png2pnm.c@ 76030

Last change on this file since 76030 was 76030, checked in by vboxsync, 6 years ago
libpng-1.6.36: properly export to OSE, and while at it fix EOL style for shell scripts
Property svn:eol-style set to `native`
File size: 12.2 KB

Line
1	/*
2	* png2pnm.c --- conversion from PNG-file to PGM/PPM-file
3	* copyright (C) 1999,2017 by Willem van Schaik <willem at schaik.com>
4	*
5	* version 1.0 - 1999.10.15 - First version.
6	* 1.1 - 2017.04.22 - Add buffer-size check (Glenn Randers-Pehrson)
7	* 1.2 - 2017.08.24 - Fix potential overflow in buffer-size check
8	* (Glenn Randers-Pehrson)
9	* 1.3 - 2017.08.28 - Add PNGMINUS_UNUSED (Christian Hesse)
10	*
11	* Permission to use, copy, modify, and distribute this software and
12	* its documentation for any purpose and without fee is hereby granted,
13	* provided that the above copyright notice appear in all copies and
14	* that both that copyright notice and this permission notice appear in
15	* supporting documentation. This software is provided "as is" without
16	* express or implied warranty.
17	*/
18
19	#include <stdio.h>
20	#include <stdlib.h>
21	#ifdef __TURBOC__
22	#include <mem.h>
23	#include <fcntl.h>
24	#endif
25	#include <zlib.h>
26
27	#ifndef BOOL
28	#define BOOL unsigned char
29	#endif
30	#ifndef TRUE
31	#define TRUE (BOOL) 1
32	#endif
33	#ifndef FALSE
34	#define FALSE (BOOL) 0
35	#endif
36
37	#ifdef __TURBOC__
38	#define STDIN 0
39	#define STDOUT 1
40	#define STDERR 2
41	#endif
42
43	/* to make png2pnm verbose so we can find problems (needs to be before png.h) */
44	#ifndef PNG_DEBUG
45	#define PNG_DEBUG 0
46	#endif
47
48
49	#include "png.h"
50
51	/* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */
52	#ifndef png_jmpbuf
53	# define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)
54	#endif
55
56	#ifndef PNGMINUS_UNUSED
57	/* Unused formal parameter warnings are silenced using the following macro
58	* which is expected to have no bad effects on performance (optimizing
59	* compilers will probably remove it entirely).
60	*/
61	# define PNGMINUS_UNUSED(param) (void)param
62	#endif
63
64	/* function prototypes */
65
66	int main (int argc, char *argv[]);
67	void usage ();
68	BOOL png2pnm (FILE png_file, FILE pnm_file, FILE *alpha_file, BOOL raw,
69	BOOL alpha);
70
71	/*
72	* main
73	*/
74
75	int main(int argc, char *argv[])
76	{
77	FILE *fp_rd = stdin;
78	FILE *fp_wr = stdout;
79	FILE *fp_al = NULL;
80	BOOL raw = TRUE;
81	BOOL alpha = FALSE;
82	int argi;
83
84	for (argi = 1; argi < argc; argi++)
85	{
86	if (argv[argi][0] == '-')
87	{
88	switch (argv[argi][1])
89	{
90	case 'n':
91	raw = FALSE;
92	break;
93	case 'r':
94	raw = TRUE;
95	break;
96	case 'a':
97	alpha = TRUE;
98	argi++;
99	if ((fp_al = fopen (argv[argi], "wb")) == NULL)
100	{
101	fprintf (stderr, "PNM2PNG\n");
102	fprintf (stderr, "Error: can not create alpha-channel file %s\n",
103	argv[argi]);
104	exit (1);
105	}
106	break;
107	case 'h':
108	case '?':
109	usage();
110	exit(0);
111	break;
112	default:
113	fprintf (stderr, "PNG2PNM\n");
114	fprintf (stderr, "Error: unknown option %s\n", argv[argi]);
115	usage();
116	exit(1);
117	break;
118	} /* end switch */
119	}
120	else if (fp_rd == stdin)
121	{
122	if ((fp_rd = fopen (argv[argi], "rb")) == NULL)
123	{
124	fprintf (stderr, "PNG2PNM\n");
125	fprintf (stderr, "Error: file %s does not exist\n", argv[argi]);
126	exit (1);
127	}
128	}
129	else if (fp_wr == stdout)
130	{
131	if ((fp_wr = fopen (argv[argi], "wb")) == NULL)
132	{
133	fprintf (stderr, "PNG2PNM\n");
134	fprintf (stderr, "Error: can not create file %s\n", argv[argi]);
135	exit (1);
136	}
137	}
138	else
139	{
140	fprintf (stderr, "PNG2PNM\n");
141	fprintf (stderr, "Error: too many parameters\n");
142	usage();
143	exit(1);
144	}
145	} /* end for */
146
147	#ifdef __TURBOC__
148	/* set stdin/stdout if required to binary */
149	if (fp_rd == stdin)
150	{
151	setmode (STDIN, O_BINARY);
152	}
153	if ((raw) && (fp_wr == stdout))
154	{
155	setmode (STDOUT, O_BINARY);
156	}
157	#endif
158
159	/* call the conversion program itself */
160	if (png2pnm (fp_rd, fp_wr, fp_al, raw, alpha) == FALSE)
161	{
162	fprintf (stderr, "PNG2PNM\n");
163	fprintf (stderr, "Error: unsuccessful conversion of PNG-image\n");
164	exit(1);
165	}
166
167	/* close input file */
168	fclose (fp_rd);
169	/* close output file */
170	fclose (fp_wr);
171	/* close alpha file */
172	if (alpha)
173	fclose (fp_al);
174
175	return 0;
176	}
177
178	/*
179	* usage
180	*/
181
182	void usage()
183	{
184	fprintf (stderr, "PNG2PNM\n");
185	fprintf (stderr, " by Willem van Schaik, 1999\n");
186	#ifdef __TURBOC__
187	fprintf (stderr, " for Turbo-C and Borland-C compilers\n");
188	#else
189	fprintf (stderr, " for Linux (and Unix) compilers\n");
190	#endif
191	fprintf (stderr, "Usage: png2pnm [options] <file>.png [<file>.pnm]\n");
192	fprintf (stderr, " or: ... \| png2pnm [options]\n");
193	fprintf (stderr, "Options:\n");
194	fprintf (stderr,
195	" -r[aw] write pnm-file in binary format (P4/P5/P6) (default)\n");
196	fprintf (stderr, " -n[oraw] write pnm-file in ascii format (P1/P2/P3)\n");
197	fprintf (stderr,
198	" -a[lpha] <file>.pgm write PNG alpha channel as pgm-file\n");
199	fprintf (stderr, " -h \| -? print this help-information\n");
200	}
201
202	/*
203	* png2pnm
204	*/
205
206	BOOL png2pnm (FILE png_file, FILE pnm_file, FILE *alpha_file,
207	volatile BOOL raw, BOOL alpha)
208	{
209	png_struct *png_ptr = NULL;
210	png_info *info_ptr = NULL;
211	png_byte buf[8];
212	png_byte *png_pixels = NULL;
213	png_byte **row_pointers = NULL;
214	png_byte *pix_ptr = NULL;
215	png_uint_32 row_bytes;
216
217	png_uint_32 width;
218	png_uint_32 height;
219	int bit_depth;
220	int channels;
221	int color_type;
222	int alpha_present;
223	int row, col;
224	int ret;
225	int i;
226	long dep_16;
227
228	/* read and check signature in PNG file */
229	ret = fread (buf, 1, 8, png_file);
230	if (ret != 8)
231	return FALSE;
232
233	ret = png_sig_cmp (buf, 0, 8);
234	if (ret)
235	return FALSE;
236
237	/* create png and info structures */
238
239	png_ptr = png_create_read_struct (png_get_libpng_ver(NULL),
240	NULL, NULL, NULL);
241	if (!png_ptr)
242	return FALSE; /* out of memory */
243
244	info_ptr = png_create_info_struct (png_ptr);
245	if (!info_ptr)
246	{
247	png_destroy_read_struct (&png_ptr, NULL, NULL);
248	return FALSE; /* out of memory */
249	}
250
251	if (setjmp (png_jmpbuf(png_ptr)))
252	{
253	png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
254	return FALSE;
255	}
256
257	/* set up the input control for C streams */
258	png_init_io (png_ptr, png_file);
259	png_set_sig_bytes (png_ptr, 8); /* we already read the 8 signature bytes */
260
261	/* read the file information */
262	png_read_info (png_ptr, info_ptr);
263
264	/* get size and bit-depth of the PNG-image */
265	png_get_IHDR (png_ptr, info_ptr,
266	&width, &height, &bit_depth, &color_type,
267	NULL, NULL, NULL);
268
269	/* set-up the transformations */
270
271	/* transform paletted images into full-color rgb */
272	if (color_type == PNG_COLOR_TYPE_PALETTE)
273	png_set_expand (png_ptr);
274	/* expand images to bit-depth 8 (only applicable for grayscale images) */
275	if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
276	png_set_expand (png_ptr);
277	/* transform transparency maps into full alpha-channel */
278	if (png_get_valid (png_ptr, info_ptr, PNG_INFO_tRNS))
279	png_set_expand (png_ptr);
280
281	#ifdef NJET
282	/* downgrade 16-bit images to 8-bit */
283	if (bit_depth == 16)
284	png_set_strip_16 (png_ptr);
285	/* transform grayscale images into full-color */
286	if (color_type == PNG_COLOR_TYPE_GRAY \|\|
287	color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
288	png_set_gray_to_rgb (png_ptr);
289	/* only if file has a file gamma, we do a correction */
290	if (png_get_gAMA (png_ptr, info_ptr, &file_gamma))
291	png_set_gamma (png_ptr, (double) 2.2, file_gamma);
292	#endif
293
294	/* all transformations have been registered; now update info_ptr data,
295	* get rowbytes and channels, and allocate image memory */
296
297	png_read_update_info (png_ptr, info_ptr);
298
299	/* get the new color-type and bit-depth (after expansion/stripping) */
300	png_get_IHDR (png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
301	NULL, NULL, NULL);
302
303	/* check for 16-bit files */
304	if (bit_depth == 16)
305	{
306	raw = FALSE;
307	#ifdef __TURBOC__
308	pnm_file->flags &= ~((unsigned) _F_BIN);
309	#endif
310	}
311
312	/* calculate new number of channels and store alpha-presence */
313	if (color_type == PNG_COLOR_TYPE_GRAY)
314	channels = 1;
315	else if (color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
316	channels = 2;
317	else if (color_type == PNG_COLOR_TYPE_RGB)
318	channels = 3;
319	else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
320	channels = 4;
321	else
322	channels = 0; /* should never happen */
323	alpha_present = (channels - 1) % 2;
324
325	/* check if alpha is expected to be present in file */
326	if (alpha && !alpha_present)
327	{
328	fprintf (stderr, "PNG2PNM\n");
329	fprintf (stderr, "Error: PNG-file doesn't contain alpha channel\n");
330	exit (1);
331	}
332
333	/* row_bytes is the width x number of channels x (bit-depth / 8) */
334	row_bytes = png_get_rowbytes (png_ptr, info_ptr);
335
336	if ((row_bytes == 0 \|\| (size_t)height > ((size_t)(-1))/(size_t)row_bytes))
337	{
338	/* too big */
339	png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
340	return FALSE;
341	}
342	if ((png_pixels = (png_byte *)
343	malloc ((size_t)row_bytes * (size_t)height * sizeof (png_byte))) == NULL)
344	{
345	png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
346	return FALSE;
347	}
348
349	if ((row_pointers = (png_byte **)
350	malloc ((size_t)height * sizeof (png_bytep))) == NULL)
351	{
352	png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
353	free (png_pixels);
354	png_pixels = NULL;
355	return FALSE;
356	}
357
358	/* set the individual row_pointers to point at the correct offsets */
359	for (i = 0; i < ((int) height); i++)
360	row_pointers[i] = png_pixels + i * row_bytes;
361
362	/* now we can go ahead and just read the whole image */
363	png_read_image (png_ptr, row_pointers);
364
365	/* read rest of file, and get additional chunks in info_ptr - REQUIRED */
366	png_read_end (png_ptr, info_ptr);
367
368	/* clean up after the read, and free any memory allocated - REQUIRED */
369	png_destroy_read_struct (&png_ptr, &info_ptr, (png_infopp) NULL);
370
371	/* write header of PNM file */
372
373	if ((color_type == PNG_COLOR_TYPE_GRAY) \|\|
374	(color_type == PNG_COLOR_TYPE_GRAY_ALPHA))
375	{
376	fprintf (pnm_file, "%s\n", (raw) ? "P5" : "P2");
377	fprintf (pnm_file, "%d %d\n", (int) width, (int) height);
378	fprintf (pnm_file, "%ld\n", ((1L << (int) bit_depth) - 1L));
379	}
380	else if ((color_type == PNG_COLOR_TYPE_RGB) \|\|
381	(color_type == PNG_COLOR_TYPE_RGB_ALPHA))
382	{
383	fprintf (pnm_file, "%s\n", (raw) ? "P6" : "P3");
384	fprintf (pnm_file, "%d %d\n", (int) width, (int) height);
385	fprintf (pnm_file, "%ld\n", ((1L << (int) bit_depth) - 1L));
386	}
387
388	/* write header of PGM file with alpha channel */
389
390	if ((alpha) &&
391	((color_type == PNG_COLOR_TYPE_GRAY_ALPHA) \|\|
392	(color_type == PNG_COLOR_TYPE_RGB_ALPHA)))
393	{
394	fprintf (alpha_file, "%s\n", (raw) ? "P5" : "P2");
395	fprintf (alpha_file, "%d %d\n", (int) width, (int) height);
396	fprintf (alpha_file, "%ld\n", ((1L << (int) bit_depth) - 1L));
397	}
398
399	/* write data to PNM file */
400	pix_ptr = png_pixels;
401
402	for (row = 0; row < (int) height; row++)
403	{
404	for (col = 0; col < (int) width; col++)
405	{
406	for (i = 0; i < (channels - alpha_present); i++)
407	{
408	if (raw)
409	fputc ((int) *pix_ptr++ , pnm_file);
410	else
411	if (bit_depth == 16){
412	dep_16 = (long) *pix_ptr++;
413	fprintf (pnm_file, "%ld ", (dep_16 << 8) + ((long) *pix_ptr++));
414	}
415	else
416	fprintf (pnm_file, "%ld ", (long) *pix_ptr++);
417	}
418	if (alpha_present)
419	{
420	if (!alpha)
421	{
422	pix_ptr++; /* alpha */
423	if (bit_depth == 16)
424	pix_ptr++;
425	}
426	else /* output alpha-channel as pgm file */
427	{
428	if (raw)
429	fputc ((int) *pix_ptr++ , alpha_file);
430	else
431	if (bit_depth == 16)
432	{
433	dep_16 = (long) *pix_ptr++;
434	fprintf (alpha_file, "%ld ", (dep_16 << 8) + (long) *pix_ptr++);
435	}
436	else
437	fprintf (alpha_file, "%ld ", (long) *pix_ptr++);
438	}
439	} /* if alpha_present */
440
441	if (!raw)
442	if (col % 4 == 3)
443	fprintf (pnm_file, "\n");
444	} /* end for col */
445
446	if (!raw)
447	if (col % 4 != 0)
448	fprintf (pnm_file, "\n");
449	} /* end for row */
450
451	if (row_pointers != (unsigned char**) NULL)
452	free (row_pointers);
453	if (png_pixels != (unsigned char*) NULL)
454	free (png_pixels);
455
456	PNGMINUS_UNUSED(raw); /* to quiet a Coverity defect */
457	return TRUE;
458
459	} /* end of source */
460

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source: vbox/trunk/src/libs/libpng-1.6.36/contrib/pngminus/png2pnm.c@ 76030

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