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/*
* Copyright (c) 2010, Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef JPEGImageEncoder_h
#define JPEGImageEncoder_h
#include "platform/geometry/IntSize.h"
#include "wtf/Allocator.h"
#include "wtf/Vector.h"
#include <memory>
namespace blink {
struct ImageDataBuffer;
class PLATFORM_EXPORT JPEGImageEncoderState {
USING_FAST_MALLOC(JPEGImageEncoderState);
WTF_MAKE_NONCOPYABLE(JPEGImageEncoderState);
public:
static std::unique_ptr<JPEGImageEncoderState> create(
const IntSize& imageSize,
const double& quality,
Vector<unsigned char>* output);
JPEGImageEncoderState() {}
virtual ~JPEGImageEncoderState() {}
};
class PLATFORM_EXPORT JPEGImageEncoder {
STATIC_ONLY(JPEGImageEncoder);
public:
enum { ProgressiveEncodeFailed = -1 };
// Encode the image data with a compression quality in [0-100].
// Warning: Calling this method off the main thread may result in data race
// problems; instead, call JPEGImageEncoderState::create on main thread
// first followed by encodeWithPreInitializedState off the main thread will
// be safer.
static bool encode(const ImageDataBuffer&,
const double& quality,
Vector<unsigned char>*);
static bool encodeWithPreInitializedState(
std::unique_ptr<JPEGImageEncoderState>,
const unsigned char*,
int numRowsCompleted = 0);
static int progressiveEncodeRowsJpegHelper(JPEGImageEncoderState*,
unsigned char*,
int,
const double,
double);
static int computeCompressionQuality(const double& quality);
private:
// For callers: provide a reasonable compression quality default.
enum Quality { DefaultCompressionQuality = 92 };
};
} // namespace blink
#endif
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