#include <stdint.h>
-#include "ac3enc.h"
-
/* prototypes for static functions in ac3enc_fixed.c and ac3enc_float.c */
static int normalize_samples(AC3EncodeContext *s);
+static void clip_coefficients(DSPContext *dsp, CoefType *coef, unsigned int len);
+
+static CoefType calc_cpl_coord(CoefSumType energy_ch, CoefSumType energy_cpl);
+
+static void sum_square_butterfly(AC3EncodeContext *s, CoefSumType sum[4],
+ const CoefType *coef0, const CoefType *coef1,
+ int len);
int AC3_NAME(allocate_sample_buffers)(AC3EncodeContext *s)
{
}
-/**
+/*
* Deinterleave input samples.
- * Channels are reordered from Libav's default order to AC-3 order.
+ * Channels are reordered from FFmpeg's default order to AC-3 order.
*/
static void deinterleave_input_samples(AC3EncodeContext *s,
const SampleType *samples)
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],
+ memcpy(&s->planar_samples[ch][0], &s->planar_samples[ch][AC3_BLOCK_SIZE * s->num_blocks],
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++) {
+ for (i = AC3_BLOCK_SIZE; i < AC3_BLOCK_SIZE * (s->num_blocks + 1); 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.
int blk, ch;
for (ch = 0; ch < s->channels; ch++) {
- for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
+ for (blk = 0; blk < s->num_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);
+ s->mdct_window, AC3_WINDOW_SIZE);
if (s->fixed_point)
block->coeff_shift[ch+1] = normalize_samples(s);
- s->mdct->fft.mdct_calcw(&s->mdct->fft, block->mdct_coef[ch+1],
- s->windowed_samples);
+ s->mdct.mdct_calcw(&s->mdct, block->mdct_coef[ch+1],
+ s->windowed_samples);
}
}
}
-/**
- * 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)
{
+ LOCAL_ALIGNED_16(CoefType, cpl_coords, [AC3_MAX_BLOCKS], [AC3_MAX_CHANNELS][16]);
#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]);
+#else
+ int32_t (*fixed_cpl_coords)[AC3_MAX_CHANNELS][16] = cpl_coords;
+#endif
int blk, ch, bnd, i, j;
CoefSumType energy[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][16] = {{{0}}};
int cpl_start, num_cpl_coefs;
memset(cpl_coords, 0, AC3_MAX_BLOCKS * sizeof(*cpl_coords));
- memset(fixed_cpl_coords, 0, AC3_MAX_BLOCKS * sizeof(*fixed_cpl_coords));
+#if CONFIG_AC3ENC_FLOAT
+ memset(fixed_cpl_coords, 0, AC3_MAX_BLOCKS * sizeof(*cpl_coords));
+#endif
/* align start to 16-byte boundary. align length to multiple of 32.
note: coupling start bin % 4 will always be 1 */
cpl_start = FFMIN(256, cpl_start + num_cpl_coefs) - num_cpl_coefs;
/* calculate coupling channel from fbw channels */
- for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
+ for (blk = 0; blk < s->num_blocks; blk++) {
AC3Block *block = &s->blocks[blk];
CoefType *cpl_coef = &block->mdct_coef[CPL_CH][cpl_start];
if (!block->cpl_in_use)
cpl_coef[i] += ch_coef[i];
}
- /* coefficients must be clipped to +/- 1.0 in order to be encoded */
- s->dsp.vector_clipf(cpl_coef, cpl_coef, -1.0f, 1.0f, num_cpl_coefs);
-
- /* scale coupling coefficients from float to 24-bit fixed-point */
- s->ac3dsp.float_to_fixed24(&block->fixed_coef[CPL_CH][cpl_start],
- cpl_coef, num_cpl_coefs);
+ /* coefficients must be clipped in order to be encoded */
+ clip_coefficients(&s->dsp, cpl_coef, num_cpl_coefs);
}
/* calculate energy in each band in coupling channel and each fbw channel */
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++) {
+ for (blk = 0; blk < s->num_blocks; blk++) {
AC3Block *block = &s->blocks[blk];
if (!block->cpl_in_use || (ch > CPL_CH && !block->channel_in_cpl[ch]))
continue;
bnd++;
}
+ /* calculate coupling coordinates for all blocks for all channels */
+ for (blk = 0; blk < s->num_blocks; blk++) {
+ AC3Block *block = &s->blocks[blk];
+ if (!block->cpl_in_use)
+ continue;
+ 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]);
+ }
+ }
+ }
+
/* determine which blocks to send new coupling coordinates for */
- for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
+ for (blk = 0; blk < s->num_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;
- }
+ memset(block->new_cpl_coords, 0, sizeof(block->new_cpl_coords));
+ if (block->cpl_in_use) {
/* 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;
+ if (blk == 0 || !block0->cpl_in_use) {
+ for (ch = 1; ch <= s->fbw_channels; ch++)
+ block->new_cpl_coords[ch] = 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;
+ if (!block->channel_in_cpl[ch])
+ continue;
+ if (!block0->channel_in_cpl[ch]) {
+ block->new_cpl_coords[ch] = 1;
+ } else {
+ CoefSumType coord_diff = 0;
+ for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
+ coord_diff += FFABS(cpl_coords[blk-1][ch][bnd] -
+ cpl_coords[blk ][ch][bnd]);
}
+ coord_diff /= s->num_cpl_bands;
+ if (coord_diff > NEW_CPL_COORD_THRESHOLD)
+ block->new_cpl_coords[ch] = 1;
}
}
}
}
- 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;
+ while (blk < s->num_blocks) {
+ int av_uninit(blk1);
AC3Block *block = &s->blocks[blk];
if (!block->cpl_in_use) {
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;
+ CoefSumType energy_ch, energy_cpl;
if (!block->channel_in_cpl[ch])
continue;
+ energy_cpl = energy[blk][CPL_CH][bnd];
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)
+ while (!s->blocks[blk1].new_cpl_coords[ch] && blk1 < s->num_blocks) {
+ if (s->blocks[blk1].cpl_in_use) {
+ energy_cpl += energy[blk1][CPL_CH][bnd];
energy_ch += energy[blk1][ch][bnd];
+ }
blk1++;
}
cpl_coords[blk][ch][bnd] = calc_cpl_coord(energy_ch, energy_cpl);
}
/* calculate exponents/mantissas for coupling coordinates */
- for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
+ for (blk = 0; blk < s->num_blocks; blk++) {
AC3Block *block = &s->blocks[blk];
- if (!block->cpl_in_use || !block->new_cpl_coords)
+ if (!block->cpl_in_use)
continue;
+#if CONFIG_AC3ENC_FLOAT
s->ac3dsp.float_to_fixed24(fixed_cpl_coords[blk][1],
cpl_coords[blk][1],
s->fbw_channels * 16);
+#endif
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;
+ if (!block->new_cpl_coords[ch])
+ continue;
+
/* determine master exponent */
min_exp = max_exp = block->cpl_coord_exp[ch][0];
for (bnd = 1; bnd < s->num_cpl_bands; bnd++) {
if (CONFIG_EAC3_ENCODER && s->eac3)
ff_eac3_set_cpl_states(s);
-#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;
+ int blk, bnd;
AC3Block *block, *av_uninit(block0);
if (s->channel_mode != AC3_CHMODE_STEREO)
return;
- for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
+ for (blk = 0; blk < s->num_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);
}
nb_coefs = FFMIN(block->end_freq[1], block->end_freq[2]);
+ if (!s->rematrixing_enabled) {
+ block0 = block;
+ continue;
+ }
+
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);
- }
+ CoefSumType sum[4];
+ sum_square_butterfly(s, sum, block->mdct_coef[1] + start,
+ block->mdct_coef[2] + start, end - start);
/* compare sums to determine if rematrixing will be used for this band */
if (FFMIN(sum[2], sum[3]) < FFMIN(sum[0], sum[1]))
}
-/**
- * Encode a single AC-3 frame.
- */
int AC3_NAME(encode_frame)(AVCodecContext *avctx, unsigned char *frame,
int buf_size, void *data)
{
const SampleType *samples = data;
int ret;
- if (!s->eac3 && s->options.allow_per_frame_metadata) {
- ret = ff_ac3_validate_metadata(avctx);
+ if (s->options.allow_per_frame_metadata) {
+ ret = ff_ac3_validate_metadata(s);
if (ret)
return ret;
}
apply_mdct(s);
- scale_coefficients(s);
+ if (s->fixed_point)
+ scale_coefficients(s);
+
+ clip_coefficients(&s->dsp, s->blocks[0].mdct_coef[1],
+ AC3_MAX_COEFS * s->num_blocks * s->channels);
s->cpl_on = s->cpl_enabled;
ff_ac3_compute_coupling_strategy(s);
compute_rematrixing_strategy(s);
+ if (!s->fixed_point)
+ scale_coefficients(s);
+
ff_ac3_apply_rematrixing(s);
ff_ac3_process_exponents(s);
return ret;
}
+ ff_ac3_group_exponents(s);
+
ff_ac3_quantize_mantissas(s);
ff_ac3_output_frame(s, frame);