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cosmetics: rename all AC3DecodeContext variables from ctx to s

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Originally committed as revision 11355 to svn://svn.ffmpeg.org/ffmpeg/trunk
pull/126/head
Justin Ruggles 17 years ago
parent 23c8cb89c9
commit d802d7ca12
1 changed files with 251 additions and 251 deletions
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  1. 502
      libavcodec/ac3dec.c

502
libavcodec/ac3dec.c
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@ -291,24 +291,24 @@ static void ac3_tables_init(void)
*/
static int ac3_decode_init(AVCodecContext *avctx)
{
AC3DecodeContext *ctx = avctx->priv_data;
ctx->avctx = avctx;
AC3DecodeContext *s = avctx->priv_data;
s->avctx = avctx;
ac3_common_init();
ac3_tables_init();
ff_mdct_init(&ctx->imdct_256, 8, 1);
ff_mdct_init(&ctx->imdct_512, 9, 1);
ac3_window_init(ctx->window);
dsputil_init(&ctx->dsp, avctx);
av_init_random(0, &ctx->dith_state);
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(ctx->dsp.float_to_int16 == ff_float_to_int16_c) {
ctx->add_bias = 385.0f;
ctx->mul_bias = 1.0f;
if(s->dsp.float_to_int16 == ff_float_to_int16_c) {
s->add_bias = 385.0f;
s->mul_bias = 1.0f;
} else {
ctx->add_bias = 0.0f;
ctx->mul_bias = 32767.0f;
s->add_bias = 0.0f;
s->mul_bias = 32767.0f;
}
return 0;
@ -319,10 +319,10 @@ static int ac3_decode_init(AVCodecContext *avctx)
* GetBitContext within AC3DecodeContext must point to
* start of the synchronized ac3 bitstream.
*/
static int ac3_parse_header(AC3DecodeContext *ctx)
static int ac3_parse_header(AC3DecodeContext *s)
{
AC3HeaderInfo hdr;
GetBitContext *gbc = &ctx->gbc;
GetBitContext *gbc = &s->gbc;
float center_mix_level, surround_mix_level;
int err, i;
@ -331,42 +331,42 @@ static int ac3_parse_header(AC3DecodeContext *ctx)
return err;
/* get decoding parameters from header info */
ctx->bit_alloc_params.sr_code = hdr.sr_code;
ctx->channel_mode = hdr.channel_mode;
s->bit_alloc_params.sr_code = hdr.sr_code;
s->channel_mode = hdr.channel_mode;
center_mix_level = gain_levels[center_levels[hdr.center_mix_level]];
surround_mix_level = gain_levels[surround_levels[hdr.surround_mix_level]];
ctx->lfe_on = hdr.lfe_on;
ctx->bit_alloc_params.sr_shift = hdr.sr_shift;
ctx->sampling_rate = hdr.sample_rate;
ctx->bit_rate = hdr.bit_rate;
ctx->channels = hdr.channels;
ctx->fbw_channels = ctx->channels - ctx->lfe_on;
ctx->lfe_ch = ctx->fbw_channels + 1;
ctx->frame_size = hdr.frame_size;
s->lfe_on = hdr.lfe_on;
s->bit_alloc_params.sr_shift = hdr.sr_shift;
s->sampling_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 */
ctx->out_channels = ctx->channels;
ctx->output_mode = ctx->channel_mode;
if(ctx->lfe_on)
ctx->output_mode |= AC3_OUTPUT_LFEON;
s->out_channels = s->channels;
s->output_mode = s->channel_mode;
if(s->lfe_on)
s->output_mode |= AC3_OUTPUT_LFEON;
/* 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(ctx->channel_mode == AC3_CHMODE_STEREO) {
if(s->channel_mode == AC3_CHMODE_STEREO) {
skip_bits(gbc, 2); // skip dsurmod
} else {
if((ctx->channel_mode & 1) && ctx->channel_mode != AC3_CHMODE_MONO)
if((s->channel_mode & 1) && s->channel_mode != AC3_CHMODE_MONO)
skip_bits(gbc, 2); // skip cmixlev
if(ctx->channel_mode & 4)
if(s->channel_mode & 4)
skip_bits(gbc, 2); // skip surmixlev
}
skip_bits1(gbc); // skip lfeon
/* read the rest of the bsi. read twice for dual mono mode. */
i = !(ctx->channel_mode);
i = !(s->channel_mode);
do {
skip_bits(gbc, 5); // skip dialog normalization
if (get_bits1(gbc))
@ -396,20 +396,20 @@ static int ac3_parse_header(AC3DecodeContext *ctx)
/* set stereo downmixing coefficients
reference: Section 7.8.2 Downmixing Into Two Channels */
for(i=0; i<ctx->fbw_channels; i++) {
ctx->downmix_coeffs[i][0] = gain_levels[ac3_default_coeffs[ctx->channel_mode][i][0]];
ctx->downmix_coeffs[i][1] = gain_levels[ac3_default_coeffs[ctx->channel_mode][i][1]];
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(ctx->channel_mode > 1 && ctx->channel_mode & 1) {
ctx->downmix_coeffs[1][0] = ctx->downmix_coeffs[1][1] = center_mix_level;
if(s->channel_mode > 1 && s->channel_mode & 1) {
s->downmix_coeffs[1][0] = s->downmix_coeffs[1][1] = center_mix_level;
}
if(ctx->channel_mode == AC3_CHMODE_2F1R || ctx->channel_mode == AC3_CHMODE_3F1R) {
int nf = ctx->channel_mode - 2;
ctx->downmix_coeffs[nf][0] = ctx->downmix_coeffs[nf][1] = surround_mix_level * LEVEL_MINUS_3DB;
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] = surround_mix_level * LEVEL_MINUS_3DB;
}
if(ctx->channel_mode == AC3_CHMODE_2F2R || ctx->channel_mode == AC3_CHMODE_3F2R) {
int nf = ctx->channel_mode - 4;
ctx->downmix_coeffs[nf][0] = ctx->downmix_coeffs[nf+1][1] = surround_mix_level;
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] = surround_mix_level;
}
return 0;
@ -450,23 +450,23 @@ static void decode_exponents(GetBitContext *gbc, int exp_strategy, int ngrps,
* range using the coupling coefficients and coupling coordinates.
* reference: Section 7.4.3 Coupling Coordinate Format
*/
static void uncouple_channels(AC3DecodeContext *ctx)
static void uncouple_channels(AC3DecodeContext *s)
{
int i, j, ch, bnd, subbnd;
subbnd = -1;
i = ctx->start_freq[CPL_CH];
for(bnd=0; bnd<ctx->num_cpl_bands; bnd++) {
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<=ctx->fbw_channels; ch++) {
if(ctx->channel_in_cpl[ch])
ctx->transform_coeffs[ch][i] = ctx->transform_coeffs[CPL_CH][i] * ctx->cpl_coords[ch][bnd] * 8.0f;
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;
}
i++;
}
} while(ctx->cpl_band_struct[subbnd]);
} while(s->cpl_band_struct[subbnd]);
}
}
@ -486,25 +486,25 @@ typedef struct {
* Get the transform coefficients for a particular channel
* reference: Section 7.3 Quantization and Decoding of Mantissas
*/
static int get_transform_coeffs_ch(AC3DecodeContext *ctx, int ch_index, mant_groups *m)
static int get_transform_coeffs_ch(AC3DecodeContext *s, int ch_index, mant_groups *m)
{
GetBitContext *gbc = &ctx->gbc;
GetBitContext *gbc = &s->gbc;
int i, gcode, tbap, start, end;
uint8_t *exps;
uint8_t *bap;
float *coeffs;
exps = ctx->dexps[ch_index];
bap = ctx->bap[ch_index];
coeffs = ctx->transform_coeffs[ch_index];
start = ctx->start_freq[ch_index];
end = ctx->end_freq[ch_index];
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(&ctx->dith_state) & 0xFFFF) / 65535.0f) - 0.5f;
coeffs[i] = ((av_random(&s->dith_state) & 0xFFFF) / 65535.0f) - 0.5f;
break;
case 1:
@ -562,27 +562,27 @@ static int get_transform_coeffs_ch(AC3DecodeContext *ctx, int ch_index, mant_gro
* Remove random dithering from coefficients with zero-bit mantissas
* reference: Section 7.3.4 Dither for Zero Bit Mantissas (bap=0)
*/
static void remove_dithering(AC3DecodeContext *ctx) {
static void remove_dithering(AC3DecodeContext *s) {
int ch, i;
int end=0;
float *coeffs;
uint8_t *bap;
for(ch=1; ch<=ctx->fbw_channels; ch++) {
if(!ctx->dither_flag[ch]) {
coeffs = ctx->transform_coeffs[ch];
bap = ctx->bap[ch];
if(ctx->channel_in_cpl[ch])
end = ctx->start_freq[CPL_CH];
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 = ctx->end_freq[ch];
end = s->end_freq[ch];
for(i=0; i<end; i++) {
if(bap[i] == 0)
coeffs[i] = 0.0f;
}
if(ctx->channel_in_cpl[ch]) {
bap = ctx->bap[CPL_CH];
for(; i<ctx->end_freq[CPL_CH]; i++) {
if(s->channel_in_cpl[ch]) {
bap = s->bap[CPL_CH];
for(; i<s->end_freq[CPL_CH]; i++) {
if(bap[i] == 0)
coeffs[i] = 0.0f;
}
@ -594,7 +594,7 @@ static void remove_dithering(AC3DecodeContext *ctx) {
/**
* Get the transform coefficients.
*/
static int get_transform_coeffs(AC3DecodeContext * ctx)
static int get_transform_coeffs(AC3DecodeContext *s)
{
int ch, end;
int got_cplchan = 0;
@ -602,33 +602,33 @@ static int get_transform_coeffs(AC3DecodeContext * ctx)
m.b1ptr = m.b2ptr = m.b4ptr = 3;
for (ch = 1; ch <= ctx->channels; ch++) {
for (ch = 1; ch <= s->channels; ch++) {
/* transform coefficients for full-bandwidth channel */
if (get_transform_coeffs_ch(ctx, ch, &m))
if (get_transform_coeffs_ch(s, ch, &m))
return -1;
/* tranform coefficients for coupling channel come right after the
coefficients for the first coupled channel*/
if (ctx->channel_in_cpl[ch]) {
if (s->channel_in_cpl[ch]) {
if (!got_cplchan) {
if (get_transform_coeffs_ch(ctx, CPL_CH, &m)) {
av_log(ctx->avctx, AV_LOG_ERROR, "error in decoupling channels\n");
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(ctx);
uncouple_channels(s);
got_cplchan = 1;
}
end = ctx->end_freq[CPL_CH];
end = s->end_freq[CPL_CH];
} else {
end = ctx->end_freq[ch];
end = s->end_freq[ch];
}
do
ctx->transform_coeffs[ch][end] = 0;
s->transform_coeffs[ch][end] = 0;
while(++end < 256);
}
/* if any channel doesn't use dithering, zero appropriate coefficients */
if(!ctx->dither_all)
remove_dithering(ctx);
if(!s->dither_all)
remove_dithering(s);
return 0;
}
@ -637,22 +637,22 @@ static int get_transform_coeffs(AC3DecodeContext * ctx)
* Stereo rematrixing.
* reference: Section 7.5.4 Rematrixing : Decoding Technique
*/
static void do_rematrixing(AC3DecodeContext *ctx)
static void do_rematrixing(AC3DecodeContext *s)
{
int bnd, i;
int end, bndend;
float tmp0, tmp1;
end = FFMIN(ctx->end_freq[1], ctx->end_freq[2]);
end = FFMIN(s->end_freq[1], s->end_freq[2]);
for(bnd=0; bnd<ctx->num_rematrixing_bands; bnd++) {
if(ctx->rematrixing_flags[bnd]) {
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 = ctx->transform_coeffs[1][i];
tmp1 = ctx->transform_coeffs[2][i];
ctx->transform_coeffs[1][i] = tmp0 + tmp1;
ctx->transform_coeffs[2][i] = tmp0 - tmp1;
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;
}
}
}
@ -661,21 +661,21 @@ static void do_rematrixing(AC3DecodeContext *ctx)
/**
* Perform the 256-point IMDCT
*/
static void do_imdct_256(AC3DecodeContext *ctx, int chindex)
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 = ctx->tmp_output;
float *o_ptr = s->tmp_output;
for(i=0; i<2; i++) {
/* de-interleave coefficients */
for(k=0; k<128; k++) {
x[k] = ctx->transform_coeffs[chindex][2*k+i];
x[k] = s->transform_coeffs[chindex][2*k+i];
}
/* run standard IMDCT */
ctx->imdct_256.fft.imdct_calc(&ctx->imdct_256, o_ptr, x, ctx->tmp_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++) {
@ -704,32 +704,32 @@ static void do_imdct_256(AC3DecodeContext *ctx, int chindex)
* Convert frequency domain coefficients to time-domain audio samples.
* reference: Section 7.9.4 Transformation Equations
*/
static inline void do_imdct(AC3DecodeContext *ctx)
static inline void do_imdct(AC3DecodeContext *s)
{
int ch;
int channels;
/* Don't perform the IMDCT on the LFE channel unless it's used in the output */
channels = ctx->fbw_channels;
if(ctx->output_mode & AC3_OUTPUT_LFEON)
channels = s->fbw_channels;
if(s->output_mode & AC3_OUTPUT_LFEON)
channels++;
for (ch=1; ch<=channels; ch++) {
if (ctx->block_switch[ch]) {
do_imdct_256(ctx, ch);
if (s->block_switch[ch]) {
do_imdct_256(s, ch);
} else {
ctx->imdct_512.fft.imdct_calc(&ctx->imdct_512, ctx->tmp_output,
ctx->transform_coeffs[ch],
ctx->tmp_imdct);
s->imdct_512.fft.imdct_calc(&s->imdct_512, s->tmp_output,
s->transform_coeffs[ch],
s->tmp_imdct);
}
/* For the first half of the block, apply the window, add the delay
from the previous block, and send to output */
ctx->dsp.vector_fmul_add_add(ctx->output[ch-1], ctx->tmp_output,
ctx->window, ctx->delay[ch-1], 0, 256, 1);
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 */
ctx->dsp.vector_fmul_reverse(ctx->delay[ch-1], ctx->tmp_output+256,
ctx->window, 256);
s->dsp.vector_fmul_reverse(s->delay[ch-1], s->tmp_output+256,
s->window, 256);
}
}
@ -764,182 +764,182 @@ static void ac3_downmix(float samples[AC3_MAX_CHANNELS][256], int fbw_channels,
/**
* Parse an audio block from AC-3 bitstream.
*/
static int ac3_parse_audio_block(AC3DecodeContext *ctx, int blk)
static int ac3_parse_audio_block(AC3DecodeContext *s, int blk)
{
int fbw_channels = ctx->fbw_channels;
int channel_mode = ctx->channel_mode;
int fbw_channels = s->fbw_channels;
int channel_mode = s->channel_mode;
int i, bnd, seg, ch;
GetBitContext *gbc = &ctx->gbc;
GetBitContext *gbc = &s->gbc;
uint8_t bit_alloc_stages[AC3_MAX_CHANNELS];
memset(bit_alloc_stages, 0, AC3_MAX_CHANNELS);
/* block switch flags */
for (ch = 1; ch <= fbw_channels; ch++)
ctx->block_switch[ch] = get_bits1(gbc);
s->block_switch[ch] = get_bits1(gbc);
/* dithering flags */
ctx->dither_all = 1;
s->dither_all = 1;
for (ch = 1; ch <= fbw_channels; ch++) {
ctx->dither_flag[ch] = get_bits1(gbc);
if(!ctx->dither_flag[ch])
ctx->dither_all = 0;
s->dither_flag[ch] = get_bits1(gbc);
if(!s->dither_flag[ch])
s->dither_all = 0;
}
/* dynamic range */
i = !(ctx->channel_mode);
i = !(s->channel_mode);
do {
if(get_bits1(gbc)) {
ctx->dynamic_range[i] = ((dynamic_range_tab[get_bits(gbc, 8)]-1.0) *
ctx->avctx->drc_scale)+1.0;
s->dynamic_range[i] = ((dynamic_range_tab[get_bits(gbc, 8)]-1.0) *
s->avctx->drc_scale)+1.0;
} else if(blk == 0) {
ctx->dynamic_range[i] = 1.0f;
s->dynamic_range[i] = 1.0f;
}
} while(i--);
/* coupling strategy */
if (get_bits1(gbc)) {
memset(bit_alloc_stages, 3, AC3_MAX_CHANNELS);
ctx->cpl_in_use = get_bits1(gbc);
if (ctx->cpl_in_use) {
s->cpl_in_use = get_bits1(gbc);
if (s->cpl_in_use) {
/* coupling in use */
int cpl_begin_freq, cpl_end_freq;
/* determine which channels are coupled */
for (ch = 1; ch <= fbw_channels; ch++)
ctx->channel_in_cpl[ch] = get_bits1(gbc);
s->channel_in_cpl[ch] = get_bits1(gbc);
/* phase flags in use */
if (channel_mode == AC3_CHMODE_STEREO)
ctx->phase_flags_in_use = get_bits1(gbc);
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(ctx->avctx, AV_LOG_ERROR, "3+cplendf = %d < cplbegf = %d\n", 3+cpl_end_freq, cpl_begin_freq);
av_log(s->avctx, AV_LOG_ERROR, "3+cplendf = %d < cplbegf = %d\n", 3+cpl_end_freq, cpl_begin_freq);
return -1;
}
ctx->num_cpl_bands = ctx->num_cpl_subbands = 3 + cpl_end_freq - cpl_begin_freq;
ctx->start_freq[CPL_CH] = cpl_begin_freq * 12 + 37;
ctx->end_freq[CPL_CH] = cpl_end_freq * 12 + 73;
for (bnd = 0; bnd < ctx->num_cpl_subbands - 1; bnd++) {
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)) {
ctx->cpl_band_struct[bnd] = 1;
ctx->num_cpl_bands--;
s->cpl_band_struct[bnd] = 1;
s->num_cpl_bands--;
}
}
} else {
/* coupling not in use */
for (ch = 1; ch <= fbw_channels; ch++)
ctx->channel_in_cpl[ch] = 0;
s->channel_in_cpl[ch] = 0;
}
}
/* coupling coordinates */
if (ctx->cpl_in_use) {
if (s->cpl_in_use) {
int cpl_coords_exist = 0;
for (ch = 1; ch <= fbw_channels; ch++) {
if (ctx->channel_in_cpl[ch]) {
if (s->channel_in_cpl[ch]) {
if (get_bits1(gbc)) {
int master_cpl_coord, cpl_coord_exp, cpl_coord_mant;
cpl_coords_exist = 1;
master_cpl_coord = 3 * get_bits(gbc, 2);
for (bnd = 0; bnd < ctx->num_cpl_bands; bnd++) {
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)
ctx->cpl_coords[ch][bnd] = cpl_coord_mant / 16.0f;
s->cpl_coords[ch][bnd] = cpl_coord_mant / 16.0f;
else
ctx->cpl_coords[ch][bnd] = (cpl_coord_mant + 16.0f) / 32.0f;
ctx->cpl_coords[ch][bnd] *= scale_factors[cpl_coord_exp + master_cpl_coord];
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];
}
}
}
}
/* phase flags */
if (channel_mode == AC3_CHMODE_STEREO && ctx->phase_flags_in_use && cpl_coords_exist) {
for (bnd = 0; bnd < ctx->num_cpl_bands; bnd++) {
if (channel_mode == AC3_CHMODE_STEREO && s->phase_flags_in_use && cpl_coords_exist) {
for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
if (get_bits1(gbc))
ctx->cpl_coords[2][bnd] = -ctx->cpl_coords[2][bnd];
s->cpl_coords[2][bnd] = -s->cpl_coords[2][bnd];
}
}
}
/* stereo rematrixing strategy and band structure */
if (channel_mode == AC3_CHMODE_STEREO) {
ctx->rematrixing_strategy = get_bits1(gbc);
if (ctx->rematrixing_strategy) {
ctx->num_rematrixing_bands = 4;
if(ctx->cpl_in_use && ctx->start_freq[CPL_CH] <= 61)
ctx->num_rematrixing_bands -= 1 + (ctx->start_freq[CPL_CH] == 37);
for(bnd=0; bnd<ctx->num_rematrixing_bands; bnd++)
ctx->rematrixing_flags[bnd] = get_bits1(gbc);
s->rematrixing_strategy = get_bits1(gbc);
if (s->rematrixing_strategy) {
s->num_rematrixing_bands = 4;
if(s->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++)
s->rematrixing_flags[bnd] = get_bits1(gbc);
}
}
/* exponent strategies for each channel */
ctx->exp_strategy[CPL_CH] = EXP_REUSE;
ctx->exp_strategy[ctx->lfe_ch] = EXP_REUSE;
for (ch = !ctx->cpl_in_use; ch <= ctx->channels; ch++) {
if(ch == ctx->lfe_ch)
ctx->exp_strategy[ch] = get_bits(gbc, 1);
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
ctx->exp_strategy[ch] = get_bits(gbc, 2);
if(ctx->exp_strategy[ch] != EXP_REUSE)
s->exp_strategy[ch] = get_bits(gbc, 2);
if(s->exp_strategy[ch] != EXP_REUSE)
bit_alloc_stages[ch] = 3;
}
/* channel bandwidth */
for (ch = 1; ch <= fbw_channels; ch++) {
ctx->start_freq[ch] = 0;
if (ctx->exp_strategy[ch] != EXP_REUSE) {
int prev = ctx->end_freq[ch];
if (ctx->channel_in_cpl[ch])
ctx->end_freq[ch] = ctx->start_freq[CPL_CH];
s->start_freq[ch] = 0;
if (s->exp_strategy[ch] != EXP_REUSE) {
int prev = s->end_freq[ch];
if (s->channel_in_cpl[ch])
s->end_freq[ch] = s->start_freq[CPL_CH];
else {
int bandwidth_code = get_bits(gbc, 6);
if (bandwidth_code > 60) {
av_log(ctx->avctx, AV_LOG_ERROR, "bandwidth code = %d > 60", bandwidth_code);
av_log(s->avctx, AV_LOG_ERROR, "bandwidth code = %d > 60", bandwidth_code);
return -1;
}
ctx->end_freq[ch] = bandwidth_code * 3 + 73;
s->end_freq[ch] = bandwidth_code * 3 + 73;
}
if(blk > 0 && ctx->end_freq[ch] != prev)
if(blk > 0 && s->end_freq[ch] != prev)
memset(bit_alloc_stages, 3, AC3_MAX_CHANNELS);
}
}
ctx->start_freq[ctx->lfe_ch] = 0;
ctx->end_freq[ctx->lfe_ch] = 7;
s->start_freq[s->lfe_ch] = 0;
s->end_freq[s->lfe_ch] = 7;
/* decode exponents for each channel */
for (ch = !ctx->cpl_in_use; ch <= ctx->channels; ch++) {
if (ctx->exp_strategy[ch] != EXP_REUSE) {
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 << (ctx->exp_strategy[ch] - 1);
group_size = 3 << (s->exp_strategy[ch] - 1);
if(ch == CPL_CH)
num_groups = (ctx->end_freq[ch] - ctx->start_freq[ch]) / group_size;
else if(ch == ctx->lfe_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 = (ctx->end_freq[ch] + group_size - 4) / group_size;
ctx->dexps[ch][0] = get_bits(gbc, 4) << !ch;
decode_exponents(gbc, ctx->exp_strategy[ch], num_groups, ctx->dexps[ch][0],
&ctx->dexps[ch][ctx->start_freq[ch]+!!ch]);
if(ch != CPL_CH && ch != ctx->lfe_ch)
num_groups = (s->end_freq[ch] + group_size - 4) / group_size;
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)
skip_bits(gbc, 2); /* skip gainrng */
}
}
/* bit allocation information */
if (get_bits1(gbc)) {
ctx->bit_alloc_params.slow_decay = ff_ac3_slow_decay_tab[get_bits(gbc, 2)] >> ctx->bit_alloc_params.sr_shift;
ctx->bit_alloc_params.fast_decay = ff_ac3_fast_decay_tab[get_bits(gbc, 2)] >> ctx->bit_alloc_params.sr_shift;
ctx->bit_alloc_params.slow_gain = ff_ac3_slow_gain_tab[get_bits(gbc, 2)];
ctx->bit_alloc_params.db_per_bit = ff_ac3_db_per_bit_tab[get_bits(gbc, 2)];
ctx->bit_alloc_params.floor = ff_ac3_floor_tab[get_bits(gbc, 3)];
for(ch=!ctx->cpl_in_use; ch<=ctx->channels; ch++) {
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);
}
}
@ -948,73 +948,73 @@ static int ac3_parse_audio_block(AC3DecodeContext *ctx, int blk)
if (get_bits1(gbc)) {
int csnr;
csnr = (get_bits(gbc, 6) - 15) << 4;
for (ch = !ctx->cpl_in_use; ch <= ctx->channels; ch++) { /* snr offset and fast gain */
ctx->snr_offset[ch] = (csnr + get_bits(gbc, 4)) << 2;
ctx->fast_gain[ch] = ff_ac3_fast_gain_tab[get_bits(gbc, 3)];
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;
s->fast_gain[ch] = ff_ac3_fast_gain_tab[get_bits(gbc, 3)];
}
memset(bit_alloc_stages, 3, AC3_MAX_CHANNELS);
}
/* coupling leak information */
if (ctx->cpl_in_use && get_bits1(gbc)) {
ctx->bit_alloc_params.cpl_fast_leak = get_bits(gbc, 3);
ctx->bit_alloc_params.cpl_slow_leak = get_bits(gbc, 3);
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);
}
/* delta bit allocation information */
if (get_bits1(gbc)) {
/* delta bit allocation exists (strategy) */
for (ch = !ctx->cpl_in_use; ch <= fbw_channels; ch++) {
ctx->dba_mode[ch] = get_bits(gbc, 2);
if (ctx->dba_mode[ch] == DBA_RESERVED) {
av_log(ctx->avctx, AV_LOG_ERROR, "delta bit allocation strategy reserved\n");
for (ch = !s->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");
return -1;
}
bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2);
}
/* channel delta offset, len and bit allocation */
for (ch = !ctx->cpl_in_use; ch <= fbw_channels; ch++) {
if (ctx->dba_mode[ch] == DBA_NEW) {
ctx->dba_nsegs[ch] = get_bits(gbc, 3);
for (seg = 0; seg <= ctx->dba_nsegs[ch]; seg++) {
ctx->dba_offsets[ch][seg] = get_bits(gbc, 5);
ctx->dba_lengths[ch][seg] = get_bits(gbc, 4);
ctx->dba_values[ch][seg] = get_bits(gbc, 3);
for (ch = !s->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_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);
}
}
}
} else if(blk == 0) {
for(ch=0; ch<=ctx->channels; ch++) {
ctx->dba_mode[ch] = DBA_NONE;
for(ch=0; ch<=s->channels; ch++) {
s->dba_mode[ch] = DBA_NONE;
}
}
/* Bit allocation */
for(ch=!ctx->cpl_in_use; ch<=ctx->channels; ch++) {
for(ch=!s->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(ctx->dexps[ch],
ctx->start_freq[ch], ctx->end_freq[ch],
ctx->psd[ch], ctx->band_psd[ch]);
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) {
/* Compute excitation function, Compute masking curve, and
Apply delta bit allocation */
ff_ac3_bit_alloc_calc_mask(&ctx->bit_alloc_params, ctx->band_psd[ch],
ctx->start_freq[ch], ctx->end_freq[ch],
ctx->fast_gain[ch], (ch == ctx->lfe_ch),
ctx->dba_mode[ch], ctx->dba_nsegs[ch],
ctx->dba_offsets[ch], ctx->dba_lengths[ch],
ctx->dba_values[ch], ctx->mask[ch]);
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(bit_alloc_stages[ch] > 0) {
/* Compute bit allocation */
ff_ac3_bit_alloc_calc_bap(ctx->mask[ch], ctx->psd[ch],
ctx->start_freq[ch], ctx->end_freq[ch],
ctx->snr_offset[ch],
ctx->bit_alloc_params.floor,
ctx->bap[ch]);
ff_ac3_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]);
}
}
@ -1027,43 +1027,43 @@ static int ac3_parse_audio_block(AC3DecodeContext *ctx, int blk)
/* unpack the transform coefficients
this also uncouples channels if coupling is in use. */
if (get_transform_coeffs(ctx)) {
av_log(ctx->avctx, AV_LOG_ERROR, "Error in routine get_transform_coeffs\n");
if (get_transform_coeffs(s)) {
av_log(s->avctx, AV_LOG_ERROR, "Error in routine get_transform_coeffs\n");
return -1;
}
/* recover coefficients if rematrixing is in use */
if(ctx->channel_mode == AC3_CHMODE_STEREO)
do_rematrixing(ctx);
if(s->channel_mode == AC3_CHMODE_STEREO)
do_rematrixing(s);
/* apply scaling to coefficients (headroom, dynrng) */
for(ch=1; ch<=ctx->channels; ch++) {
float gain = 2.0f * ctx->mul_bias;
if(ctx->channel_mode == AC3_CHMODE_DUALMONO) {
gain *= ctx->dynamic_range[ch-1];
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];
} else {
gain *= ctx->dynamic_range[0];
gain *= s->dynamic_range[0];
}
for(i=0; i<ctx->end_freq[ch]; i++) {
ctx->transform_coeffs[ch][i] *= gain;
for(i=0; i<s->end_freq[ch]; i++) {
s->transform_coeffs[ch][i] *= gain;
}
}
do_imdct(ctx);
do_imdct(s);
/* downmix output if needed */
if(ctx->channels != ctx->out_channels && !((ctx->output_mode & AC3_OUTPUT_LFEON) &&
ctx->fbw_channels == ctx->out_channels)) {
ac3_downmix(ctx->output, ctx->fbw_channels, ctx->output_mode,
ctx->downmix_coeffs);
if(s->channels != s->out_channels && !((s->output_mode & AC3_OUTPUT_LFEON) &&
s->fbw_channels == s->out_channels)) {
ac3_downmix(s->output, s->fbw_channels, s->output_mode,
s->downmix_coeffs);
}
/* convert float to 16-bit integer */
for(ch=0; ch<ctx->out_channels; ch++) {
for(ch=0; ch<s->out_channels; ch++) {
for(i=0; i<256; i++) {
ctx->output[ch][i] += ctx->add_bias;
s->output[ch][i] += s->add_bias;
}
ctx->dsp.float_to_int16(ctx->int_output[ch], ctx->output[ch], 256);
s->dsp.float_to_int16(s->int_output[ch], s->output[ch], 256);
}
return 0;
@ -1074,15 +1074,15 @@ static int ac3_parse_audio_block(AC3DecodeContext *ctx, int blk)
*/
static int ac3_decode_frame(AVCodecContext * avctx, void *data, int *data_size, uint8_t *buf, int buf_size)
{
AC3DecodeContext *ctx = (AC3DecodeContext *)avctx->priv_data;
AC3DecodeContext *s = (AC3DecodeContext *)avctx->priv_data;
int16_t *out_samples = (int16_t *)data;
int i, blk, ch, err;
/* initialize the GetBitContext with the start of valid AC-3 Frame */
init_get_bits(&ctx->gbc, buf, buf_size * 8);
init_get_bits(&s->gbc, buf, buf_size * 8);
/* parse the syncinfo */
err = ac3_parse_header(ctx);
err = ac3_parse_header(s);
if(err) {
switch(err) {
case AC3_PARSE_ERROR_SYNC:
@ -1104,37 +1104,37 @@ static int ac3_decode_frame(AVCodecContext * avctx, void *data, int *data_size,
return -1;
}
avctx->sample_rate = ctx->sampling_rate;
avctx->bit_rate = ctx->bit_rate;
avctx->sample_rate = s->sampling_rate;
avctx->bit_rate = s->bit_rate;
/* check that reported frame size fits in input buffer */
if(ctx->frame_size > buf_size) {
if(s->frame_size > buf_size) {
av_log(avctx, AV_LOG_ERROR, "incomplete frame\n");
return -1;
}
/* channel config */
ctx->out_channels = ctx->channels;
s->out_channels = s->channels;
if (avctx->request_channels > 0 && avctx->request_channels <= 2 &&
avctx->request_channels < ctx->channels) {
ctx->out_channels = avctx->request_channels;
ctx->output_mode = avctx->request_channels == 1 ? AC3_CHMODE_MONO : AC3_CHMODE_STEREO;
avctx->request_channels < s->channels) {
s->out_channels = avctx->request_channels;
s->output_mode = avctx->request_channels == 1 ? AC3_CHMODE_MONO : AC3_CHMODE_STEREO;
}
avctx->channels = ctx->out_channels;
avctx->channels = s->out_channels;
/* parse the audio blocks */
for (blk = 0; blk < NB_BLOCKS; blk++) {
if (ac3_parse_audio_block(ctx, blk)) {
if (ac3_parse_audio_block(s, blk)) {
av_log(avctx, AV_LOG_ERROR, "error parsing the audio block\n");
*data_size = 0;
return ctx->frame_size;
return s->frame_size;
}
for (i = 0; i < 256; i++)
for (ch = 0; ch < ctx->out_channels; ch++)
*(out_samples++) = ctx->int_output[ch][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 ctx->frame_size;
return s->frame_size;
}
/**
@ -1142,9 +1142,9 @@ static int ac3_decode_frame(AVCodecContext * avctx, void *data, int *data_size,
*/
static int ac3_decode_end(AVCodecContext *avctx)
{
AC3DecodeContext *ctx = (AC3DecodeContext *)avctx->priv_data;
ff_mdct_end(&ctx->imdct_512);
ff_mdct_end(&ctx->imdct_256);
AC3DecodeContext *s = (AC3DecodeContext *)avctx->priv_data;
ff_mdct_end(&s->imdct_512);
ff_mdct_end(&s->imdct_256);
return 0;
}

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