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write an ad-hoc EncodeImageInternal variant

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Used when we don't code a Huffman Image.
-> Simplify the code quite some because we don't have to
deal with special cases of histo bits

Change-Id: I0c3f46cbf3b501e021c093e07253e7404c01ff4f
This commit is contained in:
Pascal Massimino
2012-06-08 11:52:31 -07:00
parent eaee9e79f7
commit 3697b5ceb2
3 changed files with 94 additions and 47 deletions
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50
src/enc/histogram.c
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@ -40,17 +40,22 @@ static void HistogramClear(VP8LHistogram* const p) {
p->bit_cost_ = 0;
}
void VP8LHistogramStoreRefs(const VP8LBackwardRefs* const refs,
VP8LHistogram* const histo) {
int i;
for (i = 0; i < refs->size; ++i) {
VP8LHistogramAddSinglePixOrCopy(histo, &refs->refs[i]);
}
}
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]);
}
VP8LHistogramStoreRefs(refs, p);
}
void VP8LHistogramInit(VP8LHistogram* const p, int palette_code_bits) {
@ -112,24 +117,24 @@ void VP8LConvertPopulationCountTableToBitEstimates(
}
}
void VP8LHistogramAddSinglePixOrCopy(VP8LHistogram* const p,
void VP8LHistogramAddSinglePixOrCopy(VP8LHistogram* const histo,
const PixOrCopy* const v) {
if (PixOrCopyIsLiteral(v)) {
++p->alpha_[PixOrCopyLiteral(v, 3)];
++p->red_[PixOrCopyLiteral(v, 2)];
++p->literal_[PixOrCopyLiteral(v, 1)];
++p->blue_[PixOrCopyLiteral(v, 0)];
++histo->alpha_[PixOrCopyLiteral(v, 3)];
++histo->red_[PixOrCopyLiteral(v, 2)];
++histo->literal_[PixOrCopyLiteral(v, 1)];
++histo->blue_[PixOrCopyLiteral(v, 0)];
} else if (PixOrCopyIsCacheIdx(v)) {
int literal_ix = 256 + NUM_LENGTH_CODES + PixOrCopyCacheIdx(v);
++p->literal_[literal_ix];
++histo->literal_[literal_ix];
} else {
int code, extra_bits_count, extra_bits_value;
PrefixEncode(PixOrCopyLength(v),
&code, &extra_bits_count, &extra_bits_value);
++p->literal_[256 + code];
++histo->literal_[256 + code];
PrefixEncode(PixOrCopyDistance(v),
&code, &extra_bits_count, &extra_bits_value);
++p->distance_[code];
++histo->distance_[code];
}
}
@ -186,11 +191,11 @@ static double BitsEntropy(const int* const array, int n) {
}
double VP8LHistogramEstimateBitsBulk(const VP8LHistogram* const p) {
double retval = BitsEntropy(&p->literal_[0], VP8LHistogramNumCodes(p)) +
BitsEntropy(&p->red_[0], 256) +
BitsEntropy(&p->blue_[0], 256) +
BitsEntropy(&p->alpha_[0], 256) +
BitsEntropy(&p->distance_[0], NUM_DISTANCE_CODES);
double retval = BitsEntropy(&p->literal_[0], VP8LHistogramNumCodes(p))
+ BitsEntropy(&p->red_[0], 256)
+ BitsEntropy(&p->blue_[0], 256)
+ BitsEntropy(&p->alpha_[0], 256)
+ BitsEntropy(&p->distance_[0], NUM_DISTANCE_CODES);
// Compute the extra bits cost.
int i;
for (i = 2; i < NUM_LENGTH_CODES - 2; ++i) {
@ -259,14 +264,13 @@ static void HistogramBuildImage(int xsize, int histo_bits,
VP8LHistogramSet* const image) {
int i;
int x = 0, y = 0;
const int histo_xsize =
(histo_bits > 0) ? VP8LSubSampleSize(xsize, histo_bits) : 1;
const int histo_xsize = VP8LSubSampleSize(xsize, histo_bits);
VP8LHistogram** const histograms = image->histograms;
assert(histo_bits > 0);
for (i = 0; i < backward_refs->size; ++i) {
const PixOrCopy* const v = &backward_refs->refs[i];
const int ix =
(histo_bits > 0) ? (y >> histo_bits) * histo_xsize + (x >> histo_bits)
: 0;
VP8LHistogramAddSinglePixOrCopy(image->histograms[ix], v);
const int ix = (y >> histo_bits) * histo_xsize + (x >> histo_bits);
VP8LHistogramAddSinglePixOrCopy(histograms[ix], v);
x += PixOrCopyLength(v);
while (x >= xsize) {
x -= xsize;