FFmpeg
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 FFmpeg.
6  *
7  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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/avassert.h"
26 #include "libavutil/imgutils.h"
27 #include "libavutil/avstring.h"
28 #include "avcodec.h"
29 #include "internal.h"
30 #include "pnm.h"
31 
32 static inline int pnm_space(int c)
33 {
34  return c == ' ' || c == '\n' || c == '\r' || c == '\t';
35 }
36 
37 static void pnm_get(PNMContext *sc, char *str, int buf_size)
38 {
39  char *s;
40  int c;
41  uint8_t *bs = sc->bytestream;
42  const uint8_t *end = sc->bytestream_end;
43 
44  /* skip spaces and comments */
45  while (bs < end) {
46  c = *bs++;
47  if (c == '#') {
48  while (c != '\n' && bs < end) {
49  c = *bs++;
50  }
51  } else if (!pnm_space(c)) {
52  break;
53  }
54  }
55 
56  s = str;
57  while (bs < end && !pnm_space(c) && (s - str) < buf_size - 1) {
58  *s++ = c;
59  c = *bs++;
60  }
61  *s = '\0';
62  sc->bytestream = bs;
63 }
64 
66 {
67  char buf1[32], tuple_type[32];
68  int h, w, depth, maxval;
69  int ret;
70 
71  if (s->bytestream_end - s->bytestream < 3 ||
72  s->bytestream[0] != 'P' ||
73  (s->bytestream[1] < '1' ||
74  s->bytestream[1] > '7' &&
75  s->bytestream[1] != 'F')) {
76  s->bytestream += s->bytestream_end > s->bytestream;
77  s->bytestream += s->bytestream_end > s->bytestream;
78  return AVERROR_INVALIDDATA;
79  }
80  pnm_get(s, buf1, sizeof(buf1));
81  s->type= buf1[1]-'0';
82 
83  if (buf1[1] == 'F') {
84  avctx->pix_fmt = AV_PIX_FMT_GBRPF32;
85  } else if (s->type==1 || s->type==4) {
87  } else if (s->type==2 || s->type==5) {
88  if (avctx->codec_id == AV_CODEC_ID_PGMYUV)
89  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
90  else
91  avctx->pix_fmt = AV_PIX_FMT_GRAY8;
92  } else if (s->type==3 || s->type==6) {
93  avctx->pix_fmt = AV_PIX_FMT_RGB24;
94  } else if (s->type==7) {
95  w = -1;
96  h = -1;
97  maxval = -1;
98  depth = -1;
99  tuple_type[0] = '\0';
100  for (;;) {
101  pnm_get(s, buf1, sizeof(buf1));
102  if (!strcmp(buf1, "WIDTH")) {
103  pnm_get(s, buf1, sizeof(buf1));
104  w = strtol(buf1, NULL, 10);
105  } else if (!strcmp(buf1, "HEIGHT")) {
106  pnm_get(s, buf1, sizeof(buf1));
107  h = strtol(buf1, NULL, 10);
108  } else if (!strcmp(buf1, "DEPTH")) {
109  pnm_get(s, buf1, sizeof(buf1));
110  depth = strtol(buf1, NULL, 10);
111  } else if (!strcmp(buf1, "MAXVAL")) {
112  pnm_get(s, buf1, sizeof(buf1));
113  maxval = strtol(buf1, NULL, 10);
114  } else if (!strcmp(buf1, "TUPLTYPE") ||
115  /* libavcodec used to write invalid files */
116  !strcmp(buf1, "TUPLETYPE")) {
117  pnm_get(s, tuple_type, sizeof(tuple_type));
118  } else if (!strcmp(buf1, "ENDHDR")) {
119  break;
120  } else {
121  return AVERROR_INVALIDDATA;
122  }
123  }
124  if (!pnm_space(s->bytestream[-1]))
125  return AVERROR_INVALIDDATA;
126 
127  /* check that all tags are present */
128  if (w <= 0 || h <= 0 || maxval <= 0 || maxval > UINT16_MAX || depth <= 0 || tuple_type[0] == '\0' ||
129  av_image_check_size(w, h, 0, avctx) || s->bytestream >= s->bytestream_end)
130  return AVERROR_INVALIDDATA;
131 
132  ret = ff_set_dimensions(avctx, w, h);
133  if (ret < 0)
134  return ret;
135  s->maxval = maxval;
136  if (depth == 1) {
137  if (maxval == 1) {
138  avctx->pix_fmt = AV_PIX_FMT_MONOBLACK;
139  } else if (maxval < 256) {
140  avctx->pix_fmt = AV_PIX_FMT_GRAY8;
141  } else {
142  avctx->pix_fmt = AV_PIX_FMT_GRAY16;
143  }
144  } else if (depth == 2) {
145  if (maxval < 256) {
146  avctx->pix_fmt = AV_PIX_FMT_GRAY8A;
147  } else {
148  avctx->pix_fmt = AV_PIX_FMT_YA16;
149  }
150  } else if (depth == 3) {
151  if (maxval < 256) {
152  avctx->pix_fmt = AV_PIX_FMT_RGB24;
153  } else {
154  avctx->pix_fmt = AV_PIX_FMT_RGB48;
155  }
156  } else if (depth == 4) {
157  if (maxval < 256) {
158  avctx->pix_fmt = AV_PIX_FMT_RGBA;
159  } else {
160  avctx->pix_fmt = AV_PIX_FMT_RGBA64;
161  }
162  } else {
163  return AVERROR_INVALIDDATA;
164  }
165  return 0;
166  } else {
167  av_assert0(0);
168  }
169  pnm_get(s, buf1, sizeof(buf1));
170  w = atoi(buf1);
171  pnm_get(s, buf1, sizeof(buf1));
172  h = atoi(buf1);
173  if(w <= 0 || h <= 0 || av_image_check_size(w, h, 0, avctx) || s->bytestream >= s->bytestream_end)
174  return AVERROR_INVALIDDATA;
175 
176  ret = ff_set_dimensions(avctx, w, h);
177  if (ret < 0)
178  return ret;
179 
180  if (avctx->pix_fmt == AV_PIX_FMT_GBRPF32) {
181  pnm_get(s, buf1, sizeof(buf1));
182  if (av_sscanf(buf1, "%f", &s->scale) != 1 || s->scale == 0.0 || !isfinite(s->scale)) {
183  av_log(avctx, AV_LOG_ERROR, "Invalid scale.\n");
184  return AVERROR_INVALIDDATA;
185  }
186  s->endian = s->scale < 0.f;
187  s->scale = fabsf(s->scale);
188  s->maxval = (1ULL << 32) - 1;
189  } else if (avctx->pix_fmt != AV_PIX_FMT_MONOWHITE && avctx->pix_fmt != AV_PIX_FMT_MONOBLACK) {
190  pnm_get(s, buf1, sizeof(buf1));
191  s->maxval = atoi(buf1);
192  if (s->maxval <= 0 || s->maxval > UINT16_MAX) {
193  av_log(avctx, AV_LOG_ERROR, "Invalid maxval: %d\n", s->maxval);
194  s->maxval = 255;
195  }
196  if (s->maxval >= 256) {
197  if (avctx->pix_fmt == AV_PIX_FMT_GRAY8) {
198  avctx->pix_fmt = AV_PIX_FMT_GRAY16;
199  } else if (avctx->pix_fmt == AV_PIX_FMT_RGB24) {
200  avctx->pix_fmt = AV_PIX_FMT_RGB48;
201  } else if (avctx->pix_fmt == AV_PIX_FMT_YUV420P && s->maxval < 65536) {
202  if (s->maxval < 512)
203  avctx->pix_fmt = AV_PIX_FMT_YUV420P9;
204  else if (s->maxval < 1024)
205  avctx->pix_fmt = AV_PIX_FMT_YUV420P10;
206  else
207  avctx->pix_fmt = AV_PIX_FMT_YUV420P16;
208  } else {
209  av_log(avctx, AV_LOG_ERROR, "Unsupported pixel format\n");
210  avctx->pix_fmt = AV_PIX_FMT_NONE;
211  return AVERROR_INVALIDDATA;
212  }
213  }
214  }else
215  s->maxval=1;
216 
217  if (!pnm_space(s->bytestream[-1]))
218  return AVERROR_INVALIDDATA;
219 
220  /* more check if YUV420 */
222  if ((avctx->width & 1) != 0)
223  return AVERROR_INVALIDDATA;
224  h = (avctx->height * 2);
225  if ((h % 3) != 0)
226  return AVERROR_INVALIDDATA;
227  h /= 3;
228  avctx->height = h;
229  }
230  return 0;
231 }
#define NULL
Definition: coverity.c:32
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
const AVPixFmtDescriptor * av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
Definition: pixdesc.c:2573
static int pnm_space(int c)
Definition: pnm.c:32
misc image utilities
packed RGB 8:8:8, 24bpp, RGBRGB...
Definition: pixfmt.h:68
int ff_set_dimensions(AVCodecContext *s, int width, int height)
Check that the provided frame dimensions are valid and set them on the codec context.
Definition: utils.c:106
#define AV_PIX_FMT_RGBA64
Definition: pixfmt.h:389
int maxval
maximum value of a pixel
Definition: pnm.h:31
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:736
uint8_t * bytestream
Definition: pnm.h:28
float scale
Definition: pnm.h:34
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
uint8_t
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:92
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
#define isfinite(x)
Definition: libm.h:359
#define AV_PIX_FMT_YA16
Definition: pixfmt.h:384
#define AV_PIX_FMT_RGB48
Definition: pixfmt.h:385
simple assert() macros that are a bit more flexible than ISO C assert().
static void pnm_get(PNMContext *sc, char *str, int buf_size)
Definition: pnm.c:37
uint8_t * bytestream_end
Definition: pnm.h:30
int av_sscanf(const char *string, const char *format,...)
See libc sscanf manual for more information.
Definition: avsscanf.c:962
packed RGBA 8:8:8:8, 32bpp, RGBARGBA...
Definition: pixfmt.h:93
uint64_t flags
Combination of AV_PIX_FMT_FLAG_...
Definition: pixdesc.h:106
int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
Check if the given dimension of an image is valid, meaning that all bytes of the image can be address...
Definition: imgutils.c:317
alias for AV_PIX_FMT_YA8
Definition: pixfmt.h:146
#define AV_PIX_FMT_GRAY16
Definition: pixfmt.h:383
int width
picture width / height.
Definition: avcodec.h:699
uint8_t w
Definition: llviddspenc.c:38
#define s(width, name)
Definition: cbs_vp9.c:257
#define AV_PIX_FMT_YUV420P16
Definition: pixfmt.h:410
Definition: pnm.h:27
Libavcodec external API header.
enum AVCodecID codec_id
Definition: avcodec.h:536
int ff_pnm_decode_header(AVCodecContext *avctx, PNMContext *const s)
Definition: pnm.c:65
main external API structure.
Definition: avcodec.h:526
#define AV_PIX_FMT_YUV420P10
Definition: pixfmt.h:399
#define AV_PIX_FMT_YUV420P9
Definition: pixfmt.h:396
int endian
Definition: pnm.h:33
#define AV_PIX_FMT_GBRPF32
Definition: pixfmt.h:428
Y , 1bpp, 0 is black, 1 is white, in each byte pixels are ordered from the msb to the lsb...
Definition: pixfmt.h:76
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:66
Y , 8bpp.
Definition: pixfmt.h:74
common internal api header.
Y , 1bpp, 0 is white, 1 is black, in each byte pixels are ordered from the msb to the lsb...
Definition: pixfmt.h:75
#define AV_PIX_FMT_FLAG_PLANAR
At least one pixel component is not in the first data plane.
Definition: pixdesc.h:144
int type
Definition: pnm.h:32