nsJPEGEncoder.h
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is JPEG Encoding code
*
* The Initial Developer of the Original Code is
* Google Inc.
* Portions created by the Initial Developer are Copyright (C) 2005
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Brett Wilson <brettw@gmail.com>
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "imgIEncoder.h"
#include "mozilla/ReentrantMonitor.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 : 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 StripAlpha(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();
PRPackedBool 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;
};