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/*
* This file is part of MXE.
* See index.html for further information.
*
* This is a slightly modified version of:
* http://ironalbatross.net/wiki/index.php5?title=CPP_LIBPNG#Minimal_Example_of_writing_a_PNG_File
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <png.h>
int main(int argc, char *argv[])
{
(void)argc;
(void)argv;
/* PNG structs and types */
png_byte color_type;
png_byte bit_depth;
png_structp png_ptr;
png_infop info_ptr;
png_bytep *row_pointers;
int height, width;
FILE *fp;
width = 640;
height = 480;
color_type = PNG_COLOR_TYPE_RGB;
bit_depth = 8; /* Number of bits per color, not per pixel */
/* Dynamic 2D array in C */
row_pointers = (png_bytep *)malloc( sizeof(png_bytep) * height);
int i;
for(i = 0; i < height; i++)
{
int j;
row_pointers[i] = malloc(sizeof(png_byte) * width * 3);
for(j = 0; j < width; j++)
{
row_pointers[i][0+3*j] = i % 255; /* R */
row_pointers[i][1+3*j] = j % 255; /* G */
row_pointers[i][2+3*j] = (i * j) % 255; /* B */
}
}
/* Write the data out to the PNG file */
fp = fopen("test.png","wb");
png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,NULL,NULL,NULL);
info_ptr = png_create_info_struct(png_ptr);
png_init_io(png_ptr,fp);
png_set_IHDR(png_ptr, info_ptr, width, height,
bit_depth, color_type, PNG_INTERLACE_NONE,
PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
png_write_info(png_ptr, info_ptr);
png_write_image(png_ptr, row_pointers);
png_write_end(png_ptr, NULL);
/* Free up memory after use */
for(i = 0; i < height; i++)
{
free(row_pointers[i]);
}
free(row_pointers);
return 0;
}
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