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use block-based allocation for backward refs storage, and free-lists

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Non-photo source produce far less literal reference and their
buffer is usually much smaller than the picture size if its compresses
well. Hence, use a block-base allocation (and recycling) to avoid
pre-allocating a buffer with maximal size.

This can reduce memory consumption up to 50% for non-photographic
content. Encode speed is also a little better (1-2%)

Change-Id: Icbc229e1e5a08976348e600c8906beaa26954a11
This commit is contained in:
skal
2014-05-05 11:11:55 -07:00
parent 1ba61b09f9
commit ca3d746e39
5 changed files with 225 additions and 124 deletions
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14
src/enc/histogram.c
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@ -64,9 +64,10 @@ void VP8LFreeHistogramSet(VP8LHistogramSet* const histo) {
void VP8LHistogramStoreRefs(const VP8LBackwardRefs* const refs,
VP8LHistogram* const histo) {
int i;
for (i = 0; i < refs->size; ++i) {
VP8LHistogramAddSinglePixOrCopy(histo, &refs->refs[i]);
VP8LRefsCursor c = VP8LRefsCursorInit(refs);
while (VP8LRefsCursorOk(&c)) {
VP8LHistogramAddSinglePixOrCopy(histo, c.cur_pos);
VP8LRefsCursorNext(&c);
}
}
@ -423,14 +424,14 @@ static int GetHistoBinIndex(
static void HistogramBuild(
int xsize, int histo_bits, const VP8LBackwardRefs* const backward_refs,
VP8LHistogramSet* const init_histo) {
int i;
int x = 0, y = 0;
const int histo_xsize = VP8LSubSampleSize(xsize, histo_bits);
VP8LHistogram** const histograms = init_histo->histograms;
VP8LRefsCursor c = VP8LRefsCursorInit(backward_refs);
assert(histo_bits > 0);
// Construct the Histo from a given backward references.
for (i = 0; i < backward_refs->size; ++i) {
const PixOrCopy* const v = &backward_refs->refs[i];
while (VP8LRefsCursorOk(&c)) {
const PixOrCopy* const v = c.cur_pos;
const int ix = (y >> histo_bits) * histo_xsize + (x >> histo_bits);
VP8LHistogramAddSinglePixOrCopy(histograms[ix], v);
x += PixOrCopyLength(v);
@ -438,6 +439,7 @@ static void HistogramBuild(
x -= xsize;
++y;
}
VP8LRefsCursorNext(&c);
}
}