plugins/video/H.261-vic/vic/crdef.h

   1 /* crdef.h      (c) 1999-2000 Derek J Smithies (dereks@ibm.net)
   2  *                           Indranet Technologies ltd (lara@indranet.co.nz)
   3  *
   4  * This file is derived from vic, http://www-nrg.ee.lbl.gov/vic/
   5  * Their copyright notice is below.
   6  */
   7 /*
   8  * Copyright (c) 1993-1994 Regents of the University of California.
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. All advertising materials mentioning features or use of this software
  20  *    must display the following acknowledgement:
  21  *      This product includes software developed by the University of
  22  *      California, Berkeley and the Network Research Group at
  23  *      Lawrence Berkeley Laboratory.
  24  * 4. Neither the name of the University nor of the Laboratory may be used
  25  *    to endorse or promote products derived from this software without
  26  *    specific prior written permission.
  27  *
  28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  38  * SUCH DAMAGE.
  39  *
  40  */
  41
  42 /*
  43  * The bit definitions for the values stored in the conditional
  44  * replenishment vector.  We use a variant of the algorithm used
  45  * in nv (which is very similar to the algorithms in many hardware
  46  * codecs) where we only send a block if it changes beyond some threshold
  47  * due to scene motion.  In this case, we send it at a "low-quality"
  48  * to trade of quality for frame rate in areas of high motion.
  49  * We then age the block and after it hasn't changed for a few frames
  50  * we send a higher quality version.  Finally, the process that scans
  51  * the background filling in blocks sends the highest quality version.
  52  *
  53  * A finite state machine defines the algorithm.  When motion is detected,
  54  * the block is reset to state MOTION.  On no motion, it is aged to AGE1,
  55  * AGE2, ... etc., until it reaches state AGEn (the age threshold), and
  56  * then it transitions to IDLE.  If the background process finds a block
  57  * in the IDLE state, it can promote it to the BG state.  On the next
  58  * frame, it reverts to the IDLE state.
  59  *
  60  * Blocks are transmitted only in the MOTION, AGEn, and BG state,
  61  * at low, medium, and high quality, respectively.  The high bit
  62  * is reserved to indicate the block is in one of these states
  63  * and should be sent.
  64  */
  65
  66 /************ Change log
  67  *
  68  * $Log$
  69  * Revision 1.2  2006/07/31 09:09:21  csoutheren
  70  * Checkin of validated codec used during development
  71  *
  72  * Revision 1.1.2.1  2006/04/06 01:17:17  csoutheren
  73  * Initial version of H.261 video codec plugin for OPAL
  74  *
  75  * Revision 2.1  2003/03/15 23:42:59  robertj
  76  * Update to OpenH323 v1.11.7
  77  *
  78  * Revision 1.3  2003/03/14 07:25:55  robertj
  79  * Removed $header keyword so is not different on alternate repositories
  80  *
  81  * Revision 1.2  2000/08/25 03:18:49  dereks
  82  * Add change log facility (Thanks Robert for the info on implementation)
  83  *
  84  *
  85  *
  86  ********/
  87
  88
  89
  90 #define CR_MOTION       0
  91 #define CR_AGETHRESH    31
  92 #define CR_IDLE         0x40
  93 #define CR_BG           0x41
  94 #define CR_SEND         0x80
  95 #define CR_STATE(s)     ((s) & 0x7f)