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Add VP8L prefix to backward ref & histogram methods.

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Change-Id: I8c14fb219a1d7830d3244aa780c91c9964867330
This commit is contained in:
Vikas Arora
2012-04-10 03:56:07 +00:00
committed by James Zern
parent fcba7be2d3
commit 32714ce3be
4 changed files with 147 additions and 154 deletions
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69
src/enc/histogram.h
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@ -36,9 +36,9 @@ typedef struct {
// Backward reference prefix-code histogram.
int distance_[DISTANCE_CODES_MAX];
int palette_code_bits_;
} Histogram;
} VP8LHistogram;
static WEBP_INLINE void HistogramClear(Histogram* const p) {
static WEBP_INLINE void VP8LHistogramClear(VP8LHistogram* const p) {
memset(&p->literal_[0], 0, sizeof(p->literal_));
memset(&p->red_[0], 0, sizeof(p->red_));
memset(&p->blue_[0], 0, sizeof(p->blue_));
@ -46,36 +46,36 @@ static WEBP_INLINE void HistogramClear(Histogram* const p) {
memset(&p->distance_[0], 0, sizeof(p->distance_));
}
static WEBP_INLINE void HistogramInit(Histogram* const p,
static WEBP_INLINE void VP8LHistogramInit(VP8LHistogram* const p,
int palette_code_bits) {
p->palette_code_bits_ = palette_code_bits;
HistogramClear(p);
VP8LHistogramClear(p);
}
// Create the histogram.
//
// The input data is the PixOrCopy data, which models the
// literals, stop codes and backward references (both distances and lengths)
void HistogramBuild(Histogram* const p,
const PixOrCopy* const literal_and_length,
int n_literal_and_length);
void VP8LHistogramCreate(VP8LHistogram* const p,
const PixOrCopy* const literal_and_length,
int n_literal_and_length);
void HistogramAddSinglePixOrCopy(Histogram* const p, const PixOrCopy v);
void VP8LHistogramAddSinglePixOrCopy(VP8LHistogram* const p, const PixOrCopy v);
// Estimate how many bits the combined entropy of literals and distance
// approximately maps to.
double HistogramEstimateBits(const Histogram* const p);
double VP8LHistogramEstimateBits(const VP8LHistogram* const p);
// This function estimates the Huffman dictionary + other block overhead
// size for creating a new deflate block.
double HistogramEstimateBitsHeader(const Histogram* const p);
double VP8LHistogramEstimateBitsHeader(const VP8LHistogram* const p);
// This function estimates the cost in bits excluding the bits needed to
// represent the entropy code itself.
double HistogramEstimateBitsBulk(const Histogram* const p);
double VP8LHistogramEstimateBitsBulk(const VP8LHistogram* const p);
static WEBP_INLINE void HistogramAdd(Histogram* const p,
const Histogram* const a) {
static WEBP_INLINE void VP8LHistogramAdd(VP8LHistogram* const p,
const VP8LHistogram* const a) {
int i;
for (i = 0; i < PIX_OR_COPY_CODES_MAX; ++i) {
p->literal_[i] += a->literal_[i];
@ -90,8 +90,8 @@ static WEBP_INLINE void HistogramAdd(Histogram* const p,
}
}
static WEBP_INLINE void HistogramRemove(Histogram* const p,
const Histogram* const a) {
static WEBP_INLINE void VP8LHistogramRemove(VP8LHistogram* const p,
const VP8LHistogram* const a) {
int i;
for (i = 0; i < PIX_OR_COPY_CODES_MAX; ++i) {
p->literal_[i] -= a->literal_[i];
@ -111,39 +111,38 @@ static WEBP_INLINE void HistogramRemove(Histogram* const p,
}
}
static WEBP_INLINE int HistogramNumPixOrCopyCodes(const Histogram* const p) {
static WEBP_INLINE int VP8LHistogramNumCodes(const VP8LHistogram* const p) {
return 256 + kLengthCodes + (1 << p->palette_code_bits_);
}
void ConvertPopulationCountTableToBitEstimates(
void VP8LConvertPopulationCountTableToBitEstimates(
int n, const int* const population_counts, double* const output);
double ShannonEntropy(const int* const array, int n);
double VP8LShannonEntropy(const int* const array, int n);
// Build a 2d image of histograms, subresolutioned by (1 << histobits) to
// the original image.
int BuildHistogramImage(int xsize, int ysize,
int histobits,
int palette_bits,
const PixOrCopy* backward_refs,
int backward_refs_size,
Histogram*** image,
int* histogram_size);
int VP8LHistogramBuildImage(int xsize, int ysize,
int histobits, int palette_bits,
const PixOrCopy* backward_refs,
int backward_refs_size,
VP8LHistogram*** image,
int* histogram_size);
// Combines several histograms into fewer histograms.
int CombineHistogramImage(Histogram** in,
int in_size,
int quality,
Histogram*** out,
int* out_size);
int VP8LHistogramCombine(VP8LHistogram** in,
int in_size,
int quality,
VP8LHistogram*** out,
int* out_size);
// Moves histograms from one cluster to another if smaller entropy can
// be achieved by doing that.
void RefineHistogramImage(Histogram** raw,
int raw_size,
uint32_t* symbols,
int out_size,
Histogram** out);
void VP8LHistogramRefine(VP8LHistogram** raw,
int raw_size,
uint32_t* symbols,
int out_size,
VP8LHistogram** out);
#if defined(__cplusplus) || defined(c_plusplus)
}