| // Copyright (c) 2006-2008 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 BASE_GFX_PNG_DECODER_H_ |
| #define BASE_GFX_PNG_DECODER_H_ |
| |
| #include <vector> |
| |
| #include "base/basictypes.h" |
| |
| class SkBitmap; |
| |
| // Interface for 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 PNGDecoder { |
| 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 |
| }; |
| |
| // 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); |
| |
| // A convenience function for decoding PNGs as previously encoded by the PNG |
| // encoder. Chrome encodes png in the format PNGDecoder::FORMAT_BGRA. |
| // |
| // Returns true if data is non-null and can be decoded as a png, false |
| // otherwise. |
| static bool Decode(const std::vector<unsigned char>* data, SkBitmap* icon); |
| |
| // 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(PNGDecoder); |
| }; |
| |
| #endif // BASE_GFX_PNG_DECODER_H_ |