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Move E-AC-3 encoder functions to a separate eac3enc.c file.

tags/n0.8
Justin Ruggles 14 years ago
parent
787a13535a
commit
c8e9ea43d0
5 changed files with 396 additions and 280 deletions
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  1. +2
    -1
      libavcodec/Makefile
  2. +5
    -279
      libavcodec/ac3enc.c
  3. +214
    -0
      libavcodec/ac3enc.h
  4. +131
    -0
      libavcodec/eac3enc.c
  5. +44
    -0
      libavcodec/eac3enc.h

+ 2
- 1
libavcodec/Makefile View File

@@ -124,7 +124,8 @@ OBJS-$(CONFIG_DVVIDEO_DECODER) += dv.o dvdata.o
OBJS-$(CONFIG_DVVIDEO_ENCODER) += dv.o dvdata.o
OBJS-$(CONFIG_DXA_DECODER) += dxa.o
OBJS-$(CONFIG_EAC3_DECODER) += eac3dec.o eac3dec_data.o
OBJS-$(CONFIG_EAC3_ENCODER) += ac3enc_float.o ac3tab.o ac3.o kbdwin.o
OBJS-$(CONFIG_EAC3_ENCODER) += eac3enc.o ac3enc_float.o ac3tab.o \
ac3.o kbdwin.o
OBJS-$(CONFIG_EACMV_DECODER) += eacmv.o
OBJS-$(CONFIG_EAMAD_DECODER) += eamad.o eaidct.o mpeg12.o \
mpeg12data.o mpegvideo.o \


+ 5
- 279
libavcodec/ac3enc.c View File

@@ -42,183 +42,8 @@
#include "ac3.h"
#include "audioconvert.h"
#include "fft.h"


#ifndef CONFIG_AC3ENC_FLOAT
#define CONFIG_AC3ENC_FLOAT 0
#endif


#if CONFIG_AC3ENC_FLOAT
#define MAC_COEF(d,a,b) ((d)+=(a)*(b))
typedef float SampleType;
typedef float CoefType;
typedef float CoefSumType;
#else
#define MAC_COEF(d,a,b) MAC64(d,a,b)
typedef int16_t SampleType;
typedef int32_t CoefType;
typedef int64_t CoefSumType;
#endif

typedef struct AC3MDCTContext {
const SampleType *window; ///< MDCT window function
FFTContext fft; ///< FFT context for MDCT calculation
} AC3MDCTContext;

/**
* Encoding Options used by AVOption.
*/
typedef struct AC3EncOptions {
/* AC-3 metadata options*/
int dialogue_level;
int bitstream_mode;
float center_mix_level;
float surround_mix_level;
int dolby_surround_mode;
int audio_production_info;
int mixing_level;
int room_type;
int copyright;
int original;
int extended_bsi_1;
int preferred_stereo_downmix;
float ltrt_center_mix_level;
float ltrt_surround_mix_level;
float loro_center_mix_level;
float loro_surround_mix_level;
int extended_bsi_2;
int dolby_surround_ex_mode;
int dolby_headphone_mode;
int ad_converter_type;

/* other encoding options */
int allow_per_frame_metadata;
int stereo_rematrixing;
int channel_coupling;
int cpl_start;
} AC3EncOptions;

/**
* Data for a single audio block.
*/
typedef struct AC3Block {
CoefType **mdct_coef; ///< MDCT coefficients
int32_t **fixed_coef; ///< fixed-point MDCT coefficients
uint8_t **exp; ///< original exponents
uint8_t **grouped_exp; ///< grouped exponents
int16_t **psd; ///< psd per frequency bin
int16_t **band_psd; ///< psd per critical band
int16_t **mask; ///< masking curve
uint16_t **qmant; ///< quantized mantissas
uint8_t **cpl_coord_exp; ///< coupling coord exponents (cplcoexp)
uint8_t **cpl_coord_mant; ///< coupling coord mantissas (cplcomant)
uint8_t coeff_shift[AC3_MAX_CHANNELS]; ///< fixed-point coefficient shift values
uint8_t new_rematrixing_strategy; ///< send new rematrixing flags in this block
int num_rematrixing_bands; ///< number of rematrixing bands
uint8_t rematrixing_flags[4]; ///< rematrixing flags
int new_cpl_strategy; ///< send new coupling strategy
int cpl_in_use; ///< coupling in use for this block (cplinu)
uint8_t channel_in_cpl[AC3_MAX_CHANNELS]; ///< channel in coupling (chincpl)
int num_cpl_channels; ///< number of channels in coupling
uint8_t new_cpl_coords; ///< send new coupling coordinates (cplcoe)
uint8_t cpl_master_exp[AC3_MAX_CHANNELS]; ///< coupling coord master exponents (mstrcplco)
int new_snr_offsets; ///< send new SNR offsets
int new_cpl_leak; ///< send new coupling leak info
int end_freq[AC3_MAX_CHANNELS]; ///< end frequency bin (endmant)
} AC3Block;

/**
* AC-3 encoder private context.
*/
typedef struct AC3EncodeContext {
AVClass *av_class; ///< AVClass used for AVOption
AC3EncOptions options; ///< encoding options
PutBitContext pb; ///< bitstream writer context
DSPContext dsp;
AC3DSPContext ac3dsp; ///< AC-3 optimized functions
AC3MDCTContext mdct; ///< MDCT context

AC3Block blocks[AC3_MAX_BLOCKS]; ///< per-block info

int eac3; ///< indicates if this is E-AC-3 vs. AC-3
int bitstream_id; ///< bitstream id (bsid)
int bitstream_mode; ///< bitstream mode (bsmod)

int bit_rate; ///< target bit rate, in bits-per-second
int sample_rate; ///< sampling frequency, in Hz

int frame_size_min; ///< minimum frame size in case rounding is necessary
int frame_size; ///< current frame size in bytes
int frame_size_code; ///< frame size code (frmsizecod)
uint16_t crc_inv[2];
int64_t bits_written; ///< bit count (used to avg. bitrate)
int64_t samples_written; ///< sample count (used to avg. bitrate)

int fbw_channels; ///< number of full-bandwidth channels (nfchans)
int channels; ///< total number of channels (nchans)
int lfe_on; ///< indicates if there is an LFE channel (lfeon)
int lfe_channel; ///< channel index of the LFE channel
int has_center; ///< indicates if there is a center channel
int has_surround; ///< indicates if there are one or more surround channels
int channel_mode; ///< channel mode (acmod)
const uint8_t *channel_map; ///< channel map used to reorder channels

int center_mix_level; ///< center mix level code
int surround_mix_level; ///< surround mix level code
int ltrt_center_mix_level; ///< Lt/Rt center mix level code
int ltrt_surround_mix_level; ///< Lt/Rt surround mix level code
int loro_center_mix_level; ///< Lo/Ro center mix level code
int loro_surround_mix_level; ///< Lo/Ro surround mix level code

int cutoff; ///< user-specified cutoff frequency, in Hz
int bandwidth_code; ///< bandwidth code (0 to 60) (chbwcod)
int start_freq[AC3_MAX_CHANNELS]; ///< start frequency bin (strtmant)
int cpl_end_freq; ///< coupling channel end frequency bin

int cpl_on; ///< coupling turned on for this frame
int cpl_enabled; ///< coupling enabled for all frames
int num_cpl_subbands; ///< number of coupling subbands (ncplsubnd)
int num_cpl_bands; ///< number of coupling bands (ncplbnd)
uint8_t cpl_band_sizes[AC3_MAX_CPL_BANDS]; ///< number of coeffs in each coupling band

int rematrixing_enabled; ///< stereo rematrixing enabled

/* bitrate allocation control */
int slow_gain_code; ///< slow gain code (sgaincod)
int slow_decay_code; ///< slow decay code (sdcycod)
int fast_decay_code; ///< fast decay code (fdcycod)
int db_per_bit_code; ///< dB/bit code (dbpbcod)
int floor_code; ///< floor code (floorcod)
AC3BitAllocParameters bit_alloc; ///< bit allocation parameters
int coarse_snr_offset; ///< coarse SNR offsets (csnroffst)
int fast_gain_code[AC3_MAX_CHANNELS]; ///< fast gain codes (signal-to-mask ratio) (fgaincod)
int fine_snr_offset[AC3_MAX_CHANNELS]; ///< fine SNR offsets (fsnroffst)
int frame_bits_fixed; ///< number of non-coefficient bits for fixed parameters
int frame_bits; ///< all frame bits except exponents and mantissas
int exponent_bits; ///< number of bits used for exponents

SampleType **planar_samples;
uint8_t *bap_buffer;
uint8_t *bap1_buffer;
CoefType *mdct_coef_buffer;
int32_t *fixed_coef_buffer;
uint8_t *exp_buffer;
uint8_t *grouped_exp_buffer;
int16_t *psd_buffer;
int16_t *band_psd_buffer;
int16_t *mask_buffer;
uint16_t *qmant_buffer;
uint8_t *cpl_coord_exp_buffer;
uint8_t *cpl_coord_mant_buffer;

uint8_t exp_strategy[AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]; ///< exponent strategies
uint8_t exp_ref_block[AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]; ///< reference blocks for EXP_REUSE
uint8_t *ref_bap [AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]; ///< bit allocation pointers (bap)
int ref_bap_set; ///< indicates if ref_bap pointers have been set

DECLARE_ALIGNED(32, SampleType, windowed_samples)[AC3_WINDOW_SIZE];
} AC3EncodeContext;
#include "ac3enc.h"
#include "eac3enc.h"

typedef struct AC3Mant {
uint16_t *qmant1_ptr, *qmant2_ptr, *qmant4_ptr; ///< mantissa pointers for bap=1,2,4
@@ -741,34 +566,8 @@ static void apply_channel_coupling(AC3EncodeContext *s)
}
}

if (s->eac3) {
/* set first cpl coords */
int first_cpl_coords[AC3_MAX_CHANNELS];
for (ch = 1; ch <= s->fbw_channels; ch++)
first_cpl_coords[ch] = 1;
for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
AC3Block *block = &s->blocks[blk];
for (ch = 1; ch <= s->fbw_channels; ch++) {
if (block->channel_in_cpl[ch]) {
if (first_cpl_coords[ch]) {
block->new_cpl_coords = 2;
first_cpl_coords[ch] = 0;
}
} else {
first_cpl_coords[ch] = 1;
}
}
}

/* set first cpl leak */
for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
AC3Block *block = &s->blocks[blk];
if (block->cpl_in_use) {
block->new_cpl_leak = 2;
break;
}
}
}
if (s->eac3)
ff_eac3_set_cpl_states(s);
#endif /* CONFIG_AC3ENC_FLOAT */
}

@@ -1905,79 +1704,6 @@ static void ac3_output_frame_header(AC3EncodeContext *s)
}


/**
* Write the E-AC-3 frame header to the output bitstream.
*/
static void eac3_output_frame_header(AC3EncodeContext *s)
{
int blk, ch;
AC3EncOptions *opt = &s->options;

put_bits(&s->pb, 16, 0x0b77); /* sync word */

/* BSI header */
put_bits(&s->pb, 2, 0); /* stream type = independent */
put_bits(&s->pb, 3, 0); /* substream id = 0 */
put_bits(&s->pb, 11, (s->frame_size / 2) - 1); /* frame size */
if (s->bit_alloc.sr_shift) {
put_bits(&s->pb, 2, 0x3); /* fscod2 */
put_bits(&s->pb, 2, s->bit_alloc.sr_code); /* sample rate code */
} else {
put_bits(&s->pb, 2, s->bit_alloc.sr_code); /* sample rate code */
put_bits(&s->pb, 2, 0x3); /* number of blocks = 6 */
}
put_bits(&s->pb, 3, s->channel_mode); /* audio coding mode */
put_bits(&s->pb, 1, s->lfe_on); /* LFE channel indicator */
put_bits(&s->pb, 5, s->bitstream_id); /* bitstream id (EAC3=16) */
put_bits(&s->pb, 5, -opt->dialogue_level); /* dialogue normalization level */
put_bits(&s->pb, 1, 0); /* no compression gain */
put_bits(&s->pb, 1, 0); /* no mixing metadata */
/* TODO: mixing metadata */
put_bits(&s->pb, 1, 0); /* no info metadata */
/* TODO: info metadata */
put_bits(&s->pb, 1, 0); /* no additional bit stream info */

/* frame header */
put_bits(&s->pb, 1, 1); /* exponent strategy syntax = each block */
put_bits(&s->pb, 1, 0); /* aht enabled = no */
put_bits(&s->pb, 2, 0); /* snr offset strategy = 1 */
put_bits(&s->pb, 1, 0); /* transient pre-noise processing enabled = no */
put_bits(&s->pb, 1, 0); /* block switch syntax enabled = no */
put_bits(&s->pb, 1, 0); /* dither flag syntax enabled = no */
put_bits(&s->pb, 1, 0); /* bit allocation model syntax enabled = no */
put_bits(&s->pb, 1, 0); /* fast gain codes enabled = no */
put_bits(&s->pb, 1, 0); /* dba syntax enabled = no */
put_bits(&s->pb, 1, 0); /* skip field syntax enabled = no */
put_bits(&s->pb, 1, 0); /* spx enabled = no */
/* coupling strategy use flags */
if (s->channel_mode > AC3_CHMODE_MONO) {
put_bits(&s->pb, 1, s->blocks[0].cpl_in_use);
for (blk = 1; blk < AC3_MAX_BLOCKS; blk++) {
AC3Block *block = &s->blocks[blk];
put_bits(&s->pb, 1, block->new_cpl_strategy);
if (block->new_cpl_strategy)
put_bits(&s->pb, 1, block->cpl_in_use);
}
}
/* exponent strategy */
for (blk = 0; blk < AC3_MAX_BLOCKS; blk++)
for (ch = !s->blocks[blk].cpl_in_use; ch <= s->fbw_channels; ch++)
put_bits(&s->pb, 2, s->exp_strategy[ch][blk]);
if (s->lfe_on) {
for (blk = 0; blk < AC3_MAX_BLOCKS; blk++)
put_bits(&s->pb, 1, s->exp_strategy[s->lfe_channel][blk]);
}
/* E-AC-3 to AC-3 converter exponent strategy (unfortunately not optional...) */
for (ch = 1; ch <= s->fbw_channels; ch++)
put_bits(&s->pb, 5, 0);
/* snr offsets */
put_bits(&s->pb, 6, s->coarse_snr_offset);
put_bits(&s->pb, 4, s->fine_snr_offset[1]);
/* block start info */
put_bits(&s->pb, 1, 0);
}


/**
* Write one audio block to the output bitstream.
*/
@@ -2262,7 +1988,7 @@ static void output_frame(AC3EncodeContext *s, unsigned char *frame)
init_put_bits(&s->pb, frame, AC3_MAX_CODED_FRAME_SIZE);

if (s->eac3)
eac3_output_frame_header(s);
ff_eac3_output_frame_header(s);
else
ac3_output_frame_header(s);



+ 214
- 0
libavcodec/ac3enc.h View File

@@ -0,0 +1,214 @@
/*
* AC-3 encoder & E-AC-3 encoder common header
* Copyright (c) 2000 Fabrice Bellard
* Copyright (c) 2006-2010 Justin Ruggles <justin.ruggles@gmail.com>
*
* This file is part of Libav.
*
* 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.
*
* 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/

/**
* @file
* AC-3 encoder & E-AC-3 encoder common header
*/

#ifndef AVCODEC_AC3ENC_H
#define AVCODEC_AC3ENC_H

#include <stdint.h>
#include "ac3.h"
#include "ac3dsp.h"
#include "avcodec.h"
#include "dsputil.h"
#include "put_bits.h"
#include "fft.h"

#ifndef CONFIG_AC3ENC_FLOAT
#define CONFIG_AC3ENC_FLOAT 0
#endif

#if CONFIG_AC3ENC_FLOAT
#define MAC_COEF(d,a,b) ((d)+=(a)*(b))
typedef float SampleType;
typedef float CoefType;
typedef float CoefSumType;
#else
#define MAC_COEF(d,a,b) MAC64(d,a,b)
typedef int16_t SampleType;
typedef int32_t CoefType;
typedef int64_t CoefSumType;
#endif

typedef struct AC3MDCTContext {
const SampleType *window; ///< MDCT window function
FFTContext fft; ///< FFT context for MDCT calculation
} AC3MDCTContext;

/**
* Encoding Options used by AVOption.
*/
typedef struct AC3EncOptions {
/* AC-3 metadata options*/
int dialogue_level;
int bitstream_mode;
float center_mix_level;
float surround_mix_level;
int dolby_surround_mode;
int audio_production_info;
int mixing_level;
int room_type;
int copyright;
int original;
int extended_bsi_1;
int preferred_stereo_downmix;
float ltrt_center_mix_level;
float ltrt_surround_mix_level;
float loro_center_mix_level;
float loro_surround_mix_level;
int extended_bsi_2;
int dolby_surround_ex_mode;
int dolby_headphone_mode;
int ad_converter_type;

/* other encoding options */
int allow_per_frame_metadata;
int stereo_rematrixing;
int channel_coupling;
int cpl_start;
} AC3EncOptions;

/**
* Data for a single audio block.
*/
typedef struct AC3Block {
CoefType **mdct_coef; ///< MDCT coefficients
int32_t **fixed_coef; ///< fixed-point MDCT coefficients
uint8_t **exp; ///< original exponents
uint8_t **grouped_exp; ///< grouped exponents
int16_t **psd; ///< psd per frequency bin
int16_t **band_psd; ///< psd per critical band
int16_t **mask; ///< masking curve
uint16_t **qmant; ///< quantized mantissas
uint8_t **cpl_coord_exp; ///< coupling coord exponents (cplcoexp)
uint8_t **cpl_coord_mant; ///< coupling coord mantissas (cplcomant)
uint8_t coeff_shift[AC3_MAX_CHANNELS]; ///< fixed-point coefficient shift values
uint8_t new_rematrixing_strategy; ///< send new rematrixing flags in this block
int num_rematrixing_bands; ///< number of rematrixing bands
uint8_t rematrixing_flags[4]; ///< rematrixing flags
int new_cpl_strategy; ///< send new coupling strategy
int cpl_in_use; ///< coupling in use for this block (cplinu)
uint8_t channel_in_cpl[AC3_MAX_CHANNELS]; ///< channel in coupling (chincpl)
int num_cpl_channels; ///< number of channels in coupling
uint8_t new_cpl_coords; ///< send new coupling coordinates (cplcoe)
uint8_t cpl_master_exp[AC3_MAX_CHANNELS]; ///< coupling coord master exponents (mstrcplco)
int new_snr_offsets; ///< send new SNR offsets
int new_cpl_leak; ///< send new coupling leak info
int end_freq[AC3_MAX_CHANNELS]; ///< end frequency bin (endmant)
} AC3Block;

/**
* AC-3 encoder private context.
*/
typedef struct AC3EncodeContext {
AVClass *av_class; ///< AVClass used for AVOption
AC3EncOptions options; ///< encoding options
PutBitContext pb; ///< bitstream writer context
DSPContext dsp;
AC3DSPContext ac3dsp; ///< AC-3 optimized functions
AC3MDCTContext mdct; ///< MDCT context

AC3Block blocks[AC3_MAX_BLOCKS]; ///< per-block info

int eac3; ///< indicates if this is E-AC-3 vs. AC-3
int bitstream_id; ///< bitstream id (bsid)
int bitstream_mode; ///< bitstream mode (bsmod)

int bit_rate; ///< target bit rate, in bits-per-second
int sample_rate; ///< sampling frequency, in Hz

int frame_size_min; ///< minimum frame size in case rounding is necessary
int frame_size; ///< current frame size in bytes
int frame_size_code; ///< frame size code (frmsizecod)
uint16_t crc_inv[2];
int64_t bits_written; ///< bit count (used to avg. bitrate)
int64_t samples_written; ///< sample count (used to avg. bitrate)

int fbw_channels; ///< number of full-bandwidth channels (nfchans)
int channels; ///< total number of channels (nchans)
int lfe_on; ///< indicates if there is an LFE channel (lfeon)
int lfe_channel; ///< channel index of the LFE channel
int has_center; ///< indicates if there is a center channel
int has_surround; ///< indicates if there are one or more surround channels
int channel_mode; ///< channel mode (acmod)
const uint8_t *channel_map; ///< channel map used to reorder channels

int center_mix_level; ///< center mix level code
int surround_mix_level; ///< surround mix level code
int ltrt_center_mix_level; ///< Lt/Rt center mix level code
int ltrt_surround_mix_level; ///< Lt/Rt surround mix level code
int loro_center_mix_level; ///< Lo/Ro center mix level code
int loro_surround_mix_level; ///< Lo/Ro surround mix level code

int cutoff; ///< user-specified cutoff frequency, in Hz
int bandwidth_code; ///< bandwidth code (0 to 60) (chbwcod)
int start_freq[AC3_MAX_CHANNELS]; ///< start frequency bin (strtmant)
int cpl_end_freq; ///< coupling channel end frequency bin

int cpl_on; ///< coupling turned on for this frame
int cpl_enabled; ///< coupling enabled for all frames
int num_cpl_subbands; ///< number of coupling subbands (ncplsubnd)
int num_cpl_bands; ///< number of coupling bands (ncplbnd)
uint8_t cpl_band_sizes[AC3_MAX_CPL_BANDS]; ///< number of coeffs in each coupling band

int rematrixing_enabled; ///< stereo rematrixing enabled

/* bitrate allocation control */
int slow_gain_code; ///< slow gain code (sgaincod)
int slow_decay_code; ///< slow decay code (sdcycod)
int fast_decay_code; ///< fast decay code (fdcycod)
int db_per_bit_code; ///< dB/bit code (dbpbcod)
int floor_code; ///< floor code (floorcod)
AC3BitAllocParameters bit_alloc; ///< bit allocation parameters
int coarse_snr_offset; ///< coarse SNR offsets (csnroffst)
int fast_gain_code[AC3_MAX_CHANNELS]; ///< fast gain codes (signal-to-mask ratio) (fgaincod)
int fine_snr_offset[AC3_MAX_CHANNELS]; ///< fine SNR offsets (fsnroffst)
int frame_bits_fixed; ///< number of non-coefficient bits for fixed parameters
int frame_bits; ///< all frame bits except exponents and mantissas
int exponent_bits; ///< number of bits used for exponents

SampleType **planar_samples;
uint8_t *bap_buffer;
uint8_t *bap1_buffer;
CoefType *mdct_coef_buffer;
int32_t *fixed_coef_buffer;
uint8_t *exp_buffer;
uint8_t *grouped_exp_buffer;
int16_t *psd_buffer;
int16_t *band_psd_buffer;
int16_t *mask_buffer;
uint16_t *qmant_buffer;
uint8_t *cpl_coord_exp_buffer;
uint8_t *cpl_coord_mant_buffer;

uint8_t exp_strategy[AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]; ///< exponent strategies
uint8_t exp_ref_block[AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]; ///< reference blocks for EXP_REUSE
uint8_t *ref_bap [AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]; ///< bit allocation pointers (bap)
int ref_bap_set; ///< indicates if ref_bap pointers have been set

DECLARE_ALIGNED(32, SampleType, windowed_samples)[AC3_WINDOW_SIZE];
} AC3EncodeContext;

#endif /* AVCODEC_AC3ENC_H */

+ 131
- 0
libavcodec/eac3enc.c View File

@@ -0,0 +1,131 @@
/*
* E-AC-3 encoder
* Copyright (c) 2011 Justin Ruggles <justin.ruggles@gmail.com>
*
* This file is part of Libav.
*
* 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.
*
* 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/

/**
* @file
* E-AC-3 encoder
*/

#define CONFIG_AC3ENC_FLOAT 1
#include "ac3enc.h"
#include "eac3enc.h"

void ff_eac3_set_cpl_states(AC3EncodeContext *s)
{
int ch, blk;
int first_cpl_coords[AC3_MAX_CHANNELS];

/* set first cpl coords */
for (ch = 1; ch <= s->fbw_channels; ch++)
first_cpl_coords[ch] = 1;
for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
AC3Block *block = &s->blocks[blk];
for (ch = 1; ch <= s->fbw_channels; ch++) {
if (block->channel_in_cpl[ch]) {
if (first_cpl_coords[ch]) {
block->new_cpl_coords = 2;
first_cpl_coords[ch] = 0;
}
} else {
first_cpl_coords[ch] = 1;
}
}
}

/* set first cpl leak */
for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
AC3Block *block = &s->blocks[blk];
if (block->cpl_in_use) {
block->new_cpl_leak = 2;
break;
}
}
}


void ff_eac3_output_frame_header(AC3EncodeContext *s)
{
int blk, ch;
AC3EncOptions *opt = &s->options;

put_bits(&s->pb, 16, 0x0b77); /* sync word */

/* BSI header */
put_bits(&s->pb, 2, 0); /* stream type = independent */
put_bits(&s->pb, 3, 0); /* substream id = 0 */
put_bits(&s->pb, 11, (s->frame_size / 2) - 1); /* frame size */
if (s->bit_alloc.sr_shift) {
put_bits(&s->pb, 2, 0x3); /* fscod2 */
put_bits(&s->pb, 2, s->bit_alloc.sr_code); /* sample rate code */
} else {
put_bits(&s->pb, 2, s->bit_alloc.sr_code); /* sample rate code */
put_bits(&s->pb, 2, 0x3); /* number of blocks = 6 */
}
put_bits(&s->pb, 3, s->channel_mode); /* audio coding mode */
put_bits(&s->pb, 1, s->lfe_on); /* LFE channel indicator */
put_bits(&s->pb, 5, s->bitstream_id); /* bitstream id (EAC3=16) */
put_bits(&s->pb, 5, -opt->dialogue_level); /* dialogue normalization level */
put_bits(&s->pb, 1, 0); /* no compression gain */
put_bits(&s->pb, 1, 0); /* no mixing metadata */
/* TODO: mixing metadata */
put_bits(&s->pb, 1, 0); /* no info metadata */
/* TODO: info metadata */
put_bits(&s->pb, 1, 0); /* no additional bit stream info */

/* frame header */
put_bits(&s->pb, 1, 1); /* exponent strategy syntax = each block */
put_bits(&s->pb, 1, 0); /* aht enabled = no */
put_bits(&s->pb, 2, 0); /* snr offset strategy = 1 */
put_bits(&s->pb, 1, 0); /* transient pre-noise processing enabled = no */
put_bits(&s->pb, 1, 0); /* block switch syntax enabled = no */
put_bits(&s->pb, 1, 0); /* dither flag syntax enabled = no */
put_bits(&s->pb, 1, 0); /* bit allocation model syntax enabled = no */
put_bits(&s->pb, 1, 0); /* fast gain codes enabled = no */
put_bits(&s->pb, 1, 0); /* dba syntax enabled = no */
put_bits(&s->pb, 1, 0); /* skip field syntax enabled = no */
put_bits(&s->pb, 1, 0); /* spx enabled = no */
/* coupling strategy use flags */
if (s->channel_mode > AC3_CHMODE_MONO) {
put_bits(&s->pb, 1, s->blocks[0].cpl_in_use);
for (blk = 1; blk < AC3_MAX_BLOCKS; blk++) {
AC3Block *block = &s->blocks[blk];
put_bits(&s->pb, 1, block->new_cpl_strategy);
if (block->new_cpl_strategy)
put_bits(&s->pb, 1, block->cpl_in_use);
}
}
/* exponent strategy */
for (blk = 0; blk < AC3_MAX_BLOCKS; blk++)
for (ch = !s->blocks[blk].cpl_in_use; ch <= s->fbw_channels; ch++)
put_bits(&s->pb, 2, s->exp_strategy[ch][blk]);
if (s->lfe_on) {
for (blk = 0; blk < AC3_MAX_BLOCKS; blk++)
put_bits(&s->pb, 1, s->exp_strategy[s->lfe_channel][blk]);
}
/* E-AC-3 to AC-3 converter exponent strategy (unfortunately not optional...) */
for (ch = 1; ch <= s->fbw_channels; ch++)
put_bits(&s->pb, 5, 0);
/* snr offsets */
put_bits(&s->pb, 6, s->coarse_snr_offset);
put_bits(&s->pb, 4, s->fine_snr_offset[1]);
/* block start info */
put_bits(&s->pb, 1, 0);
}

+ 44
- 0
libavcodec/eac3enc.h View File

@@ -0,0 +1,44 @@
/*
* E-AC-3 encoder
* Copyright (c) 2011 Justin Ruggles <justin.ruggles@gmail.com>
*
* This file is part of Libav.
*
* 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.
*
* 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/

/**
* @file
* E-AC-3 encoder
*/

#ifndef AVCODEC_EAC3ENC_H
#define AVCODEC_EAC3ENC_H

#include "ac3enc.h"

/**
* Set coupling states.
* This determines whether certain flags must be written to the bitstream or
* whether they will be implicitly already known by the decoder.
*/
void ff_eac3_set_cpl_states(AC3EncodeContext *s);

/**
* Write the E-AC-3 frame header to the output bitstream.
*/
void ff_eac3_output_frame_header(AC3EncodeContext *s);

#endif /* AVCODEC_EAC3ENC_H */

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