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libpng/contrib/pngminus/pnm2png.c
Glenn Randers-Pehrson 520a764cd7 Imported from libpng-1.0.6.tar
2009-04-06 16:04:52 -05:00

534 lines
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/*
* pnm2png.c --- conversion from PBM/PGM/PPM-file to PNG-file
* copyright (C) 1999 by Willem van Schaik <willem@schaik.com>
*
* version 1.0 - 1999.10.15 - First version.
*
* Permission to use, copy, modify, and distribute this software and
* its documentation for any purpose and without fee is hereby granted,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear in
* supporting documentation. This software is provided "as is" without
* express or implied warranty.
*/
#include <stdio.h>
#include <stdlib.h>
#ifdef __TURBOC__
#include <mem.h>
#include <fcntl.h>
#endif
#ifndef BOOL
#define BOOL unsigned char
#endif
#ifndef TRUE
#define TRUE (BOOL) 1
#endif
#ifndef FALSE
#define FALSE (BOOL) 0
#endif
#define STDIN 0
#define STDOUT 1
#define STDERR 2
/* to make pnm2png verbose so we can find problems (needs to be before png.h) */
#ifndef PNG_DEBUG
#define PNG_DEBUG 0
#endif
#include "png.h"
/* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */
#ifndef png_jmpbuf
# define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)
#endif
/* function prototypes */
int main (int argc, char *argv[]);
void usage ();
BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace, BOOL alpha);
void get_token(FILE *pnm_file, char *token);
png_uint_32 get_data (FILE *pnm_file, int depth);
png_uint_32 get_value (FILE *pnm_file, int depth);
/*
* main
*/
int main(int argc, char *argv[])
{
FILE *fp_rd = stdin;
FILE *fp_al = NULL;
FILE *fp_wr = stdout;
BOOL interlace = FALSE;
BOOL alpha = FALSE;
int argi;
for (argi = 1; argi < argc; argi++)
{
if (argv[argi][0] == '-')
{
switch (argv[argi][1])
{
case 'i':
interlace = TRUE;
break;
case 'a':
alpha = TRUE;
argi++;
if ((fp_al = fopen (argv[argi], "rb")) == NULL)
{
fprintf (stderr, "PNM2PNG\n");
fprintf (stderr, "Error: alpha-channel file %s does not exist\n",
argv[argi]);
exit (1);
}
break;
case 'h':
case '?':
usage();
exit(0);
break;
default:
fprintf (stderr, "PNM2PNG\n");
fprintf (stderr, "Error: unknown option %s\n", argv[argi]);
usage();
exit(1);
break;
} /* end switch */
}
else if (fp_rd == stdin)
{
if ((fp_rd = fopen (argv[argi], "rb")) == NULL)
{
fprintf (stderr, "PNM2PNG\n");
fprintf (stderr, "Error: file %s does not exist\n", argv[argi]);
exit (1);
}
}
else if (fp_wr == stdout)
{
if ((fp_wr = fopen (argv[argi], "wb")) == NULL)
{
fprintf (stderr, "PNM2PNG\n");
fprintf (stderr, "Error: can not create PNG-file %s\n", argv[argi]);
exit (1);
}
}
else
{
fprintf (stderr, "PNM2PNG\n");
fprintf (stderr, "Error: too many parameters\n");
usage();
exit (1);
}
} /* end for */
#ifdef __TURBOC__
/* set stdin/stdout to binary, we're reading the PNM always! in binary format */
if (fp_rd == stdin)
{
setmode (STDIN, O_BINARY);
}
if (fp_wr == stdout)
{
setmode (STDOUT, O_BINARY);
}
#endif
/* call the conversion program itself */
if (pnm2png (fp_rd, fp_wr, fp_al, interlace, alpha) == FALSE)
{
fprintf (stderr, "PNM2PNG\n");
fprintf (stderr, "Error: unsuccessful converting to PNG-image\n");
exit (1);
}
/* close input file */
fclose (fp_rd);
/* close output file */
fclose (fp_wr);
/* close alpha file */
if (alpha)
fclose (fp_al);
return 0;
}
/*
* usage
*/
void usage()
{
fprintf (stderr, "PNM2PNG\n");
fprintf (stderr, " by Willem van Schaik, 1999\n");
#ifdef __TURBOC__
fprintf (stderr, " for Turbo-C and Borland-C compilers\n");
#else
fprintf (stderr, " for Linux (and Unix) compilers\n");
#endif
fprintf (stderr, "Usage: pnm2png [options] <file>.<pnm> [<file>.png]\n");
fprintf (stderr, " or: ... | pnm2png [options]\n");
fprintf (stderr, "Options:\n");
fprintf (stderr, " -i[nterlace] write png-file with interlacing on\n");
fprintf (stderr, " -a[lpha] <file>.pgm read PNG alpha channel as pgm-file\n");
fprintf (stderr, " -h | -? print this help-information\n");
}
/*
* pnm2png
*/
BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace, BOOL alpha)
{
png_struct *png_ptr = NULL;
png_info *info_ptr = NULL;
png_byte *png_pixels = NULL;
png_byte **row_pointers = NULL;
png_byte *pix_ptr = NULL;
png_uint_32 row_bytes;
char type_token[16];
char width_token[16];
char height_token[16];
char maxval_token[16];
int color_type;
png_uint_32 width, alpha_width;
png_uint_32 height, alpha_height;
png_uint_32 maxval;
int bit_depth = 0;
int channels;
int alpha_depth = 0;
int alpha_present;
int row, col;
BOOL raw, alpha_raw = FALSE;
png_uint_32 tmp16;
int i;
/* read header of PNM file */
get_token(pnm_file, type_token);
if (type_token[0] != 'P')
{
return FALSE;
}
else if ((type_token[1] == '1') || (type_token[1] == '4'))
{
raw = (type_token[1] == '4');
color_type = PNG_COLOR_TYPE_GRAY;
bit_depth = 1;
}
else if ((type_token[1] == '2') || (type_token[1] == '5'))
{
raw = (type_token[1] == '5');
color_type = PNG_COLOR_TYPE_GRAY;
get_token(pnm_file, width_token);
sscanf (width_token, "%lu", &width);
get_token(pnm_file, height_token);
sscanf (height_token, "%lu", &height);
get_token(pnm_file, maxval_token);
sscanf (maxval_token, "%lu", &maxval);
if (maxval <= 1)
bit_depth = 1;
else if (maxval <= 3)
bit_depth = 2;
else if (maxval <= 15)
bit_depth = 4;
else if (maxval <= 255)
bit_depth = 8;
else /* if (maxval <= 65535) */
bit_depth = 16;
}
else if ((type_token[1] == '3') || (type_token[1] == '6'))
{
raw = (type_token[1] == '6');
color_type = PNG_COLOR_TYPE_RGB;
get_token(pnm_file, width_token);
sscanf (width_token, "%lu", &width);
get_token(pnm_file, height_token);
sscanf (height_token, "%lu", &height);
get_token(pnm_file, maxval_token);
sscanf (maxval_token, "%lu", &maxval);
if (maxval <= 1)
bit_depth = 1;
else if (maxval <= 3)
bit_depth = 2;
else if (maxval <= 15)
bit_depth = 4;
else if (maxval <= 255)
bit_depth = 8;
else /* if (maxval <= 65535) */
bit_depth = 16;
}
else
{
return FALSE;
}
/* read header of PGM file with alpha channel */
if (alpha)
{
if (color_type == PNG_COLOR_TYPE_GRAY)
color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
if (color_type == PNG_COLOR_TYPE_RGB)
color_type = PNG_COLOR_TYPE_RGB_ALPHA;
get_token(alpha_file, type_token);
if (type_token[0] != 'P')
{
return FALSE;
}
else if ((type_token[1] == '2') || (type_token[1] == '5'))
{
alpha_raw = (type_token[1] == '5');
get_token(alpha_file, width_token);
sscanf (width_token, "%lu", &alpha_width);
if (alpha_width != width)
return FALSE;
get_token(alpha_file, height_token);
sscanf (height_token, "%lu", &alpha_height);
if (alpha_height != height)
return FALSE;
get_token(alpha_file, maxval_token);
sscanf (maxval_token, "%lu", &maxval);
if (maxval <= 1)
alpha_depth = 1;
else if (maxval <= 3)
alpha_depth = 2;
else if (maxval <= 15)
alpha_depth = 4;
else if (maxval <= 255)
alpha_depth = 8;
else /* if (maxval <= 65535) */
alpha_depth = 16;
if (alpha_depth != bit_depth)
return FALSE;
}
else
{
return FALSE;
}
} /* end if alpha */
/* calculate the number of channels and store alpha-presence */
if (color_type == PNG_COLOR_TYPE_GRAY)
channels = 1;
else if (color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
channels = 2;
else if (color_type == PNG_COLOR_TYPE_RGB)
channels = 3;
else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
channels = 4;
else
channels = 0; /* should not happen */
alpha_present = (channels - 1) % 2;
/* row_bytes is the width x number of channels x (bit-depth / 8) */
row_bytes = width * channels * ((bit_depth <= 8) ? 1 : 2);
if ((png_pixels = (png_byte *) malloc (row_bytes * height * sizeof (png_byte))) == NULL)
return FALSE;
/* read data from PNM file */
pix_ptr = png_pixels;
for (row = 0; row < height; row++)
{
for (col = 0; col < width; col++)
{
for (i = 0; i < (channels - alpha_present); i++)
{
if (raw)
*pix_ptr++ = get_data (pnm_file, bit_depth);
else
if (bit_depth <= 8)
*pix_ptr++ = get_value (pnm_file, bit_depth);
else
{
tmp16 = get_value (pnm_file, bit_depth);
*pix_ptr = (png_byte) ((tmp16 >> 8) & 0xFF);
pix_ptr++;
*pix_ptr = (png_byte) (tmp16 & 0xFF);
pix_ptr++;
}
}
if (alpha) /* read alpha-channel from pgm file */
{
if (alpha_raw)
*pix_ptr++ = get_data (alpha_file, alpha_depth);
else
if (alpha_depth <= 8)
*pix_ptr++ = get_value (alpha_file, bit_depth);
else
{
tmp16 = get_value (alpha_file, bit_depth);
*pix_ptr++ = (png_byte) ((tmp16 >> 8) & 0xFF);
*pix_ptr++ = (png_byte) (tmp16 & 0xFF);
}
} /* if alpha */
} /* end for col */
} /* end for row */
/* prepare the standard PNG structures */
png_ptr = png_create_write_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!png_ptr)
{
return FALSE;
}
info_ptr = png_create_info_struct (png_ptr);
if (!info_ptr)
{
png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
return FALSE;
}
/* setjmp() must be called in every function that calls a PNG-reading libpng function */
if (setjmp (png_jmpbuf(png_ptr)))
{
png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
return FALSE;
}
/* initialize the png structure */
png_init_io (png_ptr, png_file);
/* we're going to write more or less the same PNG as the input file */
png_set_IHDR (png_ptr, info_ptr, width, height, bit_depth, color_type,
(!interlace) ? PNG_INTERLACE_NONE : PNG_INTERLACE_ADAM7,
PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
/* write the file header information */
png_write_info (png_ptr, info_ptr);
/* if needed we will allocate memory for an new array of row-pointers */
if (row_pointers == (unsigned char**) NULL)
{
if ((row_pointers = (png_byte **) malloc (height * sizeof (png_bytep))) == NULL)
{
png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
return FALSE;
}
}
/* set the individual row_pointers to point at the correct offsets */
for (i = 0; i < (height); i++)
row_pointers[i] = png_pixels + i * row_bytes;
/* write out the entire image data in one call */
png_write_image (png_ptr, row_pointers);
/* write the additional chuncks to the PNG file (not really needed) */
png_write_end (png_ptr, info_ptr);
/* clean up after the write, and free any memory allocated */
png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
if (row_pointers != (unsigned char**) NULL)
free (row_pointers);
if (png_pixels != (unsigned char*) NULL)
free (png_pixels);
return TRUE;
} /* end of pnm2png */
/*
* get_token() - gets the first string after whitespace
*/
void get_token(FILE *pnm_file, char *token)
{
int i = 0;
/* remove white-space */
do
{
token[i] = (unsigned char) fgetc (pnm_file);
}
while ((token[i] == '\n') || (token[i] == '\r') || (token[i] == ' '));
/* read string */
do
{
i++;
token[i] = (unsigned char) fgetc (pnm_file);
}
while ((token[i] != '\n') && (token[i] != '\r') && (token[i] != ' '));
token[i] = '\0';
return;
}
/*
* get_data() - takes first byte and converts into next pixel value,
* taking as much bits as defined by bit-depth and
* using the bit-depth to fill up a byte (0Ah -> AAh)
*/
png_uint_32 get_data (FILE *pnm_file, int depth)
{
static int bits_left = 0;
static int old_value = 0;
static int mask = 0;
int i;
png_uint_32 ret_value;
if (mask == 0)
for (i = 0; i < depth; i++)
mask = (mask >> 1) | 0x80;
if (bits_left <= 0)
{
old_value = fgetc (pnm_file);
bits_left = 8;
}
ret_value = old_value & mask;
for (i = 1; i < (8 / depth); i++)
ret_value = ret_value || (ret_value >> depth);
old_value = (old_value << depth) & 0xFF;
bits_left -= depth;
return ret_value;
}
/*
* get_value() - takes first (numeric) string and converts into number,
* using the bit-depth to fill up a byte (0Ah -> AAh)
*/
png_uint_32 get_value (FILE *pnm_file, int depth)
{
static png_uint_32 mask = 0;
png_byte token[16];
png_uint_32 ret_value;
int i = 0;
if (mask == 0)
for (i = 0; i < depth; i++)
mask = (mask << 1) | 0x01;
get_token (pnm_file, (char *) token);
sscanf ((const char *) token, "%lu", &ret_value);
ret_value &= mask;
if (depth < 8)
for (i = 0; i < (8 / depth); i++)
ret_value = (ret_value << depth) || ret_value;
return ret_value;
}
/* end of source */
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