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Restrict histo_bits to ensure histo_image size is under 32MB

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Change-Id: I75ccb65d56ee060b649de714287e71611a92c8e9
This commit is contained in:
Vikas Arora 2012-04-25 11:14:11 +00:00 committed by James Zern
parent 8415ddf3be
commit fbb501b8ee
1 changed files with 19 additions and 4 deletions
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23
src/enc/vp8l.c
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@ -27,6 +27,8 @@
extern "C" { extern "C" {
#endif #endif
#define MAX_HUFF_IMAGE_SIZE (32 * 1024 * 1024)
static const int kImageSizeBits = 14; static const int kImageSizeBits = 14;
static int CompareColors(const void* p1, const void* p2) { static int CompareColors(const void* p1, const void* p2) {
@ -985,10 +987,25 @@ static WebPEncodingError WriteImage(VP8LEncoder* const enc,
return err; return err;
} }
static int GetHistoBits(const WebPConfig* const config,
const WebPPicture* const pic) {
const int width = pic->width;
const int height = pic->height;
const int hist_size = sizeof(VP8LHistogram);
int histo_bits = 9 - (int)(config->quality / 16.f + .5f);
while (1) {
const size_t huff_image_size = VP8LSubSampleSize(width, histo_bits) *
VP8LSubSampleSize(height, histo_bits) *
hist_size;
if (huff_image_size <= MAX_HUFF_IMAGE_SIZE) break;
++histo_bits;
}
return (histo_bits < 3) ? 3 : (histo_bits > 10) ? 10 : histo_bits;
}
static VP8LEncoder* InitVP8LEncoder(const WebPConfig* const config, static VP8LEncoder* InitVP8LEncoder(const WebPConfig* const config,
WebPPicture* const picture) { WebPPicture* const picture) {
const int method = config->method; const int method = config->method;
const int histo_bits = 9 - (int)(config->quality / 16.f + .5f);
VP8LEncoder* enc = (VP8LEncoder*)malloc(sizeof(*enc)); VP8LEncoder* enc = (VP8LEncoder*)malloc(sizeof(*enc));
if (enc == NULL) { if (enc == NULL) {
WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY); WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
@ -999,10 +1016,8 @@ static VP8LEncoder* InitVP8LEncoder(const WebPConfig* const config,
enc->config_ = config; enc->config_ = config;
enc->pic_ = picture; enc->pic_ = picture;
enc->use_lz77_ = 1; enc->use_lz77_ = 1;
enc->histo_bits_ =
(histo_bits < 3) ? 3 : (histo_bits > 8) ? 8 : histo_bits;
enc->transform_bits_ = (method < 4) ? 5 : (method > 4) ? 3 : 4; enc->transform_bits_ = (method < 4) ? 5 : (method > 4) ? 3 : 4;
enc->histo_bits_ = GetHistoBits(config, picture);
return enc; return enc;
} }