text: /******************************************************************************
      QtAV:  Multimedia framework based on Qt and FFmpeg
      Copyright (C) 2012-2016 Wang Bin <wbsecg1@gmail.com>
  
  *   This file is part of QtAV (from 2015)
  
      This library is free software; you can redistribute it and/or
      modify it under the terms of the GNU Lesser General Public
      License as published by the Free Software Foundation; either
      version 2.1 of the License, or (at your option) any later version.
  
      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
  ******************************************************************************/
  
  #ifndef QAV_ENCODER_H
  #define QAV_ENCODER_H
  
  #include <QtAV/QtAV_Global.h>
  #include <QtAV/AVError.h>
  #include <QtAV/Packet.h>
  #include <QtCore/QVariant>
  #include <QtCore/QObject>
  
  namespace QtAV {
  class AVEncoderPrivate;
  class Q_AV_EXPORT AVEncoder : public QObject
  {
      Q_OBJECT
      DPTR_DECLARE_PRIVATE(AVEncoder)
      Q_PROPERTY(int bitRate READ bitRate WRITE setBitRate NOTIFY bitRateChanged)
      Q_PROPERTY(QString codecName READ codecName WRITE setCodecName NOTIFY codecNameChanged)
      Q_PROPERTY(TimestampMode timestampMode READ timestampMode WRITE setTimestampMode NOTIFY timestampModeChanged)
      Q_ENUMS(TimestampMode)
  public:
      enum TimestampMode {
          TimestampMonotonic,
          TimestampCopy,
      };
  
      virtual ~AVEncoder();
      virtual QString name() const = 0;
      virtual QString description() const;
      /*!
       * \brief setCodecName
       * An encoder can support more than 1 codec.
       */
      void setCodecName(const QString& name);
      QString codecName() const;
      bool open();
      bool close();
      bool isOpen() const;
      virtual void flush();
      Packet encoded() const;
  
      /*!
       * used by ff muxer. Be sure all parameters are set. (open?)
       */
      virtual void copyAVCodecContext(void* ctx);
      void* codecContext() const; // TODO: always have a avctx like decoder?
      /*!
       * \brief setBitRate
       * Higher bit rate result in better quality.
       * Default for video: 400000, audio: 64000
       */
      void setBitRate(int value);
      int bitRate() const;
  
      TimestampMode timestampMode() const;
      void setTimestampMode(TimestampMode value);
      /*!
       * \brief setOptions
       * 1. If has key "avcodec", it's value (suboption, a hash or map) will be used to set AVCodecContext use av_opt_set and av_dict_set. A value of hash type is ignored.
       * we can ignore the flags used in av_dict_xxx because we can use hash api.
       * empty value does nothing to current context if it is open, but will clear AVDictionary in the next open.
       * AVDictionary is used in avcodec_open2() and will not change unless user call setOptions().
       * 2. Set QObject properties for AVEncoder. Use AVEncoder::name() or lower case as a key to set properties. If key not found, assume key is "avcodec"
       * 3. If no ket AVEncoder::name() found in the option, set key-value pairs as QObject property-value pairs.
       */
      void setOptions(const QVariantHash &dict);
      QVariantHash options() const;
  
  Q_SIGNALS:
      void error(const QtAV::AVError& e); //explictly use QtAV::AVError in connection for Qt4 syntax
      void codecNameChanged();
      void bitRateChanged();
      void timestampModeChanged(TimestampMode mode);
  protected:
      AVEncoder(AVEncoderPrivate& d);
      DPTR_DECLARE(AVEncoder)
  private:
      Q_DISABLE_COPY(AVEncoder)
      AVEncoder(); // base class, not direct create. only final class has is enough
  };
  } //namespace QtAV
  #endif // QAV_ENCODER_H
  