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remove absolute_delta_ field and syntax code

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we'll always encode using absolute value, not relative ones.
    Both methods use the same number of bits, so we'll go for the
    simpler and most robust one.
    + add some extra checks about pic->u/v being NULL.

Change-Id: I98ea01a1a6b133ab3c816c0fbc50e18269bd2098
This commit is contained in:
Pascal Massimino 2011-02-27 10:22:54 -08:00
parent 0744e8420e
commit b65a3e101e
3 changed files with 7 additions and 20 deletions
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19
src/enc/syntax.c
View File

@ -86,24 +86,13 @@ static void PutSegmentHeader(VP8BitWriter* const bw,
int s;
VP8PutBitUniform(bw, hdr->update_map_);
if (VP8PutBitUniform(bw, update_data)) {
const int base_quant = enc->base_quant_;
const int base_strength = enc->filter_hdr_.level_;
VP8PutBitUniform(bw, hdr->absolute_delta_);
// we always use absolute values, not relative ones
VP8PutBitUniform(bw, 1); // (segment_feature_mode = 1. Paragraph 9.3.)
for (s = 0; s < NUM_MB_SEGMENTS; ++s) {
if (hdr->absolute_delta_) {
VP8PutSignedValue(bw, enc->dqm_[s].quant_, 7);
} else {
const int delta = enc->dqm_[s].quant_ - base_quant;
VP8PutSignedValue(bw, delta, 7);
}
VP8PutSignedValue(bw, enc->dqm_[s].quant_, 7);
}
for (s = 0; s < NUM_MB_SEGMENTS; ++s) {
if (hdr->absolute_delta_) {
VP8PutSignedValue(bw, enc->dqm_[s].fstrength_, 6);
} else {
const int delta = enc->dqm_[s].fstrength_ - base_strength;
VP8PutSignedValue(bw, delta, 6);
}
VP8PutSignedValue(bw, enc->dqm_[s].fstrength_, 6);
}
}
if (hdr->update_map_) {

3
src/enc/vp8enci.h
View File

@ -159,9 +159,6 @@ typedef struct {
int num_segments_; // Actual number of segments. 1 segment only = unused.
int update_map_; // whether to update the segment map or not.
// must be 0 if there's only 1 segment.
int absolute_delta_; // if true, segments' filter strength and quantizers
// are not transmitted relatively to
// VP8FilterHeader::level_ and base_quant_
int size_; // bit-cost for transmitting the segment map
} VP8SegmentHeader;

5
src/enc/webpenc.c
View File

@ -55,7 +55,6 @@ static void ResetSegmentHeader(VP8Encoder* const enc) {
VP8SegmentHeader* const hdr = &enc->segment_hdr_;
hdr->num_segments_ = enc->config_->segments;
hdr->update_map_ = (hdr->num_segments_ > 1);
hdr->absolute_delta_ = 1;
hdr->size_ = 0;
}
@ -285,7 +284,9 @@ int WebPEncode(const WebPConfig* const config, WebPPicture* const pic) {
return 0; // bad params
if (!WebPValidateConfig(config))
return 0; // invalid config.
if (pic->width <= 0 || pic->height <= 0 || pic->y == NULL)
if (pic->width <= 0 || pic->height <= 0)
return 0; // invalid parameters
if (pic->y == NULL || pic->u == NULL || pic->v == NULL)
return 0; // invalid parameters
if (pic->width >= MAX_DIMENSION || pic->height >= MAX_DIMENSION)
return 0; // image is too big