コード例 #1
0
static String CGImageToDataURL(CGImageRef image, const String& mimeType, const double* quality)
{
    RetainPtr<CFMutableDataRef> data(AdoptCF, CFDataCreateMutable(kCFAllocatorDefault, 0));
    if (!data)
        return "data:,";

    RetainPtr<CFStringRef> uti = utiFromMIMEType(mimeType);
    ASSERT(uti);

    RetainPtr<CGImageDestinationRef> destination(AdoptCF, CGImageDestinationCreateWithData(data.get(), uti.get(), 1, 0));
    if (!destination)
        return "data:,";

    RetainPtr<CFDictionaryRef> imageProperties = 0;
    if (CFEqual(uti.get(), jpegUTI()) && quality && *quality >= 0.0 && *quality <= 1.0) {
        // Apply the compression quality to the image destination.
        RetainPtr<CFNumberRef> compressionQuality(AdoptCF, CFNumberCreate(kCFAllocatorDefault, kCFNumberDoubleType, quality));
        const void* key = kCGImageDestinationLossyCompressionQuality;
        const void* value = compressionQuality.get();
        imageProperties.adoptCF(CFDictionaryCreate(0, &key, &value, 1, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks));
    }

    // Setting kCGImageDestinationBackgroundColor to black in imageProperties would allow saving some math in the
    // calling functions, but it doesn't seem to work.

    CGImageDestinationAddImage(destination.get(), image, imageProperties.get());
    CGImageDestinationFinalize(destination.get());

    Vector<char> out;
    base64Encode(reinterpret_cast<const char*>(CFDataGetBytePtr(data.get())), CFDataGetLength(data.get()), out);

    return "data:" + mimeType + ";base64," + out;
}
コード例 #2
0
String ImageBuffer::toDataURL(const String& mimeType, const double* quality) const
{
    ASSERT(MIMETypeRegistry::isSupportedImageMIMETypeForEncoding(mimeType));

    RetainPtr<CGImageRef> image;
    if (!m_accelerateRendering)
        image.adoptCF(CGBitmapContextCreateImage(context()->platformContext()));
#if USE(IOSURFACE_CANVAS_BACKING_STORE)
    else
        image.adoptCF(wkIOSurfaceContextCreateImage(context()->platformContext()));
#endif

    if (!image)
        return "data:,";

    RetainPtr<CFMutableDataRef> data(AdoptCF, CFDataCreateMutable(kCFAllocatorDefault, 0));
    if (!data)
        return "data:,";

    RetainPtr<CFStringRef> uti = utiFromMIMEType(mimeType);
    ASSERT(uti);

    RetainPtr<CGImageDestinationRef> destination(AdoptCF, CGImageDestinationCreateWithData(data.get(), uti.get(), 1, 0));
    if (!destination)
        return "data:,";

    RetainPtr<CFDictionaryRef> imageProperties = 0;
    if (CFEqual(uti.get(), jpegUTI()) && quality && *quality >= 0.0 && *quality <= 1.0) {
        // Apply the compression quality to the image destination.
        RetainPtr<CFNumberRef> compressionQuality(AdoptCF, CFNumberCreate(kCFAllocatorDefault, kCFNumberDoubleType, quality));
        const void* key = kCGImageDestinationLossyCompressionQuality;
        const void* value = compressionQuality.get();
        imageProperties.adoptCF(CFDictionaryCreate(0, &key, &value, 1, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks));
    }

    CGImageDestinationAddImage(destination.get(), image.get(), imageProperties.get());
    CGImageDestinationFinalize(destination.get());

    Vector<char> out;
    base64Encode(reinterpret_cast<const char*>(CFDataGetBytePtr(data.get())), CFDataGetLength(data.get()), out);

    return makeString("data:", mimeType, ";base64,", out);
}