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/****************************************************************************/
/* */
/* Program: example.c */
/* Author: Simon A.J. Winder */
/* Date: Thu Oct 20 20:45:30 1994 */
/* Copyright (C) 1994 Simon A.J. Winder */
/* */
/* Demonstration program to invert the pixels in a pgm image. */
/* compile with: */
/* gcc example.c -o example -ILibSrc -LLibSrc -limg */
/* or gcc example.c -o example LibSrc/libimg.a -ILibSrc */
/* If you have xv and an image then test with: */
/* example <venice.pgm |xv - */
/* */
/****************************************************************************/
#include <stdio.h>
#include "image.h"
int main(void)
{
it_image *image;
int x,y,width,height,pix;
/* Read in the image from stdin */
image=i_read_image_file(stdin,IT_BYTE,IM_CONTIG);
if(image==NULL)
{
/* Error case - Note that to print messages you need to */
/* use stderr because stdout is already used to output */
/* the image. */
fprintf(stderr,"Error: failed to import image file.\n");
return(1);
}
/* Find out how big it is */
width=image->width;
height=image->height;
/* Invert the pixels */
for(y=0;y<height;y++)
for(x=0;x<width;x++)
{
pix=im_byte_value(image,x,y);
pix=255-pix;
im_byte_value(image,x,y)=pix;
}
/* Write the image out to stdout */
i_write_image_file(stdout,image,IF_BINARY);
return(0);
}
/* Version 1.1 (Nov 1994) */
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