ChangeLog

112012-05-30 Allan Sandfeld Jensen <allan.jensen@nokia.com>

        [Qt] ImageDecoderQt doesn't support some decoders.

        https://bugs.webkit.org/show_bug.cgi?id=87851

        Reviewed by NOBODY (OOPS!).

        If forced to decode GIF and JPEG, ImageDecoderQt show several

        artifacts. This is caused by mismatched decoded image-formats.

        Convert mismatched color spaces into ARGB color space, and perform

        manual mem-copy when the image has been decoded into a new buffer.

        This patch also add support for down-scaling in the decoder.

        * platform/graphics/qt/ImageDecoderQt.cpp:

        (WebCore::ImageDecoderQt::internalDecodeSize):

        (WebCore::ImageDecoderQt::internalHandleCurrentImage):

2012-05-30  Allan Sandfeld Jensen  <allan.jensen@nokia.com>

        [Qt] Support IMAGE_DECODER_DOWN_SAMPLING flag.

        https://bugs.webkit.org/show_bug.cgi?id=87840

Source/WebCore/platform/graphics/qt/ImageDecoderQt.cpp

@@void ImageDecoderQt::internalDecodeSize()

    }

    setSize(size.width(), size.height());

    // We don't need the tables set by prepareScaleDataIfNecessary,

    // but their dimensions are used by ImageDecoder::scaledSize().

    prepareScaleDataIfNecessary();

    if (m_scaled)

        m_reader->setScaledSize(scaledSize());

}

void ImageDecoderQt::internalReadImage(size_t frameIndex)

@@void ImageDecoderQt::internalReadImage(size_t frameIndex)

bool ImageDecoderQt::internalHandleCurrentImage(size_t frameIndex)

{

    ImageFrame* const buffer = &m_frameBufferCache[frameIndex];

187 QSize imageSize = m_reader->size();

    QSize imageSize = m_reader->scaledSize();

    if (imageSize.isEmpty())

        imageSize = m_reader->size();

    if (!buffer->setSize(imageSize.width(), imageSize.height()))

        return false;

@@bool ImageDecoderQt::internalHandleCurrentImage(size_t frameIndex)

    buffer->setDuration(m_reader->nextImageDelay());

    m_reader->read(&image);

    // ImageFrame expects ARGB32.

    if (buffer->premultiplyAlpha()) {

        if (image.format() != QImage::Format_ARGB32_Premultiplied)

            image = image.convertToFormat(QImage::Format_ARGB32_Premultiplied);

    } else {

        if (image.format() != QImage::Format_ARGB32)

            image = image.convertToFormat(QImage::Format_ARGB32);

    }

    if (reinterpret_cast<const uchar*>(image.constBits()) != reinterpret_cast<const uchar*>(buffer->getAddr(0, 0))) {

        // The in-buffer was replaced during decoding with another, so copy into it manually.

        memcpy(buffer->getAddr(0, 0), image.constBits(),  image.byteCount());

    }

    if (image.isNull()) {

        frameCount();

        repetitionCount();