2 * pnm2png.c --- conversion from PBM/PGM/PPM-file to PNG-file
3 * copyright (C) 1999 by Willem van Schaik <willem@schaik.com>
5 * version 1.0 - 1999.10.15 - First version.
7 * Permission to use, copy, modify, and distribute this software and
8 * its documentation for any purpose and without fee is hereby granted,
9 * provided that the above copyright notice appear in all copies and
10 * that both that copyright notice and this permission notice appear in
11 * supporting documentation. This software is provided "as is" without
12 * express or implied warranty.
24 #define BOOL unsigned char
30 #define FALSE (BOOL) 0
37 /* to make pnm2png verbose so we can find problems (needs to be before png.h) */
44 /* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */
46 # define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)
49 /* function prototypes */
51 int main (int argc
, char *argv
[]);
53 BOOL
pnm2png (FILE *pnm_file
, FILE *png_file
, FILE *alpha_file
, BOOL interlace
, BOOL alpha
);
54 void get_token(FILE *pnm_file
, char *token
);
55 png_uint_32
get_data (FILE *pnm_file
, int depth
);
56 png_uint_32
get_value (FILE *pnm_file
, int depth
);
62 int main(int argc
, char *argv
[])
67 BOOL interlace
= FALSE
;
71 for (argi
= 1; argi
< argc
; argi
++)
73 if (argv
[argi
][0] == '-')
75 switch (argv
[argi
][1])
83 if ((fp_al
= fopen (argv
[argi
], "rb")) == NULL
)
85 fprintf (stderr
, "PNM2PNG\n");
86 fprintf (stderr
, "Error: alpha-channel file %s does not exist\n",
97 fprintf (stderr
, "PNM2PNG\n");
98 fprintf (stderr
, "Error: unknown option %s\n", argv
[argi
]);
104 else if (fp_rd
== stdin
)
106 if ((fp_rd
= fopen (argv
[argi
], "rb")) == NULL
)
108 fprintf (stderr
, "PNM2PNG\n");
109 fprintf (stderr
, "Error: file %s does not exist\n", argv
[argi
]);
113 else if (fp_wr
== stdout
)
115 if ((fp_wr
= fopen (argv
[argi
], "wb")) == NULL
)
117 fprintf (stderr
, "PNM2PNG\n");
118 fprintf (stderr
, "Error: can not create PNG-file %s\n", argv
[argi
]);
124 fprintf (stderr
, "PNM2PNG\n");
125 fprintf (stderr
, "Error: too many parameters\n");
132 /* set stdin/stdout to binary, we're reading the PNM always! in binary format */
135 setmode (STDIN
, O_BINARY
);
139 setmode (STDOUT
, O_BINARY
);
143 /* call the conversion program itself */
144 if (pnm2png (fp_rd
, fp_wr
, fp_al
, interlace
, alpha
) == FALSE
)
146 fprintf (stderr
, "PNM2PNG\n");
147 fprintf (stderr
, "Error: unsuccessful converting to PNG-image\n");
151 /* close input file */
153 /* close output file */
155 /* close alpha file */
168 fprintf (stderr
, "PNM2PNG\n");
169 fprintf (stderr
, " by Willem van Schaik, 1999\n");
171 fprintf (stderr
, " for Turbo-C and Borland-C compilers\n");
173 fprintf (stderr
, " for Linux (and Unix) compilers\n");
175 fprintf (stderr
, "Usage: pnm2png [options] <file>.<pnm> [<file>.png]\n");
176 fprintf (stderr
, " or: ... | pnm2png [options]\n");
177 fprintf (stderr
, "Options:\n");
178 fprintf (stderr
, " -i[nterlace] write png-file with interlacing on\n");
179 fprintf (stderr
, " -a[lpha] <file>.pgm read PNG alpha channel as pgm-file\n");
180 fprintf (stderr
, " -h | -? print this help-information\n");
187 BOOL
pnm2png (FILE *pnm_file
, FILE *png_file
, FILE *alpha_file
, BOOL interlace
, BOOL alpha
)
189 png_struct
*png_ptr
= NULL
;
190 png_info
*info_ptr
= NULL
;
191 png_byte
*png_pixels
= NULL
;
192 png_byte
**row_pointers
= NULL
;
193 png_byte
*pix_ptr
= NULL
;
194 png_uint_32 row_bytes
;
197 char width_token
[16];
198 char height_token
[16];
199 char maxval_token
[16];
201 unsigned long ul_width
=0, ul_alpha_width
=0;
202 unsigned long ul_height
=0, ul_alpha_height
=0;
203 unsigned long ul_maxval
=0;
204 png_uint_32 width
, alpha_width
;
205 png_uint_32 height
, alpha_height
;
212 BOOL raw
, alpha_raw
= FALSE
;
213 #if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
214 BOOL packed_bitmap
= FALSE
;
219 /* read header of PNM file */
221 get_token(pnm_file
, type_token
);
222 if (type_token
[0] != 'P')
226 else if ((type_token
[1] == '1') || (type_token
[1] == '4'))
228 #if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
229 raw
= (type_token
[1] == '4');
230 color_type
= PNG_COLOR_TYPE_GRAY
;
231 get_token(pnm_file
, width_token
);
232 sscanf (width_token
, "%lu", &ul_width
);
233 width
= (png_uint_32
) ul_width
;
234 get_token(pnm_file
, height_token
);
235 sscanf (height_token
, "%lu", &ul_height
);
236 height
= (png_uint_32
) ul_height
;
238 packed_bitmap
= TRUE
;
240 fprintf (stderr
, "PNM2PNG built without PNG_WRITE_INVERT_SUPPORTED and \n");
241 fprintf (stderr
, "PNG_WRITE_PACK_SUPPORTED can't read PBM (P1,P4) files\n");
244 else if ((type_token
[1] == '2') || (type_token
[1] == '5'))
246 raw
= (type_token
[1] == '5');
247 color_type
= PNG_COLOR_TYPE_GRAY
;
248 get_token(pnm_file
, width_token
);
249 sscanf (width_token
, "%lu", &ul_width
);
250 width
= (png_uint_32
) ul_width
;
251 get_token(pnm_file
, height_token
);
252 sscanf (height_token
, "%lu", &ul_height
);
253 height
= (png_uint_32
) ul_height
;
254 get_token(pnm_file
, maxval_token
);
255 sscanf (maxval_token
, "%lu", &ul_maxval
);
256 maxval
= (png_uint_32
) ul_maxval
;
260 else if (maxval
<= 3)
262 else if (maxval
<= 15)
264 else if (maxval
<= 255)
266 else /* if (maxval <= 65535) */
269 else if ((type_token
[1] == '3') || (type_token
[1] == '6'))
271 raw
= (type_token
[1] == '6');
272 color_type
= PNG_COLOR_TYPE_RGB
;
273 get_token(pnm_file
, width_token
);
274 sscanf (width_token
, "%lu", &ul_width
);
275 width
= (png_uint_32
) ul_width
;
276 get_token(pnm_file
, height_token
);
277 sscanf (height_token
, "%lu", &ul_height
);
278 height
= (png_uint_32
) ul_height
;
279 get_token(pnm_file
, maxval_token
);
280 sscanf (maxval_token
, "%lu", &ul_maxval
);
281 maxval
= (png_uint_32
) ul_maxval
;
284 else if (maxval
<= 3)
286 else if (maxval
<= 15)
288 else if (maxval
<= 255)
290 else /* if (maxval <= 65535) */
298 /* read header of PGM file with alpha channel */
302 if (color_type
== PNG_COLOR_TYPE_GRAY
)
303 color_type
= PNG_COLOR_TYPE_GRAY_ALPHA
;
304 if (color_type
== PNG_COLOR_TYPE_RGB
)
305 color_type
= PNG_COLOR_TYPE_RGB_ALPHA
;
307 get_token(alpha_file
, type_token
);
308 if (type_token
[0] != 'P')
312 else if ((type_token
[1] == '2') || (type_token
[1] == '5'))
314 alpha_raw
= (type_token
[1] == '5');
315 get_token(alpha_file
, width_token
);
316 sscanf (width_token
, "%lu", &ul_alpha_width
);
317 alpha_width
=(png_uint_32
) ul_alpha_width
;
318 if (alpha_width
!= width
)
320 get_token(alpha_file
, height_token
);
321 sscanf (height_token
, "%lu", &ul_alpha_height
);
322 alpha_height
= (png_uint_32
) ul_alpha_height
;
323 if (alpha_height
!= height
)
325 get_token(alpha_file
, maxval_token
);
326 sscanf (maxval_token
, "%lu", &ul_maxval
);
327 maxval
= (png_uint_32
) ul_maxval
;
330 else if (maxval
<= 3)
332 else if (maxval
<= 15)
334 else if (maxval
<= 255)
336 else /* if (maxval <= 65535) */
338 if (alpha_depth
!= bit_depth
)
347 /* calculate the number of channels and store alpha-presence */
348 if (color_type
== PNG_COLOR_TYPE_GRAY
)
350 else if (color_type
== PNG_COLOR_TYPE_GRAY_ALPHA
)
352 else if (color_type
== PNG_COLOR_TYPE_RGB
)
354 else if (color_type
== PNG_COLOR_TYPE_RGB_ALPHA
)
357 channels
= 0; /* should not happen */
359 alpha_present
= (channels
- 1) % 2;
361 #if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
363 /* row data is as many bytes as can fit width x channels x bit_depth */
364 row_bytes
= (width
* channels
* bit_depth
+ 7) / 8;
367 /* row_bytes is the width x number of channels x (bit-depth / 8) */
368 row_bytes
= width
* channels
* ((bit_depth
<= 8) ? 1 : 2);
370 if ((png_pixels
= (png_byte
*) malloc (row_bytes
* height
* sizeof (png_byte
))) == NULL
)
373 /* read data from PNM file */
374 pix_ptr
= png_pixels
;
376 for (row
= 0; row
< height
; row
++)
378 #if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
380 for (i
= 0; i
< row_bytes
; i
++)
381 /* png supports this format natively so no conversion is needed */
382 *pix_ptr
++ = get_data (pnm_file
, 8);
386 for (col
= 0; col
< width
; col
++)
388 for (i
= 0; i
< (channels
- alpha_present
); i
++)
391 *pix_ptr
++ = get_data (pnm_file
, bit_depth
);
394 *pix_ptr
++ = get_value (pnm_file
, bit_depth
);
397 tmp16
= get_value (pnm_file
, bit_depth
);
398 *pix_ptr
= (png_byte
) ((tmp16
>> 8) & 0xFF);
400 *pix_ptr
= (png_byte
) (tmp16
& 0xFF);
405 if (alpha
) /* read alpha-channel from pgm file */
408 *pix_ptr
++ = get_data (alpha_file
, alpha_depth
);
410 if (alpha_depth
<= 8)
411 *pix_ptr
++ = get_value (alpha_file
, bit_depth
);
414 tmp16
= get_value (alpha_file
, bit_depth
);
415 *pix_ptr
++ = (png_byte
) ((tmp16
>> 8) & 0xFF);
416 *pix_ptr
++ = (png_byte
) (tmp16
& 0xFF);
419 } /* if packed_bitmap */
423 /* prepare the standard PNG structures */
424 png_ptr
= png_create_write_struct (PNG_LIBPNG_VER_STRING
, NULL
, NULL
, NULL
);
429 info_ptr
= png_create_info_struct (png_ptr
);
432 png_destroy_write_struct (&png_ptr
, (png_infopp
) NULL
);
436 #if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
437 if (packed_bitmap
== TRUE
)
439 png_set_packing (png_ptr
);
440 png_set_invert_mono (png_ptr
);
444 /* setjmp() must be called in every function that calls a PNG-reading libpng function */
445 if (setjmp (png_jmpbuf(png_ptr
)))
447 png_destroy_write_struct (&png_ptr
, (png_infopp
) NULL
);
451 /* initialize the png structure */
452 png_init_io (png_ptr
, png_file
);
454 /* we're going to write more or less the same PNG as the input file */
455 png_set_IHDR (png_ptr
, info_ptr
, width
, height
, bit_depth
, color_type
,
456 (!interlace
) ? PNG_INTERLACE_NONE
: PNG_INTERLACE_ADAM7
,
457 PNG_COMPRESSION_TYPE_BASE
, PNG_FILTER_TYPE_BASE
);
459 /* write the file header information */
460 png_write_info (png_ptr
, info_ptr
);
462 /* if needed we will allocate memory for an new array of row-pointers */
463 if (row_pointers
== (unsigned char**) NULL
)
465 if ((row_pointers
= (png_byte
**) malloc (height
* sizeof (png_bytep
))) == NULL
)
467 png_destroy_write_struct (&png_ptr
, (png_infopp
) NULL
);
472 /* set the individual row_pointers to point at the correct offsets */
473 for (i
= 0; i
< (height
); i
++)
474 row_pointers
[i
] = png_pixels
+ i
* row_bytes
;
476 /* write out the entire image data in one call */
477 png_write_image (png_ptr
, row_pointers
);
479 /* write the additional chuncks to the PNG file (not really needed) */
480 png_write_end (png_ptr
, info_ptr
);
482 /* clean up after the write, and free any memory allocated */
483 png_destroy_write_struct (&png_ptr
, (png_infopp
) NULL
);
485 if (row_pointers
!= (unsigned char**) NULL
)
487 if (png_pixels
!= (unsigned char*) NULL
)
491 } /* end of pnm2png */
494 * get_token() - gets the first string after whitespace
497 void get_token(FILE *pnm_file
, char *token
)
502 /* remove white-space and comment lines */
505 ret
= fgetc(pnm_file
);
507 /* the rest of this line is a comment */
510 ret
= fgetc(pnm_file
);
512 while ((ret
!= '\n') && (ret
!= '\r') && (ret
!= EOF
));
514 if (ret
== EOF
) break;
515 token
[i
] = (unsigned char) ret
;
517 while ((token
[i
] == '\n') || (token
[i
] == '\r') || (token
[i
] == ' '));
522 ret
= fgetc(pnm_file
);
523 if (ret
== EOF
) break;
525 token
[i
] = (unsigned char) ret
;
527 while ((token
[i
] != '\n') && (token
[i
] != '\r') && (token
[i
] != ' '));
535 * get_data() - takes first byte and converts into next pixel value,
536 * taking as much bits as defined by bit-depth and
537 * using the bit-depth to fill up a byte (0Ah -> AAh)
540 png_uint_32
get_data (FILE *pnm_file
, int depth
)
542 static int bits_left
= 0;
543 static int old_value
= 0;
546 png_uint_32 ret_value
;
549 for (i
= 0; i
< depth
; i
++)
550 mask
= (mask
>> 1) | 0x80;
554 old_value
= fgetc (pnm_file
);
558 ret_value
= old_value
& mask
;
559 for (i
= 1; i
< (8 / depth
); i
++)
560 ret_value
= ret_value
|| (ret_value
>> depth
);
562 old_value
= (old_value
<< depth
) & 0xFF;
569 * get_value() - takes first (numeric) string and converts into number,
570 * using the bit-depth to fill up a byte (0Ah -> AAh)
573 png_uint_32
get_value (FILE *pnm_file
, int depth
)
575 static png_uint_32 mask
= 0;
577 unsigned long ul_ret_value
;
578 png_uint_32 ret_value
;
582 for (i
= 0; i
< depth
; i
++)
583 mask
= (mask
<< 1) | 0x01;
585 get_token (pnm_file
, (char *) token
);
586 sscanf ((const char *) token
, "%lu", &ul_ret_value
);
587 ret_value
= (png_uint_32
) ul_ret_value
;
592 for (i
= 0; i
< (8 / depth
); i
++)
593 ret_value
= (ret_value
<< depth
) || ret_value
;