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Implement revert_mclms() and associated functions

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This commit is contained in:
Mashiat Sarker Shakkhar 2011-11-30 22:41:12 +06:00
parent bf8715719a
commit 8aa831c07b
1 changed files with 87 additions and 0 deletions
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87
libavcodec/wmalosslessdec.c
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@ -786,6 +786,93 @@ static void reset_codec(WmallDecodeCtx *s)
static void mclms_update(WmallDecodeCtx *s, int icoef)
{
int i, j, ich;
int16_t pred_error;
int order = s->mclms_order;
int num_channels = s->num_channels;
int16_t range = 1 << (s->bits_per_sample - 1);
int bps = s->bits_per_sample > 16 ? 4 : 2; // bytes per sample
for (ich = 0; ich < num_channels; ich++) {
pred_error = s->channel_coeffs[ich][icoef] -
s->channel_residues[ich][icoef];
if (pred_error > 0) {
for (i = 0; i < order * num_channels; i++)
s->mclms_coeffs[i + ich * order * num_channels] +=
s->mclms_updates[s->mclms_recent + i];
for (j = 0; j < i; j++) {
if (s->channel_coeffs[ich][icoef] > 0)
s->mclms_coeffs_cur[ich * num_channels + j] += 1;
else if (s->channel_coeffs[ich][icoef] < 0)
s->mclms_coeffs_cur[ich * num_channels + j] -= 1;
}
} else if (pred_error < 0) {
for (i = 0; i < order * num_channels; i++)
s->mclms_coeffs[i + ich * order * num_channels] -=
s->mclms_updates[s->mclms_recent + i];
for (j = 0; j < i; j++) {
if (s->channel_coeffs[ich][icoef] > 0)
s->mclms_coeffs_cur[ich * num_channels + j] -= 1;
else if (s->channel_coeffs[ich][icoef] < 0)
s->mclms_coeffs_cur[ich * num_channels + j] += 1;
}
}
}
for (ich = num_channels - 1; ich >= 0; ich--) {
s->mclms_recent--;
if (s->channel_coeffs[ich][icoef] > range - 1)
s->mclms_prevvalues[s->mclms_recent] = range - 1;
else if (s->channel_coeffs[ich][icoef] <= -range)
s->mclms_prevvalues[s->mclms_recent] = -range;
s->mclms_updates[s->mclms_recent] =
av_clip(-1, s->channel_coeffs[ich][icoef], 1);
}
if (s->mclms_recent == 0) {
memcpy(s->mclms_prevvalues[order * num_channels],
s->mclms_prevvalues,
bps * order * num_channels);
memcpy(s->mclms_updates[order * num_channels],
s->mclms_updates,
bps * order * num_channels);
s->mclms_recent = num_channels * order;
}
}
static void mclms_predict(WmallDecodeCtx *s, int icoef)
{
int ich, i;
int16_t pred;
int order = s->mclms_order;
int num_channels = s->num_channels;
for (ich = 0; ich < num_channels; ich++) {
if (!s->is_channel_coded[ich])
continue;
pred = 0;
for (i = 0; i < order * num_channels; i++)
pred += s->mclms_prevvalues[i] *
s->mclms_coeffs[i + order * num_channels * ich];
for (i = 0; i < ich; i++)
pred += s->channel_coeffs[ich][icoef] *
s->mclms_coeffs_cur[i + order * num_channels * ich];
s->channel_coeffs[ich][icoef] =
s->channel_residues[ich][icoef] + pred;
}
}
static void revert_mclms(WmallDecodeCtx *s, int tile_size)
{
int icoef;
for (icoef = 0; icoef < tile_size; icoef++) {
mclms_predict(s, icoef);
mclms_update(s, icoef);
}
}
static int lms_predict(WmallDecodeCtx *s, int ich, int ilms)
{
int16_t pred = 0, icoef;