ui/gfx/image/image_mac.mm

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "ui/gfx/image/image.h"
   6
   7 #import <AppKit/AppKit.h>
   8
   9 #include "base/logging.h"
  10 #include "base/mac/scoped_nsobject.h"
  11 #include "ui/gfx/geometry/size.h"
  12 #include "ui/gfx/image/image_png_rep.h"
  13
  14 namespace gfx {
  15 namespace internal {
  16
  17 namespace {
  18
  19 // Returns a 16x16 red NSImage to visually show when a NSImage cannot be
  20 // created from PNG data.
  21 // Caller takes ownership of the returned NSImage.
  22 NSImage* GetErrorNSImage() {
  23   NSRect rect = NSMakeRect(0, 0, 16, 16);
  24   NSImage* image = [[NSImage alloc] initWithSize:rect.size];
  25   [image lockFocus];
  26   [[NSColor colorWithDeviceRed:1.0 green:0.0 blue:0.0 alpha:1.0] set];
  27   NSRectFill(rect);
  28   [image unlockFocus];
  29   return image;
  30 }
  31
  32 }  // namespace
  33
  34 scoped_refptr<base::RefCountedMemory> Get1xPNGBytesFromNSImage(
  35     NSImage* nsimage) {
  36   CGImageRef cg_image = [nsimage CGImageForProposedRect:NULL
  37                                                 context:nil
  38                                                   hints:nil];
  39   base::scoped_nsobject<NSBitmapImageRep> ns_bitmap(
  40       [[NSBitmapImageRep alloc] initWithCGImage:cg_image]);
  41   NSData* ns_data = [ns_bitmap representationUsingType:NSPNGFileType
  42                                             properties:@{}];
  43   const unsigned char* bytes =
  44       static_cast<const unsigned char*>([ns_data bytes]);
  45   scoped_refptr<base::RefCountedBytes> refcounted_bytes(
  46       new base::RefCountedBytes());
  47   refcounted_bytes->data().assign(bytes, bytes + [ns_data length]);
  48   return refcounted_bytes;
  49 }
  50
  51 NSImage* NSImageFromPNG(const std::vector<gfx::ImagePNGRep>& image_png_reps,
  52                         CGColorSpaceRef color_space) {
  53   if (image_png_reps.empty()) {
  54     LOG(ERROR) << "Unable to decode PNG.";
  55     return GetErrorNSImage();
  56   }
  57
  58   base::scoped_nsobject<NSImage> image;
  59   for (size_t i = 0; i < image_png_reps.size(); ++i) {
  60     scoped_refptr<base::RefCountedMemory> png = image_png_reps[i].raw_data;
  61     CHECK(png.get());
  62     base::scoped_nsobject<NSData> ns_data(
  63         [[NSData alloc] initWithBytes:png->front() length:png->size()]);
  64     base::scoped_nsobject<NSBitmapImageRep> ns_image_rep(
  65         [[NSBitmapImageRep alloc] initWithData:ns_data]);
  66     if (!ns_image_rep) {
  67       LOG(ERROR) << "Unable to decode PNG at "
  68                  << image_png_reps[i].scale
  69                  << ".";
  70       return GetErrorNSImage();
  71     }
  72
  73     // PNGCodec ignores colorspace related ancillary chunks (sRGB, iCCP). Ignore
  74     // colorspace information when decoding directly from PNG to an NSImage so
  75     // that the conversions: PNG -> SkBitmap -> NSImage and PNG -> NSImage
  76     // produce visually similar results.
  77     CGColorSpaceModel decoded_color_space_model = CGColorSpaceGetModel(
  78         [[ns_image_rep colorSpace] CGColorSpace]);
  79     CGColorSpaceModel color_space_model = CGColorSpaceGetModel(color_space);
  80     if (decoded_color_space_model == color_space_model) {
  81       base::scoped_nsobject<NSColorSpace> ns_color_space(
  82           [[NSColorSpace alloc] initWithCGColorSpace:color_space]);
  83       NSBitmapImageRep* ns_retagged_image_rep =
  84           [ns_image_rep
  85               bitmapImageRepByRetaggingWithColorSpace:ns_color_space];
  86       if (ns_retagged_image_rep && ns_retagged_image_rep != ns_image_rep)
  87         ns_image_rep.reset([ns_retagged_image_rep retain]);
  88     }
  89
  90     if (!image.get()) {
  91       float scale = image_png_reps[i].scale;
  92       NSSize image_size = NSMakeSize([ns_image_rep pixelsWide] / scale,
  93                                      [ns_image_rep pixelsHigh] / scale);
  94       image.reset([[NSImage alloc] initWithSize:image_size]);
  95     }
  96     [image addRepresentation:ns_image_rep];
  97   }
  98
  99   return image.release();
 100 }
 101
 102 gfx::Size NSImageSize(NSImage* image) {
 103   NSSize size = [image size];
 104   int width = static_cast<int>(size.width);
 105   int height = static_cast<int>(size.height);
 106   return gfx::Size(width, height);
 107 }
 108
 109 } // namespace internal
 110 } // namespace gfx
 111