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more consolidation: introduce VP8LHistogramSet

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VP8LHistogramSet is container for pointers to histograms that
we can shuffle around. Allocation is one big chunk of memory.
Downside is that we don't de-allocate memory on-the-go during
HistogramRefine().

+ renamed HistogramRefine() into HistogramRemap(), so we don't
confuse with "HistogramCombine"
+ made VP8LHistogramClear() static.

Change-Id: Idf1a748a871c3b942cca5c8050072ccd82c7511d
This commit is contained in:
Pascal Massimino
2012-04-30 19:46:22 +00:00
committed by James Zern
parent 1a210ef1a9
commit d0d88990d8
3 changed files with 121 additions and 126 deletions
Download Patch File Download Diff File Expand all files Collapse all files

159
src/enc/histogram.c
View File

@ -17,20 +17,7 @@
#include "./histogram.h"
#include "../dsp/lossless.h"
void VP8LHistogramCreate(VP8LHistogram* const p,
const VP8LBackwardRefs* const refs,
int palette_code_bits) {
int i;
if (palette_code_bits >= 0) {
p->palette_code_bits_ = palette_code_bits;
}
VP8LHistogramClear(p);
for (i = 0; i < refs->size; ++i) {
VP8LHistogramAddSinglePixOrCopy(p, &refs->refs[i]);
}
}
void VP8LHistogramClear(VP8LHistogram* const p) {
static void HistogramClear(VP8LHistogram* const p) {
memset(p->literal_, 0, sizeof(p->literal_));
memset(p->red_, 0, sizeof(p->red_));
memset(p->blue_, 0, sizeof(p->blue_));
@ -39,38 +26,52 @@ void VP8LHistogramClear(VP8LHistogram* const p) {
p->bit_cost_ = 0;
}
void VP8LHistogramCreate(VP8LHistogram* const p,
const VP8LBackwardRefs* const refs,
int palette_code_bits) {
int i;
if (palette_code_bits >= 0) {
p->palette_code_bits_ = palette_code_bits;
}
HistogramClear(p);
for (i = 0; i < refs->size; ++i) {
VP8LHistogramAddSinglePixOrCopy(p, &refs->refs[i]);
}
}
void VP8LHistogramInit(VP8LHistogram* const p, int palette_code_bits) {
p->palette_code_bits_ = palette_code_bits;
VP8LHistogramClear(p);
HistogramClear(p);
}
VP8LHistogram** VP8LAllocateHistograms(int size, int cache_bits) {
VP8LHistogramSet* VP8LAllocateHistogramSet(int size, int cache_bits) {
int i;
VP8LHistogram** const histos =
(VP8LHistogram**)calloc(size, sizeof(*histos));
if (histos == NULL) return NULL;
VP8LHistogramSet* set;
VP8LHistogram* bulk;
const size_t total_size = sizeof(*set)
+ size * sizeof(*set->histograms)
+ size * sizeof(**set->histograms);
uint8_t* memory = (uint8_t*)malloc(total_size);
if (memory == NULL) return NULL;
set = (VP8LHistogramSet*)memory;
memory += sizeof(*set);
set->histograms = (VP8LHistogram**)memory;
memory += size * sizeof(*set->histograms);
bulk = (VP8LHistogram*)memory;
set->max_size = size;
set->size = size;
for (i = 0; i < size; ++i) {
histos[i] = (VP8LHistogram*)malloc(sizeof(**histos));
if (histos[i] == NULL) {
VP8LDeleteHistograms(histos, i);
return NULL;
}
VP8LHistogramInit(histos[i], cache_bits);
set->histograms[i] = bulk + i;
VP8LHistogramInit(set->histograms[i], cache_bits);
}
return histos;
return set;
}
void VP8LDeleteHistograms(VP8LHistogram** const histograms, int size) {
if (histograms != NULL) {
int i;
for (i = 0; i < size; ++i) free(histograms[i]);
free(histograms);
}
}
// -----------------------------------------------------------------------------
void VP8LConvertPopulationCountTableToBitEstimates(
int num_symbols,
const int* const population_counts,
int num_symbols, const int* const population_counts,
double* const output) {
int sum = 0;
int nonzeros = 0;
@ -241,7 +242,7 @@ double VP8LHistogramEstimateBitsHeader(const VP8LHistogram* const p) {
static void HistogramBuildImage(int xsize, int histo_bits,
const VP8LBackwardRefs* const backward_refs,
VP8LHistogram** const image) {
VP8LHistogramSet* const image) {
int i;
int x = 0, y = 0;
const int histo_xsize =
@ -251,7 +252,7 @@ static void HistogramBuildImage(int xsize, int histo_bits,
const int ix =
(histo_bits > 0) ? (y >> histo_bits) * histo_xsize + (x >> histo_bits)
: 0;
VP8LHistogramAddSinglePixOrCopy(image[ix], v);
VP8LHistogramAddSinglePixOrCopy(image->histograms[ix], v);
x += PixOrCopyLength(v);
while (x >= xsize) {
x -= xsize;
@ -260,27 +261,25 @@ static void HistogramBuildImage(int xsize, int histo_bits,
}
}
static int HistogramCombine(VP8LHistogram* const * const in, int in_size,
int num_pairs, VP8LHistogram** const out,
int* const final_out_size) {
static int HistogramCombine(const VP8LHistogramSet* const in,
VP8LHistogramSet* const out, int num_pairs) {
int ok = 0;
int i, iter;
unsigned int seed = 0;
int tries_with_no_success = 0;
const int min_cluster_size = 2;
int out_size = in_size;
const int outer_iters = in_size * 3;
int out_size = in->size;
const int outer_iters = in->size * 3;
VP8LHistogram* const histos = (VP8LHistogram*)malloc(2 * sizeof(*histos));
VP8LHistogram* cur_combo = histos + 0; // trial merged histogram
VP8LHistogram* best_combo = histos + 1; // best merged histogram so far
if (histos == NULL) goto End;
// Copy histograms from in[] to out[].
for (i = 0; i < in_size; ++i) {
out[i] = (VP8LHistogram*)malloc(sizeof(*(out[i])));
if (out[i] == NULL) goto End;
*(out[i]) = *(in[i]);
out[i]->bit_cost_ = in[i]->bit_cost_ = VP8LHistogramEstimateBits(out[i]);
assert(in->size <= out->size);
for (i = 0; i < in->size; ++i) {
in->histograms[i]->bit_cost_ = VP8LHistogramEstimateBits(in->histograms[i]);
*out->histograms[i] = *in->histograms[i];
}
// Collapse similar histograms in 'out'.
@ -299,12 +298,13 @@ static int HistogramCombine(VP8LHistogram* const * const in, int in_size,
if (idx1 == idx2) {
continue;
}
*cur_combo = *out[idx1];
VP8LHistogramAdd(cur_combo, out[idx2]);
*cur_combo = *out->histograms[idx1];
VP8LHistogramAdd(cur_combo, out->histograms[idx2]);
cur_combo->bit_cost_ = VP8LHistogramEstimateBits(cur_combo);
// Calculate cost reduction on combining.
curr_cost_diff = cur_combo->bit_cost_
- out[idx1]->bit_cost_ - out[idx2]->bit_cost_;
- out->histograms[idx1]->bit_cost_
- out->histograms[idx2]->bit_cost_;
if (best_cost_diff > curr_cost_diff) { // found a better pair?
{ // swap cur/best combo histograms
VP8LHistogram* const tmp = cur_combo;
@ -318,13 +318,12 @@ static int HistogramCombine(VP8LHistogram* const * const in, int in_size,
}
if (best_cost_diff < 0.0) {
*out[best_idx1] = *best_combo;
*out->histograms[best_idx1] = *best_combo;
// swap best_idx2 slot with last one (which is now unused)
free(out[best_idx2]);
--out_size;
if (best_idx2 != out_size) {
out[best_idx2] = out[out_size];
out[out_size] = NULL; // just for sanity check.
out->histograms[best_idx2] = out->histograms[out_size];
out->histograms[out_size] = NULL; // just for sanity check.
}
tries_with_no_success = 0;
}
@ -332,7 +331,7 @@ static int HistogramCombine(VP8LHistogram* const * const in, int in_size,
break;
}
}
*final_out_size = out_size;
out->size = out_size;
ok = 1;
End:
@ -359,18 +358,19 @@ static double HistogramDistance(const VP8LHistogram* const square_histogram,
return new_bit_cost - previous_bit_cost;
}
// Find the best 'out' histogram for each of the raw histograms.
// Find the best 'out' histogram for each of the 'in' histograms.
// Note: we assume that out[]->bit_cost_ is already up-to-date.
static void HistogramRefine(VP8LHistogram* const * const raw, int raw_size,
uint16_t* const symbols,
VP8LHistogram** const out, int out_size) {
static void HistogramRemap(const VP8LHistogramSet* const in,
const VP8LHistogramSet* const out,
uint16_t* const symbols) {
int i;
for (i = 0; i < raw_size; ++i) {
for (i = 0; i < in->size; ++i) {
int best_out = 0;
double best_bits = HistogramDistance(raw[i], out[0]);
double best_bits = HistogramDistance(in->histograms[i], out->histograms[0]);
int k;
for (k = 1; k < out_size; ++k) {
const double cur_bits = HistogramDistance(raw[i], out[k]);
for (k = 1; k < out->size; ++k) {
const double cur_bits =
HistogramDistance(in->histograms[i], out->histograms[k]);
if (cur_bits < best_bits) {
best_bits = cur_bits;
best_out = k;
@ -380,47 +380,40 @@ static void HistogramRefine(VP8LHistogram* const * const raw, int raw_size,
}
// Recompute each out based on raw and symbols.
for (i = 0; i < out_size; ++i) {
VP8LHistogramClear(out[i]);
for (i = 0; i < out->size; ++i) {
HistogramClear(out->histograms[i]);
}
for (i = 0; i < raw_size; ++i) {
VP8LHistogramAdd(out[symbols[i]], raw[i]);
for (i = 0; i < in->size; ++i) {
VP8LHistogramAdd(out->histograms[symbols[i]], in->histograms[i]);
}
}
int VP8LGetHistoImageSymbols(int xsize, int ysize,
const VP8LBackwardRefs* const refs,
int quality, int histo_bits, int cache_bits,
VP8LHistogram** const histogram_image,
int* const histo_image_raw_size_ptr,
VP8LHistogramSet* const image_in,
uint16_t* const histogram_symbols) {
int ok = 0;
const int histo_xsize = histo_bits ? VP8LSubSampleSize(xsize, histo_bits) : 1;
const int histo_ysize = histo_bits ? VP8LSubSampleSize(ysize, histo_bits) : 1;
const int num_histo_pairs = 10 + quality / 2; // For HistogramCombine().
const int histo_image_raw_size = histo_xsize * histo_ysize;
VP8LHistogram** const histo_image_raw =
VP8LAllocateHistograms(histo_image_raw_size, cache_bits);
if (histo_image_raw == NULL) return 0;
*histo_image_raw_size_ptr = histo_image_raw_size; // initial guess.
VP8LHistogramSet* const image_out =
VP8LAllocateHistogramSet(histo_image_raw_size, cache_bits);
if (image_out == NULL) return 0;
// Build histogram image.
HistogramBuildImage(xsize, histo_bits, refs, histo_image_raw);
HistogramBuildImage(xsize, histo_bits, refs, image_out);
// Collapse similar histograms.
if (!HistogramCombine(histo_image_raw, histo_image_raw_size, num_histo_pairs,
histogram_image, histo_image_raw_size_ptr)) {
if (!HistogramCombine(image_out, image_in, num_histo_pairs)) {
goto Error;
}
// Refine histogram image.
HistogramRefine(histo_image_raw, histo_image_raw_size, histogram_symbols,
histogram_image, *histo_image_raw_size_ptr);
// Find the optimal map from original histograms to the final ones.
HistogramRemap(image_out, image_in, histogram_symbols);
ok = 1;
Error:
if (!ok) {
VP8LDeleteHistograms(histogram_image, *histo_image_raw_size_ptr);
}
VP8LDeleteHistograms(histo_image_raw, histo_image_raw_size);
free(image_out);
return ok;
}