* 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 <bartek.wolowiec@gmail.com>
* Copyright (c) 2007 Justin Ruggles <justin.ruggles@gmail.com>
*
- * Portions of this code are derived from liba52
- * http://liba52.sourceforge.net
- * Copyright (C) 2000-2003 Michel Lespinasse <walken@zoy.org>
- * Copyright (C) 1999-2000 Aaron Holtzman <aholtzma@ess.engr.uvic.ca>
- *
* 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
*/
#include <string.h>
#include "libavutil/crc.h"
+#include "internal.h"
+#include "aac_ac3_parser.h"
#include "ac3_parser.h"
#include "ac3dec.h"
#include "ac3dec_data.h"
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);
+ 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;
- s->mul_bias = 1.0f;
- } else {
- s->add_bias = 0.0f;
- s->mul_bias = 32767.0f;
- }
+ /* set scale value for float to int16 conversion */
+ s->mul_bias = 32767.0f;
/* allow downmixing to stereo or mono */
if (avctx->channels > 0 && avctx->request_channels > 0 &&
s->downmixed = 1;
/* allocate context input buffer */
- if (avctx->error_resilience >= FF_ER_CAREFUL) {
+ if (avctx->error_recognition >= FF_ER_CAREFUL) {
s->input_buffer = av_mallocz(AC3_FRAME_BUFFER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);
if (!s->input_buffer)
- return AVERROR_NOMEM;
+ return AVERROR(ENOMEM);
}
- avctx->sample_fmt = SAMPLE_FMT_S16;
+ avctx->sample_fmt = AV_SAMPLE_FMT_S16;
return 0;
}
/* get decoding parameters from header info */
s->bit_alloc_params.sr_code = hdr.sr_code;
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;
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 {
- /*s->eac3 = 1;
- return ff_eac3_parse_header(s);*/
- return AC3_PARSE_ERROR_BSID;
+ av_log(s->avctx, AV_LOG_ERROR, "E-AC-3 support not compiled in\n");
+ return -1;
}
}
* 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];
/* convert to absolute exps and expand groups */
prevexp = absexp;
- for(i=0; i<ngrps*3; i++) {
- prevexp = av_clip(prevexp + dexp[i]-2, 0, 24);
- for(j=0; j<group_size; j++) {
- dexps[(i*group_size)+j] = prevexp;
+ for(i=0,j=0; i<ngrps*3; i++) {
+ prevexp += dexp[i] - 2;
+ if (prevexp > 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;
}
/**
*/
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; bnd<s->num_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;
}
}
* 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) {
+ 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; i<end; i++) {
- if(!bap[i])
- coeffs[i] = 0;
- }
- if(s->channel_in_cpl[ch]) {
- bap = s->bap[CPL_CH];
- for(; i<s->end_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]; i<s->end_freq[CPL_CH]; i++) {
+ if(!s->bap[CPL_CH][i])
+ s->fixed_coeffs[ch][i] = 0;
}
}
}
}
-#if 0
-static void get_transform_coeffs_ch(AC3DecodeContext *s, int blk, int ch,
+static void decode_transform_coeffs_ch(AC3DecodeContext *s, int blk, int ch,
mant_groups *m)
{
if (!s->channel_uses_aht[ch]) {
- ac3_get_transform_coeffs_ch(s, ch, m);
+ 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)
- ff_eac3_get_transform_coeffs_aht_ch(s, ch);
+ 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];
}
}
}
-#endif
/**
- * 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;
}
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);
}
/**
{
int bnd, i;
int end, bndend;
- int tmp0, tmp1;
end = FFMIN(s->end_freq[1], s->end_freq[2]);
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++) {
- tmp0 = s->fixed_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];
}
}
}
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++) {
if (s->block_switch[ch]) {
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);
+ 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];
ff_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);
+ 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));
}
}
}
}
+/**
+ * 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.
*/
/* dithering flags */
if (s->dither_flag_syntax) {
- 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;
}
}
/* spectral extension strategy */
if (s->eac3 && (!blk || get_bits1(gbc))) {
- if (get_bits1(gbc)) {
- av_log_missing_feature(s->avctx, "Spectral extension", 1);
- return -1;
+ 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;
+ }
}
- /* TODO: parse spectral extension strategy info */
}
- /* TODO: spectral extension coordinates */
+ /* 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);
if (!s->eac3)
- s->cpl_in_use[blk] = get_bits1(gbc);
+ 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");
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);
+ for (ch = 1; ch <= fbw_channels; ch++)
+ s->channel_in_cpl[ch] = get_bits1(gbc);
}
/* phase flags in use */
s->phase_flags_in_use = get_bits1(gbc);
/* coupling frequency range */
- /* TODO: modify coupling end freq if spectral extension is used */
- 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);
+ 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;
-
- /* coupling band structure */
- if (!s->eac3 || get_bits1(gbc)) {
- for (bnd = 0; bnd < s->num_cpl_subbands - 1; bnd++) {
- s->cpl_band_struct[bnd] = get_bits1(gbc);
- }
- } else if (!blk) {
- }
- 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;
- /* calculate number of coupling bands based on band structure */
- for (bnd = 0; bnd < s->num_cpl_subbands-1; bnd++) {
- s->num_cpl_bands -= s->cpl_band_struct[bnd];
- }
+ 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++) {
s->channel_in_cpl[ch] = 0;
s->first_cpl_coords[ch] = 1;
}
- s->first_cpl_leak = 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];
- }
+ 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];
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++) {
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 */
if (channel_mode == AC3_CHMODE_STEREO) {
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);
+ } 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->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;
}
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;
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 (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 */
}
}
/* 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;
- s->fast_gain[ch] = ff_ac3_fast_gain_tab[get_bits(gbc, 3)];
+ 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;
}
- 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;
}
/* fast gain (E-AC-3 only) */
/* 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) {
+ 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(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) {
/* Compute bit allocation */
/* 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 */
- /* TODO: apply spectral extension */
-
/* recover coefficients if rematrixing is in use */
if(s->channel_mode == AC3_CHMODE_STEREO)
do_rematrixing(s);
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];
}
- 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
* 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)
+ 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;
+ 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) {
*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 && err != AC3_PARSE_ERROR_CRC) {
+ if (err) {
switch(err) {
- case AC3_PARSE_ERROR_SYNC:
+ case AAC_AC3_PARSE_ERROR_SYNC:
av_log(avctx, AV_LOG_ERROR, "frame sync error\n");
return -1;
- case AC3_PARSE_ERROR_BSID:
+ case AAC_AC3_PARSE_ERROR_BSID:
av_log(avctx, AV_LOG_ERROR, "invalid bitstream id\n");
break;
- case AC3_PARSE_ERROR_SAMPLE_RATE:
+ case AAC_AC3_PARSE_ERROR_SAMPLE_RATE:
av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n");
break;
- case AC3_PARSE_ERROR_FRAME_SIZE:
+ case AAC_AC3_PARSE_ERROR_FRAME_SIZE:
av_log(avctx, AV_LOG_ERROR, "invalid frame size\n");
break;
- case AC3_PARSE_ERROR_FRAME_TYPE:
+ 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, "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->error_recognition >= FF_ER_CAREFUL) {
+ /* 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 */
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 = ff_ac3_channel_layout_tab[s->output_mode];
}
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) &&
}
/* 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[ch];
- s->dsp.float_to_int16_interleave(out_samples, output, 256, s->out_channels);
+ s->fmt_conv.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;
+ return FFMIN(buf_size, s->frame_size);
}
/**
return 0;
}
-AVCodec ac3_decoder = {
+AVCodec ff_ac3_decoder = {
.name = "ac3",
- .type = CODEC_TYPE_AUDIO,
+ .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,
- .long_name = NULL_IF_CONFIG_SMALL("ATSC A/52 (AC-3, E-AC-3)"),
+ .long_name = NULL_IF_CONFIG_SMALL("ATSC A/52A (AC-3)"),
};
+
+#if CONFIG_EAC3_DECODER
+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/52B (AC-3, E-AC-3)"),
+};
+#endif