* Copyright (c) 2007 Bartlomiej Wolowiec <bartek.wolowiec@gmail.com>
* Copyright (c) 2008 Justin Ruggles
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * 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 2.1 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
+/*
+ * There are several features of E-AC-3 that this decoder does not yet support.
+ *
+ * Enhanced Coupling
+ * No known samples exist. If any ever surface, this feature should not be
+ * too difficult to implement.
+ *
+ * Reduced Sample Rates
+ * No known samples exist. The spec also does not give clear information
+ * on how this is to be implemented.
+ *
+ * Dependent Streams
+ * Only the independent stream is currently decoded. Any dependent
+ * streams are skipped. We have only come across two examples of this, and
+ * they are both just test streams, one for HD-DVD and the other for
+ * Blu-ray.
+ *
+ * Transient Pre-noise Processing
+ * This is side information which a decoder should use to reduce artifacts
+ * caused by transients. There are samples which are known to have this
+ * information, but this decoder currently ignores it.
+ */
+
+
#include "avcodec.h"
+#include "internal.h"
+#include "aac_ac3_parser.h"
#include "ac3.h"
#include "ac3_parser.h"
#include "ac3dec.h"
#include "ac3dec_data.h"
+#include "eac3_data.h"
/** gain adaptive quantization mode */
typedef enum {
#define EAC3_SR_CODE_REDUCED 3
-
void ff_eac3_apply_spectral_extension(AC3DecodeContext *s)
{
int bin, bnd, ch, i;
- int wrapflag[SPX_MAX_BANDS]={0,}, num_copy_sections, copy_sizes[SPX_MAX_BANDS];
- int rms_energy[SPX_MAX_BANDS];
+ uint8_t wrapflag[SPX_MAX_BANDS]={1,0,}, num_copy_sections, copy_sizes[SPX_MAX_BANDS];
+ float rms_energy[SPX_MAX_BANDS];
/* Set copy index mapping table. Set wrap flags to apply a notch filter at
wrap points later on. */
- bin = s->spx_copy_start_freq;
+ bin = s->spx_dst_start_freq;
num_copy_sections = 0;
for (bnd = 0; bnd < s->num_spx_bands; bnd++) {
+ int copysize;
int bandsize = s->spx_band_sizes[bnd];
- if ((bin + bandsize) > s->spx_start_freq) {
- copy_sizes[num_copy_sections++] = bin - s->spx_copy_start_freq;
- bin = s->spx_copy_start_freq;
+ if (bin + bandsize > s->spx_src_start_freq) {
+ copy_sizes[num_copy_sections++] = bin - s->spx_dst_start_freq;
+ bin = s->spx_dst_start_freq;
wrapflag[bnd] = 1;
}
- for (i = 0; i < bandsize; i++) {
- if (bin == s->spx_start_freq) {
- copy_sizes[num_copy_sections++] = bin - s->spx_copy_start_freq;
- bin = s->spx_copy_start_freq;
+ for (i = 0; i < bandsize; i += copysize) {
+ if (bin == s->spx_src_start_freq) {
+ copy_sizes[num_copy_sections++] = bin - s->spx_dst_start_freq;
+ bin = s->spx_dst_start_freq;
}
- bin++;
+ copysize = FFMIN(bandsize - i, s->spx_src_start_freq - bin);
+ bin += copysize;
}
}
- copy_sizes[num_copy_sections++] = bin - s->spx_copy_start_freq;
+ copy_sizes[num_copy_sections++] = bin - s->spx_dst_start_freq;
for (ch = 1; ch <= s->fbw_channels; ch++) {
- if (!s->channel_in_spx[ch])
+ if (!s->channel_uses_spx[ch])
continue;
/* Copy coeffs from normal bands to extension bands */
- bin = s->spx_start_freq;
- for (bnd = 0; bnd < num_copy_sections; bnd++) {
- memcpy(&s->fixed_coeffs[ch][bin],
- &s->fixed_coeffs[ch][s->spx_copy_start_freq],
- copy_sizes[bnd]*sizeof(int));
- bin += copy_sizes[bnd];
+ bin = s->spx_src_start_freq;
+ for (i = 0; i < num_copy_sections; i++) {
+ memcpy(&s->transform_coeffs[ch][bin],
+ &s->transform_coeffs[ch][s->spx_dst_start_freq],
+ copy_sizes[i]*sizeof(float));
+ bin += copy_sizes[i];
}
/* Calculate RMS energy for each SPX band. */
- bin = s->spx_start_freq;
+ bin = s->spx_src_start_freq;
for (bnd = 0; bnd < s->num_spx_bands; bnd++) {
int bandsize = s->spx_band_sizes[bnd];
- int64_t accum = 0;
+ float accum = 0.0f;
for (i = 0; i < bandsize; i++) {
- int64_t coeff = s->fixed_coeffs[ch][bin++];
+ float coeff = s->transform_coeffs[ch][bin++];
accum += coeff * coeff;
}
- rms_energy[bnd] = ff_sqrt((accum >> 15) / bandsize) * M_SQRT_POW2_15;
+ rms_energy[bnd] = sqrtf(accum / bandsize);
}
/* Apply a notch filter at transitions between normal and extension
bands and at all wrap points. */
if (s->spx_atten_code[ch] >= 0) {
- const int32_t *atten_tab = ff_eac3_spx_atten_tab[s->spx_atten_code[ch]];
- /* apply notch filter at baseband / extension region border */
- bin = s->spx_start_freq - 2;
- for (i = 0; i < 5; i++) {
- s->fixed_coeffs[ch][bin] = ((int64_t)atten_tab[2-abs(i-2)] *
- (int64_t)s->fixed_coeffs[ch][bin]) >> 23;
- bin++;
- }
- /* apply notch at all other wrap points */
- bin += s->spx_band_sizes[0];
- for (bnd = 1; bnd < s->num_spx_bands; bnd++) {
+ const float *atten_tab = ff_eac3_spx_atten_tab[s->spx_atten_code[ch]];
+ bin = s->spx_src_start_freq - 2;
+ for (bnd = 0; bnd < s->num_spx_bands; bnd++) {
if (wrapflag[bnd]) {
- bin -= 5;
- for (i = 0; i < 5; i++) {
- s->fixed_coeffs[ch][bin] = (atten_tab[2-abs(i-2)] *
- (int64_t)s->fixed_coeffs[ch][bin]) >> 23;
- bin++;
- }
+ float *coeffs = &s->transform_coeffs[ch][bin];
+ coeffs[0] *= atten_tab[0];
+ coeffs[1] *= atten_tab[1];
+ coeffs[2] *= atten_tab[2];
+ coeffs[3] *= atten_tab[1];
+ coeffs[4] *= atten_tab[0];
}
bin += s->spx_band_sizes[bnd];
}
/* Apply noise-blended coefficient scaling based on previously
calculated RMS energy, blending factors, and SPX coordinates for
each band. */
- bin = s->spx_start_freq;
+ bin = s->spx_src_start_freq;
for (bnd = 0; bnd < s->num_spx_bands; bnd++) {
- int64_t nscale, sscale, spxco;
- nscale = (s->spx_noise_blend [ch][bnd] * rms_energy[bnd]) >> 23;
- nscale = (nscale * 14529495) >> 23;
- sscale = s->spx_signal_blend[ch][bnd];
- spxco = s->spx_coords[ch][bnd];
+ float nscale = s->spx_noise_blend[ch][bnd] * rms_energy[bnd] * (1.0f / INT32_MIN);
+ float sscale = s->spx_signal_blend[ch][bnd];
for (i = 0; i < s->spx_band_sizes[bnd]; i++) {
- int64_t noise = (nscale * (((int)av_lfg_get(&s->dith_state))>>8)) >> 23;
- int64_t signal = (sscale * s->fixed_coeffs[ch][bin]) >> 23;
- s->fixed_coeffs[ch][bin++] = ((noise + signal) * spxco) >> 23;
+ float noise = nscale * (int32_t)av_lfg_get(&s->dith_state);
+ s->transform_coeffs[ch][bin] *= sscale;
+ s->transform_coeffs[ch][bin++] += noise;
}
}
}
}
+
/** lrint(M_SQRT2*cos(2*M_PI/12)*(1<<23)) */
#define COEFF_0 10273905LL
for (blk = 0; blk < 6; blk++) {
int mant = get_sbits(gbc, gbits);
- if (mant == -(1 << (gbits-1))) {
+ if (log_gain && mant == -(1 << (gbits-1))) {
/* large mantissa */
int b;
- mant = get_sbits(gbc, bits-2+log_gain) << (26-log_gain-bits);
+ int mbits = bits - (2 - log_gain);
+ mant = get_sbits(gbc, mbits);
+ mant <<= (23 - (mbits - 1));
/* remap mantissa value to correct for asymmetric quantization */
if (mant >= 0)
- b = 32768 >> (log_gain+8);
+ b = 1 << (23 - log_gain);
else
- b = ff_eac3_gaq_remap_2_4_b[hebap-8][log_gain-1];
- mant += (ff_eac3_gaq_remap_2_4_a[hebap-8][log_gain-1] * (mant>>8) + b) >> 7;
+ b = ff_eac3_gaq_remap_2_4_b[hebap-8][log_gain-1] << 8;
+ mant += ((ff_eac3_gaq_remap_2_4_a[hebap-8][log_gain-1] * (int64_t)mant) >> 15) + b;
} else {
/* small mantissa, no GAQ, or Gk=1 */
mant <<= 24 - bits;
if (!log_gain) {
/* remap mantissa value for no GAQ or Gk=1 */
- mant += (ff_eac3_gaq_remap_1[hebap-8] * (mant>>8)) >> 7;
+ mant += (ff_eac3_gaq_remap_1[hebap-8] * (int64_t)mant) >> 15;
}
}
s->pre_mantissa[ch][bin][blk] = mant;
application can select from. each independent stream can also contain
dependent streams which are used to add or replace channels. */
if (s->frame_type == EAC3_FRAME_TYPE_DEPENDENT) {
- av_log_missing_feature(s->avctx, "Dependent substream decoding", 1);
- return AC3_PARSE_ERROR_FRAME_TYPE;
+ if (!s->eac3_frame_dependent_found) {
+ s->eac3_frame_dependent_found = 1;
+ avpriv_request_sample(s->avctx, "Dependent substream decoding");
+ }
+ return AAC_AC3_PARSE_ERROR_FRAME_TYPE;
} else if (s->frame_type == EAC3_FRAME_TYPE_RESERVED) {
av_log(s->avctx, AV_LOG_ERROR, "Reserved frame type\n");
- return AC3_PARSE_ERROR_FRAME_TYPE;
+ return AAC_AC3_PARSE_ERROR_FRAME_TYPE;
}
/* The substream id indicates which substream this frame belongs to. each
associated to an independent stream have matching substream id's. */
if (s->substreamid) {
/* only decode substream with id=0. skip any additional substreams. */
- av_log_missing_feature(s->avctx, "Additional substreams", 1);
- return AC3_PARSE_ERROR_FRAME_TYPE;
+ if (!s->eac3_subsbtreamid_found) {
+ s->eac3_subsbtreamid_found = 1;
+ avpriv_request_sample(s->avctx, "Additional substreams");
+ }
+ return AAC_AC3_PARSE_ERROR_FRAME_TYPE;
}
if (s->bit_alloc_params.sr_code == EAC3_SR_CODE_REDUCED) {
rates in bit allocation. The best assumption would be that it is
handled like AC-3 DolbyNet, but we cannot be sure until we have a
sample which utilizes this feature. */
- av_log_missing_feature(s->avctx, "Reduced sampling rates", 1);
- return -1;
+ avpriv_request_sample(s->avctx, "Reduced sampling rate");
+ return AVERROR_PATCHWELCOME;
}
skip_bits(gbc, 5); // skip bitstream id
if (get_bits1(gbc)) {
/* center and surround mix levels */
if (s->channel_mode > AC3_CHMODE_STEREO) {
- skip_bits(gbc, 2); // skip preferred stereo downmix mode
+ s->preferred_downmix = get_bits(gbc, 2);
if (s->channel_mode & 1) {
/* if three front channels exist */
- skip_bits(gbc, 3); //skip Lt/Rt center mix level
- s->center_mix_level = get_bits(gbc, 3);
+ s->center_mix_level_ltrt = get_bits(gbc, 3);
+ s->center_mix_level = get_bits(gbc, 3);
}
if (s->channel_mode & 4) {
/* if a surround channel exists */
- skip_bits(gbc, 3); //skip Lt/Rt surround mix level
- s->surround_mix_level = get_bits(gbc, 3);
+ s->surround_mix_level_ltrt = av_clip(get_bits(gbc, 3), 3, 7);
+ s->surround_mix_level = av_clip(get_bits(gbc, 3), 3, 7);
}
}
/* lfe mix level */
- if (s->lfe_on && get_bits1(gbc)) {
- // TODO: use LFE mix level
- skip_bits(gbc, 5); // skip LFE mix level code
+ if (s->lfe_on && (s->lfe_mix_level_exists = get_bits1(gbc))) {
+ s->lfe_mix_level = get_bits(gbc, 5);
}
/* info for mixing with other streams and substreams */
/* informational metadata */
if (get_bits1(gbc)) {
- skip_bits(gbc, 3); // skip bit stream mode
+ s->bitstream_mode = get_bits(gbc, 3);
skip_bits(gbc, 2); // skip copyright bit and original bitstream bit
if (s->channel_mode == AC3_CHMODE_STEREO) {
- skip_bits(gbc, 4); // skip Dolby surround and headphone mode
+ s->dolby_surround_mode = get_bits(gbc, 2);
+ s->dolby_headphone_mode = get_bits(gbc, 2);
}
if (s->channel_mode >= AC3_CHMODE_2F2R) {
- skip_bits(gbc, 2); // skip Dolby surround EX mode
+ s->dolby_surround_ex_mode = get_bits(gbc, 2);
}
for (i = 0; i < (s->channel_mode ? 1 : 2); i++) {
if (get_bits1(gbc)) {
s->skip_syntax = get_bits1(gbc);
parse_spx_atten_data = get_bits1(gbc);
- /* coupling strategy occurance and coupling use per block */
+ /* coupling strategy occurrence and coupling use per block */
num_cpl_blocks = 0;
if (s->channel_mode > 1) {
for (blk = 0; blk < s->num_blocks; blk++) {
/* spectral extension attenuation data */
for (ch = 1; ch <= s->fbw_channels; ch++) {
- if (parse_spx_atten_data && get_bits1(gbc))
+ if (parse_spx_atten_data && get_bits1(gbc)) {
s->spx_atten_code[ch] = get_bits(gbc, 5);
- else
+ } else {
s->spx_atten_code[ch] = -1;
- }
+ }
+ }
/* block start information */
if (s->num_blocks > 1 && get_bits1(gbc)) {
The spec does not say what this data is or what it's used for.
It is likely the offset of each block within the frame. */
int block_start_bits = (s->num_blocks-1) * (4 + av_log2(s->frame_size-2));
- skip_bits(gbc, block_start_bits);
+ skip_bits_long(gbc, block_start_bits);
+ avpriv_request_sample(s->avctx, "Block start info");
}
/* syntax state initialization */
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