text: /***************************************************************************
      copyright            : (C) 2002 - 2008 by Scott Wheeler
      email                : wheeler@kde.org
   ***************************************************************************/
  
  /***************************************************************************
   *   This library is free software; you can redistribute it and/or modify  *
   *   it under the terms of the GNU Lesser General Public License version   *
   *   2.1 as published by the Free Software Foundation.                     *
   *                                                                         *
   *   This library 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     *
   *   Lesser General Public License for more details.                       *
   *                                                                         *
   *   You should have received a copy of the GNU Lesser General Public      *
   *   License along with this library; if not, write to the Free Software   *
   *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA         *
   *   02110-1301  USA                                                       *
   *                                                                         *
   *   Alternatively, this file is available under the Mozilla Public        *
   *   License Version 1.1.  You may obtain a copy of the License at         *
   *   http://www.mozilla.org/MPL/                                           *
   ***************************************************************************/
  
  #ifndef TAGLIB_AUDIOPROPERTIES_H
  #define TAGLIB_AUDIOPROPERTIES_H
  
  #include "taglib_export.h"
  
  namespace TagLib {
  
    //! A simple, abstract interface to common audio properties
  
    /*!
     * The values here are common to most audio formats.  For more specific, codec
     * dependent values, please see see the subclasses APIs.  This is meant to
     * compliment the TagLib::File and TagLib::Tag APIs in providing a simple
     * interface that is sufficient for most applications.
     */
  
    class TAGLIB_EXPORT AudioProperties
    {
    public:
  
      /*!
       * Reading audio properties from a file can sometimes be very time consuming
       * and for the most accurate results can often involve reading the entire
       * file.  Because in many situations speed is critical or the accuracy of the
       * values is not particularly important this allows the level of desired
       * accuracy to be set.
       */
      enum ReadStyle {
        //! Read as little of the file as possible
        Fast,
        //! Read more of the file and make better values guesses
        Average,
        //! Read as much of the file as needed to report accurate values
        Accurate
      };
  
      /*!
       * Destroys this AudioProperties instance.
       */
      virtual ~AudioProperties();
  
      /*!
       * Returns the length of the file in seconds.
       */
      virtual int length() const = 0;
  
      /*!
       * Returns the length of the file in seconds.  The length is rounded down to
       * the nearest whole second.
       *
       * \see lengthInMilliseconds()
       */
      // BIC: make virtual
      int lengthInSeconds() const;
  
      /*!
       * Returns the length of the file in milliseconds.
       *
       * \see lengthInSeconds()
       */
      // BIC: make virtual
      int lengthInMilliseconds() const;
  
      /*!
       * Returns the most appropriate bit rate for the file in kb/s.  For constant
       * bitrate formats this is simply the bitrate of the file.  For variable
       * bitrate formats this is either the average or nominal bitrate.
       */
      virtual int bitrate() const = 0;
  
      /*!
       * Returns the sample rate in Hz.
       */
      virtual int sampleRate() const = 0;
  
      /*!
       * Returns the number of audio channels.
       */
      virtual int channels() const = 0;
  
    protected:
  
      /*!
       * Construct an audio properties instance.  This is protected as this class
       * should not be instantiated directly, but should be instantiated via its
       * subclasses and can be fetched from the FileRef or File APIs.
       *
       * \see ReadStyle
       */
      AudioProperties(ReadStyle style);
  
    private:
      AudioProperties(const AudioProperties &);
      AudioProperties &operator=(const AudioProperties &);
  
      class AudioPropertiesPrivate;
      AudioPropertiesPrivate *d;
    };
  
  }
  
  #endif
  