Extract Image class so it can be used in more tests.
BUG=none
TEST=none (no functional change).
Review URL: http://codereview.chromium.org/149410
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@20491 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/printing/image.cc b/printing/image.cc
new file mode 100644
index 0000000..8f397d8
--- /dev/null
+++ b/printing/image.cc
@@ -0,0 +1,162 @@
+// Copyright (c) 2006-2009 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "printing/image.h"
+
+#include "base/file_util.h"
+#include "base/gfx/png_decoder.h"
+#include "base/gfx/png_encoder.h"
+#include "base/gfx/rect.h"
+#include "base/string_util.h"
+#include "printing/native_metafile.h"
+#include "skia/ext/platform_device.h"
+
+#if defined(OS_WIN)
+#include "base/gfx/gdi_util.h" // EMF support
+#endif
+
+printing::Image::Image(const std::wstring& filename) : ignore_alpha_(true) {
+ std::string data;
+ file_util::ReadFileToString(filename, &data);
+ std::wstring ext = file_util::GetFileExtensionFromPath(filename);
+ bool success = false;
+ if (LowerCaseEqualsASCII(ext, "png")) {
+ success = LoadPng(data);
+ } else if (LowerCaseEqualsASCII(ext, "emf")) {
+ success = LoadMetafile(data);
+ } else {
+ DCHECK(false);
+ }
+ if (!success) {
+ size_.SetSize(0, 0);
+ row_length_ = 0;
+ data_.clear();
+ }
+}
+
+bool printing::Image::SaveToPng(const std::wstring& filename) {
+ DCHECK(!data_.empty());
+ std::vector<unsigned char> compressed;
+ bool success = PNGEncoder::Encode(&*data_.begin(),
+ PNGEncoder::FORMAT_BGRA,
+ size_.width(),
+ size_.height(),
+ row_length_,
+ true,
+ &compressed);
+ DCHECK(success && compressed.size());
+ if (success) {
+ int write_bytes = file_util::WriteFile(
+ filename,
+ reinterpret_cast<char*>(&*compressed.begin()), compressed.size());
+ success = (write_bytes == static_cast<int>(compressed.size()));
+ DCHECK(success);
+ }
+ return success;
+}
+
+double printing::Image::PercentageDifferent(const Image& rhs) const {
+ if (size_.width() == 0 || size_.height() == 0 ||
+ rhs.size_.width() == 0 || rhs.size_.height() == 0)
+ return 100.;
+
+ int width = std::min(size_.width(), rhs.size_.width());
+ int height = std::min(size_.height(), rhs.size_.height());
+ // Compute pixels different in the overlap
+ int pixels_different = 0;
+ for (int y = 0; y < height; ++y) {
+ for (int x = 0; x < width; ++x) {
+ uint32 lhs_pixel = pixel_at(x, y);
+ uint32 rhs_pixel = rhs.pixel_at(x, y);
+ if (lhs_pixel != rhs_pixel)
+ ++pixels_different;
+ }
+
+ // Look for extra right lhs pixels. They should be white.
+ for (int x = width; x < size_.width(); ++x) {
+ uint32 lhs_pixel = pixel_at(x, y);
+ if (lhs_pixel != Color(SK_ColorWHITE))
+ ++pixels_different;
+ }
+
+ // Look for extra right rhs pixels. They should be white.
+ for (int x = width; x < rhs.size_.width(); ++x) {
+ uint32 rhs_pixel = rhs.pixel_at(x, y);
+ if (rhs_pixel != Color(SK_ColorWHITE))
+ ++pixels_different;
+ }
+ }
+
+ // Look for extra bottom lhs pixels. They should be white.
+ for (int y = height; y < size_.height(); ++y) {
+ for (int x = 0; x < size_.width(); ++x) {
+ uint32 lhs_pixel = pixel_at(x, y);
+ if (lhs_pixel != Color(SK_ColorWHITE))
+ ++pixels_different;
+ }
+ }
+
+ // Look for extra bottom rhs pixels. They should be white.
+ for (int y = height; y < rhs.size_.height(); ++y) {
+ for (int x = 0; x < rhs.size_.width(); ++x) {
+ uint32 rhs_pixel = rhs.pixel_at(x, y);
+ if (rhs_pixel != Color(SK_ColorWHITE))
+ ++pixels_different;
+ }
+ }
+
+ // Like the WebKit ImageDiff tool, we define percentage different in terms
+ // of the size of the 'actual' bitmap.
+ double total_pixels = static_cast<double>(size_.width()) *
+ static_cast<double>(height);
+ return static_cast<double>(pixels_different) / total_pixels * 100.;
+}
+
+bool printing::Image::LoadPng(const std::string& compressed) {
+ int w;
+ int h;
+ bool success = PNGDecoder::Decode(
+ reinterpret_cast<const unsigned char*>(compressed.c_str()),
+ compressed.size(), PNGDecoder::FORMAT_BGRA, &data_, &w, &h);
+ size_.SetSize(w, h);
+ row_length_ = size_.width() * sizeof(uint32);
+ return success;
+}
+
+bool printing::Image::LoadMetafile(const std::string& data) {
+ DCHECK(!data.empty());
+#if defined(OS_WIN)
+ printing::NativeMetafile metafile;
+ metafile.CreateFromData(data.data(), data.size());
+ gfx::Rect rect(metafile.GetBounds());
+ // Create a temporary HDC and bitmap to retrieve the rendered data.
+ HDC hdc = CreateCompatibleDC(NULL);
+ BITMAPV4HEADER hdr;
+ DCHECK_EQ(rect.x(), 0);
+ DCHECK_EQ(rect.y(), 0);
+ DCHECK_GT(rect.width(), 0);
+ DCHECK_GT(rect.height(), 0);
+ size_ = rect.size();
+ gfx::CreateBitmapV4Header(rect.width(), rect.height(), &hdr);
+ void* bits;
+ HBITMAP bitmap = CreateDIBSection(hdc,
+ reinterpret_cast<BITMAPINFO*>(&hdr), 0,
+ &bits, NULL, 0);
+ DCHECK(bitmap);
+ DCHECK(SelectObject(hdc, bitmap));
+ skia::PlatformDevice::InitializeDC(hdc);
+ bool success = metafile.Playback(hdc, NULL);
+ row_length_ = size_.width() * sizeof(uint32);
+ size_t bytes = row_length_ * size_.height();
+ DCHECK(bytes);
+ data_.resize(bytes);
+ memcpy(&*data_.begin(), bits, bytes);
+ DeleteDC(hdc);
+ DeleteObject(bitmap);
+ return success;
+#else
+ NOTIMPLEMENTED();
+ return false;
+#endif
+}
diff --git a/printing/image.h b/printing/image.h
new file mode 100644
index 0000000..8ef1007
--- /dev/null
+++ b/printing/image.h
@@ -0,0 +1,75 @@
+// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef PRINTING_IMAGE_H_
+#define PRINTING_IMAGE_H_
+
+#include <string>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/gfx/size.h"
+#include "base/logging.h"
+
+namespace printing {
+
+// Lightweight raw-bitmap management. The image, once initialized, is immuable.
+// The main purpose is testing image contents.
+class Image {
+ public:
+ // Creates the image from the given filename on disk. Uses extension to
+ // defer file type. PNG and EMF (on Windows) currently supported.
+ // If image loading fails size().IsEmpty() will be true.
+ explicit Image(const std::wstring& filename);
+
+ const gfx::Size& size() const {
+ return size_;
+ }
+
+ // Save image as PNG.
+ bool SaveToPng(const std::wstring& filename);
+
+ // Returns % of pixels different
+ double PercentageDifferent(const Image& rhs) const;
+
+ // Returns the 0x0RGB or 0xARGB value of the pixel at the given location.
+ uint32 Color(uint32 color) const {
+ if (ignore_alpha_)
+ return color & 0xFFFFFF; // Strip out A.
+ else
+ return color;
+ }
+
+ uint32 pixel_at(int x, int y) const {
+ DCHECK(x >= 0 && x < size_.width());
+ DCHECK(y >= 0 && y < size_.height());
+ const uint32* data = reinterpret_cast<const uint32*>(&*data_.begin());
+ const uint32* data_row = data + y * row_length_ / sizeof(uint32);
+ return Color(data_row[x]);
+ }
+
+ private:
+ bool LoadPng(const std::string& compressed);
+
+ bool LoadMetafile(const std::string& data);
+
+ // Pixel dimensions of the image.
+ gfx::Size size_;
+
+ // Length of a line in bytes.
+ int row_length_;
+
+ // Actual bitmap data in arrays of RGBAs (so when loaded as uint32, it's
+ // 0xABGR).
+ std::vector<unsigned char> data_;
+
+ // Flag to signal if the comparison functions should ignore the alpha channel.
+ const bool ignore_alpha_; // Currently always true.
+
+ DISALLOW_EVIL_CONSTRUCTORS(Image);
+};
+
+} // namespace printing
+
+#endif // PRINTING_IMAGE_H_
diff --git a/printing/printing.gyp b/printing/printing.gyp
index 8dd7a59..e199de85 100644
--- a/printing/printing.gyp
+++ b/printing/printing.gyp
@@ -29,6 +29,8 @@
'sources': [
'emf_win.cc',
'emf_win.h',
+ 'image.cc',
+ 'image.h',
'native_metafile.h',
'page_number.cc',
'page_number.h',