gecko/image/encoders/jpeg/nsJPEGEncoder.h

80 lines
2.2 KiB
C++

/* -*- 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/. */
#include "imgIEncoder.h"
#include "mozilla/ReentrantMonitor.h"
#include "mozilla/Attributes.h"
#include "nsCOMPtr.h"
// needed for JPEG library
#include <stdio.h>
extern "C" {
#include "jpeglib.h"
}
#define NS_JPEGENCODER_CID \
{ /* ac2bb8fe-eeeb-4572-b40f-be03932b56e0 */ \
0xac2bb8fe, \
0xeeeb, \
0x4572, \
{0xb4, 0x0f, 0xbe, 0x03, 0x93, 0x2b, 0x56, 0xe0} \
}
// Provides JPEG encoding functionality. Use InitFromData() to do the
// encoding. See that function definition for encoding options.
class nsJPEGEncoder MOZ_FINAL : public imgIEncoder
{
typedef mozilla::ReentrantMonitor ReentrantMonitor;
public:
NS_DECL_ISUPPORTS
NS_DECL_IMGIENCODER
NS_DECL_NSIINPUTSTREAM
NS_DECL_NSIASYNCINPUTSTREAM
nsJPEGEncoder();
private:
~nsJPEGEncoder();
protected:
void ConvertHostARGBRow(const PRUint8* aSrc, PRUint8* aDest,
PRUint32 aPixelWidth);
void ConvertRGBARow(const PRUint8* aSrc, PRUint8* aDest, PRUint32 aPixelWidth);
static void initDestination(jpeg_compress_struct* cinfo);
static boolean emptyOutputBuffer(jpeg_compress_struct* cinfo);
static void termDestination(jpeg_compress_struct* cinfo);
static void errorExit(jpeg_common_struct* cinfo);
void NotifyListener();
bool mFinished;
// image buffer
PRUint8* mImageBuffer;
PRUint32 mImageBufferSize;
PRUint32 mImageBufferUsed;
PRUint32 mImageBufferReadPoint;
nsCOMPtr<nsIInputStreamCallback> mCallback;
nsCOMPtr<nsIEventTarget> mCallbackTarget;
PRUint32 mNotifyThreshold;
/*
nsJPEGEncoder is designed to allow one thread to pump data into it while another
reads from it. We lock to ensure that the buffer remains append-only while
we read from it (that it is not realloced) and to ensure that only one thread
dispatches a callback for each call to AsyncWait.
*/
ReentrantMonitor mReentrantMonitor;
};