The Tor Browser: widget/gtk/nsImageToPixbuf.cpp@6474c204b198

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

     1 /* vim:set sw=4 sts=4 et cin: */

     2 /* This Source Code Form is subject to the terms of the Mozilla Public

     3  * License, v. 2.0. If a copy of the MPL was not distributed with this

     4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

     6 #include <gdk-pixbuf/gdk-pixbuf.h>

     8 #include "nsImageToPixbuf.h"

    10 #include "imgIContainer.h"

    11 #include "mozilla/gfx/2D.h"

    12 #include "mozilla/RefPtr.h"

    13 #include "nsAutoPtr.h"

    15 using mozilla::gfx::DataSourceSurface;

    16 using mozilla::gfx::SurfaceFormat;

    17 using mozilla::RefPtr;

    19 NS_IMPL_ISUPPORTS(nsImageToPixbuf, nsIImageToPixbuf)

    21 inline unsigned char

    22 unpremultiply (unsigned char color,

    23                unsigned char alpha)

    24 {

    25     if (alpha == 0)

    26         return 0;

    27     // plus alpha/2 to round instead of truncate

    28     return (color * 255 + alpha / 2) / alpha;

    29 }

    31 NS_IMETHODIMP_(GdkPixbuf*)

    32 nsImageToPixbuf::ConvertImageToPixbuf(imgIContainer* aImage)

    33 {

    34     return ImageToPixbuf(aImage);

    35 }

    37 GdkPixbuf*

    38 nsImageToPixbuf::ImageToPixbuf(imgIContainer* aImage)

    39 {

    40     RefPtr<SourceSurface> surface =

    41       aImage->GetFrame(imgIContainer::FRAME_CURRENT,

    42                        imgIContainer::FLAG_SYNC_DECODE);

    44     // If the last call failed, it was probably because our call stack originates

    45     // in an imgINotificationObserver event, meaning that we're not allowed request

    46     // a sync decode. Presumably the originating event is something sensible like

    47     // OnStopFrame(), so we can just retry the call without a sync decode.

    48     if (!surface)

    49       surface = aImage->GetFrame(imgIContainer::FRAME_CURRENT,

    50                                  imgIContainer::FLAG_NONE);

    52     NS_ENSURE_TRUE(surface, nullptr);

    54     return SourceSurfaceToPixbuf(surface,

    55                                  surface->GetSize().width,

    56                                  surface->GetSize().height);

    57 }

    59 GdkPixbuf*

    60 nsImageToPixbuf::SourceSurfaceToPixbuf(SourceSurface* aSurface,

    61                                        int32_t aWidth,

    62                                        int32_t aHeight)

    63 {

    64     MOZ_ASSERT(aWidth <= aSurface->GetSize().width &&

    65                aHeight <= aSurface->GetSize().height,

    66                "Requested rect is bigger than the supplied surface");

    68     GdkPixbuf* pixbuf = gdk_pixbuf_new(GDK_COLORSPACE_RGB, TRUE, 8,

    69                                        aWidth, aHeight);

    70     if (!pixbuf)

    71         return nullptr;

    73     uint32_t destStride = gdk_pixbuf_get_rowstride (pixbuf);

    74     guchar* destPixels = gdk_pixbuf_get_pixels (pixbuf);

    76     RefPtr<DataSourceSurface> dataSurface = aSurface->GetDataSurface();

    77     DataSourceSurface::MappedSurface map;

    78     dataSurface->Map(DataSourceSurface::MapType::READ, &map);

    79     uint8_t* srcData = map.mData;

    80     int32_t srcStride = map.mStride;

    82     SurfaceFormat format = dataSurface->GetFormat();

    84     for (int32_t row = 0; row < aHeight; ++row) {

    85         for (int32_t col = 0; col < aWidth; ++col) {

    86             guchar* destPixel = destPixels + row * destStride + 4 * col;

    88             uint32_t* srcPixel =

    89                 reinterpret_cast<uint32_t*>((srcData + row * srcStride + 4 * col));

    91             if (format == SurfaceFormat::B8G8R8A8) {

    92                 const uint8_t a = (*srcPixel >> 24) & 0xFF;

    93                 const uint8_t r = unpremultiply((*srcPixel >> 16) & 0xFF, a);

    94                 const uint8_t g = unpremultiply((*srcPixel >>  8) & 0xFF, a);

    95                 const uint8_t b = unpremultiply((*srcPixel >>  0) & 0xFF, a);

    97                 *destPixel++ = r;

    98                 *destPixel++ = g;

    99                 *destPixel++ = b;

   100                 *destPixel++ = a;

   101             } else {

   102                 MOZ_ASSERT(format == SurfaceFormat::B8G8R8X8);

   104                 const uint8_t r = (*srcPixel >> 16) & 0xFF;

   105                 const uint8_t g = (*srcPixel >>  8) & 0xFF;

   106                 const uint8_t b = (*srcPixel >>  0) & 0xFF;

   108                 *destPixel++ = r;

   109                 *destPixel++ = g;

   110                 *destPixel++ = b;

   111                 *destPixel++ = 0xFF; // A

   112             }

   113         }

   114     }

   116     dataSurface->Unmap();

   118     return pixbuf;

   119 }

The Tor Browser / file revision