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-rw-r--r--base/gfx/png_encoder.cc240
1 files changed, 0 insertions, 240 deletions
diff --git a/base/gfx/png_encoder.cc b/base/gfx/png_encoder.cc
deleted file mode 100644
index 10a60c6..0000000
--- a/base/gfx/png_encoder.cc
+++ /dev/null
@@ -1,240 +0,0 @@
-// 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.
-
-#include "base/basictypes.h"
-#include "base/gfx/png_encoder.h"
-#include "base/logging.h"
-#include "base/scoped_ptr.h"
-#include "third_party/skia/include/core/SkBitmap.h"
-#include "third_party/skia/include/core/SkUnPreMultiply.h"
-
-extern "C" {
-#if defined(USE_SYSTEM_LIBPNG)
-#include <png.h>
-#else
-#include "third_party/libpng/png.h"
-#endif
-}
-
-namespace {
-
-// Converts BGRA->RGBA and RGBA->BGRA.
-void ConvertBetweenBGRAandRGBA(const unsigned char* input, int pixel_width,
- unsigned char* output) {
- for (int x = 0; x < pixel_width; x++) {
- const unsigned char* pixel_in = &input[x * 4];
- unsigned char* pixel_out = &output[x * 4];
- pixel_out[0] = pixel_in[2];
- pixel_out[1] = pixel_in[1];
- pixel_out[2] = pixel_in[0];
- pixel_out[3] = pixel_in[3];
- }
-}
-
-void ConvertRGBAtoRGB(const unsigned char* rgba, int pixel_width,
- unsigned char* rgb) {
- for (int x = 0; x < pixel_width; x++) {
- const unsigned char* pixel_in = &rgba[x * 4];
- unsigned char* pixel_out = &rgb[x * 3];
- pixel_out[0] = pixel_in[0];
- pixel_out[1] = pixel_in[1];
- pixel_out[2] = pixel_in[2];
- }
-}
-
-} // namespace
-
-// Encoder --------------------------------------------------------------------
-//
-// This section of the code is based on nsPNGEncoder.cpp in Mozilla
-// (Copyright 2005 Google Inc.)
-
-namespace {
-
-// Passed around as the io_ptr in the png structs so our callbacks know where
-// to write data.
-struct PngEncoderState {
- PngEncoderState(std::vector<unsigned char>* o) : out(o) {}
- std::vector<unsigned char>* out;
-};
-
-// Called by libpng to flush its internal buffer to ours.
-void EncoderWriteCallback(png_structp png, png_bytep data, png_size_t size) {
- PngEncoderState* state = static_cast<PngEncoderState*>(png_get_io_ptr(png));
- DCHECK(state->out);
-
- size_t old_size = state->out->size();
- state->out->resize(old_size + size);
- memcpy(&(*state->out)[old_size], data, size);
-}
-
-void ConvertBGRAtoRGB(const unsigned char* bgra, int pixel_width,
- unsigned char* rgb) {
- for (int x = 0; x < pixel_width; x++) {
- const unsigned char* pixel_in = &bgra[x * 4];
- unsigned char* pixel_out = &rgb[x * 3];
- pixel_out[0] = pixel_in[2];
- pixel_out[1] = pixel_in[1];
- pixel_out[2] = pixel_in[0];
- }
-}
-
-// Automatically destroys the given write structs on destruction to make
-// cleanup and error handling code cleaner.
-class PngWriteStructDestroyer {
- public:
- PngWriteStructDestroyer(png_struct** ps, png_info** pi) : ps_(ps), pi_(pi) {
- }
- ~PngWriteStructDestroyer() {
- png_destroy_write_struct(ps_, pi_);
- }
- private:
- png_struct** ps_;
- png_info** pi_;
-
- DISALLOW_EVIL_CONSTRUCTORS(PngWriteStructDestroyer);
-};
-
-} // namespace
-
-// static
-bool PNGEncoder::Encode(const unsigned char* input, ColorFormat format,
- int w, int h, int row_byte_width,
- bool discard_transparency,
- std::vector<unsigned char>* output) {
- // Run to convert an input row into the output row format, NULL means no
- // conversion is necessary.
- void (*converter)(const unsigned char* in, int w, unsigned char* out) = NULL;
-
- int input_color_components, output_color_components;
- int png_output_color_type;
- switch (format) {
- case FORMAT_RGB:
- input_color_components = 3;
- output_color_components = 3;
- png_output_color_type = PNG_COLOR_TYPE_RGB;
- discard_transparency = false;
- break;
-
- case FORMAT_RGBA:
- input_color_components = 4;
- if (discard_transparency) {
- output_color_components = 3;
- png_output_color_type = PNG_COLOR_TYPE_RGB;
- converter = ConvertRGBAtoRGB;
- } else {
- output_color_components = 4;
- png_output_color_type = PNG_COLOR_TYPE_RGB_ALPHA;
- converter = NULL;
- }
- break;
-
- case FORMAT_BGRA:
- input_color_components = 4;
- if (discard_transparency) {
- output_color_components = 3;
- png_output_color_type = PNG_COLOR_TYPE_RGB;
- converter = ConvertBGRAtoRGB;
- } else {
- output_color_components = 4;
- png_output_color_type = PNG_COLOR_TYPE_RGB_ALPHA;
- converter = ConvertBetweenBGRAandRGBA;
- }
- break;
-
- default:
- NOTREACHED() << "Unknown pixel format";
- return false;
- }
-
- // Row stride should be at least as long as the length of the data.
- DCHECK(input_color_components * w <= row_byte_width);
-
- png_struct* png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,
- png_voidp_NULL,
- png_error_ptr_NULL,
- png_error_ptr_NULL);
- if (!png_ptr)
- return false;
- png_info* info_ptr = png_create_info_struct(png_ptr);
- if (!info_ptr) {
- png_destroy_write_struct(&png_ptr, NULL);
- return false;
- }
- PngWriteStructDestroyer destroyer(&png_ptr, &info_ptr);
-
- if (setjmp(png_jmpbuf(png_ptr))) {
- // The destroyer will ensure that the structures are cleaned up in this
- // case, even though we may get here as a jump from random parts of the
- // PNG library called below.
- return false;
- }
-
- // Set our callback for libpng to give us the data.
- PngEncoderState state(output);
- png_set_write_fn(png_ptr, &state, EncoderWriteCallback, NULL);
-
- png_set_IHDR(png_ptr, info_ptr, w, h, 8, png_output_color_type,
- PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT,
- PNG_FILTER_TYPE_DEFAULT);
- png_write_info(png_ptr, info_ptr);
-
- if (!converter) {
- // No conversion needed, give the data directly to libpng.
- for (int y = 0; y < h; y ++)
- png_write_row(png_ptr,
- const_cast<unsigned char*>(&input[y * row_byte_width]));
- } else {
- // Needs conversion using a separate buffer.
- unsigned char* row = new unsigned char[w * output_color_components];
- for (int y = 0; y < h; y ++) {
- converter(&input[y * row_byte_width], w, row);
- png_write_row(png_ptr, row);
- }
- delete[] row;
- }
-
- png_write_end(png_ptr, info_ptr);
- return true;
-}
-
-// static
-bool PNGEncoder::EncodeBGRASkBitmap(const SkBitmap& input,
- bool discard_transparency,
- std::vector<unsigned char>* output) {
- static const int bbp = 4;
-
- SkAutoLockPixels lock_input(input);
- DCHECK(input.empty() || input.bytesPerPixel() == bbp);
-
- // SkBitmaps are premultiplied, we need to unpremultiply them.
- scoped_array<unsigned char> divided(
- new unsigned char[input.width() * input.height() * bbp]);
-
- int i = 0;
- for (int y = 0; y < input.height(); y++) {
- for (int x = 0; x < input.width(); x++) {
- uint32 pixel = input.getAddr32(0, y)[x];
-
- int alpha = SkColorGetA(pixel);
- if (alpha != 0 && alpha != 255) {
- SkColor unmultiplied = SkUnPreMultiply::PMColorToColor(pixel);
- divided[i + 0] = SkColorGetR(unmultiplied);
- divided[i + 1] = SkColorGetG(unmultiplied);
- divided[i + 2] = SkColorGetB(unmultiplied);
- divided[i + 3] = alpha;
- } else {
- divided[i + 0] = SkColorGetR(pixel);
- divided[i + 1] = SkColorGetG(pixel);
- divided[i + 2] = SkColorGetB(pixel);
- divided[i + 3] = alpha;
- }
- i += bbp;
- }
- }
-
- return Encode(divided.get(),
- PNGEncoder::FORMAT_RGBA, input.width(), input.height(),
- input.width() * bbp, discard_transparency, output);
-}
generated by cgit v1.1 at 2025-03-03 12:24:05 +0000