www.pudn.com > XvidQP.rar > ibitstr.h

/*  ibitstr.cpp 
 * 
 *  Input bitstream class declarations 
 */ 
 
/* 
 *  @(#) ibitstream.h 1.5, last edit: 6/15/94 16:55:34 
 *  @(#) Copyright (C) 1993, 1994 Tobias Bading (bading@cs.tu-berlin.de) 
 *  @(#) Berlin University of Technology 
 * 
 *  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. 
 * 
 *  This program 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 General Public License for more details. 
 * 
 *  You should have received a copy of the GNU General Public License 
 *  along with this program; if not, write to the Free Software 
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 
 */ 
 
/* 
 *  Changes made by Jeff Tsay : 
 *  04/14/97 : Added function prototypes for new syncing and seeking 
 *  mechanisms. Also made this file portable. 
 */ 
 
#ifndef BITSTREAM_H 
#define BITSTREAM_H 
 
#ifdef __WIN32__ 
#define STRICT 
#include  
#endif // __WIN32__ 
 
#include "all.h" 
 
enum e_syncmode { INITIAL_SYNC, STRICT_SYNC }; 
 
class Header;	// forward declaration so we can use the type 
 
const uint32 bufferintsize = 433; 
	// max. 1730 bytes per frame: 144 * 384kbit/s / 32000 Hz + 2 Bytes CRC 
 
// Class to extract bitstrings from files: 
class Ibitstream 
{ 
 
private: 
 
#ifdef __WIN32__ 
  HANDLE fd; 
#else 
  int fd; 
#endif 
 
  uint32	buffer[bufferintsize]; 
  uint32	framesize;		// number of valid bytes in buffer 
  uint32	*wordpointer;	// position of next unsigned int for get_bits() 
  uint32	bitindex;		// number (0-31, from MSB to LSB) of next bit for get_bits() 
  uint32 syncword; 
  bool   single_ch_mode; 
 
  int32  current_frame_number; 
 
#ifdef SEEK_STOP 
  int32  last_frame_number; 
#endif 
 
  bool   copy;          // true if this is a copy (don't close file handle) 
 
public: 
 
  Ibitstream(const char *filename); 
  Ibitstream(const Ibitstream &s0); 
  Ibitstream(); 
 
  Ibitstream &operator = (const Ibitstream &s0); 
 
  ~Ibitstream(); 
 
  bool	get_header(uint32 *headerstring , enum e_syncmode syncmode); 
		// get next 32 bits from bitstream in an unsigned int, 
		// returned value False => end of stream 
  bool	read_frame(uint32 bytesize); 
		// fill buffer with data from bitstream, returned value False => end of stream 
  uint32	get_bits(uint32 number_of_bits); 
		// read bits (1 <= number_of_bits <= 16) from buffer into the lower bits 
		// of an unsigned int. The LSB contains the latest read bit of the stream. 
 
  void   set_syncword(uint32 syncword0); 
  		// Set the word we want to sync the header to, in 
      // Big-Endian byte order 
 
  int32  current_frame() const { return(current_frame_number); } 
 
  uint32 file_size() const; 
		// Returns the size, in bytes, of the input file. 
  uint32 file_pos() const; 
		// Returns the position 
 
  // Stream searching routines (Jeff Tsay) 
 
#ifdef SEEK_STOP 
 
  int32  last_frame() const { return(last_frame_number); } 
 
  bool   seek(int32 frames, int32 frame_size); 
		// Seeks to frames 
 
  bool   seek_pad(int32 frames, int32 frame_size, 
  						Header *header, uint32 *offset); 
		// Seeks frames for 44.1 or 22.05 kHz (padded) files 
 
#endif 
 
  void reset(); 
 
}; 
 
#endif