Libav
pnm.c
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1 /*
2  * PNM image format
3  * Copyright (c) 2002, 2003 Fabrice Bellard
4  *
5  * This file is part of Libav.
6  *
7  * Libav is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * Libav is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include <stdlib.h>
23 #include <string.h>
24 
25 #include "libavutil/imgutils.h"
26 #include "avcodec.h"
27 #include "pnm.h"
28 
29 static inline int pnm_space(int c)
30 {
31  return c == ' ' || c == '\n' || c == '\r' || c == '\t';
32 }
33 
34 static void pnm_get(PNMContext *sc, char *str, int buf_size)
35 {
36  char *s;
37  int c;
38 
39  /* skip spaces and comments */
40  for (;;) {
41  c = *sc->bytestream++;
42  if (c == '#') {
43  do {
44  c = *sc->bytestream++;
45  } while (c != '\n' && sc->bytestream < sc->bytestream_end);
46  } else if (!pnm_space(c)) {
47  break;
48  }
49  }
50 
51  s = str;
52  while (sc->bytestream < sc->bytestream_end && !pnm_space(c)) {
53  if ((s - str) < buf_size - 1)
54  *s++ = c;
55  c = *sc->bytestream++;
56  }
57  *s = '\0';
58 }
59 
61 {
62  char buf1[32], tuple_type[32];
63  int h, w, depth, maxval;
64 
65  pnm_get(s, buf1, sizeof(buf1));
66  s->type= buf1[1]-'0';
67  if(buf1[0] != 'P')
68  return AVERROR_INVALIDDATA;
69 
70  if (s->type==1 || s->type==4) {
72  } else if (s->type==2 || s->type==5) {
73  if (avctx->codec_id == AV_CODEC_ID_PGMYUV)
74  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
75  else
76  avctx->pix_fmt = AV_PIX_FMT_GRAY8;
77  } else if (s->type==3 || s->type==6) {
78  avctx->pix_fmt = AV_PIX_FMT_RGB24;
79  } else if (s->type==7) {
80  w = -1;
81  h = -1;
82  maxval = -1;
83  depth = -1;
84  tuple_type[0] = '\0';
85  for (;;) {
86  pnm_get(s, buf1, sizeof(buf1));
87  if (!strcmp(buf1, "WIDTH")) {
88  pnm_get(s, buf1, sizeof(buf1));
89  w = strtol(buf1, NULL, 10);
90  } else if (!strcmp(buf1, "HEIGHT")) {
91  pnm_get(s, buf1, sizeof(buf1));
92  h = strtol(buf1, NULL, 10);
93  } else if (!strcmp(buf1, "DEPTH")) {
94  pnm_get(s, buf1, sizeof(buf1));
95  depth = strtol(buf1, NULL, 10);
96  } else if (!strcmp(buf1, "MAXVAL")) {
97  pnm_get(s, buf1, sizeof(buf1));
98  maxval = strtol(buf1, NULL, 10);
99  } else if (!strcmp(buf1, "TUPLTYPE") ||
100  /* libavcodec used to write invalid files */
101  !strcmp(buf1, "TUPLETYPE")) {
102  pnm_get(s, tuple_type, sizeof(tuple_type));
103  } else if (!strcmp(buf1, "ENDHDR")) {
104  break;
105  } else {
106  return AVERROR_INVALIDDATA;
107  }
108  }
109  /* check that all tags are present */
110  if (w <= 0 || h <= 0 || maxval <= 0 || depth <= 0 || tuple_type[0] == '\0' || av_image_check_size(w, h, 0, avctx))
111  return AVERROR_INVALIDDATA;
112 
113  avctx->width = w;
114  avctx->height = h;
115  if (depth == 1) {
116  if (maxval == 1)
117  avctx->pix_fmt = AV_PIX_FMT_MONOWHITE;
118  else
119  avctx->pix_fmt = AV_PIX_FMT_GRAY8;
120  } else if (depth == 3) {
121  if (maxval < 256) {
122  avctx->pix_fmt = AV_PIX_FMT_RGB24;
123  } else {
124  av_log(avctx, AV_LOG_ERROR, "16-bit components are only supported for grayscale\n");
125  avctx->pix_fmt = AV_PIX_FMT_NONE;
126  return AVERROR_INVALIDDATA;
127  }
128  } else if (depth == 4) {
129  avctx->pix_fmt = AV_PIX_FMT_RGB32;
130  } else {
131  return AVERROR_INVALIDDATA;
132  }
133  return 0;
134  } else {
135  return AVERROR_INVALIDDATA;
136  }
137  pnm_get(s, buf1, sizeof(buf1));
138  avctx->width = atoi(buf1);
139  if (avctx->width <= 0)
140  return AVERROR_INVALIDDATA;
141  pnm_get(s, buf1, sizeof(buf1));
142  avctx->height = atoi(buf1);
143  if(av_image_check_size(avctx->width, avctx->height, 0, avctx))
144  return AVERROR_INVALIDDATA;
145  if (avctx->pix_fmt != AV_PIX_FMT_MONOWHITE) {
146  pnm_get(s, buf1, sizeof(buf1));
147  s->maxval = atoi(buf1);
148  if (s->maxval <= 0) {
149  av_log(avctx, AV_LOG_ERROR, "Invalid maxval: %d\n", s->maxval);
150  s->maxval = 255;
151  }
152  if (s->maxval >= 256) {
153  if (avctx->pix_fmt == AV_PIX_FMT_GRAY8) {
154  avctx->pix_fmt = AV_PIX_FMT_GRAY16BE;
155  if (s->maxval != 65535)
156  avctx->pix_fmt = AV_PIX_FMT_GRAY16;
157  } else if (avctx->pix_fmt == AV_PIX_FMT_RGB24) {
158  if (s->maxval > 255)
159  avctx->pix_fmt = AV_PIX_FMT_RGB48BE;
160  } else if (avctx->pix_fmt == AV_PIX_FMT_YUV420P && s->maxval < 65536) {
161  if (s->maxval < 512)
163  else if (s->maxval < 1024)
165  else
166  avctx->pix_fmt = AV_PIX_FMT_YUV420P16;
167  } else {
168  av_log(avctx, AV_LOG_ERROR, "Unsupported pixel format\n");
169  avctx->pix_fmt = AV_PIX_FMT_NONE;
170  return AVERROR_INVALIDDATA;
171  }
172  }
173  }else
174  s->maxval=1;
175  /* more check if YUV420 */
177  if ((avctx->width & 1) != 0)
178  return AVERROR_INVALIDDATA;
179  h = (avctx->height * 2);
180  if ((h % 3) != 0)
181  return AVERROR_INVALIDDATA;
182  h /= 3;
183  avctx->height = h;
184  }
185  return 0;
186 }