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decoder.h

/*-
 * Copyright (c) 1993-1995 The Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and the Network Research Group at
 *      Lawrence Berkeley Laboratory.
 * 4. Neither the name of the University nor of the Laboratory may be used
 *    to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef vat_decoder_h
#define vat_decoder_h

#include "Tcl.h"
#include "source.h"
#include "controller.h"

/*XXX*/
#define PLAYO_FILTER 5
#define VAR_FILTER 5
#define VAR_MULT 2

class Decoder : public PacketHandler {
    protected:
      Decoder();
    public:
      virtual ~Decoder();

      /* statistics */
      void info(char* wrk) const;
      virtual void stats(char* wrk);
      virtual int command(int argc, const char*const* argv);
    protected:
      void consume_samples(const rtphdr* rh, const u_int8_t* p, int cc);
      void count(int statno);
      void setstat(int statno, u_int v);
      int adapt(const rtphdr*, u_int32_t sclock);
      int active() const;
      inline u_int32_t playout() const { return (playout_ >> PLAYO_FILTER); }
/*XXX*/
#define MAXSTAT 16
      struct statcntr {
            const char* name;
            u_int cnt;
      } stat_[MAXSTAT];
      int nstat_;

      Controller* controller_;

      /*
       * Playback point estimation state.
       */
      int32_t var_;           // variance in this host's interarrival time
      u_int32_t hostoffset_;  // timestamp offset this host's clock
      u_int32_t predicted_drop_;    // ts of last drop + blocksize
      u_int32_t playout_;     // playout delay (in media units)
      u_int32_t lastrecv_;    // local time (in media time) of last recv
      int lecture_mode_;      /*XXX*/
      int framesize_;         /*XXX*/
      int block_size_;
      int maxdel_;
};

class PCM_Decoder : public Decoder {
    public:
      virtual void recv(const struct rtphdr*, const u_char* data, int len);
};

inline int Decoder::active() const
{
      return (controller_ && controller_->active());
}

/*
 * Decode steps:
 *    1. decode (to get blocksize)
 *    2. adapt (now that we have blocksize)
 *    3. mix (now that we have adapted)
 */
inline void Decoder::consume_samples(const rtphdr* rh, const u_int8_t* p,
                               int cc)
{
      block_size_ = cc;
      int plout = adapt(rh, controller_->media_ts());
      if (plout >= 0)
            controller_->mix_from_net(plout, p, cc);
}

inline void Decoder::count(int statno)
{
      ++stat_[statno].cnt;
}

inline void Decoder::setstat(int statno, u_int v)
{
      stat_[statno].cnt = v;
}

#endif

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