Temporarily disable encoding of alpha plane with color cache.

This is to avoid triggering the related decoder bug.

Change-Id: I8fa074a5393bcd62aa4a2232cd4e02935e927a89
This commit is contained in:
Urvang Joshi 2015-01-28 15:28:02 -08:00
parent 1d575ccd4e
commit 2db15a9583
3 changed files with 14 additions and 8 deletions

View File

@ -74,7 +74,11 @@ static int EncodeLossless(const uint8_t* const data, int width, int height,
config.quality = 8.f * effort_level;
assert(config.quality >= 0 && config.quality <= 100.f);
ok = (VP8LEncodeStream(&config, &picture, bw) == VP8_ENC_OK);
// TODO(urvang): Temporary fix to avoid generating images that trigger
// a decoder bug related to alpha with color cache.
// See: https://code.google.com/p/webp/issues/detail?id=239
// Need to re-enable this later.
ok = (VP8LEncodeStream(&config, &picture, bw, 0 /*use_cache*/) == VP8_ENC_OK);
WebPPictureFree(&picture);
ok = ok && !bw->error_;
if (!ok) {

View File

@ -748,7 +748,8 @@ static WebPEncodingError EncodeImageInternal(VP8LBitWriter* const bw,
VP8LHashChain* const hash_chain,
VP8LBackwardRefs refs_array[2],
int width, int height, int quality,
int low_effort, int* cache_bits,
int low_effort,
int use_cache, int* cache_bits,
int histogram_bits,
size_t init_byte_position,
int* const hdr_size,
@ -780,7 +781,7 @@ static WebPEncodingError EncodeImageInternal(VP8LBitWriter* const bw,
goto Error;
}
*cache_bits = MAX_COLOR_CACHE_BITS;
*cache_bits = use_cache ? MAX_COLOR_CACHE_BITS : 0;
// 'best_refs' is the reference to the best backward refs and points to one
// of refs_array[0] or refs_array[1].
// Calculate backward references from ARGB image.
@ -1215,7 +1216,7 @@ static void VP8LEncoderDelete(VP8LEncoder* enc) {
WebPEncodingError VP8LEncodeStream(const WebPConfig* const config,
const WebPPicture* const picture,
VP8LBitWriter* const bw) {
VP8LBitWriter* const bw, int use_cache) {
WebPEncodingError err = VP8_ENC_OK;
const int quality = (int)config->quality;
const int low_effort = (config->method == 0);
@ -1293,8 +1294,8 @@ WebPEncodingError VP8LEncodeStream(const WebPConfig* const config,
// Encode and write the transformed image.
err = EncodeImageInternal(bw, enc->argb_, &enc->hash_chain_, enc->refs_,
enc->current_width_, height, quality, low_effort,
&enc->cache_bits_, enc->histo_bits_, byte_position,
&hdr_size, &data_size);
use_cache, &enc->cache_bits_, enc->histo_bits_,
byte_position, &hdr_size, &data_size);
if (err != VP8_ENC_OK) goto Error;
if (picture->stats != NULL) {
@ -1379,7 +1380,7 @@ int VP8LEncodeImage(const WebPConfig* const config,
if (!WebPReportProgress(picture, 5, &percent)) goto UserAbort;
// Encode main image stream.
err = VP8LEncodeStream(config, picture, &bw);
err = VP8LEncodeStream(config, picture, &bw, 1 /*use_cache*/);
if (err != VP8_ENC_OK) goto Error;
// TODO(skal): have a fine-grained progress report in VP8LEncodeStream().

View File

@ -64,9 +64,10 @@ int VP8LEncodeImage(const WebPConfig* const config,
const WebPPicture* const picture);
// Encodes the main image stream using the supplied bit writer.
// If 'use_cache' is false, disables the use of color cache.
WebPEncodingError VP8LEncodeStream(const WebPConfig* const config,
const WebPPicture* const picture,
VP8LBitWriter* const bw);
VP8LBitWriter* const bw, int use_cache);
//------------------------------------------------------------------------------