| /* |
| * Copyright 2015 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "SkAndroidCodec.h" |
| #include "SkBitmapRegionCodec.h" |
| #include "SkBitmapRegionDecoderPriv.h" |
| #include "SkCodecPriv.h" |
| #include "SkPixelRef.h" |
| |
| SkBitmapRegionCodec::SkBitmapRegionCodec(SkAndroidCodec* codec) |
| : INHERITED(codec->getInfo().width(), codec->getInfo().height()) |
| , fCodec(codec) |
| {} |
| |
| bool SkBitmapRegionCodec::decodeRegion(SkBitmap* bitmap, SkBRDAllocator* allocator, |
| const SkIRect& desiredSubset, int sampleSize, SkColorType prefColorType, |
| bool requireUnpremul) { |
| |
| // Fix the input sampleSize if necessary. |
| if (sampleSize < 1) { |
| sampleSize = 1; |
| } |
| |
| // The size of the output bitmap is determined by the size of the |
| // requested subset, not by the size of the intersection of the subset |
| // and the image dimensions. |
| // If inputX is negative, we will need to place decoded pixels into the |
| // output bitmap starting at a left offset. Call this outX. |
| // If outX is non-zero, subsetX must be zero. |
| // If inputY is negative, we will need to place decoded pixels into the |
| // output bitmap starting at a top offset. Call this outY. |
| // If outY is non-zero, subsetY must be zero. |
| int outX; |
| int outY; |
| SkIRect subset = desiredSubset; |
| SubsetType type = adjust_subset_rect(fCodec->getInfo().dimensions(), &subset, &outX, &outY); |
| if (SubsetType::kOutside_SubsetType == type) { |
| return false; |
| } |
| |
| // Ask the codec for a scaled subset |
| if (!fCodec->getSupportedSubset(&subset)) { |
| SkCodecPrintf("Error: Could not get subset.\n"); |
| return false; |
| } |
| SkISize scaledSize = fCodec->getSampledSubsetDimensions(sampleSize, subset); |
| |
| // Create the image info for the decode |
| SkColorType dstColorType = fCodec->computeOutputColorType(prefColorType); |
| SkAlphaType dstAlphaType = fCodec->computeOutputAlphaType(requireUnpremul); |
| |
| // Enable legacy behavior to avoid any gamma correction. Android's assets are |
| // adjusted to expect a non-gamma correct premultiply. |
| sk_sp<SkColorSpace> colorSpace = nullptr; |
| SkImageInfo decodeInfo = SkImageInfo::Make(scaledSize.width(), scaledSize.height(), |
| dstColorType, dstAlphaType, colorSpace); |
| |
| // Construct a color table for the decode if necessary |
| sk_sp<SkColorTable> colorTable(nullptr); |
| int maxColors = 256; |
| SkPMColor colors[256]; |
| if (kIndex_8_SkColorType == dstColorType) { |
| colorTable.reset(new SkColorTable(colors, maxColors)); |
| } |
| |
| // Initialize the destination bitmap |
| int scaledOutX = 0; |
| int scaledOutY = 0; |
| int scaledOutWidth = scaledSize.width(); |
| int scaledOutHeight = scaledSize.height(); |
| if (SubsetType::kPartiallyInside_SubsetType == type) { |
| scaledOutX = outX / sampleSize; |
| scaledOutY = outY / sampleSize; |
| // We need to be safe here because getSupportedSubset() may have modified the subset. |
| const int extraX = SkTMax(0, desiredSubset.width() - outX - subset.width()); |
| const int extraY = SkTMax(0, desiredSubset.height() - outY - subset.height()); |
| const int scaledExtraX = extraX / sampleSize; |
| const int scaledExtraY = extraY / sampleSize; |
| scaledOutWidth += scaledOutX + scaledExtraX; |
| scaledOutHeight += scaledOutY + scaledExtraY; |
| } |
| SkImageInfo outInfo = decodeInfo.makeWH(scaledOutWidth, scaledOutHeight); |
| if (kGray_8_SkColorType == dstColorType) { |
| // The legacy implementations of BitmapFactory and BitmapRegionDecoder |
| // used kAlpha8 for grayscale images (before kGray8 existed). While |
| // the codec recognizes kGray8, we need to decode into a kAlpha8 |
| // bitmap in order to avoid a behavior change. |
| outInfo = outInfo.makeColorType(kAlpha_8_SkColorType).makeAlphaType(kPremul_SkAlphaType); |
| } |
| bitmap->setInfo(outInfo); |
| if (!bitmap->tryAllocPixels(allocator, colorTable.get())) { |
| SkCodecPrintf("Error: Could not allocate pixels.\n"); |
| return false; |
| } |
| |
| // Zero the bitmap if the region is not completely within the image. |
| // TODO (msarett): Can we make this faster by implementing it to only |
| // zero parts of the image that we won't overwrite with |
| // pixels? |
| SkCodec::ZeroInitialized zeroInit = allocator ? allocator->zeroInit() : |
| SkCodec::kNo_ZeroInitialized; |
| if (SubsetType::kPartiallyInside_SubsetType == type && |
| SkCodec::kNo_ZeroInitialized == zeroInit) { |
| void* pixels = bitmap->getPixels(); |
| size_t bytes = outInfo.getSafeSize(bitmap->rowBytes()); |
| memset(pixels, 0, bytes); |
| } |
| |
| // Decode into the destination bitmap |
| SkAndroidCodec::AndroidOptions options; |
| options.fSampleSize = sampleSize; |
| options.fSubset = ⊂ |
| options.fColorPtr = colors; |
| options.fColorCount = &maxColors; |
| options.fZeroInitialized = zeroInit; |
| void* dst = bitmap->getAddr(scaledOutX, scaledOutY); |
| |
| SkCodec::Result result = fCodec->getAndroidPixels(decodeInfo, dst, bitmap->rowBytes(), |
| &options); |
| if (SkCodec::kSuccess != result && SkCodec::kIncompleteInput != result) { |
| SkCodecPrintf("Error: Could not get pixels.\n"); |
| return false; |
| } |
| |
| // Intialize the color table |
| if (kIndex_8_SkColorType == dstColorType) { |
| colorTable->dangerous_overwriteColors(colors, maxColors); |
| } |
| |
| return true; |
| } |
| |
| bool SkBitmapRegionCodec::conversionSupported(SkColorType colorType) { |
| // Enable legacy behavior. |
| sk_sp<SkColorSpace> colorSpace = nullptr; |
| SkImageInfo dstInfo = fCodec->getInfo().makeColorType(colorType).makeColorSpace(colorSpace); |
| return conversion_possible(dstInfo, fCodec->getInfo()); |
| } |