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diff --git a/libk3b/plugin/k3baudiodecoder.h b/libk3b/plugin/k3baudiodecoder.h
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+/* 
+ *
+ * $Id: k3baudiodecoder.h 619556 2007-01-03 17:38:12Z trueg $
+ * Copyright (C) 2003 Sebastian Trueg <trueg@k3b.org>
+ *
+ * This file is part of the K3b project.
+ * Copyright (C) 1998-2007 Sebastian Trueg <trueg@k3b.org>
+ *
+ * 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 2 of the License, or
+ * (at your option) any later version.
+ * See the file "COPYING" for the exact licensing terms.
+ */
+
+#ifndef _K3B_AUDIO_DECODER_H_
+#define _K3B_AUDIO_DECODER_H_
+
+
+#include <k3bplugin.h>
+#include <k3bmsf.h>
+#include "k3b_export.h"
+#include <kurl.h>
+
+
+
+/**
+ * Abstract streaming class for all the audio input.
+ * Has to output data in the following format:
+ * MSBLeft LSBLeft MSBRight LSBRight (big endian byte order)
+ *
+ * Instances are created by K3bAudioDecoderFactory
+ **/
+class LIBK3B_EXPORT K3bAudioDecoder : public QObject
+{
+  Q_OBJECT
+
+ public:
+  K3bAudioDecoder( QObject* parent = 0, const char* name = 0 );
+  virtual ~K3bAudioDecoder();
+
+
+  /**
+   * Set the file to decode. Be aware that one cannot rely 
+   * on the file length until analyseFile() has been called.
+   */
+  void setFilename( const QString& );
+
+  /**
+   * Since this may take a while depending on the filetype it is best
+   * to run it in a separate thread.
+   *
+   * This method will also call initDecoder().
+   */
+  bool analyseFile();
+
+  /**
+   * @return true if the file was successfully analysed by analyseFile.
+   */
+  bool isValid() const;
+
+  /**
+   * Initialize the decoding.
+   * Normally there is no need to call this as analyseFile already does so.
+   */
+  bool initDecoder();
+
+  /**
+   * initialize the decoding.
+   * @param startOffset the number of frames to skip at the beginning of the file.
+   *
+   * This is the same as calling: initDecoder() and seek(startOffset)
+   */
+  bool initDecoder( const K3b::Msf& startOffset );
+
+  enum MetaDataField {
+    META_TITLE,
+    META_ARTIST,
+    META_SONGWRITER,
+    META_COMPOSER,
+    META_COMMENT
+  };
+
+  /**
+   * This should at least support "Title" and "Artist"
+   *
+   * the default implementation returns the infos set via @p addMetaInfo
+   * and uses KFileMetaInfo if none was set
+   */ 
+  virtual QString metaInfo( MetaDataField );
+
+  /**
+   * The filetype is only used for informational purposes.
+   * It is not necessary but highly recommended to implement this method
+   * as it enhances usability.
+   * @returne The filetype of the decoded file.
+   */
+  virtual QString fileType() const { return QString::null; }
+
+  /**
+   * This method may be reimplemented to provide technical information about
+   * the file. It should return localized strings.
+   *
+   * the default implementation returns the infos set via @p addTechnicalInfo
+   */
+  virtual QStringList supportedTechnicalInfos() const;
+
+  /**
+   * The framework will call this method with all strings returned by the
+   * supportedTechnicalInfos() method. It should return localized strings.
+   *
+   * the default implementation returns the infos set via @p addTechnicalInfo
+   */
+  virtual QString technicalInfo( const QString& ) const;
+
+  /**
+   * returnes -1 on error, 0 when finished, length of data otherwise
+   * takes care of padding
+   * calls decodeInternal() to actually decode data
+   *
+   * Fill the data buffer with maximal maxLen bytes.
+   */
+  int decode( char* data, int maxLen );
+
+  /**
+   * Cleanup after decoding like closing files.
+   * Be aware that this is the counterpart to @p initDecoder().
+   *
+   * There might happen multiple calls to initDecoder() and cleanup(). 
+   */
+  virtual void cleanup();
+
+  /**
+   * Seek to the position pos.
+   * Decoding is started new. That means that the data will be padded to
+   * length() - pos.
+   * returnes true on success;
+   */
+  bool seek( const K3b::Msf& pos );
+
+  /**
+   * Be aware that one cannot rely 
+   * on the file length until analyseFile() has been called.
+   */
+  virtual K3b::Msf length() const { return m_length; }
+
+  const QString& filename() const { return m_fileName; }
+
+  // some helper methods
+  static void fromFloatTo16BitBeSigned( float* src, char* dest, int samples );
+  static void from16bitBeSignedToFloat( char* src, float* dest, int samples );
+  static void from8BitTo16BitBeSigned( char* src, char* dest, int samples );
+
+ protected:
+  /**
+   * Use this method if using the default implementation of @p metaInfo
+   */
+  void addMetaInfo( MetaDataField, const QString& );
+
+  /**
+   * Use this method if using the default implementation of @p technicalInfo
+   * and @p supportedTechnicalInfos.
+   */
+  void addTechnicalInfo( const QString&, const QString& );
+
+  /**
+   * This will be called once before the first call to decodeInternal.
+   * Use it to initialize decoding structures if necessary.
+   *
+   * There might happen multiple calls to initDecoder() and cleanup(). 
+   */
+  virtual bool initDecoderInternal() = 0;
+
+  /**
+   * This method should analyze the file to determine the exact length,
+   * the samplerate in Hz, and the number of channels. The framework takes care of
+   * resampling and converting mono to stereo data.
+   * This method may be time consuming.
+   */
+  virtual bool analyseFileInternal( K3b::Msf& length, int& samplerate, int& channels ) = 0;
+
+  /**
+   * fill the already allocated data with maximal maxLen bytes of decoded samples.
+   * The framework will take care of padding or cutting the decoded data as well
+   * as resampling to 44100 Hz and converting mono samples to stereo.
+   */
+  virtual int decodeInternal( char* data, int maxLen ) = 0;
+
+  virtual bool seekInternal( const K3b::Msf& ) { return false; }
+
+ private:
+  int resample( char* data, int maxLen );
+
+  QString m_fileName;
+  K3b::Msf m_length;
+
+  class Private;
+  Private* d;
+};
+
+
+
+/**
+ * PluginFactory that needs to be subclassed in order to create an
+ * audio decoder.
+ * We need this because K3b uses multiple AudioDecoders of the same type at the 
+ * same time.
+ */
+class LIBK3B_EXPORT K3bAudioDecoderFactory : public K3bPlugin
+{
+  Q_OBJECT
+
+ public:
+  K3bAudioDecoderFactory( QObject* parent = 0, const char* name = 0 )
+    : K3bPlugin( parent, name ) {
+  }
+
+  virtual ~K3bAudioDecoderFactory() {
+  }
+
+  QString group() const { return "AudioDecoder"; }
+
+  /**
+   * K3b uses this flag to decide which plugins to test first
+   * when searching for an audio decoder.
+   *
+   * Decoders that are specialized on one format are favored over
+   * multi-format-decoders.
+   */
+  virtual bool multiFormatDecoder() const { return false; }
+
+  /**
+   * This is the most important method of the AudioDecoderFactory.
+   * It is used to determine if a certain file can be decoded by the
+   * decoder this factory creates.
+   * It is important that this method does not work lazy since it will
+   * be called with urls to every kind of files and if it returns true
+   * a decoder of this type is used for the file.
+   */
+  virtual bool canDecode( const KURL& filename ) = 0;
+
+  virtual K3bAudioDecoder* createDecoder( QObject* parent = 0, const char* name = 0 ) const = 0;
+
+  /**
+   * Searching for an audiodecoder for @p filename.
+   *
+   * It first searches the single format decoder and the the multiformat decoder.
+   *
+   * @returns a newly created decoder on success and 0 when no decoder could be found.
+   */
+  static K3bAudioDecoder* createDecoder( const KURL& url );
+};
+
+#endif