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/*********************************************************************/
/* pgmnoise - create a portable graymap with white noise */
/* Frank Neumann, October 1993 */
/* V1.1 16.11.1993 */
/* */
/* version history: */
/* V1.0 12.10.1993 first version */
/* V1.1 16.11.1993 Rewritten to be NetPBM.programming conforming */
/*********************************************************************/
#include <unistd.h>
#include "pgm.h"
/* global variables */
#ifdef AMIGA
static char *version = "$VER: pgmnoise 1.1 (16.11.93)"; /* Amiga version identification */
#endif
/**************************/
/* start of main function */
/**************************/
int main(argc, argv)
int argc;
char *argv[];
{
int argn, rows, cols, i, j;
gray *destrow;
const char * const usage = "width height\n width and height are picture dimensions in pixels\n";
time_t timenow;
/* parse in 'default' parameters */
pgm_init(&argc, argv);
argn = 1;
/* parse in dim factor */
if (argn == argc)
pm_usage(usage);
if (sscanf(argv[argn], "%d", &cols) != 1)
pm_usage(usage);
argn++;
if (argn == argc)
pm_usage(usage);
if (sscanf(argv[argn], "%d", &rows) != 1)
pm_usage(usage);
if (cols <= 0 || rows <= 0)
pm_error("picture dimensions should be positive numbers");
++argn;
if (argn != argc)
pm_usage(usage);
/* no error checking required here, ppmlib does it all for us */
destrow = pgm_allocrow(cols);
pgm_writepgminit(stdout, cols, rows, PGM_MAXMAXVAL, 0);
/* get time of day to feed the random number generator */
timenow = time(NULL);
srand(timenow ^ getpid());
/* create the (gray) noise */
for (i = 0; i < rows; i++)
{
for (j = 0; j < cols; j++)
destrow[j] = rand() % (PGM_MAXMAXVAL+1);
/* write out one line of graphic data */
pgm_writepgmrow(stdout, destrow, cols, PGM_MAXMAXVAL, 0);
}
pgm_freerow(destrow);
exit(0);
}
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