www.pudn.com > MPEG2systemsrc.rar > Producer.H

/* Copyright (C) 1995, Tektronix Inc. All Rights Reserved.
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 * arising from the use of these programs.
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*/

/* Producer class */
#ifndef producer_h
#define producer_h

class OutputPort;
class Encoder;

class Producer
{
public:
  Producer (Encoder*);
  void connect (OutputPort*);
  virtual int fill_buffer ();
  virtual int get_nready ();
  int send_partial (int);
protected:
  Encoder* encoder;
  OutputPort* oport;
  char* buf;
  int buf_index;
  int length_stored;
};

/*
 DOCUMENTATION

 Producers write things to OutputPorts.  Typical subclasses are
 TSProducer, PESProducer, PATProducer, MapProducer, etc.  Although
 some of these classes define methods for writing directly on the
 OutputPort (e.g. TSProducer), Producers can also be set up to first
 fill an internal buffer (via the fill_buffer method).  Subsequent
 calls to send_partial will send bytes from the buffer to the OutputPort.

 Public members are:

  Producer (Encoder*);
    The only constructor.  All Producers have an Encoder object
    available for such things are reading a encoder clock for the
    generation of timestamps. 
  
  void connect (OutputPort*);
    To connect to an OutputPort.

  virtual int fill_buffer ();
    Defined in subclasses to fill the buffer, buf.
  
  virtual int get_nready ();
    Returns the number of bytes ready for output (e.g. what's left in
    the buffer).
  
  int send_partial (int);
    Will send a specified number of bytes to the OutputPort.  If the
    number requested exceeds the number available in the buffer, then
    the output is padded with 0xff bytes.  
*/

#endif