X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fac3dec.c;h=82091bc6e3f4f52fcc70d7410fcbf70e1322c47f;hb=43a6ca2c3d2fd3ebd262e08b249e57d6f0902aba;hp=c142ca9bb21a5109c036103282edd83579de2252;hpb=bfeca7beb63bc297c8c59469a53e469d11ec4d23;p=ffmpeg diff --git a/libavcodec/ac3dec.c b/libavcodec/ac3dec.c index c142ca9bb21..82091bc6e3f 100644 --- a/libavcodec/ac3dec.c +++ b/libavcodec/ac3dec.c @@ -7,24 +7,19 @@ * 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 FFmpeg. * * FFmpeg is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public + * 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, * 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 + * 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 */ @@ -194,8 +189,8 @@ static av_cold int ac3_decode_init(AVCodecContext *avctx) 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_lfg_init(&s->dith_state, 0); @@ -319,9 +314,12 @@ static int parse_frame_header(AC3DecodeContext *s) s->skip_syntax = 1; memset(s->channel_uses_aht, 0, sizeof(s->channel_uses_aht)); return ac3_parse_header(s); - } else { + } 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; } } @@ -414,24 +412,26 @@ static int 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]) { + int64_t cpl_coord = s->cpl_coords[ch][band]; + for (bin = band_start; bin < band_end; bin++) { + s->fixed_coeffs[ch][bin] = ((int64_t)s->fixed_coeffs[CPL_CH][bin] * + cpl_coord) >> 23; + } + 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; } } @@ -439,12 +439,12 @@ 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; /** @@ -453,104 +453,92 @@ typedef struct { */ 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) { + int freq; + + for(freq = start_freq; freq < end_freq; freq++){ + int bap = baps[freq]; + int mantissa; + switch(bap){ case 0: - coeffs[i] = (av_lfg_get(&s->dith_state) & 0x7FFFFF) - 0x400000; + if (dither) + mantissa = (av_lfg_get(&s->dith_state) & 0x7FFFFF) - 0x400000; + else + mantissa = 0; 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; + 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; } - 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; + 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; } - coeffs[i] = m->b2_mant[m->b2ptr++]; break; - case 3: - coeffs[i] = b3_mantissas[get_bits(gbc, 3)]; + mantissa = 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; + 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; } - coeffs[i] = m->b4_mant[m->b4ptr++]; break; - case 5: - coeffs[i] = b5_mantissas[get_bits(gbc, 4)]; + mantissa = b5_mantissas[get_bits(gbc, 4)]; break; - - default: { - /* asymmetric dequantization */ - int qlevel = quantization_tab[tbap]; - coeffs[i] = get_sbits(gbc, qlevel) << (24 - qlevel); + default: /* 6 to 15 */ + mantissa = get_bits(gbc, quantization_tab[bap]); + /* Shift mantissa and sign-extend it. */ + mantissa = (mantissa << (32-quantization_tab[bap]))>>8; 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; - } + if(!s->dither_flag[ch] && s->channel_in_cpl[ch]) { + for(i = s->start_freq[CPL_CH]; iend_freq[CPL_CH]; i++) { + if(!s->bap[CPL_CH][i]) + s->fixed_coeffs[ch][i] = 0; } } } @@ -565,7 +553,7 @@ static void decode_transform_coeffs_ch(AC3DecodeContext *s, int blk, int ch, /* if AHT is used, mantissas for all blocks are encoded in the first block of the frame. */ int bin; - if (!blk) + 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]; @@ -582,7 +570,7 @@ static void decode_transform_coeffs(AC3DecodeContext *s, int blk) 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 */ @@ -616,7 +604,6 @@ 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]); @@ -624,10 +611,9 @@ static void do_rematrixing(AC3DecodeContext *s) 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; + 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]; } } } @@ -721,6 +707,10 @@ static void ac3_upmix_delay(AC3DecodeContext *s) /** * 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 @@ -728,33 +718,33 @@ static void ac3_upmix_delay(AC3DecodeContext *s) * @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] band_struct decoded band structure - * @param[out] num_subbands number of subbands (optionally NULL) * @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, - uint8_t *band_struct, int *num_subbands, 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++) { - band_struct[subbnd] = get_bits1(gbc); + coded_band_struct[subbnd] = get_bits1(gbc); } + band_struct = coded_band_struct; } else if (!blk) { - memcpy(band_struct, - &default_band_struct[start_subband+1], - n_subbands-1); + band_struct = &default_band_struct[start_subband+1]; + } else { + /* no change in band structure */ + return; } - band_struct[n_subbands-1] = 0; /* calculate number of bands and band sizes based on band structure. note that the first 4 subbands in enhanced coupling span only 6 bins @@ -774,8 +764,6 @@ static void decode_band_structure(GetBitContext *gbc, int blk, int eac3, } /* set optional output params */ - if (num_subbands) - *num_subbands = n_subbands; if (num_bands) *num_bands = n_bands; if (band_sizes) @@ -829,7 +817,7 @@ static int decode_audio_block(AC3DecodeContext *s, int blk) /* spectral extension strategy */ if (s->eac3 && (!blk || get_bits1(gbc))) { if (get_bits1(gbc)) { - ff_log_missing_feature(s->avctx, "Spectral extension", 1); + av_log_missing_feature(s->avctx, "Spectral extension", 1); return -1; } /* TODO: parse spectral extension strategy info */ @@ -854,7 +842,7 @@ static int decode_audio_block(AC3DecodeContext *s, int blk) /* check for enhanced coupling */ if (s->eac3 && get_bits1(gbc)) { /* TODO: parse enhanced coupling strategy info */ - ff_log_missing_feature(s->avctx, "Enhanced coupling", 1); + av_log_missing_feature(s->avctx, "Enhanced coupling", 1); return -1; } @@ -875,20 +863,18 @@ static int decode_audio_block(AC3DecodeContext *s, int blk) /* TODO: modify coupling end freq if spectral extension is used */ cpl_start_subband = get_bits(gbc, 4); cpl_end_subband = get_bits(gbc, 4) + 3; - s->num_cpl_subbands = cpl_end_subband - cpl_start_subband; - if (s->num_cpl_subbands < 0) { - av_log(s->avctx, AV_LOG_ERROR, "invalid coupling range (%d > %d)\n", + 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->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->cpl_band_struct, &s->num_cpl_subbands, - &s->num_cpl_bands, NULL); + 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++) { @@ -954,8 +940,8 @@ static int decode_audio_block(AC3DecodeContext *s, int blk) for(bnd=0; bndnum_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; } } @@ -1181,7 +1167,7 @@ static int decode_audio_block(AC3DecodeContext *s, int blk) 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]; + gain *= s->dynamic_range[2-ch]; } else { gain *= s->dynamic_range[0]; } @@ -1235,6 +1221,7 @@ static int ac3_decode_frame(AVCodecContext * avctx, void *data, int *data_size, int16_t *out_samples = (int16_t *)data; int blk, ch, err; const uint8_t *channel_map; + const float *output[AC3_MAX_CHANNELS]; /* initialize the GetBitContext with the start of valid AC-3 Frame */ if (s->input_buffer) { @@ -1326,14 +1313,13 @@ static int ac3_decode_frame(AVCodecContext * avctx, void *data, int *data_size, /* 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; } - for (ch = 0; ch < s->out_channels; ch++) - output[ch] = s->output[channel_map[ch]]; s->dsp.float_to_int16_interleave(out_samples, output, 256, s->out_channels); out_samples += 256 * s->out_channels; } @@ -1366,6 +1352,7 @@ AVCodec ac3_decoder = { .long_name = NULL_IF_CONFIG_SMALL("ATSC A/52A (AC-3)"), }; +#if CONFIG_EAC3_DECODER AVCodec eac3_decoder = { .name = "eac3", .type = CODEC_TYPE_AUDIO, @@ -1376,3 +1363,4 @@ AVCodec eac3_decoder = { .decode = ac3_decode_frame, .long_name = NULL_IF_CONFIG_SMALL("ATSC A/52B (AC-3, E-AC-3)"), }; +#endif