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diff --git a/chromium/ui/gfx/codec/png_codec.h b/chromium/ui/gfx/codec/png_codec.h
new file mode 100644
index 00000000000..3a6d295dbdf
--- /dev/null
+++ b/chromium/ui/gfx/codec/png_codec.h
@@ -0,0 +1,134 @@
+// Copyright (c) 2011 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 UI_GFX_CODEC_PNG_CODEC_H_
+#define UI_GFX_CODEC_PNG_CODEC_H_
+
+#include <string>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "ui/base/ui_export.h"
+
+class SkBitmap;
+
+namespace gfx {
+
+class Size;
+
+// Interface for encoding and decoding PNG data. This is a wrapper around
+// libpng, which has an inconvenient interface for callers. This is currently
+// designed for use in tests only (where we control the files), so the handling
+// isn't as robust as would be required for a browser (see Decode() for more).
+// WebKit has its own more complicated PNG decoder which handles, among other
+// things, partially downloaded data.
+class UI_EXPORT PNGCodec {
+ public:
+  enum ColorFormat {
+    // 3 bytes per pixel (packed), in RGB order regardless of endianness.
+    // This is the native JPEG format.
+    FORMAT_RGB,
+
+    // 4 bytes per pixel, in RGBA order in memory regardless of endianness.
+    FORMAT_RGBA,
+
+    // 4 bytes per pixel, in BGRA order in memory regardless of endianness.
+    // This is the default Windows DIB order.
+    FORMAT_BGRA,
+
+    // 4 bytes per pixel, in pre-multiplied kARGB_8888_Config format. For use
+    // with directly writing to a skia bitmap.
+    FORMAT_SkBitmap
+  };
+
+  // Represents a comment in the tEXt ancillary chunk of the png.
+  struct UI_EXPORT Comment {
+    Comment(const std::string& k, const std::string& t);
+    ~Comment();
+
+    std::string key;
+    std::string text;
+  };
+
+  // Calls PNGCodec::EncodeWithCompressionLevel with the default compression
+  // level.
+  static bool Encode(const unsigned char* input,
+                     ColorFormat format,
+                     const Size& size,
+                     int row_byte_width,
+                     bool discard_transparency,
+                     const std::vector<Comment>& comments,
+                     std::vector<unsigned char>* output);
+
+  // Encodes the given raw 'input' data, with each pixel being represented as
+  // given in 'format'. The encoded PNG data will be written into the supplied
+  // vector and true will be returned on success. On failure (false), the
+  // contents of the output buffer are undefined.
+  //
+  // When writing alpha values, the input colors are assumed to be post
+  // multiplied.
+  //
+  // size: dimensions of the image
+  // row_byte_width: the width in bytes of each row. This may be greater than
+  //   w * bytes_per_pixel if there is extra padding at the end of each row
+  //   (often, each row is padded to the next machine word).
+  // discard_transparency: when true, and when the input data format includes
+  //   alpha values, these alpha values will be discarded and only RGB will be
+  //   written to the resulting file. Otherwise, alpha values in the input
+  //   will be preserved.
+  // comments: comments to be written in the png's metadata.
+  // compression_level: An integer between -1 and 9, corresponding to zlib's
+  //   compression levels. -1 is the default.
+  static bool EncodeWithCompressionLevel(const unsigned char* input,
+                                         ColorFormat format,
+                                         const Size& size,
+                                         int row_byte_width,
+                                         bool discard_transparency,
+                                         const std::vector<Comment>& comments,
+                                         int compression_level,
+                                         std::vector<unsigned char>* output);
+
+  // Call PNGCodec::Encode on the supplied SkBitmap |input|, which is assumed
+  // to be BGRA, 32 bits per pixel. The params |discard_transparency| and
+  // |output| are passed directly to Encode; refer to Encode for more
+  // information. During the call, an SkAutoLockPixels lock is held on |input|.
+  static bool EncodeBGRASkBitmap(const SkBitmap& input,
+                                 bool discard_transparency,
+                                 std::vector<unsigned char>* output);
+
+  // Decodes the PNG data contained in input of length input_size. The
+  // decoded data will be placed in *output with the dimensions in *w and *h
+  // on success (returns true). This data will be written in the 'format'
+  // format. On failure, the values of these output variables are undefined.
+  //
+  // This function may not support all PNG types, and it hasn't been tested
+  // with a large number of images, so assume a new format may not work. It's
+  // really designed to be able to read in something written by Encode() above.
+  static bool Decode(const unsigned char* input, size_t input_size,
+                     ColorFormat format, std::vector<unsigned char>* output,
+                     int* w, int* h);
+
+  // Decodes the PNG data directly into the passed in SkBitmap. This is
+  // significantly faster than the vector<unsigned char> version of Decode()
+  // above when dealing with PNG files that are >500K, which a lot of theme
+  // images are. (There are a lot of themes that have a NTP image of about ~1
+  // megabyte, and those require a 7-10 megabyte side buffer.)
+  //
+  // Returns true if data is non-null and can be decoded as a png, false
+  // otherwise.
+  static bool Decode(const unsigned char* input, size_t input_size,
+                     SkBitmap* bitmap);
+
+  // Create a SkBitmap from a decoded BGRA DIB. The caller owns the returned
+  // SkBitmap.
+  static SkBitmap* CreateSkBitmapFromBGRAFormat(
+      std::vector<unsigned char>& bgra, int width, int height);
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(PNGCodec);
+};
+
+}  // namespace gfx
+
+#endif  // UI_GFX_CODEC_PNG_CODEC_H_