commit 698315531414b223b35d8507fdf2f56dbcf6bc4c
author Tomaž Vajngerl <quikee@gmail.com> Sun Jul 28 15:52:14 2013 +0200
committer Tomaž Vajngerl <quikee@gmail.com> Sun Jul 28 16:06:44 2013 +0200
tree 717ddfd96bc310979b380cb894990a8be93886d4
parent b5e3929a35965f32638a80c3627b98f4fa306875

fdo#66006 Convert to PNG for JPEG that can't be losslessly rotated

If a JPEG image has a width or height which is not a multiple of 16
(width/heigh % 16 != 0) then it can't be completelly lossleessly
rotated (the last uncomplete MCUs can't be rotated) and the image
is cropped on the lower size. To prevent this such JPEG images
must be rotated to PNG to prevent loss. Afterwards image can still
be compressed with "Compress Graphic Dialog".

Change-Id: Ie2803512a93bba55573bf66c547f132f37cba711

vcl/source/filter/GraphicNativeTransform.cxx

diff --git a/vcl/source/filter/GraphicNativeTransform.cxx b/vcl/source/filter/GraphicNativeTransform.cxx
index 261ad90..69a10bd 100644
--- a/vcl/source/filter/GraphicNativeTransform.cxx
+++ b/vcl/source/filter/GraphicNativeTransform.cxx
@@ -141,45 +141,50 @@ bool GraphicNativeTransform::rotateGeneric(sal_uInt16 aRotation, OUString aType)

bool GraphicNativeTransform::rotateJPEG(sal_uInt16 aRotation)
{
    GfxLink aLink = mrGraphic.GetLink();

    SvMemoryStream aSourceStream;
    aSourceStream.Write(aLink.GetData(), aLink.GetDataSize());
    aSourceStream.Seek( STREAM_SEEK_TO_BEGIN );

    Orientation aOrientation = TOP_LEFT;

    Exif exif;
    if ( exif.read(aSourceStream) )
    {
        aOrientation = exif.getOrientation();
    }

    SvMemoryStream aTargetStream;
    JpegTransform tranform(aSourceStream, aTargetStream);
    tranform.setRotate(aRotation);
    tranform.perform();

    aTargetStream.Seek( STREAM_SEEK_TO_BEGIN );

    // Reset orientation in exif if needed
    if ( exif.hasExif() && aOrientation != TOP_LEFT)
    {
        exif.setOrientation(TOP_LEFT);
        exif.write(aTargetStream);
    }

    aTargetStream.Seek( STREAM_SEEK_TO_END );
    sal_uInt32 aBufferSize = aTargetStream.Tell();
    sal_uInt8* pBuffer = new sal_uInt8[ aBufferSize ];

    aTargetStream.Seek( STREAM_SEEK_TO_BEGIN );
    aTargetStream.Read( pBuffer, aBufferSize );

    BitmapEx aBitmap = mrGraphic.GetBitmapEx();
    aBitmap.Rotate(aRotation, COL_BLACK);
    mrGraphic = aBitmap;
    mrGraphic.SetLink( GfxLink( pBuffer, aBufferSize, aLink.GetType(), sal_True ) );

    if (aBitmap.GetSizePixel().Width()  % 16 != 0 ||
        aBitmap.GetSizePixel().Height() % 16 != 0 )
    {
        rotateGeneric(aRotation, OUString("png"));
    }
    else
    {
        GfxLink aLink = mrGraphic.GetLink();

        SvMemoryStream aSourceStream;
        aSourceStream.Write(aLink.GetData(), aLink.GetDataSize());
        aSourceStream.Seek( STREAM_SEEK_TO_BEGIN );

        Orientation aOrientation = TOP_LEFT;

        Exif exif;
        if ( exif.read(aSourceStream) )
        {
            aOrientation = exif.getOrientation();
        }

        SvMemoryStream aTargetStream;
        JpegTransform tranform(aSourceStream, aTargetStream);
        tranform.setRotate(aRotation);
        tranform.perform();

        aTargetStream.Seek( STREAM_SEEK_TO_BEGIN );

        // Reset orientation in exif if needed
        if ( exif.hasExif() && aOrientation != TOP_LEFT)
        {
            exif.setOrientation(TOP_LEFT);
            exif.write(aTargetStream);
        }

        aTargetStream.Seek( STREAM_SEEK_TO_BEGIN );

        Graphic aGraphic;
        GraphicFilter& rFilter = GraphicFilter::GetGraphicFilter();
        rFilter.ImportGraphic( aGraphic, OUString("import"), aTargetStream );
        mrGraphic = aGraphic;
    }

    return true;
}