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/*
* PNM image files loader
*
* copyleft (C) 2005-2010 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
*
* This file is part of MPlayer.
*
* MPlayer is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* MPlayer is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with MPlayer; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* You can alternatively redistribute this file and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*/
/**
* \file pnm_loader.c
* \brief PNM image files loader
*/
#include <stdlib.h>
#include <stdint.h>
#include <stdio.h>
#include <ctype.h>
#include "pnm_loader.h"
/**
* \brief skips whitespace and comments
* \param f file to read from
*/
static void ppm_skip(FILE *f) {
int c, comment = 0;
do {
c = fgetc(f);
if (c == '#')
comment = 1;
if (c == '\n')
comment = 0;
} while (c != EOF && (isspace(c) || comment));
if (c != EOF)
ungetc(c, f);
}
#define MAXDIM (16 * 1024)
uint8_t *read_pnm(FILE *f, int *width, int *height,
int *bytes_per_pixel, int *maxval) {
uint8_t *data;
int type;
unsigned w, h, m, val, bpp;
*width = *height = *bytes_per_pixel = *maxval = 0;
ppm_skip(f);
if (fgetc(f) != 'P')
return NULL;
type = fgetc(f);
if (type != '5' && type != '6')
return NULL;
ppm_skip(f);
if (fscanf(f, "%u", &w) != 1)
return NULL;
ppm_skip(f);
if (fscanf(f, "%u", &h) != 1)
return NULL;
ppm_skip(f);
if (fscanf(f, "%u", &m) != 1)
return NULL;
val = fgetc(f);
if (!isspace(val))
return NULL;
if (w > MAXDIM || h > MAXDIM)
return NULL;
bpp = (m > 255) ? 2 : 1;
if (type == '6')
bpp *= 3;
data = malloc(w * h * bpp);
if (fread(data, w * bpp, h, f) != h) {
free(data);
return NULL;
}
*width = w;
*height = h;
*bytes_per_pixel = bpp;
*maxval = m;
return data;
}
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