src/px/biq.c

#ifndef lint
static const char       RCSid[] = "$Id$";
#endif
/*
 *  biq.c - simple greyscale quantization.
 *
 *      9/19/88
 */

#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);

    bcopy((char *)color,(char *)cm,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:	2.2
Committed:	Sat Feb 22 02:07:27 2003 UTC (21 years, 2 months ago) by greg
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rad3R5
Changes since 2.1:	+3 -6 lines
Log Message:	Changes and check-in for 3.5 release Includes new source files and modifications not recorded for many years See ray/doc/notes/ReleaseNotes for notes between 3.1 and 3.5 release
#	User	Rev	Content
1	greg	1.1	#ifndef lint
2	greg	2.2	static const char RCSid[] = "$Id$";
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	greg	1.5	#include "standard.h"
11	greg	1.1	#include "ciq.h"
12
13
14			biq(dith,nw,synth,cm)
15			int dith; /* is dithering desired? 0=no, 1=yes */
16			int nw; /* number of colors wanted in output image */
17			int synth; /* synthesize colormap? 0=no, 1=yes */
18			colormap cm; /* quantization colormap */
19			/* read if synth=0; always written */
20			{
21			colormap ocm;
22
23			picreadcm(ocm); /* read original picture's colormap (usually identity)*/
24
25			for (n = 0; n < nw; n++) /* also sets n to nw */
26			color[0][n] = color[1][n] = color[2][n] = (n*256L+128)/nw;
27
28			picwritecm(color);
29
30			draw_grey(ocm);
31
32	greg	1.4	bcopy((char )color,(char )cm,sizeof color);
33	greg	1.1	}
34
35			/----------------------------------------------------------------------/
36
37			draw_grey(ocm)
38			colormap ocm;
39			{
40			register rgbpixel *linin;
41			register pixel *linout;
42	greg	1.3	rgbpixel intmp;
43			int outtmp;
44	greg	1.1	int y;
45			register int x;
46
47			linin = line3alloc(xmax);
48			linout = linealloc(xmax);
49
50			for (y = 0; y < ymax; y++) {
51			picreadline3(y, linin);
52			for (x = 0; x < xmax; x++) {
53	greg	1.3	intmp.r = ocm[0][linin[x].r];
54			intmp.g = ocm[1][linin[x].g];
55			intmp.b = ocm[2][linin[x].b];
56			outtmp = rgb_bright(&intmp);
57			linout[x] = (outtmp*n+n/2)/256;
58	greg	1.1	}
59			picwriteline(y, linout);
60			}
61	greg	2.2	free((void *)linin);
62			free((void *)linout);
63	greg	1.1	}