GnashImageJpeg.h

Go to the documentation of this file.

// GnashImageJpeg.h:  Jpeg reader, for Gnash.
// 
//   Copyright (C) 2008, 2009, 2010 Free Software Foundation, Inc.
// 
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 3 of the License, or
// (at your option) any later version.
// 
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// 
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
//
//
// Original version by Thatcher Ulrich <tu@tulrich.com> 2002
//

#ifndef GNASH_IMAGE_JPEG_H
#define GNASH_IMAGE_JPEG_H

#include <csetjmp>

#include "dsodefs.h"
#include "GnashImage.h"

// jpeglib.h redefines HAVE_STDLIB_H. This silences
// the warnings, but it's not good.
#undef HAVE_STDLIB_H
extern "C" {
#include <jpeglib.h>
}
#undef HAVE_STDLIB_H

// Forward declarations
namespace gnash { class IOChannel; }

namespace gnash {
namespace image {

//
class JpegInput : public Input
{

private:

    const char* _errorOccurred;

    std::jmp_buf _jmpBuf;

    // State needed for input.
    jpeg_decompress_struct m_cinfo;
    jpeg_error_mgr m_jerr;

    bool _compressorOpened;

public:

    //
    DSOEXPORT JpegInput(boost::shared_ptr<IOChannel> in);

    //
    void DSOEXPORT readHeader(unsigned int maxHeaderBytes);

    ~JpegInput();

    void read();

    //
    DSOEXPORT void discardPartialBuffer();

    //
    void finishImage();

    //
    size_t getHeight() const;

    //
    size_t getWidth() const;

    //
    size_t getComponents() const;

    //
    void readScanline(unsigned char* rgbData);

    //
    static std::auto_ptr<Input> create(boost::shared_ptr<IOChannel> in)
    {
        std::auto_ptr<Input> ret(new JpegInput(in));
        // might throw an exception (I guess)
        if (ret.get()) ret->read();
        return ret;
    }

    //
    DSOEXPORT static std::auto_ptr<GnashImage> readSWFJpeg2WithTables(
            JpegInput& loader);

    //
    //
    static std::auto_ptr<JpegInput> createSWFJpeg2HeaderOnly(
            boost::shared_ptr<IOChannel> in, unsigned int maxHeaderBytes)
    {
        std::auto_ptr<JpegInput> ret (new JpegInput(in));
        // might throw an exception
        if (ret.get()) ret->readHeader(maxHeaderBytes);
        return ret;
    }

    //
    void errorOccurred(const char* msg);


};

// Class for writing JPEG image data.
class JpegOutput : public Output
{

public:

    //
    JpegOutput(boost::shared_ptr<IOChannel> out, size_t width,
            size_t height, int quality);
    
    ~JpegOutput();

    //
    void writeImageRGB(const unsigned char* rgbData);

    //
    static std::auto_ptr<Output> create(boost::shared_ptr<IOChannel> out,
            size_t width, size_t height, int quality);
    
private:

    jpeg_compress_struct m_cinfo;
    jpeg_error_mgr m_jerr;
    
};

} // namespace image
} // namespace gnash

#endif // JPEG_H

// Local Variables:
// mode: C++
// c-basic-offset: 8 
// tab-width: 8
// indent-tabs-mode: t
// End: