gecko-dev/image/decoders/nsJPEGDecoder.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef nsJPEGDecoder_h
#define nsJPEGDecoder_h
#include "RasterImage.h"
// On Windows systems, RasterImage.h brings in 'windows.h', which defines INT32.
// But the jpeg decoder has its own definition of INT32. To avoid build issues,
// we need to undefine the version from 'windows.h'.
#undef INT32
#include "Decoder.h"
#include "Downscaler.h"
#include "nsAutoPtr.h"
#include "nsIInputStream.h"
#include "nsIPipe.h"
#include "qcms.h"
extern "C" {
#include "jpeglib.h"
}
#include <setjmp.h>
namespace mozilla {
namespace image {
typedef struct {
struct jpeg_error_mgr pub; // "public" fields for IJG library
jmp_buf setjmp_buffer; // For handling catastropic errors
} decoder_error_mgr;
typedef enum {
JPEG_HEADER, // Reading JFIF headers
JPEG_START_DECOMPRESS,
JPEG_DECOMPRESS_PROGRESSIVE, // Output progressive pixels
JPEG_DECOMPRESS_SEQUENTIAL, // Output sequential pixels
JPEG_DONE,
JPEG_SINK_NON_JPEG_TRAILER, // Some image files have a
// non-JPEG trailer
JPEG_ERROR
} jstate;
class RasterImage;
struct Orientation;
class nsJPEGDecoder : public Decoder
{
public:
nsJPEGDecoder(RasterImage* aImage, Decoder::DecodeStyle aDecodeStyle);
virtual ~nsJPEGDecoder();
virtual nsresult SetTargetSize(const nsIntSize& aSize) MOZ_OVERRIDE;
virtual void InitInternal() MOZ_OVERRIDE;
virtual void WriteInternal(const char* aBuffer, uint32_t aCount) MOZ_OVERRIDE;
virtual void FinishInternal() MOZ_OVERRIDE;
virtual Telemetry::ID SpeedHistogram() MOZ_OVERRIDE;
void NotifyDone();
protected:
Orientation ReadOrientationFromEXIF();
void OutputScanlines(bool* suspend);
Maybe<Downscaler> mDownscaler;
public:
struct jpeg_decompress_struct mInfo;
struct jpeg_source_mgr mSourceMgr;
decoder_error_mgr mErr;
jstate mState;
uint32_t mBytesToSkip;
const JOCTET* mSegment; // The current segment we are decoding from
uint32_t mSegmentLen; // amount of data in mSegment
JOCTET* mBackBuffer;
uint32_t mBackBufferLen; // Offset of end of active backtrack data
uint32_t mBackBufferSize; // size in bytes what mBackBuffer was created with
uint32_t mBackBufferUnreadLen; // amount of data currently in mBackBuffer
JOCTET * mProfile;
uint32_t mProfileLength;
qcms_profile* mInProfile;
qcms_transform* mTransform;
bool mReading;
const Decoder::DecodeStyle mDecodeStyle;
uint32_t mCMSMode;
};
} // namespace image
} // namespace mozilla
#endif // nsJPEGDecoder_h