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alacenc: increase predictor buffer

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This change is almost cosmetical only, and reduces the changes needed to
fix the 24bps case.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Christophe Gisquet 2014-08-17 17:09:13 +00:00 • committed by Michael Niedermayer
parent 882fb53cb7
commit c0d18cc085
1 changed files with 10 additions and 9 deletions
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19
libavcodec/alacenc.c
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@ -66,7 +66,7 @@ typedef struct AlacEncodeContext {
int write_sample_size;
int extra_bits;
int32_t sample_buf[2][DEFAULT_FRAME_SIZE];
int32_t predictor_buf[DEFAULT_FRAME_SIZE];
int32_t predictor_buf[2][DEFAULT_FRAME_SIZE];
int interlacing_shift;
int interlacing_leftweight;
PutBitContext pbctx;
@ -253,13 +253,14 @@ static void alac_linear_predictor(AlacEncodeContext *s, int ch)
{
int i;
AlacLPCContext lpc = s->lpc[ch];
int32_t *residual = s->predictor_buf[ch];
if (lpc.lpc_order == 31) {
s->predictor_buf[0] = s->sample_buf[ch][0];
residual[0] = s->sample_buf[ch][0];
for (i = 1; i < s->frame_size; i++) {
s->predictor_buf[i] = s->sample_buf[ch][i ] -
s->sample_buf[ch][i - 1];
residual[i] = s->sample_buf[ch][i ] -
s->sample_buf[ch][i - 1];
}
return;
@ -269,7 +270,6 @@ static void alac_linear_predictor(AlacEncodeContext *s, int ch)
if (lpc.lpc_order > 0) {
int32_t *samples = s->sample_buf[ch];
int32_t *residual = s->predictor_buf;
// generate warm-up samples
residual[0] = samples[0];
@ -313,11 +313,11 @@ static void alac_linear_predictor(AlacEncodeContext *s, int ch)
}
}
static void alac_entropy_coder(AlacEncodeContext *s)
static void alac_entropy_coder(AlacEncodeContext *s, int ch)
{
unsigned int history = s->rc.initial_history;
int sign_modifier = 0, i, k;
int32_t *samples = s->predictor_buf;
int32_t *samples = s->predictor_buf[ch];
for (i = 0; i < s->frame_size;) {
int x;
@ -432,10 +432,11 @@ static void write_element(AlacEncodeContext *s,
// TODO: determine when this will actually help. for now it's not used.
if (prediction_type == 15) {
// 2nd pass 1st order filter
int32_t *residual = s->predictor_buf[channels];
for (j = s->frame_size - 1; j > 0; j--)
s->predictor_buf[j] -= s->predictor_buf[j - 1];
residual[j] -= residual[j - 1];
}
alac_entropy_coder(s);
alac_entropy_coder(s, i);
}
}
}