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// Copyright 2017 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 THIRD_PARTY_BLINK_RENDERER_PLATFORM_IMAGE_ENCODERS_IMAGE_ENCODER_H_
#define THIRD_PARTY_BLINK_RENDERER_PLATFORM_IMAGE_ENCODERS_IMAGE_ENCODER_H_
#include "third_party/blink/renderer/platform/platform_export.h"
#include "third_party/blink/renderer/platform/wtf/vector.h"
#include "third_party/libjpeg/jpeglib.h" // for JPEG_MAX_DIMENSION
#include "third_party/libwebp/src/webp/encode.h" // for WEBP_MAX_DIMENSION
#include "third_party/skia/include/core/SkStream.h"
#include "third_party/skia/include/encode/SkJpegEncoder.h"
#include "third_party/skia/include/encode/SkPngEncoder.h"
#include "third_party/skia/include/encode/SkWebpEncoder.h"
namespace blink {
class VectorWStream : public SkWStream {
public:
VectorWStream(Vector<unsigned char>* dst) : dst_(dst) {
DCHECK(dst_);
DCHECK_EQ(0UL, dst->size());
}
bool write(const void* buffer, size_t size) override {
dst_->Append((const unsigned char*)buffer, size);
return true;
}
size_t bytesWritten() const override { return dst_->size(); }
private:
// Does not have ownership.
Vector<unsigned char>* dst_;
};
class PLATFORM_EXPORT ImageEncoder {
public:
static bool Encode(Vector<unsigned char>* dst,
const SkPixmap& src,
const SkJpegEncoder::Options&);
static bool Encode(Vector<unsigned char>* dst,
const SkPixmap& src,
const SkPngEncoder::Options&);
static bool Encode(Vector<unsigned char>* dst,
const SkPixmap& src,
const SkWebpEncoder::Options&);
enum MimeType {
kMimeTypePng,
kMimeTypeJpeg,
kMimeTypeWebp,
kNumberOfMimeTypeSupported
};
static int MaxDimension(MimeType mime_type);
static std::unique_ptr<ImageEncoder> Create(Vector<unsigned char>* dst,
const SkPixmap& src,
const SkJpegEncoder::Options&);
static std::unique_ptr<ImageEncoder> Create(Vector<unsigned char>* dst,
const SkPixmap& src,
const SkPngEncoder::Options&);
bool encodeRows(int numRows) { return encoder_->encodeRows(numRows); }
/**
* If quality is in [0, 1], this will simply convert to a [0, 100]
* integer scale (which is what is used by libjpeg-turbo).
*
* Otherwise, this will return the default value (92).
*/
static int ComputeJpegQuality(double quality);
/**
* Sets Skia encoding options based on the requested quality.
*
* If quality is 1, this will signal a lossless encode.
*
* Otherwise, this will use webp lossy encoding.
* If quality is in [0, 1), this will simply convert to a [0, 100)
* float scale (which is what is used by libwebp). If the quality
* is out of range, this will perform a lossy encode with the default
* value (80).
*/
static SkWebpEncoder::Options ComputeWebpOptions(
double quality,
SkTransferFunctionBehavior unpremulBehavior);
private:
ImageEncoder(Vector<unsigned char>* dst) : dst_(dst) {}
VectorWStream dst_;
std::unique_ptr<SkEncoder> encoder_;
};
};
#endif
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