BitmapRegionDecoderBench::BitmapRegionDecoderBench(const char* baseName, SkData* encoded,
SkBitmapRegionDecoderInterface::Strategy strategy, SkColorType colorType,
uint32_t sampleSize, const SkIRect& subset)
: fBRD(nullptr)
, fData(SkRef(encoded))
, fStrategy(strategy)
, fColorType(colorType)
, fSampleSize(sampleSize)
, fSubset(subset)
{
// Choose a useful name for the region decoding strategy
const char* strategyName;
switch (strategy) {
case SkBitmapRegionDecoderInterface::kOriginal_Strategy:
strategyName = "Original";
break;
case SkBitmapRegionDecoderInterface::kCanvas_Strategy:
strategyName = "Canvas";
break;
default:
SkASSERT(false);
strategyName = "";
break;
}
// Choose a useful name for the color type
const char* colorName = color_type_to_str(colorType);
fName.printf("BRD_%s_%s_%s", baseName, strategyName, colorName);
if (1 != sampleSize) {
fName.appendf("_%.3f", get_scale_from_sample_size(sampleSize));
}
}
SkISize SkSampledCodec::accountForNativeScaling(int* sampleSizePtr, int* nativeSampleSize) const {
SkISize preSampledSize = this->codec()->getInfo().dimensions();
int sampleSize = *sampleSizePtr;
SkASSERT(sampleSize > 1);
if (nativeSampleSize) {
*nativeSampleSize = 1;
}
// Only JPEG supports native downsampling.
if (this->codec()->getEncodedFormat() == SkEncodedImageFormat::kJPEG) {
// See if libjpeg supports this scale directly
switch (sampleSize) {
case 2:
case 4:
case 8:
// This class does not need to do any sampling.
*sampleSizePtr = 1;
return this->codec()->getScaledDimensions(get_scale_from_sample_size(sampleSize));
default:
break;
}
// Check if sampleSize is a multiple of something libjpeg can support.
int remainder;
const int sampleSizes[] = { 8, 4, 2 };
for (int supportedSampleSize : sampleSizes) {
int actualSampleSize;
SkTDivMod(sampleSize, supportedSampleSize, &actualSampleSize, &remainder);
if (0 == remainder) {
float scale = get_scale_from_sample_size(supportedSampleSize);
// this->codec() will scale to this size.
preSampledSize = this->codec()->getScaledDimensions(scale);
// And then this class will sample it.
*sampleSizePtr = actualSampleSize;
if (nativeSampleSize) {
*nativeSampleSize = supportedSampleSize;
}
break;
}
}
}
return preSampledSize;
}
SkISize SkWebpAdapterCodec::onGetSampledDimensions(int sampleSize) const {
float scale = get_scale_from_sample_size(sampleSize);
return this->codec()->getScaledDimensions(scale);
}
