bool
PalettedRowsAreSolidColor(Decoder* aDecoder,
int32_t aStartRow,
int32_t aRowCount,
uint8_t aColor)
{
RawAccessFrameRef currentFrame = aDecoder->GetCurrentFrameRef();
IntRect frameRect = currentFrame->GetRect();
IntRect solidColorRect(frameRect.x, aStartRow, frameRect.width, aRowCount);
return PalettedRectIsSolidColor(aDecoder, solidColorRect, aColor);
}
bool
PalettedRectIsSolidColor(Decoder* aDecoder, const IntRect& aRect, uint8_t aColor)
{
RawAccessFrameRef currentFrame = aDecoder->GetCurrentFrameRef();
uint8_t* imageData;
uint32_t imageLength;
currentFrame->GetImageData(&imageData, &imageLength);
ASSERT_TRUE_OR_RETURN(imageData, false);
// Clamp to the frame rect. If any pixels outside the frame rect are included,
// we immediately fail, because such pixels don't have any "color" in the
// sense this function measures - they're transparent, and that doesn't
// necessarily correspond to any color palette index at all.
IntRect frameRect = currentFrame->GetRect();
ASSERT_EQ_OR_RETURN(imageLength, uint32_t(frameRect.Area()), false);
IntRect rect = aRect.Intersect(frameRect);
ASSERT_EQ_OR_RETURN(rect.Area(), aRect.Area(), false);
// Translate |rect| by |frameRect.TopLeft()| to reflect the fact that the
// frame rect's offset doesn't actually mean anything in terms of the
// in-memory representation of the surface. The image data starts at the upper
// left corner of the frame rect, in other words.
rect -= frameRect.TopLeft();
// Walk through the image data and make sure that the entire rect has the
// palette index |aColor|.
int32_t rowLength = frameRect.width;
for (int32_t row = rect.y; row < rect.YMost(); ++row) {
for (int32_t col = rect.x; col < rect.XMost(); ++col) {
int32_t i = row * rowLength + col;
ASSERT_EQ_OR_RETURN(aColor, imageData[i], false);
}
}
return true;
}
bool
IsSolidPalettedColor(Decoder* aDecoder, uint8_t aColor)
{
RawAccessFrameRef currentFrame = aDecoder->GetCurrentFrameRef();
return PalettedRectIsSolidColor(aDecoder, currentFrame->GetRect(), aColor);
}
