* The simplest AC-3 encoder.
*/
-//#define DEBUG
//#define ASSERT_LEVEL 2
#include <stdint.h>
#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
+ int16_t *qmant1_ptr, *qmant2_ptr, *qmant4_ptr; ///< mantissa pointers for bap=1,2,4
int mant1_cnt, mant2_cnt, mant4_cnt; ///< mantissa counts for bap=1,2,4
} AC3Mant;
};
-#define OFFSET(param) offsetof(AC3EncodeContext, options.param)
-#define AC3ENC_PARAM (AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM)
-
-#define AC3ENC_TYPE_AC3_FIXED 0
-#define AC3ENC_TYPE_AC3 1
-#define AC3ENC_TYPE_EAC3 2
-
-#if CONFIG_AC3ENC_FLOAT
-#define AC3ENC_TYPE AC3ENC_TYPE_AC3
-#include "ac3enc_opts_template.c"
-static AVClass ac3enc_class = { "AC-3 Encoder", av_default_item_name,
- ac3_options, LIBAVUTIL_VERSION_INT };
-#undef AC3ENC_TYPE
-#define AC3ENC_TYPE AC3ENC_TYPE_EAC3
-#include "ac3enc_opts_template.c"
-static AVClass eac3enc_class = { "E-AC-3 Encoder", av_default_item_name,
- eac3_options, LIBAVUTIL_VERSION_INT };
-#else
-#define AC3ENC_TYPE AC3ENC_TYPE_AC3_FIXED
-#include "ac3enc_opts_template.c"
-static AVClass ac3enc_class = { "Fixed-Point AC-3 Encoder", av_default_item_name,
- ac3fixed_options, LIBAVUTIL_VERSION_INT };
-#endif
-
-
-/* prototypes for functions in ac3enc_fixed.c and ac3enc_float.c */
-
-static av_cold void mdct_end(AC3MDCTContext *mdct);
-
-static av_cold int mdct_init(AVCodecContext *avctx, AC3MDCTContext *mdct,
- int nbits);
-
-static void apply_window(DSPContext *dsp, SampleType *output, const SampleType *input,
- const SampleType *window, unsigned int len);
-
-static int normalize_samples(AC3EncodeContext *s);
-
-static void scale_coefficients(AC3EncodeContext *s);
-
-
/**
* LUT for number of exponent groups.
* exponent_group_tab[coupling][exponent strategy-1][number of coefficients]
/**
* List of supported channel layouts.
*/
-static const int64_t ac3_channel_layouts[] = {
+const int64_t ff_ac3_channel_layouts[19] = {
AV_CH_LAYOUT_MONO,
AV_CH_LAYOUT_STEREO,
AV_CH_LAYOUT_2_1,
* Adjust the frame size to make the average bit rate match the target bit rate.
* This is only needed for 11025, 22050, and 44100 sample rates or any E-AC-3.
*/
-static void adjust_frame_size(AC3EncodeContext *s)
+void ff_ac3_adjust_frame_size(AC3EncodeContext *s)
{
while (s->bits_written >= s->bit_rate && s->samples_written >= s->sample_rate) {
s->bits_written -= s->bit_rate;
}
-/**
- * Deinterleave input samples.
- * Channels are reordered from Libav's default order to AC-3 order.
- */
-static void deinterleave_input_samples(AC3EncodeContext *s,
- const SampleType *samples)
-{
- int ch, i;
-
- /* deinterleave and remap input samples */
- for (ch = 0; ch < s->channels; ch++) {
- const SampleType *sptr;
- int sinc;
-
- /* copy last 256 samples of previous frame to the start of the current frame */
- memcpy(&s->planar_samples[ch][0], &s->planar_samples[ch][AC3_FRAME_SIZE],
- AC3_BLOCK_SIZE * sizeof(s->planar_samples[0][0]));
-
- /* deinterleave */
- sinc = s->channels;
- sptr = samples + s->channel_map[ch];
- for (i = AC3_BLOCK_SIZE; i < AC3_FRAME_SIZE+AC3_BLOCK_SIZE; i++) {
- s->planar_samples[ch][i] = *sptr;
- sptr += sinc;
- }
- }
-}
-
-
-/**
- * Apply the MDCT to input samples to generate frequency coefficients.
- * This applies the KBD window and normalizes the input to reduce precision
- * loss due to fixed-point calculations.
- */
-static void apply_mdct(AC3EncodeContext *s)
-{
- int blk, ch;
-
- for (ch = 0; ch < s->channels; ch++) {
- for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
- AC3Block *block = &s->blocks[blk];
- const SampleType *input_samples = &s->planar_samples[ch][blk * AC3_BLOCK_SIZE];
-
- apply_window(&s->dsp, s->windowed_samples, input_samples, s->mdct.window, AC3_WINDOW_SIZE);
-
- block->coeff_shift[ch+1] = normalize_samples(s);
-
- s->mdct.fft.mdct_calcw(&s->mdct.fft, block->mdct_coef[ch+1],
- s->windowed_samples);
- }
- }
-}
-
-
-static void compute_coupling_strategy(AC3EncodeContext *s)
+void ff_ac3_compute_coupling_strategy(AC3EncodeContext *s)
{
int blk, ch;
int got_cpl_snr;
}
-/**
- * Calculate a single coupling coordinate.
- */
-static inline float calc_cpl_coord(float energy_ch, float energy_cpl)
-{
- float coord = 0.125;
- if (energy_cpl > 0)
- coord *= sqrtf(energy_ch / energy_cpl);
- return coord;
-}
-
-
-/**
- * Calculate coupling channel and coupling coordinates.
- * TODO: Currently this is only used for the floating-point encoder. I was
- * able to make it work for the fixed-point encoder, but quality was
- * generally lower in most cases than not using coupling. If a more
- * adaptive coupling strategy were to be implemented it might be useful
- * at that time to use coupling for the fixed-point encoder as well.
- */
-static void apply_channel_coupling(AC3EncodeContext *s)
-{
-#if CONFIG_AC3ENC_FLOAT
- LOCAL_ALIGNED_16(float, cpl_coords, [AC3_MAX_BLOCKS], [AC3_MAX_CHANNELS][16]);
- LOCAL_ALIGNED_16(int32_t, fixed_cpl_coords, [AC3_MAX_BLOCKS], [AC3_MAX_CHANNELS][16]);
- int blk, ch, bnd, i, j;
- CoefSumType energy[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][16] = {{{0}}};
- int num_cpl_coefs = s->num_cpl_subbands * 12;
-
- memset(cpl_coords, 0, AC3_MAX_BLOCKS * sizeof(*cpl_coords));
- memset(fixed_cpl_coords, 0, AC3_MAX_BLOCKS * sizeof(*fixed_cpl_coords));
-
- /* calculate coupling channel from fbw channels */
- for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
- AC3Block *block = &s->blocks[blk];
- CoefType *cpl_coef = &block->mdct_coef[CPL_CH][s->start_freq[CPL_CH]];
- if (!block->cpl_in_use)
- continue;
- memset(cpl_coef-1, 0, (num_cpl_coefs+4) * sizeof(*cpl_coef));
- for (ch = 1; ch <= s->fbw_channels; ch++) {
- CoefType *ch_coef = &block->mdct_coef[ch][s->start_freq[CPL_CH]];
- if (!block->channel_in_cpl[ch])
- continue;
- for (i = 0; i < num_cpl_coefs; i++)
- cpl_coef[i] += ch_coef[i];
- }
- /* note: coupling start bin % 4 will always be 1 and num_cpl_coefs
- will always be a multiple of 12, so we need to subtract 1 from
- the start and add 4 to the length when using optimized
- functions which require 16-byte alignment. */
-
- /* coefficients must be clipped to +/- 1.0 in order to be encoded */
- s->dsp.vector_clipf(cpl_coef-1, cpl_coef-1, -1.0f, 1.0f, num_cpl_coefs+4);
-
- /* scale coupling coefficients from float to 24-bit fixed-point */
- s->ac3dsp.float_to_fixed24(&block->fixed_coef[CPL_CH][s->start_freq[CPL_CH]-1],
- cpl_coef-1, num_cpl_coefs+4);
- }
-
- /* calculate energy in each band in coupling channel and each fbw channel */
- /* TODO: possibly use SIMD to speed up energy calculation */
- bnd = 0;
- i = s->start_freq[CPL_CH];
- while (i < s->cpl_end_freq) {
- int band_size = s->cpl_band_sizes[bnd];
- for (ch = CPL_CH; ch <= s->fbw_channels; ch++) {
- for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
- AC3Block *block = &s->blocks[blk];
- if (!block->cpl_in_use || (ch > CPL_CH && !block->channel_in_cpl[ch]))
- continue;
- for (j = 0; j < band_size; j++) {
- CoefType v = block->mdct_coef[ch][i+j];
- MAC_COEF(energy[blk][ch][bnd], v, v);
- }
- }
- }
- i += band_size;
- bnd++;
- }
-
- /* determine which blocks to send new coupling coordinates for */
- for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
- AC3Block *block = &s->blocks[blk];
- AC3Block *block0 = blk ? &s->blocks[blk-1] : NULL;
- int new_coords = 0;
- CoefSumType coord_diff[AC3_MAX_CHANNELS] = {0,};
-
- if (block->cpl_in_use) {
- /* calculate coupling coordinates for all blocks and calculate the
- average difference between coordinates in successive blocks */
- for (ch = 1; ch <= s->fbw_channels; ch++) {
- if (!block->channel_in_cpl[ch])
- continue;
-
- for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
- cpl_coords[blk][ch][bnd] = calc_cpl_coord(energy[blk][ch][bnd],
- energy[blk][CPL_CH][bnd]);
- if (blk > 0 && block0->cpl_in_use &&
- block0->channel_in_cpl[ch]) {
- coord_diff[ch] += fabs(cpl_coords[blk-1][ch][bnd] -
- cpl_coords[blk ][ch][bnd]);
- }
- }
- coord_diff[ch] /= s->num_cpl_bands;
- }
-
- /* send new coordinates if this is the first block, if previous
- * block did not use coupling but this block does, the channels
- * using coupling has changed from the previous block, or the
- * coordinate difference from the last block for any channel is
- * greater than a threshold value. */
- if (blk == 0) {
- new_coords = 1;
- } else if (!block0->cpl_in_use) {
- new_coords = 1;
- } else {
- for (ch = 1; ch <= s->fbw_channels; ch++) {
- if (block->channel_in_cpl[ch] && !block0->channel_in_cpl[ch]) {
- new_coords = 1;
- break;
- }
- }
- if (!new_coords) {
- for (ch = 1; ch <= s->fbw_channels; ch++) {
- if (block->channel_in_cpl[ch] && coord_diff[ch] > 0.04) {
- new_coords = 1;
- break;
- }
- }
- }
- }
- }
- block->new_cpl_coords = new_coords;
- }
-
- /* calculate final coupling coordinates, taking into account reusing of
- coordinates in successive blocks */
- for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
- blk = 0;
- while (blk < AC3_MAX_BLOCKS) {
- int blk1;
- CoefSumType energy_cpl;
- AC3Block *block = &s->blocks[blk];
-
- if (!block->cpl_in_use) {
- blk++;
- continue;
- }
-
- energy_cpl = energy[blk][CPL_CH][bnd];
- blk1 = blk+1;
- while (!s->blocks[blk1].new_cpl_coords && blk1 < AC3_MAX_BLOCKS) {
- if (s->blocks[blk1].cpl_in_use)
- energy_cpl += energy[blk1][CPL_CH][bnd];
- blk1++;
- }
-
- for (ch = 1; ch <= s->fbw_channels; ch++) {
- CoefType energy_ch;
- if (!block->channel_in_cpl[ch])
- continue;
- energy_ch = energy[blk][ch][bnd];
- blk1 = blk+1;
- while (!s->blocks[blk1].new_cpl_coords && blk1 < AC3_MAX_BLOCKS) {
- if (s->blocks[blk1].cpl_in_use)
- energy_ch += energy[blk1][ch][bnd];
- blk1++;
- }
- cpl_coords[blk][ch][bnd] = calc_cpl_coord(energy_ch, energy_cpl);
- }
- blk = blk1;
- }
- }
-
- /* calculate exponents/mantissas for coupling coordinates */
- for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
- AC3Block *block = &s->blocks[blk];
- if (!block->cpl_in_use || !block->new_cpl_coords)
- continue;
-
- s->ac3dsp.float_to_fixed24(fixed_cpl_coords[blk][1],
- cpl_coords[blk][1],
- s->fbw_channels * 16);
- s->ac3dsp.extract_exponents(block->cpl_coord_exp[1],
- fixed_cpl_coords[blk][1],
- s->fbw_channels * 16);
-
- for (ch = 1; ch <= s->fbw_channels; ch++) {
- int bnd, min_exp, max_exp, master_exp;
-
- /* determine master exponent */
- min_exp = max_exp = block->cpl_coord_exp[ch][0];
- for (bnd = 1; bnd < s->num_cpl_bands; bnd++) {
- int exp = block->cpl_coord_exp[ch][bnd];
- min_exp = FFMIN(exp, min_exp);
- max_exp = FFMAX(exp, max_exp);
- }
- master_exp = ((max_exp - 15) + 2) / 3;
- master_exp = FFMAX(master_exp, 0);
- while (min_exp < master_exp * 3)
- master_exp--;
- for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
- block->cpl_coord_exp[ch][bnd] = av_clip(block->cpl_coord_exp[ch][bnd] -
- master_exp * 3, 0, 15);
- }
- block->cpl_master_exp[ch] = master_exp;
-
- /* quantize mantissas */
- for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
- int cpl_exp = block->cpl_coord_exp[ch][bnd];
- int cpl_mant = (fixed_cpl_coords[blk][ch][bnd] << (5 + cpl_exp + master_exp * 3)) >> 24;
- if (cpl_exp == 15)
- cpl_mant >>= 1;
- else
- cpl_mant -= 16;
-
- block->cpl_coord_mant[ch][bnd] = cpl_mant;
- }
- }
- }
-
- 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;
- }
- }
- }
-#endif /* CONFIG_AC3ENC_FLOAT */
-}
-
-
-/**
- * Determine rematrixing flags for each block and band.
- */
-static void compute_rematrixing_strategy(AC3EncodeContext *s)
-{
- int nb_coefs;
- int blk, bnd, i;
- AC3Block *block, *block0;
-
- if (s->channel_mode != AC3_CHMODE_STEREO)
- return;
-
- for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
- block = &s->blocks[blk];
- block->new_rematrixing_strategy = !blk;
-
- if (!s->rematrixing_enabled) {
- block0 = block;
- continue;
- }
-
- block->num_rematrixing_bands = 4;
- if (block->cpl_in_use) {
- block->num_rematrixing_bands -= (s->start_freq[CPL_CH] <= 61);
- block->num_rematrixing_bands -= (s->start_freq[CPL_CH] == 37);
- if (blk && block->num_rematrixing_bands != block0->num_rematrixing_bands)
- block->new_rematrixing_strategy = 1;
- }
- nb_coefs = FFMIN(block->end_freq[1], block->end_freq[2]);
-
- for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++) {
- /* calculate calculate sum of squared coeffs for one band in one block */
- int start = ff_ac3_rematrix_band_tab[bnd];
- int end = FFMIN(nb_coefs, ff_ac3_rematrix_band_tab[bnd+1]);
- CoefSumType sum[4] = {0,};
- for (i = start; i < end; i++) {
- CoefType lt = block->mdct_coef[1][i];
- CoefType rt = block->mdct_coef[2][i];
- CoefType md = lt + rt;
- CoefType sd = lt - rt;
- MAC_COEF(sum[0], lt, lt);
- MAC_COEF(sum[1], rt, rt);
- MAC_COEF(sum[2], md, md);
- MAC_COEF(sum[3], sd, sd);
- }
-
- /* compare sums to determine if rematrixing will be used for this band */
- if (FFMIN(sum[2], sum[3]) < FFMIN(sum[0], sum[1]))
- block->rematrixing_flags[bnd] = 1;
- else
- block->rematrixing_flags[bnd] = 0;
-
- /* determine if new rematrixing flags will be sent */
- if (blk &&
- block->rematrixing_flags[bnd] != block0->rematrixing_flags[bnd]) {
- block->new_rematrixing_strategy = 1;
- }
- }
- block0 = block;
- }
-}
-
-
/**
* Apply stereo rematrixing to coefficients based on rematrixing flags.
*/
-static void apply_rematrixing(AC3EncodeContext *s)
+void ff_ac3_apply_rematrixing(AC3EncodeContext *s)
{
int nb_coefs;
int blk, bnd, i;
/**
* Extract exponents from the MDCT coefficients.
- * This takes into account the normalization that was done to the input samples
- * by adjusting the exponents by the exponent shift values.
*/
static void extract_exponents(AC3EncodeContext *s)
{
* Extract exponents from MDCT coefficients, calculate exponent strategies,
* and encode final exponents.
*/
-static void process_exponents(AC3EncodeContext *s)
+void ff_ac3_process_exponents(AC3EncodeContext *s)
{
extract_exponents(s);
}
-/**
- * Downgrade exponent strategies to reduce the bits used by the exponents.
- * This is a fallback for when bit allocation fails with the normal exponent
- * strategies. Each time this function is run it only downgrades the
- * strategy in 1 channel of 1 block.
- * @return non-zero if downgrade was unsuccessful
- */
-static int downgrade_exponents(AC3EncodeContext *s)
-{
- int ch, blk;
-
- for (blk = AC3_MAX_BLOCKS-1; blk >= 0; blk--) {
- for (ch = !s->blocks[blk].cpl_in_use; ch <= s->fbw_channels; ch++) {
- if (s->exp_strategy[ch][blk] == EXP_D15) {
- s->exp_strategy[ch][blk] = EXP_D25;
- return 0;
- }
- }
- }
- for (blk = AC3_MAX_BLOCKS-1; blk >= 0; blk--) {
- for (ch = !s->blocks[blk].cpl_in_use; ch <= s->fbw_channels; ch++) {
- if (s->exp_strategy[ch][blk] == EXP_D25) {
- s->exp_strategy[ch][blk] = EXP_D45;
- return 0;
- }
- }
- }
- /* block 0 cannot reuse exponents, so only downgrade D45 to REUSE if
- the block number > 0 */
- for (blk = AC3_MAX_BLOCKS-1; blk > 0; blk--) {
- for (ch = !s->blocks[blk].cpl_in_use; ch <= s->fbw_channels; ch++) {
- if (s->exp_strategy[ch][blk] > EXP_REUSE) {
- s->exp_strategy[ch][blk] = EXP_REUSE;
- return 0;
- }
- }
- }
- return -1;
-}
-
-
/**
* Perform bit allocation search.
* Finds the SNR offset value that maximizes quality and fits in the specified
* frame size. Output is the SNR offset and a set of bit allocation pointers
* used to quantize the mantissas.
*/
-static int compute_bit_allocation(AC3EncodeContext *s)
+int ff_ac3_compute_bit_allocation(AC3EncodeContext *s)
{
- int ret;
-
count_frame_bits(s);
bit_alloc_masking(s);
- ret = cbr_bit_allocation(s);
- while (ret) {
- /* fallback 1: disable channel coupling */
- if (s->cpl_on) {
- s->cpl_on = 0;
- compute_coupling_strategy(s);
- compute_rematrixing_strategy(s);
- apply_rematrixing(s);
- process_exponents(s);
- ret = compute_bit_allocation(s);
- continue;
- }
-
- /* fallback 2: downgrade exponents */
- if (!downgrade_exponents(s)) {
- extract_exponents(s);
- encode_exponents(s);
- group_exponents(s);
- ret = compute_bit_allocation(s);
- continue;
- }
-
- /* fallbacks were not enough... */
- break;
- }
-
- return ret;
+ return cbr_bit_allocation(s);
}
*/
static inline int asym_quant(int c, int e, int qbits)
{
- int lshift, m, v;
+ int m;
- lshift = e + qbits - 24;
- if (lshift >= 0)
- v = c << lshift;
- else
- v = c >> (-lshift);
- /* rounding */
- v = (v + 1) >> 1;
+ c = (((c << e) >> (24 - qbits)) + 1) >> 1;
m = (1 << (qbits-1));
- if (v >= m)
- v = m - 1;
- av_assert2(v >= -m);
- return v & ((1 << qbits)-1);
+ if (c >= m)
+ c = m - 1;
+ av_assert2(c >= -m);
+ return c;
}
*/
static void quantize_mantissas_blk_ch(AC3Mant *s, int32_t *fixed_coef,
uint8_t *exp, uint8_t *bap,
- uint16_t *qmant, int start_freq,
+ int16_t *qmant, int start_freq,
int end_freq)
{
int i;
/**
* Quantize mantissas using coefficients, exponents, and bit allocation pointers.
*/
-static void quantize_mantissas(AC3EncodeContext *s)
+void ff_ac3_quantize_mantissas(AC3EncodeContext *s)
{
int blk, ch, ch0=0, got_cpl;
}
-/**
- * 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.
*/
q = block->qmant[ch][i];
b = s->ref_bap[ch][blk][i];
switch (b) {
- case 0: break;
- case 1: if (q != 128) put_bits(&s->pb, 5, q); break;
- case 2: if (q != 128) put_bits(&s->pb, 7, q); break;
- case 3: put_bits(&s->pb, 3, q); break;
- case 4: if (q != 128) put_bits(&s->pb, 7, q); break;
- case 14: put_bits(&s->pb, 14, q); break;
- case 15: put_bits(&s->pb, 16, q); break;
- default: put_bits(&s->pb, b-1, q); break;
+ case 0: break;
+ case 1: if (q != 128) put_bits (&s->pb, 5, q); break;
+ case 2: if (q != 128) put_bits (&s->pb, 7, q); break;
+ case 3: put_sbits(&s->pb, 3, q); break;
+ case 4: if (q != 128) put_bits (&s->pb, 7, q); break;
+ case 14: put_sbits(&s->pb, 14, q); break;
+ case 15: put_sbits(&s->pb, 16, q); break;
+ default: put_sbits(&s->pb, b-1, q); break;
}
}
if (ch == CPL_CH)
/**
* Write the frame to the output bitstream.
*/
-static void output_frame(AC3EncodeContext *s, unsigned char *frame)
+void ff_ac3_output_frame(AC3EncodeContext *s, unsigned char *frame)
{
int blk;
init_put_bits(&s->pb, frame, AC3_MAX_CODED_FRAME_SIZE);
- if (s->eac3)
- eac3_output_frame_header(s);
- else
- ac3_output_frame_header(s);
+ s->output_frame_header(s);
for (blk = 0; blk < AC3_MAX_BLOCKS; blk++)
output_audio_block(s, blk);
}
-static void dprint_options(AVCodecContext *avctx)
+static void dprint_options(AC3EncodeContext *s)
{
#ifdef DEBUG
- AC3EncodeContext *s = avctx->priv_data;
+ AVCodecContext *avctx = s->avctx;
AC3EncOptions *opt = &s->options;
char strbuf[32];
* Validate metadata options as set by AVOption system.
* These values can optionally be changed per-frame.
*/
-static int validate_metadata(AVCodecContext *avctx)
+int ff_ac3_validate_metadata(AC3EncodeContext *s)
{
- AC3EncodeContext *s = avctx->priv_data;
+ AVCodecContext *avctx = s->avctx;
AC3EncOptions *opt = &s->options;
/* validate mixing levels */
}
-/**
- * Encode a single AC-3 frame.
- */
-static int ac3_encode_frame(AVCodecContext *avctx, unsigned char *frame,
- int buf_size, void *data)
-{
- AC3EncodeContext *s = avctx->priv_data;
- const SampleType *samples = data;
- int ret;
-
- if (!s->eac3 && s->options.allow_per_frame_metadata) {
- ret = validate_metadata(avctx);
- if (ret)
- return ret;
- }
-
- if (s->bit_alloc.sr_code == 1 || s->eac3)
- adjust_frame_size(s);
-
- deinterleave_input_samples(s, samples);
-
- apply_mdct(s);
-
- scale_coefficients(s);
-
- s->cpl_on = s->cpl_enabled;
- compute_coupling_strategy(s);
-
- if (s->cpl_on)
- apply_channel_coupling(s);
-
- compute_rematrixing_strategy(s);
-
- apply_rematrixing(s);
-
- process_exponents(s);
-
- ret = compute_bit_allocation(s);
- if (ret) {
- av_log(avctx, AV_LOG_ERROR, "Bit allocation failed. Try increasing the bitrate.\n");
- return ret;
- }
-
- quantize_mantissas(s);
-
- output_frame(s, frame);
-
- return s->frame_size;
-}
-
-
/**
* Finalize encoding and free any memory allocated by the encoder.
*/
-static av_cold int ac3_encode_close(AVCodecContext *avctx)
+av_cold int ff_ac3_encode_close(AVCodecContext *avctx)
{
int blk, ch;
AC3EncodeContext *s = avctx->priv_data;
+ av_freep(&s->windowed_samples);
for (ch = 0; ch < s->channels; ch++)
av_freep(&s->planar_samples[ch]);
av_freep(&s->planar_samples);
av_freep(&s->band_psd_buffer);
av_freep(&s->mask_buffer);
av_freep(&s->qmant_buffer);
+ av_freep(&s->cpl_coord_exp_buffer);
+ av_freep(&s->cpl_coord_mant_buffer);
for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
AC3Block *block = &s->blocks[blk];
av_freep(&block->mdct_coef);
av_freep(&block->band_psd);
av_freep(&block->mask);
av_freep(&block->qmant);
+ av_freep(&block->cpl_coord_exp);
+ av_freep(&block->cpl_coord_mant);
}
- mdct_end(&s->mdct);
+ s->mdct_end(s);
av_freep(&avctx->coded_frame);
return 0;
}
-static av_cold int validate_options(AVCodecContext *avctx, AC3EncodeContext *s)
+static av_cold int validate_options(AC3EncodeContext *s)
{
+ AVCodecContext *avctx = s->avctx;
int i, ret, max_sr;
/* validate channel layout */
}
if (!s->eac3) {
- ret = validate_metadata(avctx);
+ ret = ff_ac3_validate_metadata(s);
if (ret)
return ret;
}
(s->channel_mode == AC3_CHMODE_STEREO);
s->cpl_enabled = s->options.channel_coupling &&
- s->channel_mode >= AC3_CHMODE_STEREO &&
- CONFIG_AC3ENC_FLOAT;
+ s->channel_mode >= AC3_CHMODE_STEREO && !s->fixed_point;
return 0;
}
}
-static av_cold int allocate_buffers(AVCodecContext *avctx)
+static av_cold int allocate_buffers(AC3EncodeContext *s)
{
+ AVCodecContext *avctx = s->avctx;
int blk, ch;
- AC3EncodeContext *s = avctx->priv_data;
int channels = s->channels + 1; /* includes coupling channel */
- FF_ALLOC_OR_GOTO(avctx, s->planar_samples, s->channels * sizeof(*s->planar_samples),
- alloc_fail);
- for (ch = 0; ch < s->channels; ch++) {
- FF_ALLOCZ_OR_GOTO(avctx, s->planar_samples[ch],
- (AC3_FRAME_SIZE+AC3_BLOCK_SIZE) * sizeof(**s->planar_samples),
- alloc_fail);
- }
+ if (s->allocate_sample_buffers(s))
+ goto alloc_fail;
+
FF_ALLOC_OR_GOTO(avctx, s->bap_buffer, AC3_MAX_BLOCKS * channels *
AC3_MAX_COEFS * sizeof(*s->bap_buffer), alloc_fail);
FF_ALLOC_OR_GOTO(avctx, s->bap1_buffer, AC3_MAX_BLOCKS * channels *
}
}
- if (CONFIG_AC3ENC_FLOAT) {
+ if (!s->fixed_point) {
FF_ALLOCZ_OR_GOTO(avctx, s->fixed_coef_buffer, AC3_MAX_BLOCKS * channels *
AC3_MAX_COEFS * sizeof(*s->fixed_coef_buffer), alloc_fail);
for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
/**
* Initialize the encoder.
*/
-static av_cold int ac3_encode_init(AVCodecContext *avctx)
+av_cold int ff_ac3_encode_init(AVCodecContext *avctx)
{
AC3EncodeContext *s = avctx->priv_data;
int ret, frame_size_58;
+ s->avctx = avctx;
+
s->eac3 = avctx->codec_id == CODEC_ID_EAC3;
avctx->frame_size = AC3_FRAME_SIZE;
ff_ac3_common_init();
- ret = validate_options(avctx, s);
+ ret = validate_options(s);
if (ret)
return ret;
s->crc_inv[1] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);
}
+ /* set function pointers */
+ if (CONFIG_AC3_FIXED_ENCODER && s->fixed_point) {
+ s->mdct_end = ff_ac3_fixed_mdct_end;
+ s->mdct_init = ff_ac3_fixed_mdct_init;
+ s->allocate_sample_buffers = ff_ac3_fixed_allocate_sample_buffers;
+ } else if (CONFIG_AC3_ENCODER || CONFIG_EAC3_ENCODER) {
+ s->mdct_end = ff_ac3_float_mdct_end;
+ s->mdct_init = ff_ac3_float_mdct_init;
+ s->allocate_sample_buffers = ff_ac3_float_allocate_sample_buffers;
+ }
+ if (CONFIG_EAC3_ENCODER && s->eac3)
+ s->output_frame_header = ff_eac3_output_frame_header;
+ else
+ s->output_frame_header = ac3_output_frame_header;
+
set_bandwidth(s);
exponent_init(s);
bit_alloc_init(s);
- ret = mdct_init(avctx, &s->mdct, 9);
+ ret = s->mdct_init(s);
if (ret)
goto init_fail;
- ret = allocate_buffers(avctx);
+ ret = allocate_buffers(s);
if (ret)
goto init_fail;
dsputil_init(&s->dsp, avctx);
ff_ac3dsp_init(&s->ac3dsp, avctx->flags & CODEC_FLAG_BITEXACT);
- dprint_options(avctx);
+ dprint_options(s);
return 0;
init_fail:
- ac3_encode_close(avctx);
+ ff_ac3_encode_close(avctx);
return ret;
}
projects / ffmpeg / blobdiff