FFmpeg
pnm.c
Go to the documentation of this file.
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[1] != 'F')) {
77  s->bytestream += s->bytestream_end > s->bytestream;
78  s->bytestream += s->bytestream_end > s->bytestream;
79  return AVERROR_INVALIDDATA;
80  }
81  pnm_get(s, buf1, sizeof(buf1));
82  s->type= buf1[1]-'0';
83 
84  if (buf1[1] == 'F') {
85  avctx->pix_fmt = AV_PIX_FMT_GBRPF32;
86  } else if (buf1[1] == 'f') {
87  avctx->pix_fmt = AV_PIX_FMT_GRAYF32;
88  } else if (s->type==1 || s->type==4) {
89  avctx->pix_fmt = AV_PIX_FMT_MONOWHITE;
90  } else if (s->type==2 || s->type==5) {
91  if (avctx->codec_id == AV_CODEC_ID_PGMYUV)
92  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
93  else
94  avctx->pix_fmt = AV_PIX_FMT_GRAY8;
95  } else if (s->type==3 || s->type==6) {
96  avctx->pix_fmt = AV_PIX_FMT_RGB24;
97  } else if (s->type==7) {
98  w = -1;
99  h = -1;
100  maxval = -1;
101  depth = -1;
102  tuple_type[0] = '\0';
103  for (;;) {
104  pnm_get(s, buf1, sizeof(buf1));
105  if (!strcmp(buf1, "WIDTH")) {
106  pnm_get(s, buf1, sizeof(buf1));
107  w = strtol(buf1, NULL, 10);
108  } else if (!strcmp(buf1, "HEIGHT")) {
109  pnm_get(s, buf1, sizeof(buf1));
110  h = strtol(buf1, NULL, 10);
111  } else if (!strcmp(buf1, "DEPTH")) {
112  pnm_get(s, buf1, sizeof(buf1));
113  depth = strtol(buf1, NULL, 10);
114  } else if (!strcmp(buf1, "MAXVAL")) {
115  pnm_get(s, buf1, sizeof(buf1));
116  maxval = strtol(buf1, NULL, 10);
117  } else if (!strcmp(buf1, "TUPLTYPE") ||
118  /* libavcodec used to write invalid files */
119  !strcmp(buf1, "TUPLETYPE")) {
120  pnm_get(s, tuple_type, sizeof(tuple_type));
121  } else if (!strcmp(buf1, "ENDHDR")) {
122  break;
123  } else {
124  return AVERROR_INVALIDDATA;
125  }
126  }
127  if (!pnm_space(s->bytestream[-1]))
128  return AVERROR_INVALIDDATA;
129 
130  /* check that all tags are present */
131  if (w <= 0 || h <= 0 || maxval <= 0 || maxval > UINT16_MAX || depth <= 0 || tuple_type[0] == '\0' ||
132  av_image_check_size(w, h, 0, avctx) || s->bytestream >= s->bytestream_end)
133  return AVERROR_INVALIDDATA;
134 
135  ret = ff_set_dimensions(avctx, w, h);
136  if (ret < 0)
137  return ret;
138  s->maxval = maxval;
139  if (depth == 1) {
140  if (maxval == 1) {
141  avctx->pix_fmt = AV_PIX_FMT_MONOBLACK;
142  } else if (maxval < 256) {
143  avctx->pix_fmt = AV_PIX_FMT_GRAY8;
144  } else {
145  avctx->pix_fmt = AV_PIX_FMT_GRAY16;
146  }
147  } else if (depth == 2) {
148  if (maxval < 256) {
149  avctx->pix_fmt = AV_PIX_FMT_GRAY8A;
150  } else {
151  avctx->pix_fmt = AV_PIX_FMT_YA16;
152  }
153  } else if (depth == 3) {
154  if (maxval < 256) {
155  avctx->pix_fmt = AV_PIX_FMT_RGB24;
156  } else {
157  avctx->pix_fmt = AV_PIX_FMT_RGB48;
158  }
159  } else if (depth == 4) {
160  if (maxval < 256) {
161  avctx->pix_fmt = AV_PIX_FMT_RGBA;
162  } else {
163  avctx->pix_fmt = AV_PIX_FMT_RGBA64;
164  }
165  } else {
166  return AVERROR_INVALIDDATA;
167  }
168  return 0;
169  } else {
170  av_assert0(0);
171  }
172  pnm_get(s, buf1, sizeof(buf1));
173  w = atoi(buf1);
174  pnm_get(s, buf1, sizeof(buf1));
175  h = atoi(buf1);
176  if(w <= 0 || h <= 0 || av_image_check_size(w, h, 0, avctx) || s->bytestream >= s->bytestream_end)
177  return AVERROR_INVALIDDATA;
178 
179  ret = ff_set_dimensions(avctx, w, h);
180  if (ret < 0)
181  return ret;
182 
183  if (avctx->pix_fmt == AV_PIX_FMT_GBRPF32 || avctx->pix_fmt == AV_PIX_FMT_GRAYF32) {
184  pnm_get(s, buf1, sizeof(buf1));
185  if (av_sscanf(buf1, "%f", &s->scale) != 1 || s->scale == 0.0 || !isfinite(s->scale)) {
186  av_log(avctx, AV_LOG_ERROR, "Invalid scale.\n");
187  return AVERROR_INVALIDDATA;
188  }
189  s->endian = s->scale < 0.f;
190  s->scale = fabsf(s->scale);
191  s->maxval = (1ULL << 32) - 1;
192  } else if (avctx->pix_fmt != AV_PIX_FMT_MONOWHITE && avctx->pix_fmt != AV_PIX_FMT_MONOBLACK) {
193  pnm_get(s, buf1, sizeof(buf1));
194  s->maxval = atoi(buf1);
195  if (s->maxval <= 0 || s->maxval > UINT16_MAX) {
196  av_log(avctx, AV_LOG_ERROR, "Invalid maxval: %d\n", s->maxval);
197  s->maxval = 255;
198  }
199  if (s->maxval >= 256) {
200  if (avctx->pix_fmt == AV_PIX_FMT_GRAY8) {
201  avctx->pix_fmt = AV_PIX_FMT_GRAY16;
202  } else if (avctx->pix_fmt == AV_PIX_FMT_RGB24) {
203  avctx->pix_fmt = AV_PIX_FMT_RGB48;
204  } else if (avctx->pix_fmt == AV_PIX_FMT_YUV420P && s->maxval < 65536) {
205  if (s->maxval < 512)
206  avctx->pix_fmt = AV_PIX_FMT_YUV420P9;
207  else if (s->maxval < 1024)
208  avctx->pix_fmt = AV_PIX_FMT_YUV420P10;
209  else
210  avctx->pix_fmt = AV_PIX_FMT_YUV420P16;
211  } else {
212  av_log(avctx, AV_LOG_ERROR, "Unsupported pixel format\n");
213  avctx->pix_fmt = AV_PIX_FMT_NONE;
214  return AVERROR_INVALIDDATA;
215  }
216  }
217  }else
218  s->maxval=1;
219 
220  if (!pnm_space(s->bytestream[-1]))
221  return AVERROR_INVALIDDATA;
222 
223  /* more check if YUV420 */
224  if ((av_pix_fmt_desc_get(avctx->pix_fmt)->flags & AV_PIX_FMT_FLAG_PLANAR) &&
225  avctx->pix_fmt != AV_PIX_FMT_GBRPF32) {
226  if ((avctx->width & 1) != 0)
227  return AVERROR_INVALIDDATA;
228  h = (avctx->height * 2);
229  if ((h % 3) != 0)
230  return AVERROR_INVALIDDATA;
231  h /= 3;
232  avctx->height = h;
233  }
234  return 0;
235 }
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:2540
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:389
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:373
fabsf
static __device__ float fabsf(float a)
Definition: cuda_runtime.h:181
avassert.h
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
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:386
AV_PIX_FMT_YUV420P16
#define AV_PIX_FMT_YUV420P16
Definition: pixfmt.h:400
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_GRAYF32
#define AV_PIX_FMT_GRAYF32
Definition: pixfmt.h:421
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:389
AV_PIX_FMT_GRAY8A
@ AV_PIX_FMT_GRAY8A
alias for AV_PIX_FMT_YA8
Definition: pixfmt.h:136
AV_PIX_FMT_RGBA64
#define AV_PIX_FMT_RGBA64
Definition: pixfmt.h:379
av_sscanf
int av_sscanf(const char *string, const char *format,...)
See libc sscanf manual for more information.
Definition: avsscanf.c:960
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:115
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:94
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:418
AV_PIX_FMT_RGB48
#define AV_PIX_FMT_RGB48
Definition: pixfmt.h:375
PNMContext
Definition: pnm.h:27
AV_PIX_FMT_YA16
#define AV_PIX_FMT_YA16
Definition: pixfmt.h:374
AVCodecContext::height
int height
Definition: avcodec.h:552
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:589
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:379
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:132
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:86
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:552
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:318
Generated on Tue Jul 27 2021 19:21:34 for FFmpeg by   doxygen 1.8.17