/************************************************************************ * *  dither.c, pseudo colour dithering for tmndecode (H.263 decoder) *  Copyright (C) 1995, 1996  Telenor R&D, Norway * *  Contacts: *  Robert Danielsen                  <Robert.Danielsen@nta.no> * *  Telenor Research and Development  http://www.nta.no/brukere/DVC/ *  P.O.Box 83                        tel.:   +47 63 84 84 00 *  N-2007 Kjeller, Norway            fax.:   +47 63 81 00 76 * *  Copyright (C) 1997  University of BC, Canada *  Modified by: Michael Gallant <mikeg@ee.ubc.ca> *               Guy Cote <guyc@ee.ubc.ca> *               Berna Erol <bernae@ee.ubc.ca> * *  Contacts: *  Michael Gallant                   <mikeg@ee.ubc.ca> * *  UBC Image Processing Laboratory   http://www.ee.ubc.ca/image *  2356 Main Mall                    tel.: +1 604 822 4051 *  Vancouver BC Canada V6T1Z4        fax.: +1 604 822 5949 * ************************************************************************//* Disclaimer of Warranty *  * These software programs are available to the user without any license fee * or royalty on an "as is" basis. The University of British Columbia * disclaims any and all warranties, whether express, implied, or * statuary, including any implied warranties or merchantability or of * fitness for a particular purpose.  In no event shall the * copyright-holder be liable for any incidental, punitive, or * consequential damages of any kind whatsoever arising from the use of * these programs. *  * This disclaimer of warranty extends to the user of these programs and * user's customers, employees, agents, transferees, successors, and * assigns. *  * The University of British Columbia does not represent or warrant that the * programs furnished hereunder are free of infringement of any * third-party patents. *  * Commercial implementations of H.263, including shareware, are subject to * royalty fees to patent holders.  Many of these patents are general * enough such that they are unavoidable regardless of implementation * design. *  *//* based on mpeg2decode, (C) 1994, MPEG Software Simulation Group and * mpeg2play, (C) 1994 Stefan Eckart <stefan@lis.e-technik.tu-muenchen.de> *  */#ifdef DISPLAY#include <stdio.h>#include <stdlib.h>#include <X11/Xlib.h>#include <X11/Xutil.h>#include "config.h"#include "tmndec.h"#include "global.h"extern unsigned char pixel[256];static unsigned char ytab[16 * (256 + 16)];static unsigned char uvtab[256 * 269 + 270];/****************************************************************************  4x4 ordered dither  Threshold pattern:     0  8  2 10    12  4 14  6     3 11  1  9    15  7 13  5 ****************************************************************************/void ord4x4_dither_init (void){  int i, j, v;  unsigned char ctab[256 + 32];  for (i = 0; i < 256 + 16; i++)  {    v = (i - 8) >> 4;    if (v < 2)      v = 2;    else if (v > 14)      v = 14;    for (j = 0; j < 16; j++)      ytab[16 * i + j] = pixel[(v << 4) + j];  }  for (i = 0; i < 256 + 32; i++)  {    v = (i + 48 - 128) >> 5;    if (v < 0)      v = 0;    else if (v > 3)      v = 3;    ctab[i] = v;  }  for (i = 0; i < 255 + 15; i++)    for (j = 0; j < 255 + 15; j++)      uvtab[256 * i + j] = (ctab[i + 16] << 6) | (ctab[j + 16] << 4) | (ctab[i] << 2) | ctab[j];}void ord4x4_dither_frame (unsigned char *src[], unsigned char *dst){  int i, j;  unsigned char *py = src[0];  unsigned char *pu = src[1];  unsigned char *pv = src[2];  int width, height, cwidth;  if (expand)  {    width = 2 * ref_coded_picture_width;    height = 2 * ref_coded_picture_height;    cwidth = 2 * ref_chrom_width;  } else  {    width = ref_coded_picture_width;    height = ref_coded_picture_height;    cwidth = ref_chrom_width;  }  for (j = 0; j < height; j += 4)  {    register unsigned int uv;    /* line j + 0 */    for (i = 0; i < width; i += 8)    {      uv = uvtab[(*pu++ << 8) | *pv++];      *dst++ = ytab[((*py++) << 4) | (uv & 15)];      *dst++ = ytab[((*py++ + 8) << 4) | (uv >> 4)];      uv = uvtab[((*pu++ << 8) | *pv++) + 1028];      *dst++ = ytab[((*py++ + 2) << 4) | (uv & 15)];      *dst++ = ytab[((*py++ + 10) << 4) | (uv >> 4)];      uv = uvtab[(*pu++ << 8) | *pv++];      *dst++ = ytab[((*py++) << 4) | (uv & 15)];      *dst++ = ytab[((*py++ + 8) << 4) | (uv >> 4)];      uv = uvtab[((*pu++ << 8) | *pv++) + 1028];      *dst++ = ytab[((*py++ + 2) << 4) | (uv & 15)];      *dst++ = ytab[((*py++ + 10) << 4) | (uv >> 4)];    }    pu -= cwidth;    pv -= cwidth;    /* line j + 1 */    for (i = 0; i < width; i += 8)    {      uv = uvtab[((*pu++ << 8) | *pv++) + 2056];      *dst++ = ytab[((*py++ + 12) << 4) | (uv >> 4)];      *dst++ = ytab[((*py++ + 4) << 4) | (uv & 15)];      uv = uvtab[((*pu++ << 8) | *pv++) + 3084];      *dst++ = ytab[((*py++ + 14) << 4) | (uv >> 4)];      *dst++ = ytab[((*py++ + 6) << 4) | (uv & 15)];      uv = uvtab[((*pu++ << 8) | *pv++) + 2056];      *dst++ = ytab[((*py++ + 12) << 4) | (uv >> 4)];      *dst++ = ytab[((*py++ + 4) << 4) | (uv & 15)];      uv = uvtab[((*pu++ << 8) | *pv++) + 3084];      *dst++ = ytab[((*py++ + 14) << 4) | (uv >> 4)];      *dst++ = ytab[((*py++ + 6) << 4) | (uv & 15)];    }    /* line j + 2 */    for (i = 0; i < width; i += 8)    {      uv = uvtab[((*pu++ << 8) | *pv++) + 1542];      *dst++ = ytab[((*py++ + 3) << 4) | (uv & 15)];      *dst++ = ytab[((*py++ + 11) << 4) | (uv >> 4)];      uv = uvtab[((*pu++ << 8) | *pv++) + 514];      *dst++ = ytab[((*py++ + 1) << 4) | (uv & 15)];      *dst++ = ytab[((*py++ + 9) << 4) | (uv >> 4)];      uv = uvtab[((*pu++ << 8) | *pv++) + 1542];      *dst++ = ytab[((*py++ + 3) << 4) | (uv & 15)];      *dst++ = ytab[((*py++ + 11) << 4) | (uv >> 4)];      uv = uvtab[((*pu++ << 8) | *pv++) + 514];      *dst++ = ytab[((*py++ + 1) << 4) | (uv & 15)];      *dst++ = ytab[((*py++ + 9) << 4) | (uv >> 4)];    }    pu -= cwidth;    pv -= cwidth;    /* line j + 3 */    for (i = 0; i < width; i += 8)    {      uv = uvtab[((*pu++ << 8) | *pv++) + 3598];      *dst++ = ytab[((*py++ + 15) << 4) | (uv >> 4)];      *dst++ = ytab[((*py++ + 7) << 4) | (uv & 15)];      uv = uvtab[((*pu++ << 8) | *pv++) + 2570];      *dst++ = ytab[((*py++ + 13) << 4) | (uv >> 4)];      *dst++ = ytab[((*py++ + 5) << 4) | (uv & 15)];      uv = uvtab[((*pu++ << 8) | *pv++) + 3598];      *dst++ = ytab[((*py++ + 15) << 4) | (uv >> 4)];      *dst++ = ytab[((*py++ + 7) << 4) | (uv & 15)];      uv = uvtab[((*pu++ << 8) | *pv++) + 2570];      *dst++ = ytab[((*py++ + 13) << 4) | (uv >> 4)];      *dst++ = ytab[((*py++ + 5) << 4) | (uv & 15)];    }  }}#endif