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/imgutils.h"
26 #include "avcodec.h"
27 #include "internal.h"
28 #include "pnm.h"
29 
30 static inline int pnm_space(int c)
31 {
32  return c == ' ' || c == '\n' || c == '\r' || c == '\t';
33 }
34 
35 static void pnm_get(PNMContext *sc, char *str, int buf_size)
36 {
37  char *s;
38  int c;
39  uint8_t *bs = sc->bytestream;
40  const uint8_t *end = sc->bytestream_end;
41 
42  /* skip spaces and comments */
43  while (bs < end) {
44  c = *bs++;
45  if (c == '#') {
46  while (c != '\n' && bs < end) {
47  c = *bs++;
48  }
49  } else if (!pnm_space(c)) {
50  break;
51  }
52  }
53 
54  s = str;
55  while (bs < end && !pnm_space(c) && (s - str) < buf_size - 1) {
56  *s++ = c;
57  c = *bs++;
58  }
59  *s = '\0';
60  while (bs < end && !pnm_space(c))
61  c = *bs++;
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  pnm_get(s, buf1, sizeof(buf1));
72  if(buf1[0] != 'P')
73  return AVERROR_INVALIDDATA;
74  s->type= buf1[1]-'0';
75 
76  if (s->type==1 || s->type==4) {
78  } else if (s->type==2 || s->type==5) {
79  if (avctx->codec_id == AV_CODEC_ID_PGMYUV)
80  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
81  else
82  avctx->pix_fmt = AV_PIX_FMT_GRAY8;
83  } else if (s->type==3 || s->type==6) {
84  avctx->pix_fmt = AV_PIX_FMT_RGB24;
85  } else if (s->type==7) {
86  w = -1;
87  h = -1;
88  maxval = -1;
89  depth = -1;
90  tuple_type[0] = '\0';
91  for (;;) {
92  pnm_get(s, buf1, sizeof(buf1));
93  if (!strcmp(buf1, "WIDTH")) {
94  pnm_get(s, buf1, sizeof(buf1));
95  w = strtol(buf1, NULL, 10);
96  } else if (!strcmp(buf1, "HEIGHT")) {
97  pnm_get(s, buf1, sizeof(buf1));
98  h = strtol(buf1, NULL, 10);
99  } else if (!strcmp(buf1, "DEPTH")) {
100  pnm_get(s, buf1, sizeof(buf1));
101  depth = strtol(buf1, NULL, 10);
102  } else if (!strcmp(buf1, "MAXVAL")) {
103  pnm_get(s, buf1, sizeof(buf1));
104  maxval = strtol(buf1, NULL, 10);
105  } else if (!strcmp(buf1, "TUPLTYPE") ||
106  /* libavcodec used to write invalid files */
107  !strcmp(buf1, "TUPLETYPE")) {
108  pnm_get(s, tuple_type, sizeof(tuple_type));
109  } else if (!strcmp(buf1, "ENDHDR")) {
110  break;
111  } else {
112  return AVERROR_INVALIDDATA;
113  }
114  }
115  /* check that all tags are present */
116  if (w <= 0 || h <= 0 || maxval <= 0 || maxval > UINT16_MAX || depth <= 0 || tuple_type[0] == '\0' ||
117  av_image_check_size(w, h, 0, avctx) || s->bytestream >= s->bytestream_end)
118  return AVERROR_INVALIDDATA;
119 
120  ret = ff_set_dimensions(avctx, w, h);
121  if (ret < 0)
122  return ret;
123  s->maxval = maxval;
124  if (depth == 1) {
125  if (maxval == 1) {
126  avctx->pix_fmt = AV_PIX_FMT_MONOBLACK;
127  } else if (maxval < 256) {
128  avctx->pix_fmt = AV_PIX_FMT_GRAY8;
129  } else {
130  avctx->pix_fmt = AV_PIX_FMT_GRAY16;
131  }
132  } else if (depth == 2) {
133  if (maxval < 256) {
134  avctx->pix_fmt = AV_PIX_FMT_GRAY8A;
135  } else {
136  avctx->pix_fmt = AV_PIX_FMT_YA16;
137  }
138  } else if (depth == 3) {
139  if (maxval < 256) {
140  avctx->pix_fmt = AV_PIX_FMT_RGB24;
141  } else {
142  avctx->pix_fmt = AV_PIX_FMT_RGB48;
143  }
144  } else if (depth == 4) {
145  if (maxval < 256) {
146  avctx->pix_fmt = AV_PIX_FMT_RGBA;
147  } else {
148  avctx->pix_fmt = AV_PIX_FMT_RGBA64;
149  }
150  } else {
151  return AVERROR_INVALIDDATA;
152  }
153  return 0;
154  } else {
155  return AVERROR_INVALIDDATA;
156  }
157  pnm_get(s, buf1, sizeof(buf1));
158  w = atoi(buf1);
159  pnm_get(s, buf1, sizeof(buf1));
160  h = atoi(buf1);
161  if(w <= 0 || h <= 0 || av_image_check_size(w, h, 0, avctx) || s->bytestream >= s->bytestream_end)
162  return AVERROR_INVALIDDATA;
163 
164  ret = ff_set_dimensions(avctx, w, h);
165  if (ret < 0)
166  return ret;
167 
168  if (avctx->pix_fmt != AV_PIX_FMT_MONOWHITE && avctx->pix_fmt != AV_PIX_FMT_MONOBLACK) {
169  pnm_get(s, buf1, sizeof(buf1));
170  s->maxval = atoi(buf1);
171  if (s->maxval <= 0 || s->maxval > UINT16_MAX) {
172  av_log(avctx, AV_LOG_ERROR, "Invalid maxval: %d\n", s->maxval);
173  s->maxval = 255;
174  }
175  if (s->maxval >= 256) {
176  if (avctx->pix_fmt == AV_PIX_FMT_GRAY8) {
177  avctx->pix_fmt = AV_PIX_FMT_GRAY16;
178  } else if (avctx->pix_fmt == AV_PIX_FMT_RGB24) {
179  avctx->pix_fmt = AV_PIX_FMT_RGB48;
180  } else if (avctx->pix_fmt == AV_PIX_FMT_YUV420P && s->maxval < 65536) {
181  if (s->maxval < 512)
182  avctx->pix_fmt = AV_PIX_FMT_YUV420P9;
183  else if (s->maxval < 1024)
184  avctx->pix_fmt = AV_PIX_FMT_YUV420P10;
185  else
186  avctx->pix_fmt = AV_PIX_FMT_YUV420P16;
187  } else {
188  av_log(avctx, AV_LOG_ERROR, "Unsupported pixel format\n");
189  avctx->pix_fmt = AV_PIX_FMT_NONE;
190  return AVERROR_INVALIDDATA;
191  }
192  }
193  }else
194  s->maxval=1;
195  /* more check if YUV420 */
197  if ((avctx->width & 1) != 0)
198  return AVERROR_INVALIDDATA;
199  h = (avctx->height * 2);
200  if ((h % 3) != 0)
201  return AVERROR_INVALIDDATA;
202  h /= 3;
203  avctx->height = h;
204  }
205  return 0;
206 }
#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:2522
static int pnm_space(int c)
Definition: pnm.c:30
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:104
#define AV_PIX_FMT_RGBA64
Definition: pixfmt.h:377
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:1775
uint8_t * bytestream
Definition: pnm.h:28
uint8_t
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
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:176
#define AV_PIX_FMT_YA16
Definition: pixfmt.h:372
#define AV_PIX_FMT_RGB48
Definition: pixfmt.h:373
static void pnm_get(PNMContext *sc, char *str, int buf_size)
Definition: pnm.c:35
uint8_t * bytestream_end
Definition: pnm.h:30
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:282
alias for AV_PIX_FMT_YA8
Definition: pixfmt.h:146
#define AV_PIX_FMT_GRAY16
Definition: pixfmt.h:371
int width
picture width / height.
Definition: avcodec.h:1738
uint8_t w
Definition: llviddspenc.c:38
#define s(width, name)
Definition: cbs_vp9.c:257
#define AV_PIX_FMT_YUV420P16
Definition: pixfmt.h:398
Definition: pnm.h:27
Libavcodec external API header.
enum AVCodecID codec_id
Definition: avcodec.h:1575
int ff_pnm_decode_header(AVCodecContext *avctx, PNMContext *const s)
Definition: pnm.c:65
main external API structure.
Definition: avcodec.h:1565
#define AV_PIX_FMT_YUV420P10
Definition: pixfmt.h:387
#define AV_PIX_FMT_YUV420P9
Definition: pixfmt.h:384
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