root/libmedia/VideoDecoder.h

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// VideoDecoder.h: Video decoding base class.
// 
//   Copyright (C) 2007, 2008, 2009, 2010, 2011 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


#ifndef GNASH_VIDEODECODER_H
#define GNASH_VIDEODECODER_H

#include "GnashImage.h"

#include <boost/noncopyable.hpp>

// Forward declarations
namespace gnash {
        namespace media {
                class EncodedVideoFrame;
        }
}

namespace gnash {
namespace media {

/// Abstract base class for embedded video decoders.
//
/// This very simple design allows, but does not require,
/// the use of threads in an implementation. A user of this class push a frame
/// into the decoder and can subsequently pop a decoded frame. Since the pop()
/// call may block, it is advisable to first call peek() to see if there is a
/// frame ready to be popped.
///
class VideoDecoder : public boost::noncopyable {

public:
  virtual ~VideoDecoder()
  {
  }
  
  /// Push an encoded video frame into the decoder
  //
  /// @param buffer the video frame to decode
  ///
  virtual void push(const EncodedVideoFrame& buffer) = 0;
  
  /// Pop a decoded frame from the decoder. THIS METHOD MAY BLOCK.
  //
  /// @return The decoded video frame, or a NULL-containing auto_ptr if an
  ///         error occurred.
  virtual std::auto_ptr<image::GnashImage> pop() = 0;
  
  /// \brief
  /// Check whether a decoded frame is ready to be popped.
  //
  /// This method will never block.
  ///
  /// @return true if there is a frame ready to be popped.
  ///
  virtual bool peek() = 0;

  /// Get the width in pixels of the Video
  //
  /// @return   The width of a video frame, or 0 until this is known.
  ///           This is used ultimately for the AS Video.width property.
  virtual int width() const = 0;

  /// Get the height in pixels of the Video
  //
  /// @return   The height of a video frame, or 0 until this is known.
  ///           This is used ultimately for the AS Video.height property.
  virtual int height() const = 0;

};

        
} // gnash.media namespace 
} // gnash namespace

#endif // __VIDEODECODER_H__