src/px/biq.c

#ifndef lint
static const char       RCSid[] = "$Id: biq.c,v 2.3 2003/05/13 17:58:33 greg Exp $";
#endif
/*
 *  biq.c - simple greyscale quantization.
 *
 *      9/19/88
 */

#include <string.h>

#include "standard.h"
#include "ciq.h"


biq(dith,nw,synth,cm)
int dith;               /* is dithering desired? 0=no, 1=yes */
int nw;                 /* number of colors wanted in output image */
int synth;              /* synthesize colormap? 0=no, 1=yes */
colormap cm;            /* quantization colormap */
                        /* read if synth=0; always written */
{
    colormap ocm;

    picreadcm(ocm);     /* read original picture's colormap (usually identity)*/

    for (n = 0; n < nw; n++)                    /* also sets n to nw */
        color[0][n] = color[1][n] = color[2][n] = (n*256L+128)/nw;

    picwritecm(color);

    draw_grey(ocm);

    memcpy((void *)cm,(void *)color,sizeof color);
}

/*----------------------------------------------------------------------*/

draw_grey(ocm)
colormap ocm;
{
    register rgbpixel *linin;
    register pixel *linout;
    rgbpixel intmp;
    int outtmp;
    int y;
    register int x;

    linin = line3alloc(xmax);
    linout = linealloc(xmax);

    for (y = 0; y < ymax; y++) {
        picreadline3(y, linin);
        for (x = 0; x < xmax; x++) {
                intmp.r = ocm[0][linin[x].r];
                intmp.g = ocm[1][linin[x].g];
                intmp.b = ocm[2][linin[x].b];
                outtmp = rgb_bright(&intmp);
                linout[x] = (outtmp*n+n/2)/256;
        }
        picwriteline(y, linout);
    }
    free((void *)linin);
    free((void *)linout);
}
Revision:	2.4
Committed:	Mon Jun 30 14:59:12 2003 UTC (20 years, 10 months ago) by schorsch
Content type:	text/plain
Branch:	MAIN
Changes since 2.3:	+4 -2 lines
Log Message:	Replaced most outdated BSD function calls with their posix equivalents, and cleaned up a few other platform dependencies.
#	User	Rev	Content
1	greg	1.1	#ifndef lint
2	schorsch	2.4	static const char RCSid[] = "$Id: biq.c,v 2.3 2003/05/13 17:58:33 greg Exp $";
3	greg	1.1	#endif
4	greg	1.2	/*
5	greg	1.1	* biq.c - simple greyscale quantization.
6			*
7			* 9/19/88
8			*/
9
10	schorsch	2.4	#include <string.h>
11
12	greg	1.5	#include "standard.h"
13	greg	1.1	#include "ciq.h"
14
15
16			biq(dith,nw,synth,cm)
17			int dith; /* is dithering desired? 0=no, 1=yes */
18			int nw; /* number of colors wanted in output image */
19			int synth; /* synthesize colormap? 0=no, 1=yes */
20			colormap cm; /* quantization colormap */
21			/* read if synth=0; always written */
22			{
23			colormap ocm;
24
25			picreadcm(ocm); /* read original picture's colormap (usually identity)*/
26
27			for (n = 0; n < nw; n++) /* also sets n to nw */
28			color[0][n] = color[1][n] = color[2][n] = (n*256L+128)/nw;
29
30			picwritecm(color);
31
32			draw_grey(ocm);
33
34	schorsch	2.4	memcpy((void )cm,(void )color,sizeof color);
35	greg	1.1	}
36
37			/----------------------------------------------------------------------/
38
39			draw_grey(ocm)
40			colormap ocm;
41			{
42			register rgbpixel *linin;
43			register pixel *linout;
44	greg	1.3	rgbpixel intmp;
45			int outtmp;
46	greg	1.1	int y;
47			register int x;
48
49			linin = line3alloc(xmax);
50			linout = linealloc(xmax);
51
52			for (y = 0; y < ymax; y++) {
53			picreadline3(y, linin);
54			for (x = 0; x < xmax; x++) {
55	greg	1.3	intmp.r = ocm[0][linin[x].r];
56			intmp.g = ocm[1][linin[x].g];
57			intmp.b = ocm[2][linin[x].b];
58			outtmp = rgb_bright(&intmp);
59			linout[x] = (outtmp*n+n/2)/256;
60	greg	1.1	}
61			picwriteline(y, linout);
62			}
63	greg	2.2	free((void *)linin);
64			free((void *)linout);
65	greg	1.1	}