1 // Copyright (c) 2011 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 "printing/image.h" 6 7 #include <algorithm> 8 9 #include "base/file_util.h" 10 #include "base/md5.h" 11 #include "base/safe_numerics.h" 12 #include "base/strings/string_number_conversions.h" 13 #include "printing/metafile.h" 14 #include "printing/metafile_impl.h" 15 #include "third_party/skia/include/core/SkColor.h" 16 #include "ui/gfx/codec/png_codec.h" 17 18 namespace printing { 19 20 Image::Image(const base::FilePath& path) 21 : row_length_(0), 22 ignore_alpha_(true) { 23 std::string data; 24 base::ReadFileToString(path, &data); 25 bool success = false; 26 if (path.MatchesExtension(FILE_PATH_LITERAL(".png"))) { 27 success = LoadPng(data); 28 } else if (path.MatchesExtension(FILE_PATH_LITERAL(".emf"))) { 29 success = LoadMetafile(data); 30 } else { 31 DCHECK(false); 32 } 33 if (!success) { 34 size_.SetSize(0, 0); 35 row_length_ = 0; 36 data_.clear(); 37 } 38 } 39 40 Image::Image(const Metafile& metafile) 41 : row_length_(0), 42 ignore_alpha_(true) { 43 LoadMetafile(metafile); 44 } 45 46 Image::Image(const Image& image) 47 : size_(image.size_), 48 row_length_(image.row_length_), 49 data_(image.data_), 50 ignore_alpha_(image.ignore_alpha_) { 51 } 52 53 Image::~Image() {} 54 55 std::string Image::checksum() const { 56 base::MD5Digest digest; 57 base::MD5Sum(&data_[0], data_.size(), &digest); 58 return base::HexEncode(&digest, sizeof(digest)); 59 } 60 61 bool Image::SaveToPng(const base::FilePath& filepath) const { 62 DCHECK(!data_.empty()); 63 std::vector<unsigned char> compressed; 64 bool success = gfx::PNGCodec::Encode(&*data_.begin(), 65 gfx::PNGCodec::FORMAT_BGRA, 66 size_, 67 row_length_, 68 true, 69 std::vector<gfx::PNGCodec::Comment>(), 70 &compressed); 71 DCHECK(success && compressed.size()); 72 if (success) { 73 int write_bytes = file_util::WriteFile( 74 filepath, 75 reinterpret_cast<char*>(&*compressed.begin()), 76 base::checked_numeric_cast<int>(compressed.size())); 77 success = (write_bytes == static_cast<int>(compressed.size())); 78 DCHECK(success); 79 } 80 return success; 81 } 82 83 double Image::PercentageDifferent(const Image& rhs) const { 84 if (size_.width() == 0 || size_.height() == 0 || 85 rhs.size_.width() == 0 || rhs.size_.height() == 0) 86 return 100.; 87 88 int width = std::min(size_.width(), rhs.size_.width()); 89 int height = std::min(size_.height(), rhs.size_.height()); 90 // Compute pixels different in the overlap 91 int pixels_different = 0; 92 for (int y = 0; y < height; ++y) { 93 for (int x = 0; x < width; ++x) { 94 uint32 lhs_pixel = pixel_at(x, y); 95 uint32 rhs_pixel = rhs.pixel_at(x, y); 96 if (lhs_pixel != rhs_pixel) 97 ++pixels_different; 98 } 99 100 // Look for extra right lhs pixels. They should be white. 101 for (int x = width; x < size_.width(); ++x) { 102 uint32 lhs_pixel = pixel_at(x, y); 103 if (lhs_pixel != Color(SK_ColorWHITE)) 104 ++pixels_different; 105 } 106 107 // Look for extra right rhs pixels. They should be white. 108 for (int x = width; x < rhs.size_.width(); ++x) { 109 uint32 rhs_pixel = rhs.pixel_at(x, y); 110 if (rhs_pixel != Color(SK_ColorWHITE)) 111 ++pixels_different; 112 } 113 } 114 115 // Look for extra bottom lhs pixels. They should be white. 116 for (int y = height; y < size_.height(); ++y) { 117 for (int x = 0; x < size_.width(); ++x) { 118 uint32 lhs_pixel = pixel_at(x, y); 119 if (lhs_pixel != Color(SK_ColorWHITE)) 120 ++pixels_different; 121 } 122 } 123 124 // Look for extra bottom rhs pixels. They should be white. 125 for (int y = height; y < rhs.size_.height(); ++y) { 126 for (int x = 0; x < rhs.size_.width(); ++x) { 127 uint32 rhs_pixel = rhs.pixel_at(x, y); 128 if (rhs_pixel != Color(SK_ColorWHITE)) 129 ++pixels_different; 130 } 131 } 132 133 // Like the WebKit ImageDiff tool, we define percentage different in terms 134 // of the size of the 'actual' bitmap. 135 double total_pixels = static_cast<double>(size_.width()) * 136 static_cast<double>(height); 137 return static_cast<double>(pixels_different) / total_pixels * 100.; 138 } 139 140 bool Image::LoadPng(const std::string& compressed) { 141 int w; 142 int h; 143 bool success = gfx::PNGCodec::Decode( 144 reinterpret_cast<const unsigned char*>(compressed.c_str()), 145 compressed.size(), gfx::PNGCodec::FORMAT_BGRA, &data_, &w, &h); 146 size_.SetSize(w, h); 147 row_length_ = size_.width() * sizeof(uint32); 148 return success; 149 } 150 151 bool Image::LoadMetafile(const std::string& data) { 152 DCHECK(!data.empty()); 153 NativeMetafile metafile; 154 if (!metafile.InitFromData(data.data(), 155 base::checked_numeric_cast<uint32>(data.size()))) 156 return false; 157 return LoadMetafile(metafile); 158 } 159 160 } // namespace printing 161
