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 "decode.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  const 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[1] != 'H' &&
78  s->bytestream[1] != 'h')) {
79  s->bytestream += s->bytestream_end > s->bytestream;
80  s->bytestream += s->bytestream_end > s->bytestream;
81  return AVERROR_INVALIDDATA;
82  }
83  pnm_get(s, buf1, sizeof(buf1));
84  s->type= buf1[1]-'0';
85  s->half = 0;
86 
87  if (buf1[1] == 'F') {
88  avctx->pix_fmt = AV_PIX_FMT_GBRPF32;
89  } else if (buf1[1] == 'f') {
90  avctx->pix_fmt = AV_PIX_FMT_GRAYF32;
91  } else if (buf1[1] == 'H') {
92  avctx->pix_fmt = AV_PIX_FMT_GBRPF32;
93  s->half = 1;
94  } else if (buf1[1] == 'h') {
95  avctx->pix_fmt = AV_PIX_FMT_GRAYF32;
96  s->half = 1;
97  } else if (s->type==1 || s->type==4) {
98  avctx->pix_fmt = AV_PIX_FMT_MONOWHITE;
99  } else if (s->type==2 || s->type==5) {
100  if (avctx->codec_id == AV_CODEC_ID_PGMYUV) {
101  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
102  avctx->color_range = AVCOL_RANGE_MPEG;
103  } else {
104  avctx->pix_fmt = AV_PIX_FMT_GRAY8;
105  }
106  } else if (s->type==3 || s->type==6) {
107  avctx->pix_fmt = AV_PIX_FMT_RGB24;
108  } else if (s->type==7) {
109  w = -1;
110  h = -1;
111  maxval = -1;
112  depth = -1;
113  tuple_type[0] = '\0';
114  for (;;) {
115  pnm_get(s, buf1, sizeof(buf1));
116  if (!strcmp(buf1, "WIDTH")) {
117  pnm_get(s, buf1, sizeof(buf1));
118  w = strtol(buf1, NULL, 10);
119  } else if (!strcmp(buf1, "HEIGHT")) {
120  pnm_get(s, buf1, sizeof(buf1));
121  h = strtol(buf1, NULL, 10);
122  } else if (!strcmp(buf1, "DEPTH")) {
123  pnm_get(s, buf1, sizeof(buf1));
124  depth = strtol(buf1, NULL, 10);
125  } else if (!strcmp(buf1, "MAXVAL")) {
126  pnm_get(s, buf1, sizeof(buf1));
127  maxval = strtol(buf1, NULL, 10);
128  } else if (!strcmp(buf1, "TUPLTYPE") ||
129  /* libavcodec used to write invalid files */
130  !strcmp(buf1, "TUPLETYPE")) {
131  pnm_get(s, tuple_type, sizeof(tuple_type));
132  } else if (!strcmp(buf1, "ENDHDR")) {
133  break;
134  } else {
135  return AVERROR_INVALIDDATA;
136  }
137  }
138  if (!pnm_space(s->bytestream[-1]))
139  return AVERROR_INVALIDDATA;
140 
141  /* check that all tags are present */
142  if (w <= 0 || h <= 0 || maxval <= 0 || maxval > UINT16_MAX || depth <= 0 || tuple_type[0] == '\0' ||
143  av_image_check_size(w, h, 0, avctx) || s->bytestream >= s->bytestream_end)
144  return AVERROR_INVALIDDATA;
145 
146  ret = ff_set_dimensions(avctx, w, h);
147  if (ret < 0)
148  return ret;
149  s->maxval = maxval;
150  if (depth == 1) {
151  if (maxval == 1) {
152  avctx->pix_fmt = AV_PIX_FMT_MONOBLACK;
153  } else if (maxval < 256) {
154  avctx->pix_fmt = AV_PIX_FMT_GRAY8;
155  } else {
156  avctx->pix_fmt = AV_PIX_FMT_GRAY16;
157  }
158  } else if (depth == 2) {
159  if (maxval < 256) {
160  avctx->pix_fmt = AV_PIX_FMT_GRAY8A;
161  } else {
162  avctx->pix_fmt = AV_PIX_FMT_YA16;
163  }
164  } else if (depth == 3) {
165  if (maxval < 256) {
166  avctx->pix_fmt = AV_PIX_FMT_RGB24;
167  } else {
168  avctx->pix_fmt = AV_PIX_FMT_RGB48;
169  }
170  } else if (depth == 4) {
171  if (maxval < 256) {
172  avctx->pix_fmt = AV_PIX_FMT_RGBA;
173  } else {
174  avctx->pix_fmt = AV_PIX_FMT_RGBA64;
175  }
176  } else {
177  return AVERROR_INVALIDDATA;
178  }
179  return 0;
180  } else {
181  av_assert0(0);
182  }
183  pnm_get(s, buf1, sizeof(buf1));
184  w = atoi(buf1);
185  pnm_get(s, buf1, sizeof(buf1));
186  h = atoi(buf1);
187  if(w <= 0 || h <= 0 || av_image_check_size(w, h, 0, avctx) || s->bytestream >= s->bytestream_end)
188  return AVERROR_INVALIDDATA;
189 
190  ret = ff_set_dimensions(avctx, w, h);
191  if (ret < 0)
192  return ret;
193 
194  if (avctx->pix_fmt == AV_PIX_FMT_GBRPF32 || avctx->pix_fmt == AV_PIX_FMT_GRAYF32) {
195  pnm_get(s, buf1, sizeof(buf1));
196  if (av_sscanf(buf1, "%f", &s->scale) != 1 || s->scale == 0.0 || !isfinite(s->scale)) {
197  av_log(avctx, AV_LOG_ERROR, "Invalid scale.\n");
198  return AVERROR_INVALIDDATA;
199  }
200  s->endian = s->scale < 0.f;
201  s->scale = fabsf(s->scale);
202  s->maxval = (1ULL << 32) - 1;
203  } else if (avctx->pix_fmt != AV_PIX_FMT_MONOWHITE && avctx->pix_fmt != AV_PIX_FMT_MONOBLACK) {
204  pnm_get(s, buf1, sizeof(buf1));
205  s->maxval = atoi(buf1);
206  if (s->maxval <= 0 || s->maxval > UINT16_MAX) {
207  av_log(avctx, AV_LOG_ERROR, "Invalid maxval: %d\n", s->maxval);
208  s->maxval = 255;
209  }
210  if (s->maxval >= 256) {
211  if (avctx->pix_fmt == AV_PIX_FMT_GRAY8) {
212  avctx->pix_fmt = AV_PIX_FMT_GRAY16;
213  } else if (avctx->pix_fmt == AV_PIX_FMT_RGB24) {
214  avctx->pix_fmt = AV_PIX_FMT_RGB48;
215  } else if (avctx->pix_fmt == AV_PIX_FMT_YUV420P && s->maxval < 65536) {
216  if (s->maxval < 512)
217  avctx->pix_fmt = AV_PIX_FMT_YUV420P9;
218  else if (s->maxval < 1024)
219  avctx->pix_fmt = AV_PIX_FMT_YUV420P10;
220  else
221  avctx->pix_fmt = AV_PIX_FMT_YUV420P16;
222  } else {
223  av_log(avctx, AV_LOG_ERROR, "Unsupported pixel format\n");
224  avctx->pix_fmt = AV_PIX_FMT_NONE;
225  return AVERROR_INVALIDDATA;
226  }
227  }
228  }else
229  s->maxval=1;
230 
231  if (!pnm_space(s->bytestream[-1]))
232  return AVERROR_INVALIDDATA;
233 
234  /* more check if YUV420 */
235  if ((av_pix_fmt_desc_get(avctx->pix_fmt)->flags & AV_PIX_FMT_FLAG_PLANAR) &&
236  avctx->pix_fmt != AV_PIX_FMT_GBRPF32) {
237  if ((avctx->width & 1) != 0)
238  return AVERROR_INVALIDDATA;
239  h = (avctx->height * 2);
240  if ((h % 3) != 0)
241  return AVERROR_INVALIDDATA;
242  h /= 3;
243  avctx->height = h;
244  }
245  return 0;
246 }
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:3341
w
uint8_t w
Definition: llviddspenc.c:38
PNMContext::bytestream_end
const uint8_t * bytestream_end
Definition: pnm.h:31
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:82
AV_PIX_FMT_YUV420P10
#define AV_PIX_FMT_YUV420P10
Definition: pixfmt.h:528
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:91
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:511
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:210
s
#define s(width, name)
Definition: cbs_vp9.c:198
av_assert0
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:41
AV_PIX_FMT_YUV420P9
#define AV_PIX_FMT_YUV420P9
Definition: pixfmt.h:525
AV_PIX_FMT_YUV420P16
#define AV_PIX_FMT_YUV420P16
Definition: pixfmt.h:539
decode.h
isfinite
#define isfinite(x)
Definition: libm.h:361
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:73
AV_PIX_FMT_GRAYF32
#define AV_PIX_FMT_GRAYF32
Definition: pixfmt.h:565
AV_PIX_FMT_RGBA
@ AV_PIX_FMT_RGBA
packed RGBA 8:8:8:8, 32bpp, RGBARGBA...
Definition: pixfmt.h:100
AVCodecContext::codec_id
enum AVCodecID codec_id
Definition: avcodec.h:441
AV_PIX_FMT_GRAY8A
@ AV_PIX_FMT_GRAY8A
alias for AV_PIX_FMT_YA8
Definition: pixfmt.h:143
AV_PIX_FMT_RGBA64
#define AV_PIX_FMT_RGBA64
Definition: pixfmt.h:518
av_sscanf
int av_sscanf(const char *string, const char *format,...)
See libc sscanf manual for more information.
Definition: avsscanf.c:961
NULL
#define NULL
Definition: coverity.c:32
AVCodecContext::color_range
enum AVColorRange color_range
MPEG vs JPEG YUV range.
Definition: avcodec.h:669
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:83
AV_CODEC_ID_PGMYUV
@ AV_CODEC_ID_PGMYUV
Definition: codec_id.h:117
AV_PIX_FMT_GRAY8
@ AV_PIX_FMT_GRAY8
Y , 8bpp.
Definition: pixfmt.h:81
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:75
AV_PIX_FMT_GBRPF32
#define AV_PIX_FMT_GBRPF32
Definition: pixfmt.h:561
AV_PIX_FMT_RGB48
#define AV_PIX_FMT_RGB48
Definition: pixfmt.h:514
PNMContext
Definition: pnm.h:28
AV_PIX_FMT_YA16
#define AV_PIX_FMT_YA16
Definition: pixfmt.h:513
AVCodecContext::height
int height
Definition: avcodec.h:592
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:631
AVCOL_RANGE_MPEG
@ AVCOL_RANGE_MPEG
Narrow or limited range content.
Definition: pixfmt.h:733
avcodec.h
ret
ret
Definition: filter_design.txt:187
AVCodecContext
main external API structure.
Definition: avcodec.h:431
AV_PIX_FMT_NONE
@ AV_PIX_FMT_NONE
Definition: pixfmt.h:72
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
PNMContext::bytestream
const uint8_t * bytestream
Definition: pnm.h:29
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:592
imgutils.h
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
h
h
Definition: vp9dsp_template.c:2070
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
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