void SkJpegCodec::initializeSwizzler(const SkImageInfo& dstInfo, const Options& options) {
// libjpeg-turbo may have already performed color conversion. We must indicate the
// appropriate format to the swizzler.
SkEncodedInfo swizzlerInfo = this->getEncodedInfo();
bool preSwizzled = true;
switch (fDecoderMgr->dinfo()->out_color_space) {
case JCS_RGB:
preSwizzled = false;
swizzlerInfo = SkEncodedInfo::Make(SkEncodedInfo::kRGB_Color,
swizzlerInfo.alpha(),
swizzlerInfo.bitsPerComponent());
break;
case JCS_CMYK:
preSwizzled = false;
swizzlerInfo = SkEncodedInfo::Make(SkEncodedInfo::kInvertedCMYK_Color,
swizzlerInfo.alpha(),
swizzlerInfo.bitsPerComponent());
break;
default:
break;
}
Options swizzlerOptions = options;
if (options.fSubset) {
// Use fSwizzlerSubset if this is a subset decode. This is necessary in the case
// where libjpeg-turbo provides a subset and then we need to subset it further.
// Also, verify that fSwizzlerSubset is initialized and valid.
SkASSERT(!fSwizzlerSubset.isEmpty() && fSwizzlerSubset.x() <= options.fSubset->x() &&
fSwizzlerSubset.width() == options.fSubset->width());
swizzlerOptions.fSubset = &fSwizzlerSubset;
}
fSwizzler.reset(SkSwizzler::CreateSwizzler(swizzlerInfo, nullptr, dstInfo, swizzlerOptions,
nullptr, preSwizzled));
SkASSERT(fSwizzler);
}
