1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/widget/gtk/nsImageToPixbuf.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,120 @@
1.4 +/* vim:set sw=4 sts=4 et cin: */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#include <gdk-pixbuf/gdk-pixbuf.h>
1.10 +
1.11 +#include "nsImageToPixbuf.h"
1.12 +
1.13 +#include "imgIContainer.h"
1.14 +#include "mozilla/gfx/2D.h"
1.15 +#include "mozilla/RefPtr.h"
1.16 +#include "nsAutoPtr.h"
1.17 +
1.18 +using mozilla::gfx::DataSourceSurface;
1.19 +using mozilla::gfx::SurfaceFormat;
1.20 +using mozilla::RefPtr;
1.21 +
1.22 +NS_IMPL_ISUPPORTS(nsImageToPixbuf, nsIImageToPixbuf)
1.23 +
1.24 +inline unsigned char
1.25 +unpremultiply (unsigned char color,
1.26 + unsigned char alpha)
1.27 +{
1.28 + if (alpha == 0)
1.29 + return 0;
1.30 + // plus alpha/2 to round instead of truncate
1.31 + return (color * 255 + alpha / 2) / alpha;
1.32 +}
1.33 +
1.34 +NS_IMETHODIMP_(GdkPixbuf*)
1.35 +nsImageToPixbuf::ConvertImageToPixbuf(imgIContainer* aImage)
1.36 +{
1.37 + return ImageToPixbuf(aImage);
1.38 +}
1.39 +
1.40 +GdkPixbuf*
1.41 +nsImageToPixbuf::ImageToPixbuf(imgIContainer* aImage)
1.42 +{
1.43 + RefPtr<SourceSurface> surface =
1.44 + aImage->GetFrame(imgIContainer::FRAME_CURRENT,
1.45 + imgIContainer::FLAG_SYNC_DECODE);
1.46 +
1.47 + // If the last call failed, it was probably because our call stack originates
1.48 + // in an imgINotificationObserver event, meaning that we're not allowed request
1.49 + // a sync decode. Presumably the originating event is something sensible like
1.50 + // OnStopFrame(), so we can just retry the call without a sync decode.
1.51 + if (!surface)
1.52 + surface = aImage->GetFrame(imgIContainer::FRAME_CURRENT,
1.53 + imgIContainer::FLAG_NONE);
1.54 +
1.55 + NS_ENSURE_TRUE(surface, nullptr);
1.56 +
1.57 + return SourceSurfaceToPixbuf(surface,
1.58 + surface->GetSize().width,
1.59 + surface->GetSize().height);
1.60 +}
1.61 +
1.62 +GdkPixbuf*
1.63 +nsImageToPixbuf::SourceSurfaceToPixbuf(SourceSurface* aSurface,
1.64 + int32_t aWidth,
1.65 + int32_t aHeight)
1.66 +{
1.67 + MOZ_ASSERT(aWidth <= aSurface->GetSize().width &&
1.68 + aHeight <= aSurface->GetSize().height,
1.69 + "Requested rect is bigger than the supplied surface");
1.70 +
1.71 + GdkPixbuf* pixbuf = gdk_pixbuf_new(GDK_COLORSPACE_RGB, TRUE, 8,
1.72 + aWidth, aHeight);
1.73 + if (!pixbuf)
1.74 + return nullptr;
1.75 +
1.76 + uint32_t destStride = gdk_pixbuf_get_rowstride (pixbuf);
1.77 + guchar* destPixels = gdk_pixbuf_get_pixels (pixbuf);
1.78 +
1.79 + RefPtr<DataSourceSurface> dataSurface = aSurface->GetDataSurface();
1.80 + DataSourceSurface::MappedSurface map;
1.81 + dataSurface->Map(DataSourceSurface::MapType::READ, &map);
1.82 + uint8_t* srcData = map.mData;
1.83 + int32_t srcStride = map.mStride;
1.84 +
1.85 + SurfaceFormat format = dataSurface->GetFormat();
1.86 +
1.87 + for (int32_t row = 0; row < aHeight; ++row) {
1.88 + for (int32_t col = 0; col < aWidth; ++col) {
1.89 + guchar* destPixel = destPixels + row * destStride + 4 * col;
1.90 +
1.91 + uint32_t* srcPixel =
1.92 + reinterpret_cast<uint32_t*>((srcData + row * srcStride + 4 * col));
1.93 +
1.94 + if (format == SurfaceFormat::B8G8R8A8) {
1.95 + const uint8_t a = (*srcPixel >> 24) & 0xFF;
1.96 + const uint8_t r = unpremultiply((*srcPixel >> 16) & 0xFF, a);
1.97 + const uint8_t g = unpremultiply((*srcPixel >> 8) & 0xFF, a);
1.98 + const uint8_t b = unpremultiply((*srcPixel >> 0) & 0xFF, a);
1.99 +
1.100 + *destPixel++ = r;
1.101 + *destPixel++ = g;
1.102 + *destPixel++ = b;
1.103 + *destPixel++ = a;
1.104 + } else {
1.105 + MOZ_ASSERT(format == SurfaceFormat::B8G8R8X8);
1.106 +
1.107 + const uint8_t r = (*srcPixel >> 16) & 0xFF;
1.108 + const uint8_t g = (*srcPixel >> 8) & 0xFF;
1.109 + const uint8_t b = (*srcPixel >> 0) & 0xFF;
1.110 +
1.111 + *destPixel++ = r;
1.112 + *destPixel++ = g;
1.113 + *destPixel++ = b;
1.114 + *destPixel++ = 0xFF; // A
1.115 + }
1.116 + }
1.117 + }
1.118 +
1.119 + dataSurface->Unmap();
1.120 +
1.121 + return pixbuf;
1.122 +}
1.123 +
