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 
65 int ff_pnm_decode_header(AVCodecContext *avctx, PNMContext * const s)
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) {
86  avctx->pix_fmt = AV_PIX_FMT_MONOWHITE;
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 */
221  if (av_pix_fmt_desc_get(avctx->pix_fmt)->flags & AV_PIX_FMT_FLAG_PLANAR) {
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 }
pnm_space
static int pnm_space(int c)
Definition: pnm.c:32
av_pix_fmt_desc_get
const AVPixFmtDescriptor * av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
Definition: pixdesc.c:2549
end
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:92
w
uint8_t w
Definition: llviddspenc.c:38
internal.h
PNMContext::bytestream_end
uint8_t * bytestream_end
Definition: pnm.h:30
AV_PIX_FMT_MONOWHITE
@ AV_PIX_FMT_MONOWHITE
Y , 1bpp, 0 is white, 1 is black, in each byte pixels are ordered from the msb to the lsb.
Definition: pixfmt.h:75
AV_PIX_FMT_YUV420P10
#define AV_PIX_FMT_YUV420P10
Definition: pixfmt.h:397
pnm_get
static void pnm_get(PNMContext *sc, char *str, int buf_size)
Definition: pnm.c:37
AV_PIX_FMT_GRAY16
#define AV_PIX_FMT_GRAY16
Definition: pixfmt.h:381
avassert.h
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
s
#define s(width, name)
Definition: cbs_vp9.c:257
av_assert0
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
AV_PIX_FMT_YUV420P9
#define AV_PIX_FMT_YUV420P9
Definition: pixfmt.h:394
AV_PIX_FMT_YUV420P16
#define AV_PIX_FMT_YUV420P16
Definition: pixfmt.h:408
isfinite
#define isfinite(x)
Definition: libm.h:359
AV_PIX_FMT_YUV420P
@ AV_PIX_FMT_YUV420P
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:66
AV_PIX_FMT_RGBA
@ AV_PIX_FMT_RGBA
packed RGBA 8:8:8:8, 32bpp, RGBARGBA...
Definition: pixfmt.h:93
AVCodecContext::codec_id
enum AVCodecID codec_id
Definition: avcodec.h:536
AV_PIX_FMT_GRAY8A
@ AV_PIX_FMT_GRAY8A
alias for AV_PIX_FMT_YA8
Definition: pixfmt.h:146
AV_PIX_FMT_RGBA64
#define AV_PIX_FMT_RGBA64
Definition: pixfmt.h:387
av_sscanf
int av_sscanf(const char *string, const char *format,...)
See libc sscanf manual for more information.
Definition: avsscanf.c:962
NULL
#define NULL
Definition: coverity.c:32
AV_PIX_FMT_MONOBLACK
@ AV_PIX_FMT_MONOBLACK
Y , 1bpp, 0 is black, 1 is white, in each byte pixels are ordered from the msb to the lsb.
Definition: pixfmt.h:76
AV_CODEC_ID_PGMYUV
@ AV_CODEC_ID_PGMYUV
Definition: codec_id.h:114
AV_PIX_FMT_GRAY8
@ AV_PIX_FMT_GRAY8
Y , 8bpp.
Definition: pixfmt.h:74
AVPixFmtDescriptor::flags
uint64_t flags
Combination of AV_PIX_FMT_FLAG_...
Definition: pixdesc.h:106
c
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
pnm.h
AV_PIX_FMT_RGB24
@ AV_PIX_FMT_RGB24
packed RGB 8:8:8, 24bpp, RGBRGB...
Definition: pixfmt.h:68
AV_PIX_FMT_GBRPF32
#define AV_PIX_FMT_GBRPF32
Definition: pixfmt.h:426
AV_PIX_FMT_RGB48
#define AV_PIX_FMT_RGB48
Definition: pixfmt.h:383
PNMContext
Definition: pnm.h:27
AV_PIX_FMT_YA16
#define AV_PIX_FMT_YA16
Definition: pixfmt.h:382
uint8_t
uint8_t
Definition: audio_convert.c:194
AVCodecContext::height
int height
Definition: avcodec.h:699
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:736
avcodec.h
ret
ret
Definition: filter_design.txt:187
PNMContext::bytestream
uint8_t * bytestream
Definition: pnm.h:28
AVCodecContext
main external API structure.
Definition: avcodec.h:526
AV_PIX_FMT_NONE
@ AV_PIX_FMT_NONE
Definition: pixfmt.h:65
AV_PIX_FMT_FLAG_PLANAR
#define AV_PIX_FMT_FLAG_PLANAR
At least one pixel component is not in the first data plane.
Definition: pixdesc.h:144
ff_set_dimensions
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:104
ff_pnm_decode_header
int ff_pnm_decode_header(AVCodecContext *avctx, PNMContext *const s)
Definition: pnm.c:65
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:699
convert_header.str
string str
Definition: convert_header.py:20
imgutils.h
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
h
h
Definition: vp9dsp_template.c:2038
avstring.h
av_image_check_size
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:282
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