2 * pnm2png.c --- conversion from PBM/PGM/PPM-file to PNG-file
3 * copyright (C) 1999,2015,2017 by Willem van Schaik <willem at schaik.com>
5 * version 1.0 - 1999.10.15 - First version.
6 * version 1.1 - 2015.07.29 - Fixed leaks (Glenn Randers-Pehrson)
7 * version 1.2 - 2017.04.22 - Add buffer-size check
8 * 1.3 - 2017.08.24 - Fix potential overflow in buffer-size check
9 * (Glenn Randers-Pehrson)
10 * 1.4 - 2017.08.28 - Add PNGMINUS_UNUSED (Christian Hesse)
12 * Permission to use, copy, modify, and distribute this software and
13 * its documentation for any purpose and without fee is hereby granted,
14 * provided that the above copyright notice appear in all copies and
15 * that both that copyright notice and this permission notice appear in
16 * supporting documentation. This software is provided "as is" without
17 * express or implied warranty.
29 #define BOOL unsigned char
35 #define FALSE (BOOL) 0
42 /* to make pnm2png verbose so we can find problems (needs to be before png.h) */
49 /* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */
51 # define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)
54 #ifndef PNGMINUS_UNUSED
55 /* Unused formal parameter warnings are silenced using the following macro
56 * which is expected to have no bad effects on performance (optimizing
57 * compilers will probably remove it entirely).
59 # define PNGMINUS_UNUSED(param) (void)param
63 /* function prototypes */
65 int main (int argc
, char *argv
[]);
67 BOOL
pnm2png (FILE *pnm_file
, FILE *png_file
, FILE *alpha_file
, BOOL interlace
,
69 void get_token(FILE *pnm_file
, char *token
);
70 png_uint_32
get_data (FILE *pnm_file
, int depth
);
71 png_uint_32
get_value (FILE *pnm_file
, int depth
);
77 int main(int argc
, char *argv
[])
82 BOOL interlace
= FALSE
;
86 for (argi
= 1; argi
< argc
; argi
++)
88 if (argv
[argi
][0] == '-')
90 switch (argv
[argi
][1])
98 if ((fp_al
= fopen (argv
[argi
], "rb")) == NULL
)
100 fprintf (stderr
, "PNM2PNG\n");
101 fprintf (stderr
, "Error: alpha-channel file %s does not exist\n",
112 fprintf (stderr
, "PNM2PNG\n");
113 fprintf (stderr
, "Error: unknown option %s\n", argv
[argi
]);
119 else if (fp_rd
== stdin
)
121 if ((fp_rd
= fopen (argv
[argi
], "rb")) == NULL
)
123 fprintf (stderr
, "PNM2PNG\n");
124 fprintf (stderr
, "Error: file %s does not exist\n", argv
[argi
]);
128 else if (fp_wr
== stdout
)
130 if ((fp_wr
= fopen (argv
[argi
], "wb")) == NULL
)
132 fprintf (stderr
, "PNM2PNG\n");
133 fprintf (stderr
, "Error: can not create PNG-file %s\n", argv
[argi
]);
139 fprintf (stderr
, "PNM2PNG\n");
140 fprintf (stderr
, "Error: too many parameters\n");
147 /* set stdin/stdout to binary, we're reading the PNM always! in binary format */
150 setmode (STDIN
, O_BINARY
);
154 setmode (STDOUT
, O_BINARY
);
158 /* call the conversion program itself */
159 if (pnm2png (fp_rd
, fp_wr
, fp_al
, interlace
, alpha
) == FALSE
)
161 fprintf (stderr
, "PNM2PNG\n");
162 fprintf (stderr
, "Error: unsuccessful converting to PNG-image\n");
166 /* close input file */
168 /* close output file */
170 /* close alpha file */
183 fprintf (stderr
, "PNM2PNG\n");
184 fprintf (stderr
, " by Willem van Schaik, 1999\n");
186 fprintf (stderr
, " for Turbo-C and Borland-C compilers\n");
188 fprintf (stderr
, " for Linux (and Unix) compilers\n");
190 fprintf (stderr
, "Usage: pnm2png [options] <file>.<pnm> [<file>.png]\n");
191 fprintf (stderr
, " or: ... | pnm2png [options]\n");
192 fprintf (stderr
, "Options:\n");
193 fprintf (stderr
, " -i[nterlace] write png-file with interlacing on\n");
195 " -a[lpha] <file>.pgm read PNG alpha channel as pgm-file\n");
196 fprintf (stderr
, " -h | -? print this help-information\n");
203 BOOL
pnm2png (FILE *pnm_file
, FILE *png_file
, FILE *alpha_file
, BOOL interlace
,
206 png_struct
*png_ptr
= NULL
;
207 png_info
*info_ptr
= NULL
;
208 png_byte
*png_pixels
= NULL
;
209 png_byte
**row_pointers
= NULL
;
210 png_byte
*pix_ptr
= NULL
;
211 volatile png_uint_32 row_bytes
;
214 char width_token
[16];
215 char height_token
[16];
216 char maxval_token
[16];
217 volatile int color_type
=1;
218 unsigned long ul_width
=0, ul_alpha_width
=0;
219 unsigned long ul_height
=0, ul_alpha_height
=0;
220 unsigned long ul_maxval
=0;
221 volatile png_uint_32 width
=0, height
=0;
222 volatile png_uint_32 alpha_width
=0, alpha_height
=0;
224 volatile int bit_depth
= 0;
229 BOOL raw
, alpha_raw
= FALSE
;
230 #if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
231 BOOL packed_bitmap
= FALSE
;
236 /* read header of PNM file */
238 get_token(pnm_file
, type_token
);
239 if (type_token
[0] != 'P')
243 else if ((type_token
[1] == '1') || (type_token
[1] == '4'))
245 #if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
246 raw
= (type_token
[1] == '4');
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
;
255 packed_bitmap
= TRUE
;
257 fprintf (stderr
, "PNM2PNG built without PNG_WRITE_INVERT_SUPPORTED and \n");
258 fprintf (stderr
, "PNG_WRITE_PACK_SUPPORTED can't read PBM (P1,P4) files\n");
261 else if ((type_token
[1] == '2') || (type_token
[1] == '5'))
263 raw
= (type_token
[1] == '5');
264 color_type
= PNG_COLOR_TYPE_GRAY
;
265 get_token(pnm_file
, width_token
);
266 sscanf (width_token
, "%lu", &ul_width
);
267 width
= (png_uint_32
) ul_width
;
268 get_token(pnm_file
, height_token
);
269 sscanf (height_token
, "%lu", &ul_height
);
270 height
= (png_uint_32
) ul_height
;
271 get_token(pnm_file
, maxval_token
);
272 sscanf (maxval_token
, "%lu", &ul_maxval
);
273 maxval
= (png_uint_32
) ul_maxval
;
277 else if (maxval
<= 3)
279 else if (maxval
<= 15)
281 else if (maxval
<= 255)
283 else /* if (maxval <= 65535) */
286 else if ((type_token
[1] == '3') || (type_token
[1] == '6'))
288 raw
= (type_token
[1] == '6');
289 color_type
= PNG_COLOR_TYPE_RGB
;
290 get_token(pnm_file
, width_token
);
291 sscanf (width_token
, "%lu", &ul_width
);
292 width
= (png_uint_32
) ul_width
;
293 get_token(pnm_file
, height_token
);
294 sscanf (height_token
, "%lu", &ul_height
);
295 height
= (png_uint_32
) ul_height
;
296 get_token(pnm_file
, maxval_token
);
297 sscanf (maxval_token
, "%lu", &ul_maxval
);
298 maxval
= (png_uint_32
) ul_maxval
;
301 else if (maxval
<= 3)
303 else if (maxval
<= 15)
305 else if (maxval
<= 255)
307 else /* if (maxval <= 65535) */
315 /* read header of PGM file with alpha channel */
319 if (color_type
== PNG_COLOR_TYPE_GRAY
)
320 color_type
= PNG_COLOR_TYPE_GRAY_ALPHA
;
321 if (color_type
== PNG_COLOR_TYPE_RGB
)
322 color_type
= PNG_COLOR_TYPE_RGB_ALPHA
;
324 get_token(alpha_file
, type_token
);
325 if (type_token
[0] != 'P')
329 else if ((type_token
[1] == '2') || (type_token
[1] == '5'))
331 alpha_raw
= (type_token
[1] == '5');
332 get_token(alpha_file
, width_token
);
333 sscanf (width_token
, "%lu", &ul_alpha_width
);
334 alpha_width
=(png_uint_32
) ul_alpha_width
;
335 if (alpha_width
!= width
)
337 get_token(alpha_file
, height_token
);
338 sscanf (height_token
, "%lu", &ul_alpha_height
);
339 alpha_height
= (png_uint_32
) ul_alpha_height
;
340 if (alpha_height
!= height
)
342 get_token(alpha_file
, maxval_token
);
343 sscanf (maxval_token
, "%lu", &ul_maxval
);
344 maxval
= (png_uint_32
) ul_maxval
;
347 else if (maxval
<= 3)
349 else if (maxval
<= 15)
351 else if (maxval
<= 255)
353 else /* if (maxval <= 65535) */
355 if (alpha_depth
!= bit_depth
)
364 /* calculate the number of channels and store alpha-presence */
365 if (color_type
== PNG_COLOR_TYPE_GRAY
)
367 else if (color_type
== PNG_COLOR_TYPE_GRAY_ALPHA
)
369 else if (color_type
== PNG_COLOR_TYPE_RGB
)
371 else if (color_type
== PNG_COLOR_TYPE_RGB_ALPHA
)
375 channels
= 0; /* cannot happen */
378 alpha_present
= (channels
- 1) % 2;
380 #if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
382 /* row data is as many bytes as can fit width x channels x bit_depth */
383 row_bytes
= (width
* channels
* bit_depth
+ 7) / 8;
386 /* row_bytes is the width x number of channels x (bit-depth / 8) */
387 row_bytes
= width
* channels
* ((bit_depth
<= 8) ? 1 : 2);
389 if ((row_bytes
== 0 || (size_t)height
> ((size_t)(-1))/(size_t)row_bytes
))
394 if ((png_pixels
= (png_byte
*)
395 malloc ((size_t)row_bytes
* (size_t)height
* sizeof (png_byte
))) == NULL
)
398 /* read data from PNM file */
399 pix_ptr
= png_pixels
;
401 for (row
= 0; row
< (int) height
; row
++)
403 #if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
406 for (i
= 0; i
< (int) row_bytes
; i
++)
407 /* png supports this format natively so no conversion is needed */
408 *pix_ptr
++ = get_data (pnm_file
, 8);
412 for (col
= 0; col
< (int) width
; col
++)
414 for (i
= 0; i
< (channels
- alpha_present
); i
++)
417 *pix_ptr
++ = get_data (pnm_file
, bit_depth
);
420 *pix_ptr
++ = get_value (pnm_file
, bit_depth
);
423 tmp16
= get_value (pnm_file
, bit_depth
);
424 *pix_ptr
= (png_byte
) ((tmp16
>> 8) & 0xFF);
426 *pix_ptr
= (png_byte
) (tmp16
& 0xFF);
431 if (alpha
) /* read alpha-channel from pgm file */
434 *pix_ptr
++ = get_data (alpha_file
, alpha_depth
);
436 if (alpha_depth
<= 8)
437 *pix_ptr
++ = get_value (alpha_file
, bit_depth
);
440 tmp16
= get_value (alpha_file
, bit_depth
);
441 *pix_ptr
++ = (png_byte
) ((tmp16
>> 8) & 0xFF);
442 *pix_ptr
++ = (png_byte
) (tmp16
& 0xFF);
445 } /* if packed_bitmap */
449 /* prepare the standard PNG structures */
450 png_ptr
= png_create_write_struct (png_get_libpng_ver(NULL
), NULL
, NULL
,
458 info_ptr
= png_create_info_struct (png_ptr
);
461 png_destroy_write_struct (&png_ptr
, (png_infopp
) NULL
);
467 #if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
468 if (packed_bitmap
== TRUE
)
470 png_set_packing (png_ptr
);
471 png_set_invert_mono (png_ptr
);
475 /* setjmp() must be called in every function that calls a PNG-reading libpng function */
476 if (setjmp (png_jmpbuf(png_ptr
)))
478 png_destroy_write_struct (&png_ptr
, &info_ptr
);
484 /* initialize the png structure */
485 png_init_io (png_ptr
, png_file
);
487 /* we're going to write more or less the same PNG as the input file */
488 png_set_IHDR (png_ptr
, info_ptr
, width
, height
, bit_depth
, color_type
,
489 (!interlace
) ? PNG_INTERLACE_NONE
: PNG_INTERLACE_ADAM7
,
490 PNG_COMPRESSION_TYPE_BASE
, PNG_FILTER_TYPE_BASE
);
492 /* write the file header information */
493 png_write_info (png_ptr
, info_ptr
);
495 /* if needed we will allocate memory for an new array of row-pointers */
496 if (row_pointers
== (unsigned char**) NULL
)
498 if ((row_pointers
= (png_byte
**)
499 malloc (height
* sizeof (png_bytep
))) == NULL
)
501 png_destroy_write_struct (&png_ptr
, &info_ptr
);
508 /* set the individual row_pointers to point at the correct offsets */
509 for (i
= 0; i
< (int) height
; i
++)
510 row_pointers
[i
] = png_pixels
+ i
* row_bytes
;
512 /* write out the entire image data in one call */
513 png_write_image (png_ptr
, row_pointers
);
515 /* write the additional chunks to the PNG file (not really needed) */
516 png_write_end (png_ptr
, info_ptr
);
518 /* clean up after the write, and free any memory allocated */
519 png_destroy_write_struct (&png_ptr
, &info_ptr
);
521 if (row_pointers
!= (unsigned char**) NULL
)
523 if (png_pixels
!= (unsigned char*) NULL
)
526 PNGMINUS_UNUSED(raw
); /* Quiet a Coverity defect */
529 } /* end of pnm2png */
532 * get_token() - gets the first string after whitespace
535 void get_token(FILE *pnm_file
, char *token
)
540 /* remove white-space and comment lines */
543 ret
= fgetc(pnm_file
);
546 /* the rest of this line is a comment */
549 ret
= fgetc(pnm_file
);
551 while ((ret
!= '\n') && (ret
!= '\r') && (ret
!= EOF
));
553 if (ret
== EOF
) break;
554 token
[i
] = (unsigned char) ret
;
556 while ((token
[i
] == '\n') || (token
[i
] == '\r') || (token
[i
] == ' '));
561 ret
= fgetc(pnm_file
);
562 if (ret
== EOF
) break;
564 token
[i
] = (unsigned char) ret
;
566 while ((token
[i
] != '\n') && (token
[i
] != '\r') && (token
[i
] != ' '));
574 * get_data() - takes first byte and converts into next pixel value,
575 * taking as much bits as defined by bit-depth and
576 * using the bit-depth to fill up a byte (0Ah -> AAh)
579 png_uint_32
get_data (FILE *pnm_file
, int depth
)
581 static int bits_left
= 0;
582 static int old_value
= 0;
585 png_uint_32 ret_value
;
588 for (i
= 0; i
< depth
; i
++)
589 mask
= (mask
>> 1) | 0x80;
593 old_value
= fgetc (pnm_file
);
597 ret_value
= old_value
& mask
;
598 for (i
= 1; i
< (8 / depth
); i
++)
599 ret_value
= ret_value
|| (ret_value
>> depth
);
601 old_value
= (old_value
<< depth
) & 0xFF;
608 * get_value() - takes first (numeric) string and converts into number,
609 * using the bit-depth to fill up a byte (0Ah -> AAh)
612 png_uint_32
get_value (FILE *pnm_file
, int depth
)
614 static png_uint_32 mask
= 0;
616 unsigned long ul_ret_value
;
617 png_uint_32 ret_value
;
621 for (i
= 0; i
< depth
; i
++)
622 mask
= (mask
<< 1) | 0x01;
624 get_token (pnm_file
, (char *) token
);
625 sscanf ((const char *) token
, "%lu", &ul_ret_value
);
626 ret_value
= (png_uint_32
) ul_ret_value
;
631 for (i
= 0; i
< (8 / depth
); i
++)
632 ret_value
= (ret_value
<< depth
) || ret_value
;