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/* pnmhistmap.c -
* Draw a histogram for a PGM or PPM file
*
* Options: -verbose: the usual
* -max N: force scaling value to N
* -black: ignore all-black count
* -white: ignore all-white count
*
* - PGM histogram is a PBM file, PPM histogram is a PPM file
* - No conditional code - assumes all three: PBM, PGM, PPM
*
* Copyright (C) 1993 by Wilson H. Bent, Jr (whb@usc.edu)
*
*/
#include "pnm.h"
/* prototypes */
static void ppm_hist ARGS((FILE *fp));
static void pgm_hist ARGS((FILE *fp));
#define HIST_WIDTH 256
#define HIST_HEIGHT 200
int rows, hist_cols;
xelval maxval;
int format;
int verbose = 0;
int no_black = 0;
int no_white = 0;
int rhist[HIST_WIDTH];
int ghist[HIST_WIDTH];
int bhist[HIST_WIDTH];
int hmax = -1;
double scale;
int
main (argc, argv)
int argc;
char *argv[];
{
FILE *ifp;
int argn = 1;
char *usage = "[-white] [-black] [-max maxvalue] [-verbose] [pnmfile]";
pnm_init (&argc, argv);
/* Check for flags. */
while ( argn < argc && argv[argn][0] == '-' && argv[argn][1] != '\0' ) {
if ( pm_keymatch( argv[argn], "-white", 2 ) )
no_white = 1;
else if ( pm_keymatch( argv[argn], "-black", 2 ) )
no_black = 1;
else if ( pm_keymatch( argv[argn], "-max", 2 ) ) {
if ((hmax = atoi (argv[++argn])) <= 0)
pm_error ("Max. value (%d) must be positive", hmax, 0, 0, 0, 0);
}
else if ( pm_keymatch( argv[argn], "-verbose", 2 ) )
verbose = 1;
else
pm_usage( usage );
++argn;
}
if (--argc > argn)
pm_usage (usage);
else if (argc == argn)
ifp = pm_openr (argv[argn]);
else
ifp = stdin;
pnm_readpnminit (ifp, &hist_cols, &rows, &maxval, &format);
switch (PNM_FORMAT_TYPE (format)) {
case PPM_TYPE:
ppm_hist (ifp);
break;
case PGM_TYPE:
pgm_hist (ifp);
break;
case PBM_TYPE:
pm_error ("no histograms for PBM files", 0, 0, 0, 0, 0);
break;
}
exit (0);
}
static void
ppm_hist (fp)
FILE *fp;
{
pixel *pixrow;
pixel **pixels;
int i, j;
int start, finish;
if ((pixels = ppm_allocarray (HIST_WIDTH, HIST_HEIGHT)) == NULL)
pm_error ("no space for output array (%d pixels)",
HIST_WIDTH * HIST_HEIGHT, 0,0,0,0);
for (i = 0; i < HIST_HEIGHT; ++i)
bzero (pixels[i], HIST_WIDTH * sizeof (pixel));
bzero (rhist, sizeof (rhist));
bzero (ghist, sizeof (ghist));
bzero (bhist, sizeof (bhist));
/* read the pixel values into the histogram arrays */
pixrow = ppm_allocrow (hist_cols);
/*XX error-check! */
if (verbose) pm_message ("making histogram...", 0,0,0,0,0);
for (i = rows; i > 0; --i) {
ppm_readppmrow (fp, pixrow, hist_cols, maxval, format);
for (j = hist_cols-1; j >= 0; --j) {
rhist[PPM_GETR(pixrow[j])]++;
ghist[PPM_GETG(pixrow[j])]++;
bhist[PPM_GETB(pixrow[j])]++;
}
}
ppm_freerow (pixrow);
fclose (fp);
/* find the highest-valued slot and set the scale value */
if (verbose)
pm_message ("finding max. slot height...", 0, 0, 0, 0, 0);
if (hmax == -1) {
start = (no_black ? 1 : 0);
finish = (no_white ? HIST_WIDTH - 1 : HIST_WIDTH);
for (hmax = 0, i = start; i < finish; ++i) {
if (hmax < rhist[i])
hmax = rhist[i];
if (hmax < ghist[i])
hmax = ghist[i];
if (hmax < bhist[i])
hmax = bhist[i];
}
}
for (i = 0; i < HIST_WIDTH; ++i) {
if (rhist[i] > hmax)
rhist[i] = hmax;
if (ghist[i] > hmax)
ghist[i] = hmax;
if (bhist[i] > hmax)
bhist[i] = hmax;
}
if (verbose)
pm_message ("Done: height = %d", hmax, 0, 0, 0, 0);
scale = (double) HIST_HEIGHT / hmax;
for (i = 0; i < HIST_WIDTH; ++i) {
for (j = HIST_HEIGHT - (int)(scale * rhist[i]); j < HIST_HEIGHT; ++j)
PPM_PUTR(pixels[j][i], maxval);
for (j = HIST_HEIGHT - (int)(scale * ghist[i]); j < HIST_HEIGHT; ++j)
PPM_PUTG(pixels[j][i], maxval);
for (j = HIST_HEIGHT - (int)(scale * bhist[i]); j < HIST_HEIGHT; ++j)
PPM_PUTB(pixels[j][i], maxval);
}
ppm_writeppm (stdout, pixels, HIST_WIDTH, HIST_HEIGHT, maxval, 0);
}
static void
pgm_hist (fp)
FILE *fp;
{
gray *grayrow;
bit **bits;
int i, j;
int start, finish;
if ((bits = pbm_allocarray (HIST_WIDTH, HIST_HEIGHT)) == NULL)
pm_error ("no space for output array (%d bits)",
HIST_WIDTH * HIST_HEIGHT, 0,0,0,0);
bzero (ghist, sizeof (ghist));
/* read the pixel values into the histogram arrays */
grayrow = pgm_allocrow (hist_cols);
/*XX error-check! */
if (verbose) pm_message ("making histogram...", 0,0,0,0,0);
for (i = rows; i > 0; --i) {
pgm_readpgmrow (fp, grayrow, hist_cols, maxval, format);
for (j = hist_cols-1; j >= 0; --j)
ghist[grayrow[j]]++;
}
pgm_freerow (grayrow);
fclose (fp);
/* find the highest-valued slot and set the scale value */
if (verbose)
pm_message ("finding max. slot height...", 0, 0, 0, 0, 0);
if (hmax == -1) {
start = (no_black ? 1 : 0);
finish = (no_white ? HIST_WIDTH - 1 : HIST_WIDTH);
for (hmax = 0, i = start; i < finish; ++i)
if (hmax < ghist[i])
hmax = ghist[i];
}
for (i = 0; i < HIST_WIDTH; ++i)
if (ghist[0] > hmax)
ghist[0] = hmax;
if (verbose)
pm_message ("Done: height = %d", hmax, 0, 0, 0, 0);
scale = (double) HIST_HEIGHT / hmax;
for (i = 0; i < HIST_WIDTH; ++i) {
int mark = HIST_HEIGHT - (int)(scale * ghist[i]);
for (j = 0; j < mark; ++j)
bits[j][i] = PBM_BLACK;
for ( ; j < HIST_HEIGHT; ++j)
bits[j][i] = PBM_WHITE;
}
pbm_writepbm (stdout, bits, HIST_WIDTH, HIST_HEIGHT, 0);
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.