blob: a2fe6a40efd78dedc19f6df9ab3c773ce5110d17 [file] [log] [blame]
* Copyright 2016 Google Inc.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
#include "SkImageGeneratorCG.h"
#include <ApplicationServices/ApplicationServices.h>
#include <CoreGraphics/CoreGraphics.h>
#include <ImageIO/ImageIO.h>
#include <MobileCoreServices/MobileCoreServices.h>
static CGImageSourceRef data_to_CGImageSrc(SkData* data) {
CGDataProviderRef cgData = CGDataProviderCreateWithData(data, data->data(), data->size(),
if (!cgData) {
return nullptr;
CGImageSourceRef imageSrc = CGImageSourceCreateWithDataProvider(cgData, 0);
return imageSrc;
SkImageGenerator* SkImageGeneratorCG::NewFromEncodedCG(SkData* data) {
CGImageSourceRef imageSrc = data_to_CGImageSrc(data);
if (!imageSrc) {
return nullptr;
// Make sure we call CFRelease to free the imageSrc. Since CFRelease actually takes
// a const void*, we must cast the imageSrc to a const void*.
SkAutoTCallVProc<const void, CFRelease> autoImageSrc(imageSrc);
CFDictionaryRef properties = CGImageSourceCopyPropertiesAtIndex(imageSrc, 0, nullptr);
if (!properties) {
return nullptr;
CFNumberRef widthRef = (CFNumberRef) (CFDictionaryGetValue(properties,
CFNumberRef heightRef = (CFNumberRef) (CFDictionaryGetValue(properties,
if (nullptr == widthRef || nullptr == heightRef) {
return nullptr;
bool hasAlpha = (bool) (CFDictionaryGetValue(properties,
int width, height;
if (!CFNumberGetValue(widthRef, kCFNumberIntType, &width) ||
!CFNumberGetValue(heightRef, kCFNumberIntType, &height)) {
return nullptr;
SkAlphaType alphaType = hasAlpha ? kPremul_SkAlphaType : kOpaque_SkAlphaType;
SkImageInfo info = SkImageInfo::MakeS32(width, height, alphaType);
// FIXME: We have the opportunity to extract color space information here,
// though I think it makes sense to wait until we understand how
// we want to communicate it to the generator.
return new SkImageGeneratorCG(info, autoImageSrc.release(), data);
SkImageGeneratorCG::SkImageGeneratorCG(const SkImageInfo& info, const void* imageSrc, SkData* data)
, fImageSrc(imageSrc)
, fData(SkRef(data))
SkData* SkImageGeneratorCG::onRefEncodedData() {
return SkRef(fData.get());
bool SkImageGeneratorCG::onGetPixels(const SkImageInfo& info, void* pixels, size_t rowBytes,
const Options&) {
if (kN32_SkColorType != info.colorType()) {
// FIXME: Support other colorTypes.
return false;
switch (info.alphaType()) {
case kOpaque_SkAlphaType:
if (kOpaque_SkAlphaType != this->getInfo().alphaType()) {
return false;
case kPremul_SkAlphaType:
return false;
CGImageRef image = CGImageSourceCreateImageAtIndex((CGImageSourceRef) fImageSrc.get(), 0,
if (!image) {
return false;
SkAutoTCallVProc<CGImage, CGImageRelease> autoImage(image);
// FIXME: Using this function (as opposed to swizzling ourselves) greatly
// restricts the color and alpha types that we support. If we
// swizzle ourselves, we can add support for:
// kUnpremul_SkAlphaType
// 16-bit per component RGBA
// kGray_8_SkColorType
// kIndex_8_SkColorType
// Additionally, it would be interesting to compare the performance
// of SkSwizzler with CG's built in swizzler.
if (!SkCopyPixelsFromCGImage(info, rowBytes, pixels, image)) {
return false;
return true;