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Reducing emerging palette size from 11 to 9 bits.

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This is required to reduce memory used to construct histo_image.

Change-Id: I491a06e10a3e3f3d8a00ecec286394378283ffea
This commit is contained in:
Vikas Arora 2012-04-26 10:25:49 +00:00 committed by James Zern
parent bfc73db4a8
commit b39e7487a7
2 changed files with 5 additions and 3 deletions
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2
src/enc/backward_references.c
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@ -751,7 +751,7 @@ int VP8LCalculateEstimateForCacheSize(
stream, &stream_size)) {
goto Error;
}
for (cache_bits = 0; cache_bits < 12; ++cache_bits) {
for (cache_bits = 0; cache_bits <= kColorCacheBitsMax; ++cache_bits) {
double cur_entropy;
VP8LHistogram histo;
VP8LHistogramInit(&histo, cache_bits);

6
src/enc/backward_references.h
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@ -27,8 +27,10 @@ extern "C" {
// Compression constants
#define CODE_LENGTH_CODES 19
static const int kLengthCodes = 24;
static const int kColorCacheBitsMax = 11;
#define PIX_OR_COPY_CODES_MAX (256 + 24 + (1 << 11))
// The spec allows 11, we use 9 bits to reduce memory consumption in encoding.
// Having 9 instead of 11 removes about 0.25 % of compression density.
static const int kColorCacheBitsMax = 9;
#define PIX_OR_COPY_CODES_MAX (256 + 24 + (1 << 9))
static const int kMaxLength = 4096;
// use GNU builtins where available.