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Merge "Fix bug in VP8LCalculateEstimateForCacheSize."

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pascal massimino 2014-10-27 02:31:10 -07:00 committed by Gerrit Code Review
commit 53b096c0d7
2 changed files with 21 additions and 12 deletions
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19
src/enc/backward_references.c
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@ -927,33 +927,44 @@ int VP8LCalculateEstimateForCacheSize(const uint32_t* const argb,
int eval_high = 1; int eval_high = 1;
double entropy_low = MAX_ENTROPY; double entropy_low = MAX_ENTROPY;
double entropy_high = MAX_ENTROPY; double entropy_high = MAX_ENTROPY;
const double cost_mul = 5e-4;
int cache_bits_low = 0; int cache_bits_low = 0;
int cache_bits_high = MAX_COLOR_CACHE_BITS; int cache_bits_high = *best_cache_bits;
assert(cache_bits_high <= MAX_COLOR_CACHE_BITS);
if (cache_bits_high == 0) {
// Local color cache is disabled.
return 1;
}
if (!BackwardReferencesHashChain(xsize, ysize, argb, 0, quality, hash_chain, if (!BackwardReferencesHashChain(xsize, ysize, argb, 0, quality, hash_chain,
refs)) { refs)) {
return 0; return 0;
} }
// Do a binary search to find the optimal entropy for cache_bits. // Do a binary search to find the optimal entropy for cache_bits.
while (cache_bits_high - cache_bits_low > 1) { while (eval_low || eval_high) {
if (eval_low) { if (eval_low) {
entropy_low = entropy_low =
ComputeCacheEntropy(argb, xsize, ysize, refs, cache_bits_low); ComputeCacheEntropy(argb, xsize, ysize, refs, cache_bits_low);
entropy_low += entropy_low * cache_bits_low * cost_mul;
eval_low = 0; eval_low = 0;
} }
if (eval_high) { if (eval_high) {
entropy_high = entropy_high =
ComputeCacheEntropy(argb, xsize, ysize, refs, cache_bits_high); ComputeCacheEntropy(argb, xsize, ysize, refs, cache_bits_high);
entropy_high += entropy_high * cache_bits_high * cost_mul;
eval_high = 0; eval_high = 0;
} }
if (entropy_high < entropy_low) { if (entropy_high < entropy_low) {
const int prev_cache_bits_low = cache_bits_low;
*best_cache_bits = cache_bits_high; *best_cache_bits = cache_bits_high;
cache_bits_low = (cache_bits_low + cache_bits_high) / 2; cache_bits_low = (cache_bits_low + cache_bits_high) / 2;
eval_low = 1; if (cache_bits_low != prev_cache_bits_low) eval_low = 1;
} else { } else {
*best_cache_bits = cache_bits_low; *best_cache_bits = cache_bits_low;
cache_bits_high = (cache_bits_low + cache_bits_high) / 2; cache_bits_high = (cache_bits_low + cache_bits_high) / 2;
eval_high = 1; if (cache_bits_high != cache_bits_low) eval_high = 1;
} }
} }
return 1; return 1;

4
src/enc/vp8l.c
View File

@ -284,7 +284,7 @@ static int GetTransformBits(int method, int histo_bits) {
static int GetCacheBits(int use_palette, float quality) { static int GetCacheBits(int use_palette, float quality) {
// Color cache is disabled for compression at lower quality or when a palette // Color cache is disabled for compression at lower quality or when a palette
// is used. // is used.
return (use_palette || (quality <= 25.f)) ? 0 : 7; return (use_palette || (quality <= 25.f)) ? 0 : MAX_COLOR_CACHE_BITS;
} }
static int EvalSubtractGreenForPalette(int palette_size, float quality) { static int EvalSubtractGreenForPalette(int palette_size, float quality) {
@ -1309,14 +1309,12 @@ WebPEncodingError VP8LEncodeStream(const WebPConfig* const config,
// --------------------------------------------------------------------------- // ---------------------------------------------------------------------------
// Estimate the color cache size. // Estimate the color cache size.
if (enc->cache_bits_ > 0) {
if (!VP8LCalculateEstimateForCacheSize(enc->argb_, enc->current_width_, if (!VP8LCalculateEstimateForCacheSize(enc->argb_, enc->current_width_,
height, quality, &enc->hash_chain_, height, quality, &enc->hash_chain_,
&enc->refs_[0], &enc->cache_bits_)) { &enc->refs_[0], &enc->cache_bits_)) {
err = VP8_ENC_ERROR_OUT_OF_MEMORY; err = VP8_ENC_ERROR_OUT_OF_MEMORY;
goto Error; goto Error;
} }
}
// --------------------------------------------------------------------------- // ---------------------------------------------------------------------------
// Encode and write the transformed image. // Encode and write the transformed image.