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/*
* Copyright (C) 2010 Igalia S.L.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "config.h"
#include "ImageBuffer.h"
#include "CairoUtilities.h"
#include "GdkCairoUtilities.h"
#include "GRefPtrGtk.h"
#include "MIMETypeRegistry.h"
#include <cairo.h>
#include <gtk/gtk.h>
#include <wtf/glib/GUniquePtr.h>
#include <wtf/text/Base64.h>
#include <wtf/text/CString.h>
#include <wtf/text/WTFString.h>
namespace WebCore {
static bool encodeImage(cairo_surface_t* surface, const String& mimeType, std::optional<double> quality, GUniqueOutPtr<gchar>& buffer, gsize& bufferSize)
{
// List of supported image encoding types comes from the GdkPixbuf documentation.
// http://developer.gnome.org/gdk-pixbuf/stable/gdk-pixbuf-File-saving.html#gdk-pixbuf-save-to-bufferv
String type = mimeType.substring(sizeof "image");
if (type != "jpeg" && type != "png" && type != "tiff" && type != "ico" && type != "bmp")
return false;
GRefPtr<GdkPixbuf> pixbuf;
if (type == "jpeg") {
// JPEG doesn't support alpha channel. The <canvas> spec states that toDataURL() must encode a Porter-Duff
// composite source-over black for image types that do not support alpha.
RefPtr<cairo_surface_t> newSurface;
if (cairo_surface_get_type(surface) == CAIRO_SURFACE_TYPE_IMAGE) {
newSurface = adoptRef(cairo_image_surface_create_for_data(cairo_image_surface_get_data(surface),
CAIRO_FORMAT_RGB24,
cairo_image_surface_get_width(surface),
cairo_image_surface_get_height(surface),
cairo_image_surface_get_stride(surface)));
} else {
IntSize size = cairoSurfaceSize(surface);
newSurface = adoptRef(cairo_image_surface_create(CAIRO_FORMAT_RGB24, size.width(), size.height()));
RefPtr<cairo_t> cr = adoptRef(cairo_create(newSurface.get()));
cairo_set_source_surface(cr.get(), surface, 0, 0);
cairo_paint(cr.get());
}
pixbuf = adoptGRef(cairoSurfaceToGdkPixbuf(newSurface.get()));
} else
pixbuf = adoptGRef(cairoSurfaceToGdkPixbuf(surface));
if (!pixbuf)
return false;
GUniqueOutPtr<GError> error;
if (type == "jpeg" && quality && *quality >= 0.0 && *quality <= 1.0) {
String qualityString = String::format("%d", static_cast<int>(*quality * 100.0 + 0.5));
gdk_pixbuf_save_to_buffer(pixbuf.get(), &buffer.outPtr(), &bufferSize, type.utf8().data(), &error.outPtr(), "quality", qualityString.utf8().data(), NULL);
} else
gdk_pixbuf_save_to_buffer(pixbuf.get(), &buffer.outPtr(), &bufferSize, type.utf8().data(), &error.outPtr(), NULL);
return !error;
}
String ImageBuffer::toDataURL(const String& mimeType, std::optional<double> quality, PreserveResolution) const
{
Vector<uint8_t> imageData = toData(mimeType, quality);
if (imageData.isEmpty())
return "data:,";
Vector<char> base64Data;
base64Encode(imageData.data(), imageData.size(), base64Data);
return "data:" + mimeType + ";base64," + base64Data;
}
Vector<uint8_t> ImageBuffer::toData(const String& mimeType, std::optional<double> quality) const
{
ASSERT(MIMETypeRegistry::isSupportedImageMIMETypeForEncoding(mimeType));
GUniqueOutPtr<gchar> buffer;
gsize bufferSize;
if (!encodeImage(m_data.m_surface.get(), mimeType, quality, buffer, bufferSize))
return { };
Vector<uint8_t> imageData;
imageData.append(buffer.get(), bufferSize);
return imageData;
}
}