/*
* 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) 2007 Justin Ruggles
+ * 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 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
*/
#include <math.h>
#include <string.h>
-#include "avcodec.h"
+#include "libavutil/crc.h"
+#include "libavutil/opt.h"
+#include "internal.h"
+#include "aac_ac3_parser.h"
#include "ac3_parser.h"
-#include "bitstream.h"
-#include "crc.h"
-#include "dsputil.h"
-#include "random.h"
+#include "ac3dec.h"
+#include "ac3dec_data.h"
+#include "kbdwin.h"
/**
- * Table of bin locations for rematrixing bands
- * reference: Section 7.5.2 Rematrixing : Frequency Band Definitions
+ * table for ungrouping 3 values in 7 bits.
+ * used for exponents and bap=2 mantissas
*/
-static const uint8_t rematrix_band_tab[5] = { 13, 25, 37, 61, 253 };
-
-/**
- * table for exponent to scale_factor mapping
- * scale_factors[i] = 2 ^ -i
- */
-static float scale_factors[25];
-
-/** table for grouping exponents */
-static uint8_t exp_ungroup_tab[128][3];
-
+static uint8_t ungroup_3_in_7_bits_tab[128][3];
/** tables for ungrouping mantissas */
-static float b1_mantissas[32][3];
-static float b2_mantissas[128][3];
-static float b3_mantissas[8];
-static float b4_mantissas[128][2];
-static float b5_mantissas[16];
+static int b1_mantissas[32][3];
+static int b2_mantissas[128][3];
+static int b3_mantissas[8];
+static int b4_mantissas[128][2];
+static int b5_mantissas[16];
/**
* Quantization table: levels for symmetric. bits for asymmetric.
static float dynamic_range_tab[256];
/** Adjustments in dB gain */
-#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[6] = {
- LEVEL_ZERO,
+static const float gain_levels[9] = {
+ LEVEL_PLUS_3DB,
+ LEVEL_PLUS_1POINT5DB,
LEVEL_ONE,
+ LEVEL_MINUS_1POINT5DB,
LEVEL_MINUS_3DB,
LEVEL_MINUS_4POINT5DB,
LEVEL_MINUS_6DB,
+ LEVEL_ZERO,
LEVEL_MINUS_9DB
};
-/**
- * Table for center mix levels
- * reference: Section 5.4.2.4 cmixlev
- */
-static const uint8_t center_levels[4] = { 2, 3, 4, 3 };
-
-/**
- * Table for surround mix levels
- * reference: Section 5.4.2.5 surmixlev
- */
-static const uint8_t surround_levels[4] = { 2, 4, 0, 4 };
-
/**
* Table for default stereo downmixing coefficients
* reference: Section 7.8.2 Downmixing Into Two Channels
*/
static const uint8_t ac3_default_coeffs[8][5][2] = {
- { { 1, 0 }, { 0, 1 }, },
- { { 2, 2 }, },
- { { 1, 0 }, { 0, 1 }, },
- { { 1, 0 }, { 3, 3 }, { 0, 1 }, },
- { { 1, 0 }, { 0, 1 }, { 4, 4 }, },
- { { 1, 0 }, { 3, 3 }, { 0, 1 }, { 5, 5 }, },
- { { 1, 0 }, { 0, 1 }, { 4, 0 }, { 0, 4 }, },
- { { 1, 0 }, { 3, 3 }, { 0, 1 }, { 4, 0 }, { 0, 4 }, },
+ { { 2, 7 }, { 7, 2 }, },
+ { { 4, 4 }, },
+ { { 2, 7 }, { 7, 2 }, },
+ { { 2, 7 }, { 5, 5 }, { 7, 2 }, },
+ { { 2, 7 }, { 7, 2 }, { 6, 6 }, },
+ { { 2, 7 }, { 5, 5 }, { 7, 2 }, { 8, 8 }, },
+ { { 2, 7 }, { 7, 2 }, { 6, 7 }, { 7, 6 }, },
+ { { 2, 7 }, { 5, 5 }, { 7, 2 }, { 6, 7 }, { 7, 6 }, },
};
-/* override ac3.h to include coupling channel */
-#undef AC3_MAX_CHANNELS
-#define AC3_MAX_CHANNELS 7
-#define CPL_CH 0
-
-#define AC3_OUTPUT_LFEON 8
-
-typedef struct {
- int channel_mode; ///< channel mode (acmod)
- int block_switch[AC3_MAX_CHANNELS]; ///< block switch flags
- int dither_flag[AC3_MAX_CHANNELS]; ///< dither flags
- int dither_all; ///< true if all channels are dithered
- int cpl_in_use; ///< coupling in use
- int channel_in_cpl[AC3_MAX_CHANNELS]; ///< channel in coupling
- int phase_flags_in_use; ///< phase flags in use
- int phase_flags[18]; ///< phase flags
- int cpl_band_struct[18]; ///< coupling band structure
- int num_rematrixing_bands; ///< number of rematrixing bands
- int rematrixing_flags[4]; ///< rematrixing flags
- int exp_strategy[AC3_MAX_CHANNELS]; ///< exponent strategies
- int snr_offset[AC3_MAX_CHANNELS]; ///< signal-to-noise ratio offsets
- int fast_gain[AC3_MAX_CHANNELS]; ///< fast gain values (signal-to-mask ratio)
- int dba_mode[AC3_MAX_CHANNELS]; ///< delta bit allocation mode
- int dba_nsegs[AC3_MAX_CHANNELS]; ///< number of delta segments
- uint8_t dba_offsets[AC3_MAX_CHANNELS][8]; ///< delta segment offsets
- uint8_t dba_lengths[AC3_MAX_CHANNELS][8]; ///< delta segment lengths
- uint8_t dba_values[AC3_MAX_CHANNELS][8]; ///< delta values for each segment
-
- int sample_rate; ///< sample frequency, in Hz
- int bit_rate; ///< stream bit rate, in bits-per-second
- int frame_size; ///< current frame size, in bytes
-
- int channels; ///< number of total channels
- int fbw_channels; ///< number of full-bandwidth channels
- int lfe_on; ///< lfe channel in use
- int lfe_ch; ///< index of LFE channel
- int output_mode; ///< output channel configuration
- int out_channels; ///< number of output channels
-
- int center_mix_level; ///< Center mix level index
- int surround_mix_level; ///< Surround mix level index
- float downmix_coeffs[AC3_MAX_CHANNELS][2]; ///< stereo downmix coefficients
- float dynamic_range[2]; ///< dynamic range
- float cpl_coords[AC3_MAX_CHANNELS][18]; ///< coupling coordinates
- int num_cpl_bands; ///< number of coupling bands
- int num_cpl_subbands; ///< number of coupling sub bands
- int start_freq[AC3_MAX_CHANNELS]; ///< start frequency bin
- int end_freq[AC3_MAX_CHANNELS]; ///< end frequency bin
- AC3BitAllocParameters bit_alloc_params; ///< bit allocation parameters
-
- int8_t dexps[AC3_MAX_CHANNELS][256]; ///< decoded exponents
- uint8_t bap[AC3_MAX_CHANNELS][256]; ///< bit allocation pointers
- int16_t psd[AC3_MAX_CHANNELS][256]; ///< scaled exponents
- int16_t band_psd[AC3_MAX_CHANNELS][50]; ///< interpolated exponents
- int16_t mask[AC3_MAX_CHANNELS][50]; ///< masking curve values
-
- DECLARE_ALIGNED_16(float, transform_coeffs[AC3_MAX_CHANNELS][256]); ///< transform coefficients
-
- /* For IMDCT. */
- MDCTContext imdct_512; ///< for 512 sample IMDCT
- MDCTContext imdct_256; ///< for 256 sample IMDCT
- DSPContext dsp; ///< for optimization
- float add_bias; ///< offset for float_to_int16 conversion
- float mul_bias; ///< scaling for float_to_int16 conversion
-
- DECLARE_ALIGNED_16(float, output[AC3_MAX_CHANNELS-1][256]); ///< output after imdct transform and windowing
- DECLARE_ALIGNED_16(short, int_output[AC3_MAX_CHANNELS-1][256]); ///< final 16-bit integer output
- DECLARE_ALIGNED_16(float, delay[AC3_MAX_CHANNELS-1][256]); ///< delay - added to the next block
- DECLARE_ALIGNED_16(float, tmp_imdct[256]); ///< temporary storage for imdct transform
- DECLARE_ALIGNED_16(float, tmp_output[512]); ///< temporary storage for output before windowing
- DECLARE_ALIGNED_16(float, window[256]); ///< window coefficients
-
- /* Miscellaneous. */
- GetBitContext gbc; ///< bitstream reader
- AVRandomState dith_state; ///< for dither generation
- AVCodecContext *avctx; ///< parent context
-} AC3DecodeContext;
-
-/**
- * Generate a Kaiser-Bessel Derived Window.
- */
-static void ac3_window_init(float *window)
-{
- int i, j;
- double sum = 0.0, bessel, tmp;
- double local_window[256];
- double alpha2 = (5.0 * M_PI / 256.0) * (5.0 * M_PI / 256.0);
-
- for (i = 0; i < 256; i++) {
- tmp = i * (256 - i) * alpha2;
- bessel = 1.0;
- for (j = 100; j > 0; j--) /* default to 100 iterations */
- bessel = bessel * tmp / (j * j) + 1;
- sum += bessel;
- local_window[i] = sum;
- }
-
- sum++;
- for (i = 0; i < 256; i++)
- window[i] = sqrt(local_window[i] / sum);
-}
-
/**
* Symmetrical Dequantization
* reference: Section 7.3.3 Expansion of Mantissas for Symmetrical Quantization
* Tables 7.19 to 7.23
*/
-static inline float
+static inline int
symmetric_dequant(int code, int levels)
{
- return (code - (levels >> 1)) * (2.0f / levels);
+ return ((code - (levels >> 1)) << 24) / levels;
}
/*
* Initialize tables at runtime.
*/
-static void ac3_tables_init(void)
+static av_cold void ac3_tables_init(void)
{
int i;
+ /* generate table for ungrouping 3 values in 7 bits
+ reference: Section 7.1.3 Exponent Decoding */
+ 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;
+ }
+
/* 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( i / 9 , 3);
- b1_mantissas[i][1] = symmetric_dequant((i % 9) / 3, 3);
- b1_mantissas[i][2] = symmetric_dequant((i % 9) % 3, 3);
+ 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( i / 25 , 5);
- b2_mantissas[i][1] = symmetric_dequant((i % 25) / 5, 5);
- b2_mantissas[i][2] = symmetric_dequant((i % 25) % 5, 5);
+ 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);
+ b2_mantissas[i][2] = symmetric_dequant(ungroup_3_in_7_bits_tab[i][2], 5);
/* bap=4 mantissas */
b4_mantissas[i][0] = symmetric_dequant(i / 11, 11);
}
/* 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);
}
-
- /* generate scale factors for exponents and asymmetrical dequantization
- reference: Section 7.3.2 Expansion of Mantissas for Asymmetric Quantization */
- for (i = 0; i < 25; i++)
- scale_factors[i] = pow(2.0, -i);
-
- /* generate exponent tables
- reference: Section 7.1.3 Exponent Decoding */
- for(i=0; i<128; i++) {
- exp_ungroup_tab[i][0] = i / 25;
- exp_ungroup_tab[i][1] = (i % 25) / 5;
- exp_ungroup_tab[i][2] = (i % 25) % 5;
- }
}
-
/**
* AVCodec initialization
*/
-static int ac3_decode_init(AVCodecContext *avctx)
+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);
- ac3_window_init(s->window);
- dsputil_init(&s->dsp, avctx);
- av_init_random(0, &s->dith_state);
-
- /* set bias values for float to int16 conversion */
- if(s->dsp.float_to_int16 == ff_float_to_int16_c) {
- s->add_bias = 385.0f;
+ 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);
+ 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 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 */
avctx->request_channels <= 2) {
avctx->channels = avctx->request_channels;
}
+ s->downmixed = 1;
+
+ avcodec_get_frame_defaults(&s->frame);
+ avctx->coded_frame = &s->frame;
return 0;
}
/**
* Parse the 'sync info' and 'bit stream info' from the AC-3 bitstream.
* GetBitContext within AC3DecodeContext must point to
- * start of the synchronized ac3 bitstream.
+ * the start of the synchronized AC-3 bitstream.
*/
static int ac3_parse_header(AC3DecodeContext *s)
{
- AC3HeaderInfo hdr;
GetBitContext *gbc = &s->gbc;
- int err, i;
-
- err = ff_ac3_parse_header(gbc->buffer, &hdr);
- if(err)
- return err;
-
- if(hdr.bitstream_id > 10)
- return AC3_PARSE_ERROR_BSID;
-
- /* get decoding parameters from header info */
- s->bit_alloc_params.sr_code = hdr.sr_code;
- s->channel_mode = hdr.channel_mode;
- s->lfe_on = hdr.lfe_on;
- s->bit_alloc_params.sr_shift = hdr.sr_shift;
- s->sample_rate = hdr.sample_rate;
- s->bit_rate = hdr.bit_rate;
- s->channels = hdr.channels;
- s->fbw_channels = s->channels - s->lfe_on;
- s->lfe_ch = s->fbw_channels + 1;
- s->frame_size = hdr.frame_size;
-
- /* set default output to all source channels */
- s->out_channels = s->channels;
- s->output_mode = s->channel_mode;
- if(s->lfe_on)
- s->output_mode |= AC3_OUTPUT_LFEON;
-
- /* set default mix levels */
- s->center_mix_level = 3; // -4.5dB
- s->surround_mix_level = 4; // -6.0dB
-
- /* skip over portion of header which has already been read */
- skip_bits(gbc, 16); // skip the sync_word
- skip_bits(gbc, 16); // skip crc1
- skip_bits(gbc, 8); // skip fscod and frmsizecod
- skip_bits(gbc, 11); // skip bsid, bsmod, and acmod
- if(s->channel_mode == AC3_CHMODE_STEREO) {
- skip_bits(gbc, 2); // skip dsurmod
- } else {
- if((s->channel_mode & 1) && s->channel_mode != AC3_CHMODE_MONO)
- s->center_mix_level = center_levels[get_bits(gbc, 2)];
- if(s->channel_mode & 4)
- s->surround_mix_level = surround_levels[get_bits(gbc, 2)];
- }
- skip_bits1(gbc); // skip lfeon
+ 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))
i = get_bits(gbc, 6);
do {
skip_bits(gbc, 8);
- } while(i--);
+ } while (i--);
}
return 0;
}
+/**
+ * Common function to parse AC-3 or E-AC-3 frame header
+ */
+static int parse_frame_header(AC3DecodeContext *s)
+{
+ AC3HeaderInfo hdr;
+ int 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;
+ s->bit_rate = hdr.bit_rate;
+ s->channels = hdr.channels;
+ s->fbw_channels = s->channels - s->lfe_on;
+ s->lfe_ch = s->fbw_channels + 1;
+ s->frame_size = hdr.frame_size;
+ s->center_mix_level = hdr.center_mix_level;
+ s->surround_mix_level = hdr.surround_mix_level;
+ s->num_blocks = hdr.num_blocks;
+ 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;
+ s->num_exp_groups[s->lfe_ch] = 2;
+ s->channel_in_cpl[s->lfe_ch] = 0;
+ }
+
+ 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;
+ }
+}
+
/**
* Set stereo downmixing coefficients based on frame header info.
* reference: Section 7.8.2 Downmixing Into Two Channels
static void set_downmix_coeffs(AC3DecodeContext *s)
{
int i;
- float cmix = gain_levels[s->center_mix_level];
+ float cmix = gain_levels[s-> center_mix_level];
float smix = gain_levels[s->surround_mix_level];
+ float norm0, norm1;
- for(i=0; i<s->fbw_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; 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; 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; i < s->fbw_channels; i++)
+ s->downmix_coeffs[i][0] = (s->downmix_coeffs[i][0] +
+ s->downmix_coeffs[i][1]) * LEVEL_MINUS_3DB;
+ }
}
/**
* 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];
/* unpack groups */
group_size = exp_strategy + (exp_strategy == EXP_D45);
- for(grp=0,i=0; grp<ngrps; grp++) {
+ for (grp = 0, i = 0; grp < ngrps; grp++) {
expacc = get_bits(gbc, 7);
- dexp[i++] = exp_ungroup_tab[expacc][0];
- dexp[i++] = exp_ungroup_tab[expacc][1];
- dexp[i++] = exp_ungroup_tab[expacc][2];
+ dexp[i++] = ungroup_3_in_7_bits_tab[expacc][0];
+ dexp[i++] = ungroup_3_in_7_bits_tab[expacc][1];
+ dexp[i++] = ungroup_3_in_7_bits_tab[expacc][2];
}
/* 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;
}
/**
* range using the coupling coefficients and coupling coordinates.
* reference: Section 7.4.3 Coupling Coordinate Format
*/
-static void uncouple_channels(AC3DecodeContext *s)
+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->transform_coeffs[ch][i] = s->transform_coeffs[CPL_CH][i] * s->cpl_coords[ch][bnd] * 8.0f;
- if (ch == 2 && s->phase_flags[bnd])
- s->transform_coeffs[ch][i] = -s->transform_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 {
- float b1_mant[3];
- float b2_mant[3];
- float 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 int 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;
- float *coeffs;
-
- exps = s->dexps[ch_index];
- bap = s->bap[ch_index];
- coeffs = s->transform_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) & 0xFFFF) / 65535.0f) - 0.5f;
- 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 */
- coeffs[i] = get_sbits(gbc, quantization_tab[tbap]) * scale_factors[quantization_tab[tbap]-1];
- 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] *= scale_factors[exps[i]];
+ coeffs[freq] = mantissa >> exps[freq];
}
-
- return 0;
}
/**
- * 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;
- float *coeffs;
- uint8_t *bap;
-
- for(ch=1; ch<=s->fbw_channels; ch++) {
- if(!s->dither_flag[ch]) {
- coeffs = s->transform_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] = 0.0f;
- }
- if(s->channel_in_cpl[ch]) {
- bap = s->bap[CPL_CH];
- for(; i<s->end_freq[CPL_CH]; i++) {
- if(!bap[i])
- coeffs[i] = 0.0f;
- }
+
+ 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 int 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 */
- if (get_transform_coeffs_ch(s, ch, &m))
- return -1;
+ 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) {
- if (get_transform_coeffs_ch(s, CPL_CH, &m)) {
- av_log(s->avctx, AV_LOG_ERROR, "error in decoupling channels\n");
- return -1;
- }
- uncouple_channels(s);
+ decode_transform_coeffs_ch(s, blk, CPL_CH, &m);
+ calc_transform_coeffs_cpl(s);
got_cplchan = 1;
}
end = s->end_freq[CPL_CH];
end = s->end_freq[ch];
}
do
- s->transform_coeffs[ch][end] = 0;
- while(++end < 256);
+ s->fixed_coeffs[ch][end] = 0;
+ while (++end < 256);
}
- /* if any channel doesn't use dithering, zero appropriate coefficients */
- if(!s->dither_all)
- remove_dithering(s);
-
- return 0;
+ /* zero the dithered coefficients for appropriate channels */
+ remove_dithering(s);
}
/**
{
int bnd, i;
int end, bndend;
- float tmp0, tmp1;
end = FFMIN(s->end_freq[1], s->end_freq[2]);
- for(bnd=0; bnd<s->num_rematrixing_bands; bnd++) {
- if(s->rematrixing_flags[bnd]) {
- bndend = FFMIN(end, rematrix_band_tab[bnd+1]);
- for(i=rematrix_band_tab[bnd]; i<bndend; i++) {
- tmp0 = s->transform_coeffs[1][i];
- tmp1 = s->transform_coeffs[2][i];
- s->transform_coeffs[1][i] = tmp0 + tmp1;
- s->transform_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];
}
}
}
}
-/**
- * Perform the 256-point IMDCT
- */
-static void do_imdct_256(AC3DecodeContext *s, int chindex)
-{
- int i, k;
- DECLARE_ALIGNED_16(float, x[128]);
- FFTComplex z[2][64];
- float *o_ptr = s->tmp_output;
-
- for(i=0; i<2; i++) {
- /* de-interleave coefficients */
- for(k=0; k<128; k++) {
- x[k] = s->transform_coeffs[chindex][2*k+i];
- }
-
- /* run standard IMDCT */
- s->imdct_256.fft.imdct_calc(&s->imdct_256, o_ptr, x, s->tmp_imdct);
-
- /* reverse the post-rotation & reordering from standard IMDCT */
- for(k=0; k<32; k++) {
- z[i][32+k].re = -o_ptr[128+2*k];
- z[i][32+k].im = -o_ptr[2*k];
- z[i][31-k].re = o_ptr[2*k+1];
- z[i][31-k].im = o_ptr[128+2*k+1];
- }
- }
-
- /* apply AC-3 post-rotation & reordering */
- for(k=0; k<64; k++) {
- o_ptr[ 2*k ] = -z[0][ k].im;
- o_ptr[ 2*k+1] = z[0][63-k].re;
- o_ptr[128+2*k ] = -z[0][ k].re;
- o_ptr[128+2*k+1] = z[0][63-k].im;
- o_ptr[256+2*k ] = -z[1][ k].re;
- o_ptr[256+2*k+1] = z[1][63-k].im;
- o_ptr[384+2*k ] = z[1][ k].im;
- o_ptr[384+2*k+1] = -z[1][63-k].re;
- }
-}
-
/**
* Inverse MDCT Transform.
* Convert frequency domain coefficients to time-domain audio samples.
* reference: Section 7.9.4 Transformation Equations
*/
-static inline void do_imdct(AC3DecodeContext *s)
+static inline void do_imdct(AC3DecodeContext *s, int channels)
{
int ch;
- int channels;
- /* Don't perform the IMDCT on the LFE channel unless it's used in the output */
- channels = s->fbw_channels;
- if(s->output_mode & AC3_OUTPUT_LFEON)
- channels++;
-
- for (ch=1; ch<=channels; ch++) {
+ for (ch = 1; ch <= channels; ch++) {
if (s->block_switch[ch]) {
- do_imdct_256(s, ch);
+ int i;
+ 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 {
- s->imdct_512.fft.imdct_calc(&s->imdct_512, s->tmp_output,
- s->transform_coeffs[ch], s->tmp_imdct);
+ 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));
}
- /* For the first half of the block, apply the window, add the delay
- from the previous block, and send to output */
- s->dsp.vector_fmul_add_add(s->output[ch-1], s->tmp_output,
- s->window, s->delay[ch-1], 0, 256, 1);
- /* For the second half of the block, apply the window and store the
- samples to delay, to be combined with the next block */
- s->dsp.vector_fmul_reverse(s->delay[ch-1], s->tmp_output+256,
- s->window, 256);
}
}
/**
* Downmix the output to mono or stereo.
*/
-static void ac3_downmix(AC3DecodeContext *s)
+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, s0, s1;
-
- for(i=0; i<256; i++) {
- v0 = v1 = s0 = s1 = 0.0f;
- for(j=0; j<s->fbw_channels; j++) {
- v0 += s->output[j][i] * s->downmix_coeffs[j][0];
- v1 += s->output[j][i] * s->downmix_coeffs[j][1];
- s0 += s->downmix_coeffs[j][0];
- s1 += s->downmix_coeffs[j][1];
+ float v0, v1;
+ if (out_ch == 2) {
+ for (i = 0; i < len; i++) {
+ v0 = v1 = 0.0f;
+ for (j = 0; j < in_ch; j++) {
+ v0 += samples[j][i] * matrix[j][0];
+ v1 += samples[j][i] * matrix[j][1];
+ }
+ samples[0][i] = v0;
+ samples[1][i] = v1;
+ }
+ } else if (out_ch == 1) {
+ for (i = 0; i < len; i++) {
+ v0 = 0.0f;
+ for (j = 0; j < in_ch; j++)
+ v0 += samples[j][i] * matrix[j][0];
+ samples[0][i] = v0;
+ }
+ }
+}
+
+/**
+ * Upmix delay samples from stereo to original channel layout.
+ */
+static void ac3_upmix_delay(AC3DecodeContext *s)
+{
+ 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);
}
- v0 /= s0;
- v1 /= s1;
- if(s->output_mode == AC3_CHMODE_MONO) {
- s->output[0][i] = (v0 + v1) * LEVEL_MINUS_3DB;
- } else if(s->output_mode == AC3_CHMODE_STEREO) {
- s->output[0][i] = v0;
- s->output[1][i] = v1;
+ 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);
}
/**
- * Parse an audio block from AC-3 bitstream.
+ * Decode a single audio block from the AC-3 bitstream.
*/
-static int ac3_parse_audio_block(AC3DecodeContext *s, int blk)
+static int decode_audio_block(AC3DecodeContext *s, int blk)
{
int fbw_channels = s->fbw_channels;
int channel_mode = s->channel_mode;
int i, bnd, seg, ch;
+ int different_transforms;
+ 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 */
- for (ch = 1; ch <= fbw_channels; ch++)
- s->block_switch[ch] = get_bits1(gbc);
+ different_transforms = 0;
+ 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 = get_bits1(gbc);
- if (s->cpl_in_use) {
+ 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];
}
}
+ cpl_in_use = s->cpl_in_use[blk];
/* coupling coordinates */
- if (s->cpl_in_use) {
+ if (cpl_in_use) {
int cpl_coords_exist = 0;
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++) {
cpl_coord_exp = get_bits(gbc, 4);
cpl_coord_mant = get_bits(gbc, 4);
if (cpl_coord_exp == 15)
- s->cpl_coords[ch][bnd] = cpl_coord_mant / 16.0f;
+ s->cpl_coords[ch][bnd] = cpl_coord_mant << 22;
else
- s->cpl_coords[ch][bnd] = (cpl_coord_mant + 16.0f) / 32.0f;
- s->cpl_coords[ch][bnd] *= scale_factors[cpl_coord_exp + master_cpl_coord];
+ s->cpl_coords[ch][bnd] = (cpl_coord_mant + 16) << 21;
+ 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");
+ return -1;
}
+ } else {
+ /* channel not in coupling */
+ s->first_cpl_coords[ch] = 1;
}
}
/* phase flags */
/* 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(s->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; bnd<s->num_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_WARNING, "Warning: "
+ "new rematrixing strategy not present in block 0\n");
+ s->num_rematrixing_bands = 0;
}
}
/* exponent strategies for each channel */
- s->exp_strategy[CPL_CH] = EXP_REUSE;
- s->exp_strategy[s->lfe_ch] = EXP_REUSE;
- for (ch = !s->cpl_in_use; ch <= s->channels; ch++) {
- if(ch == s->lfe_ch)
- s->exp_strategy[ch] = get_bits(gbc, 1);
- else
- s->exp_strategy[ch] = get_bits(gbc, 2);
- if(s->exp_strategy[ch] != EXP_REUSE)
+ for (ch = !cpl_in_use; ch <= s->channels; 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;
}
/* channel bandwidth */
for (ch = 1; ch <= fbw_channels; ch++) {
s->start_freq[ch] = 0;
- if (s->exp_strategy[ch] != EXP_REUSE) {
+ if (s->exp_strategy[blk][ch] != EXP_REUSE) {
+ int group_size;
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;
}
- if(blk > 0 && s->end_freq[ch] != prev)
+ 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)
memset(bit_alloc_stages, 3, AC3_MAX_CHANNELS);
}
}
- s->start_freq[s->lfe_ch] = 0;
- s->end_freq[s->lfe_ch] = 7;
+ if (cpl_in_use && s->exp_strategy[blk][CPL_CH] != EXP_REUSE) {
+ s->num_exp_groups[CPL_CH] = (s->end_freq[CPL_CH] - s->start_freq[CPL_CH]) /
+ (3 << (s->exp_strategy[blk][CPL_CH] - 1));
+ }
/* decode exponents for each channel */
- for (ch = !s->cpl_in_use; ch <= s->channels; ch++) {
- if (s->exp_strategy[ch] != EXP_REUSE) {
- int group_size, num_groups;
- group_size = 3 << (s->exp_strategy[ch] - 1);
- if(ch == CPL_CH)
- num_groups = (s->end_freq[ch] - s->start_freq[ch]) / group_size;
- else if(ch == s->lfe_ch)
- num_groups = 2;
- else
- num_groups = (s->end_freq[ch] + group_size - 4) / group_size;
+ 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[ch], num_groups, 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=!s->cpl_in_use; ch<=s->channels; ch++) {
- bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2);
+ 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 = !s->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 (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 (s->cpl_in_use && 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);
+ if (cpl_in_use) {
+ 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 = !s->cpl_in_use; ch <= fbw_channels; ch++) {
+ for (ch = !cpl_in_use; ch <= fbw_channels; ch++) {
s->dba_mode[ch] = get_bits(gbc, 2);
if (s->dba_mode[ch] == DBA_RESERVED) {
av_log(s->avctx, AV_LOG_ERROR, "delta bit allocation strategy reserved\n");
bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2);
}
/* channel delta offset, len and bit allocation */
- for (ch = !s->cpl_in_use; ch <= fbw_channels; ch++) {
+ 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=!s->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,
- 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. */
- if (get_transform_coeffs(s)) {
- av_log(s->avctx, AV_LOG_ERROR, "Error in routine get_transform_coeffs\n");
- return -1;
- }
+ 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++) {
- float gain = 2.0f * s->mul_bias;
- if(s->channel_mode == AC3_CHMODE_DUALMONO) {
- gain *= s->dynamic_range[ch-1];
+ 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[2 - ch];
} else {
gain *= s->dynamic_range[0];
}
- for(i=0; i<s->end_freq[ch]; i++) {
- s->transform_coeffs[ch][i] *= gain;
- }
+ s->fmt_conv.int32_to_float_fmul_scalar(s->transform_coeffs[ch],
+ s->fixed_coeffs[ch], gain, 256);
}
- do_imdct(s);
-
- /* downmix output if needed */
- if(s->channels != s->out_channels && !((s->output_mode & AC3_OUTPUT_LFEON) &&
- s->fbw_channels == s->out_channels)) {
- ac3_downmix(s);
+ /* apply spectral extension to high frequency bins */
+ if (s->spx_in_use && CONFIG_EAC3_DECODER) {
+ ff_eac3_apply_spectral_extension(s);
}
- /* convert float to 16-bit integer */
- for(ch=0; ch<s->out_channels; ch++) {
- for(i=0; i<256; i++) {
- s->output[ch][i] += s->add_bias;
+ /* downmix and MDCT. order depends on whether block switching is used for
+ any channel in this block. this is because coefficients for the long
+ and short transforms cannot be mixed. */
+ downmix_output = s->channels != s->out_channels &&
+ !((s->output_mode & AC3_OUTPUT_LFEON) &&
+ s->fbw_channels == s->out_channels);
+ 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) {
+ 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);
}
- s->dsp.float_to_int16(s->int_output[ch], s->output[ch], 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->downmixed) {
+ s->downmixed = 1;
+ s->dsp.ac3_downmix(s->delay, s->downmix_coeffs, s->out_channels,
+ s->fbw_channels, 128);
+ }
+
+ do_imdct(s, s->out_channels);
}
return 0;
/**
* Decode a single AC-3 frame.
*/
-static int ac3_decode_frame(AVCodecContext * avctx, void *data, int *data_size, 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 i, 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 */
init_get_bits(&s->gbc, buf, buf_size * 8);
/* parse the syncinfo */
- err = ac3_parse_header(s);
- if(err) {
- switch(err) {
- case AC3_PARSE_ERROR_SYNC:
- av_log(avctx, AV_LOG_ERROR, "frame sync error\n");
- break;
- 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;
- default:
- av_log(avctx, AV_LOG_ERROR, "invalid header\n");
- break;
- }
- return -1;
- }
+ 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");
- return -1;
- }
-
- /* check for crc mismatch */
- if(avctx->error_resilience > 0) {
- 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");
+ 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;
+ }
+ } 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;
+ }
}
- /* TODO: error concealment */
}
- avctx->sample_rate = s->sample_rate;
- avctx->bit_rate = s->bit_rate;
+ /* if frame is ok, set audio parameters */
+ if (!err) {
+ avctx->sample_rate = s->sample_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 |= 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->channel_layout = s->channel_layout;
- /* channel config */
- s->out_channels = s->channels;
- 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;
+ /* set downmixing coefficients if needed */
+ 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)
+ s->output_mode = s->out_channels == 1 ? AC3_CHMODE_MONO : AC3_CHMODE_STEREO;
}
- avctx->channels = s->out_channels;
-
- /* set downmixing coefficients if needed */
- if(s->channels != s->out_channels && !((s->output_mode & AC3_OUTPUT_LFEON) &&
- s->fbw_channels == s->out_channels)) {
- set_downmix_coeffs(s);
+ /* 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;
}
-
- /* parse the audio blocks */
- for (blk = 0; blk < NB_BLOCKS; blk++) {
- if (ac3_parse_audio_block(s, blk)) {
- av_log(avctx, AV_LOG_ERROR, "error parsing the audio block\n");
- *data_size = 0;
- return s->frame_size;
+ 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++) {
+ 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 (i = 0; i < 256; i++)
- for (ch = 0; ch < s->out_channels; ch++)
- *(out_samples++) = s->int_output[ch][i];
}
- *data_size = NB_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);
}
/**
* Uninitialize the AC-3 decoder.
*/
-static int ac3_decode_end(AVCodecContext *avctx)
+static av_cold int ac3_decode_end(AVCodecContext *avctx)
{
AC3DecodeContext *s = avctx->priv_data;
ff_mdct_end(&s->imdct_512);
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,
+ .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
projects / ffmpeg / blobdiff