocation info must be present in block 0\n"); - return -1; + if (s->bit_allocation_syntax) { + if (get_bits1(gbc)) { + s->bit_alloc_params.slow_decay = ff_ac3_slow_decay_tab[get_bits(gbc, 2)] >> s->bit_alloc_params.sr_shift; + s->bit_alloc_params.fast_decay = ff_ac3_fast_decay_tab[get_bits(gbc, 2)] >> s->bit_alloc_params.sr_shift; + s->bit_alloc_params.slow_gain = ff_ac3_slow_gain_tab[get_bits(gbc, 2)]; + s->bit_alloc_params.db_per_bit = ff_ac3_db_per_bit_tab[get_bits(gbc, 2)]; + s->bit_alloc_params.floor = ff_ac3_floor_tab[get_bits(gbc, 3)]; + for (ch = !cpl_in_use; ch <= s->channels; ch++) + bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2); + } else if (!blk) { + av_log(s->avctx, AV_LOG_ERROR, "new bit allocation info must " + "be present in block 0\n"); + return -1; + } } /* signal-to-noise ratio offsets and fast gains (signal-to-mask ratios) */ - if (get_bits1(gbc)) { - int csnr; - csnr = (get_bits(gbc, 6) - 15) << 4; - for (ch = !cpl_in_use; ch <= s->channels; ch++) { /* snr offset and fast gain */ - s->snr_offset[ch] = (csnr + get_bits(gbc, 4)) << 2; + if (!s->eac3 || !blk) { + if (s->snr_offset_strategy && get_bits1(gbc)) { + int snr = 0; + int csnr; + csnr = (get_bits(gbc, 6) - 15) << 4; + for (i = ch = !cpl_in_use; ch <= s->channels; ch++) { + /* snr offset */ + if (ch == i || s->snr_offset_strategy == 2) + snr = (csnr + get_bits(gbc, 4)) << 2; + /* run at least last bit allocation stage if snr offset changes */ + if (blk && s->snr_offset[ch] != snr) { + bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 1); + } + s->snr_offset[ch] = snr; + + /* fast gain (normal AC-3 only) */ + if (!s->eac3) { + int prev = s->fast_gain[ch]; + s->fast_gain[ch] = ff_ac3_fast_gain_tab[get_bits(gbc, 3)]; + /* run last 2 bit allocation stages if fast gain changes */ + if (blk && prev != s->fast_gain[ch]) + bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2); + } + } + } else if (!s->eac3 && !blk) { + av_log(s->avctx, AV_LOG_ERROR, "new snr offsets must be present in block 0\n"); + return -1; + } + } + + /* fast gain (E-AC-3 only) */ + if (s->fast_gain_syntax && get_bits1(gbc)) { + for (ch = !cpl_in_use; ch <= s->channels; ch++) { + int prev = s->fast_gain[ch]; s->fast_gain[ch] = ff_ac3_fast_gain_tab[get_bits(gbc, 3)]; + /* run last 2 bit allocation stages if fast gain changes */ + if (blk && prev != s->fast_gain[ch]) + bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2); } - memset(bit_alloc_stages, 3, AC3_MAX_CHANNELS); - } else if (!blk) { - av_log(s->avctx, AV_LOG_ERROR, "new snr offsets must be present in block 0\n"); - return -1; + } else if (s->eac3 && !blk) { + for (ch = !cpl_in_use; ch <= s->channels; ch++) + s->fast_gain[ch] = ff_ac3_fast_gain_tab[4]; + } + + /* E-AC-3 to AC-3 converter SNR offset */ + if (s->frame_type == EAC3_FRAME_TYPE_INDEPENDENT && get_bits1(gbc)) { + skip_bits(gbc, 10); // skip converter snr offset } /* coupling leak information */ if (cpl_in_use) { - if (get_bits1(gbc)) { - s->bit_alloc_params.cpl_fast_leak = get_bits(gbc, 3); - s->bit_alloc_params.cpl_slow_leak = get_bits(gbc, 3); - bit_alloc_stages[CPL_CH] = FFMAX(bit_alloc_stages[CPL_CH], 2); - } else if (!blk) { - av_log(s->avctx, AV_LOG_ERROR, "new coupling leak info must be present in block 0\n"); + if (s->first_cpl_leak || get_bits1(gbc)) { + int fl = get_bits(gbc, 3); + int sl = get_bits(gbc, 3); + /* run last 2 bit allocation stages for coupling channel if + coupling leak changes */ + if (blk && (fl != s->bit_alloc_params.cpl_fast_leak || + sl != s->bit_alloc_params.cpl_slow_leak)) { + bit_alloc_stages[CPL_CH] = FFMAX(bit_alloc_stages[CPL_CH], 2); + } + s->bit_alloc_params.cpl_fast_leak = fl; + s->bit_alloc_params.cpl_slow_leak = sl; + } else if (!s->eac3 && !blk) { + av_log(s->avctx, AV_LOG_ERROR, "new coupling leak info must " + "be present in block 0\n"); return -1; } + s->first_cpl_leak = 0; } /* delta bit allocation information */ - if (get_bits1(gbc)) { + if (s->dba_syntax && get_bits1(gbc)) { /* delta bit allocation exists (strategy) */ for (ch = !cpl_in_use; ch <= fbw_channels; ch++) { s->dba_mode[ch] = get_bits(gbc, 2); @@ -927,74 +1166,87 @@ static int decode_audio_block(AC3DecodeContext *s, int blk) /* channel delta offset, len and bit allocation */ for (ch = !cpl_in_use; ch <= fbw_channels; ch++) { if (s->dba_mode[ch] == DBA_NEW) { - s->dba_nsegs[ch] = get_bits(gbc, 3); - for (seg = 0; seg <= s->dba_nsegs[ch]; seg++) { + s->dba_nsegs[ch] = get_bits(gbc, 3) + 1; + for (seg = 0; seg < s->dba_nsegs[ch]; seg++) { s->dba_offsets[ch][seg] = get_bits(gbc, 5); s->dba_lengths[ch][seg] = get_bits(gbc, 4); - s->dba_values[ch][seg] = get_bits(gbc, 3); + s->dba_values[ch][seg] = get_bits(gbc, 3); } /* run last 2 bit allocation stages if new dba values */ bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2); } } - } else if(blk == 0) { - for(ch=0; ch<=s->channels; ch++) { + } else if (blk == 0) { + for (ch = 0; ch <= s->channels; ch++) { s->dba_mode[ch] = DBA_NONE; } } /* Bit allocation */ - for(ch=!cpl_in_use; ch<=s->channels; ch++) { - if(bit_alloc_stages[ch] > 2) { + for (ch = !cpl_in_use; ch <= s->channels; ch++) { + if (bit_alloc_stages[ch] > 2) { /* Exponent mapping into PSD and PSD integration */ ff_ac3_bit_alloc_calc_psd(s->dexps[ch], s->start_freq[ch], s->end_freq[ch], s->psd[ch], s->band_psd[ch]); } - if(bit_alloc_stages[ch] > 1) { + if (bit_alloc_stages[ch] > 1) { /* Compute excitation function, Compute masking curve, and Apply delta bit allocation */ - ff_ac3_bit_alloc_calc_mask(&s->bit_alloc_params, s->band_psd[ch], - s->start_freq[ch], s->end_freq[ch], - s->fast_gain[ch], (ch == s->lfe_ch), - s->dba_mode[ch], s->dba_nsegs[ch], - s->dba_offsets[ch], s->dba_lengths[ch], - s->dba_values[ch], s->mask[ch]); + if (ff_ac3_bit_alloc_calc_mask(&s->bit_alloc_params, s->band_psd[ch], + s->start_freq[ch], s->end_freq[ch], + s->fast_gain[ch], (ch == s->lfe_ch), + s->dba_mode[ch], s->dba_nsegs[ch], + s->dba_offsets[ch], s->dba_lengths[ch], + s->dba_values[ch], s->mask[ch])) { + av_log(s->avctx, AV_LOG_ERROR, "error in bit allocation\n"); + return -1; + } } - if(bit_alloc_stages[ch] > 0) { + if (bit_alloc_stages[ch] > 0) { /* Compute bit allocation */ - ff_ac3_bit_alloc_calc_bap(s->mask[ch], s->psd[ch], + const uint8_t *bap_tab = s->channel_uses_aht[ch] ? + ff_eac3_hebap_tab : ff_ac3_bap_tab; + s->ac3dsp.bit_alloc_calc_bap(s->mask[ch], s->psd[ch], s->start_freq[ch], s->end_freq[ch], s->snr_offset[ch], s->bit_alloc_params.floor, - ff_ac3_bap_tab, s->bap[ch]); + bap_tab, s->bap[ch]); } } /* unused dummy data */ - if (get_bits1(gbc)) { + if (s->skip_syntax && get_bits1(gbc)) { int skipl = get_bits(gbc, 9); - while(skipl--) + while (skipl--) skip_bits(gbc, 8); } /* unpack the transform coefficients this also uncouples channels if coupling is in use. */ - get_transform_coeffs(s); + decode_transform_coeffs(s, blk); + + /* TODO: generate enhanced coupling coordinates and uncouple */ /* recover coefficients if rematrixing is in use */ - if(s->channel_mode == AC3_CHMODE_STEREO) + if (s->channel_mode == AC3_CHMODE_STEREO) do_rematrixing(s); /* apply scaling to coefficients (headroom, dynrng) */ - for(ch=1; ch<=s->channels; ch++) { + for (ch = 1; ch <= s->channels; ch++) { float gain = s->mul_bias / 4194304.0f; - if(s->channel_mode == AC3_CHMODE_DUALMONO) { - gain *= s->dynamic_range[ch-1]; + if (s->channel_mode == AC3_CHMODE_DUALMONO) { + gain *= s->dynamic_range[2 - ch]; } else { gain *= s->dynamic_range[0]; } - s->dsp.int32_to_float_fmul_scalar(s->transform_coeffs[ch], s->fixed_coeffs[ch], gain, 256); + s->fmt_conv.int32_to_float_fmul_scalar(s->transform_coeffs[ch], + s->fixed_coeffs[ch], gain, 256); + } + + /* apply spectral extension to high frequency bins */ + if (s->spx_in_use && CONFIG_EAC3_DECODER) { + ff_eac3_apply_spectral_extension(s); } /* downmix and MDCT. order depends on whether block switching is used for @@ -1003,27 +1255,30 @@ static int decode_audio_block(AC3DecodeContext *s, int blk) downmix_output = s->channels != s->out_channels && !((s->output_mode & AC3_OUTPUT_LFEON) && s->fbw_channels == s->out_channels); - if(different_transforms) { + if (different_transforms) { /* the delay samples have already been downmixed, so we upmix the delay samples in order to reconstruct all channels before downmixing. */ - if(s->downmixed) { + if (s->downmixed) { s->downmixed = 0; ac3_upmix_delay(s); } do_imdct(s, s->channels); - if(downmix_output) { - s->dsp.ac3_downmix(s->output, s->downmix_coeffs, s->out_channels, s->fbw_channels, 256); + if (downmix_output) { + s->dsp.ac3_downmix(s->output, s->downmix_coeffs, + s->out_channels, s->fbw_channels, 256); } } else { - if(downmix_output) { - s->dsp.ac3_downmix(s->transform_coeffs+1, s->downmix_coeffs, s->out_channels, s->fbw_channels, 256); + if (downmix_output) { + s->dsp.ac3_downmix(s->transform_coeffs + 1, s->downmix_coeffs, + s->out_channels, s->fbw_channels, 256); } - if(downmix_output && !s->downmixed) { + if (downmix_output && !s->downmixed) { s->downmixed = 1; - s->dsp.ac3_downmix(s->delay, s->downmix_coeffs, s->out_channels, s->fbw_channels, 128); + s->dsp.ac3_downmix(s->delay, s->downmix_coeffs, s->out_channels, + s->fbw_channels, 128); } do_imdct(s, s->out_channels); @@ -1035,112 +1290,145 @@ static int decode_audio_block(AC3DecodeContext *s, int blk) /** * Decode a single AC-3 frame. */ -static int ac3_decode_frame(AVCodecContext * avctx, void *data, int *data_size, - const uint8_t *buf, int buf_size) +static int ac3_decode_frame(AVCodecContext * avctx, void *data, + int *got_frame_ptr, AVPacket *avpkt) { + const uint8_t *buf = avpkt->data; + int buf_size = avpkt->size; AC3DecodeContext *s = avctx->priv_data; - int16_t *out_samples = (int16_t *)data; - int blk, ch, err; - + float *out_samples_flt; + int16_t *out_samples_s16; + int blk, ch, err, ret; + const uint8_t *channel_map; + const float *output[AC3_MAX_CHANNELS]; + + /* copy input buffer to decoder context to avoid reading past the end + of the buffer, which can be caused by a damaged input stream. */ + if (buf_size >= 2 && AV_RB16(buf) == 0x770B) { + // seems to be byte-swapped AC-3 + int cnt = FFMIN(buf_size, AC3_FRAME_BUFFER_SIZE) >> 1; + s->dsp.bswap16_buf((uint16_t *)s->input_buffer, (const uint16_t *)buf, cnt); + } else + memcpy(s->input_buffer, buf, FFMIN(buf_size, AC3_FRAME_BUFFER_SIZE)); + buf = s->input_buffer; /* initialize the GetBitContext with the start of valid AC-3 Frame */ - if (s->input_buffer) { - /* copy input buffer to decoder context to avoid reading past the end - of the buffer, which can be caused by a damaged input stream. */ - memcpy(s->input_buffer, buf, FFMIN(buf_size, AC3_MAX_FRAME_SIZE)); - init_get_bits(&s->gbc, s->input_buffer, buf_size * 8); - } else { - init_get_bits(&s->gbc, buf, buf_size * 8); - } + init_get_bits(&s->gbc, buf, buf_size * 8); /* parse the syncinfo */ - *data_size = 0; err = parse_frame_header(s); - /* check that reported frame size fits in input buffer */ - if(s->frame_size > buf_size) { - av_log(avctx, AV_LOG_ERROR, "incomplete frame\n"); - err = AC3_PARSE_ERROR_FRAME_SIZE; - } - - /* check for crc mismatch */ - if(err != AC3_PARSE_ERROR_FRAME_SIZE && avctx->error_resilience >= FF_ER_CAREFUL) { - if(av_crc(av_crc_get_table(AV_CRC_16_ANSI), 0, &buf[2], s->frame_size-2)) { - av_log(avctx, AV_LOG_ERROR, "frame CRC mismatch\n"); - err = AC3_PARSE_ERROR_CRC; + if (err) { + switch (err) { + case AAC_AC3_PARSE_ERROR_SYNC: + av_log(avctx, AV_LOG_ERROR, "frame sync error\n"); + return -1; + case AAC_AC3_PARSE_ERROR_BSID: + av_log(avctx, AV_LOG_ERROR, "invalid bitstream id\n"); + break; + case AAC_AC3_PARSE_ERROR_SAMPLE_RATE: + av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n"); + break; + case AAC_AC3_PARSE_ERROR_FRAME_SIZE: + av_log(avctx, AV_LOG_ERROR, "invalid frame size\n"); + break; + case AAC_AC3_PARSE_ERROR_FRAME_TYPE: + /* skip frame if CRC is ok. otherwise use error concealment. */ + /* TODO: add support for substreams and dependent frames */ + if (s->frame_type == EAC3_FRAME_TYPE_DEPENDENT || s->substreamid) { + av_log(avctx, AV_LOG_ERROR, "unsupported frame type : " + "skipping frame\n"); + *got_frame_ptr = 0; + return s->frame_size; + } else { + av_log(avctx, AV_LOG_ERROR, "invalid frame type\n"); + } + break; + default: + av_log(avctx, AV_LOG_ERROR, "invalid header\n"); + break; } - } - - if(err && err != AC3_PARSE_ERROR_CRC) { - switch(err) { - case AC3_PARSE_ERROR_SYNC: - av_log(avctx, AV_LOG_ERROR, "frame sync error\n"); - return -1; - case AC3_PARSE_ERROR_BSID: - av_log(avctx, AV_LOG_ERROR, "invalid bitstream id\n"); - break; - case AC3_PARSE_ERROR_SAMPLE_RATE: - av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n"); - break; - case AC3_PARSE_ERROR_FRAME_SIZE: - av_log(avctx, AV_LOG_ERROR, "invalid frame size\n"); - break; - case AC3_PARSE_ERROR_FRAME_TYPE: - /* skip frame if CRC is ok. otherwise use error concealment. */ - /* TODO: add support for substreams and dependent frames */ - if(s->frame_type == EAC3_FRAME_TYPE_DEPENDENT || s->substreamid) { - av_log(avctx, AV_LOG_ERROR, "unsupported frame type : skipping frame\n"); - return s->frame_size; - } else { - av_log(avctx, AV_LOG_ERROR, "invalid frame type\n"); - } - break; - default: - av_log(avctx, AV_LOG_ERROR, "invalid header\n"); - break; + } else { + /* check that reported frame size fits in input buffer */ + if (s->frame_size > buf_size) { + av_log(avctx, AV_LOG_ERROR, "incomplete frame\n"); + err = AAC_AC3_PARSE_ERROR_FRAME_SIZE; + } else if (avctx->err_recognition & AV_EF_CRCCHECK) { + /* check for crc mismatch */ + if (av_crc(av_crc_get_table(AV_CRC_16_ANSI), 0, &buf[2], + s->frame_size - 2)) { + av_log(avctx, AV_LOG_ERROR, "frame CRC mismatch\n"); + err = AAC_AC3_PARSE_ERROR_CRC; + } } } /* if frame is ok, set audio parameters */ if (!err) { avctx->sample_rate = s->sample_rate; - avctx->bit_rate = s->bit_rate; + avctx->bit_rate = s->bit_rate; /* channel config */ s->out_channels = s->channels; - s->output_mode = s->channel_mode; - if(s->lfe_on) + s->output_mode = s->channel_mode; + if (s->lfe_on) s->output_mode |= AC3_OUTPUT_LFEON; if (avctx->request_channels > 0 && avctx->request_channels <= 2 && avctx->request_channels < s->channels) { s->out_channels = avctx->request_channels; s->output_mode = avctx->request_channels == 1 ? AC3_CHMODE_MONO : AC3_CHMODE_STEREO; + s->channel_layout = avpriv_ac3_channel_layout_tab[s->output_mode]; } - avctx->channels = s->out_channels; + avctx->channels = s->out_channels; + avctx->channel_layout = s->channel_layout; /* set downmixing coefficients if needed */ - if(s->channels != s->out_channels && !((s->output_mode & AC3_OUTPUT_LFEON) && + if (s->channels != s->out_channels && !((s->output_mode & AC3_OUTPUT_LFEON) && s->fbw_channels == s->out_channels)) { set_downmix_coeffs(s); } } else if (!s->out_channels) { s->out_channels = avctx->channels; - if(s->out_channels < s->channels) + if (s->out_channels < s->channels) s->output_mode = s->out_channels == 1 ? AC3_CHMODE_MONO : AC3_CHMODE_STEREO; } + /* set audio service type based on bitstream mode for AC-3 */ + avctx->audio_service_type = s->bitstream_mode; + if (s->bitstream_mode == 0x7 && s->channels > 1) + avctx->audio_service_type = AV_AUDIO_SERVICE_TYPE_KARAOKE; + + /* get output buffer */ + s->frame.nb_samples = s->num_blocks * 256; + if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) { + av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); + return ret; + } + out_samples_flt = (float *)s->frame.data[0]; + out_samples_s16 = (int16_t *)s->frame.data[0]; /* decode the audio blocks */ + channel_map = ff_ac3_dec_channel_map[s->output_mode & ~AC3_OUTPUT_LFEON][s->lfe_on]; + for (ch = 0; ch < s->out_channels; ch++) + output[ch] = s->output[channel_map[ch]]; for (blk = 0; blk < s->num_blocks; blk++) { - const float *output[s->out_channels]; if (!err && decode_audio_block(s, blk)) { av_log(avctx, AV_LOG_ERROR, "error decoding the audio block\n"); + err = 1; + } + if (avctx->sample_fmt == AV_SAMPLE_FMT_FLT) { + s->fmt_conv.float_interleave(out_samples_flt, output, 256, + s->out_channels); + out_samples_flt += 256 * s->out_channels; + } else { + s->fmt_conv.float_to_int16_interleave(out_samples_s16, output, 256, + s->out_channels); + out_samples_s16 += 256 * s->out_channels; } - for (ch = 0; ch < s->out_channels; ch++) - output[ch] = s->output[ch]; - s->dsp.float_to_int16_interleave(out_samples, output, 256, s->out_channels); - out_samples += 256 * s->out_channels; } - *data_size = s->num_blocks * 256 * avctx->channels * sizeof (int16_t); - return s->frame_size; + + *got_frame_ptr = 1; + *(AVFrame *)data = s->frame; + + return FFMIN(buf_size, s->frame_size); } /** @@ -1152,18 +1440,60 @@ static av_cold int ac3_decode_end(AVCodecContext *avctx) ff_mdct_end(&s->imdct_512); ff_mdct_end(&s->imdct_256); - av_freep(&s->input_buffer); - return 0; } -AVCodec ac3_decoder = { - .name = "ac3", - .type = CODEC_TYPE_AUDIO, - .id = CODEC_ID_AC3, +#define OFFSET(x) offsetof(AC3DecodeContext, x) +#define PAR (AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_AUDIO_PARAM) +static const AVOption options[] = { + { "drc_scale", "percentage of dynamic range compression to apply", OFFSET(drc_scale), AV_OPT_TYPE_FLOAT, {1.0}, 0.0, 1.0, PAR }, + { NULL}, +}; + +static const AVClass ac3_decoder_class = { + .class_name = "AC3 decoder", + .item_name = av_default_item_name, + .option = options, + .version = LIBAVUTIL_VERSION_INT, +}; + +AVCodec ff_ac3_decoder = { + .name = "ac3", + .type = AVMEDIA_TYPE_AUDIO, + .id = CODEC_ID_AC3, + .priv_data_size = sizeof (AC3DecodeContext), + .init = ac3_decode_init, + .close = ac3_decode_end, + .decode = ac3_decode_frame, + .capabilities = CODEC_CAP_DR1, + .long_name = NULL_IF_CONFIG_SMALL("ATSC A/52A (AC-3)"), + .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLT, + AV_SAMPLE_FMT_S16, + AV_SAMPLE_FMT_NONE }, + .priv_class = &ac3_decoder_class, +}; + +#if CONFIG_EAC3_DECODER +static const AVClass eac3_decoder_class = { + .class_name = "E-AC3 decoder", + .item_name = av_default_item_name, + .option = options, + .version = LIBAVUTIL_VERSION_INT, +}; + +AVCodec ff_eac3_decoder = { + .name = "eac3", + .type = AVMEDIA_TYPE_AUDIO, + .id = CODEC_ID_EAC3, .priv_data_size = sizeof (AC3DecodeContext), - .init = ac3_decode_init, - .close = ac3_decode_end, - .decode = ac3_decode_frame, - .long_name = NULL_IF_CONFIG_SMALL("ATSC A/52 / AC-3"), + .init = ac3_decode_init, + .close = ac3_decode_end, + .decode = ac3_decode_frame, + .capabilities = CODEC_CAP_DR1, + .long_name = NULL_IF_CONFIG_SMALL("ATSC A/52B (AC-3, E-AC-3)"), + .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLT, + AV_SAMPLE_FMT_S16, + AV_SAMPLE_FMT_NONE }, + .priv_class = &eac3_decoder_class, }; +#endif