FFmpeg  4.4.5
fitsdec.c
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1 /*
2  * FITS demuxer
3  * Copyright (c) 2017 Paras Chadha
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 /**
23  * @file
24  * FITS demuxer.
25  */
26 
27 #include "libavutil/avassert.h"
28 #include "libavutil/intreadwrite.h"
29 #include "internal.h"
30 #include "libavutil/opt.h"
31 #include "libavcodec/fits.h"
32 #include "libavutil/bprint.h"
33 
34 #define FITS_BLOCK_SIZE 2880
35 
36 typedef struct FITSContext {
37  const AVClass *class;
41 } FITSContext;
42 
43 static int fits_probe(const AVProbeData *p)
44 {
45  const uint8_t *b = p->buf;
46  if (!memcmp(b, "SIMPLE = T", 30))
47  return AVPROBE_SCORE_MAX - 1;
48  return 0;
49 }
50 
52 {
53  AVStream *st;
54  FITSContext * fits = s->priv_data;
55 
56  st = avformat_new_stream(s, NULL);
57  if (!st)
58  return AVERROR(ENOMEM);
59 
62 
63  avpriv_set_pts_info(st, 64, fits->framerate.den, fits->framerate.num);
64  fits->pts = 0;
65  fits->first_image = 1;
66  return 0;
67 }
68 
69 /**
70  * Parses header and checks that the current HDU contains image or not
71  * It also stores the header in the avbuf and stores the size of data part in data_size
72  * @param s pointer to AVFormat Context
73  * @param fits pointer to FITSContext
74  * @param header pointer to FITSHeader
75  * @param avbuf pointer to AVBPrint to store the header
76  * @param data_size to store the size of data part
77  * @return 1 if image found, 0 if any other extension and AVERROR_INVALIDDATA otherwise
78  */
80  AVBPrint *avbuf, uint64_t *data_size)
81 {
82  int i, ret, image = 0;
83  char buf[FITS_BLOCK_SIZE] = { 0 };
84  int64_t buf_size = 0, size = 0, t;
85 
86  do {
87  ret = avio_read(s->pb, buf, FITS_BLOCK_SIZE);
88  if (ret < 0) {
89  return ret;
90  } else if (ret < FITS_BLOCK_SIZE) {
91  return AVERROR_INVALIDDATA;
92  }
93 
95  ret = 0;
96  buf_size = 0;
97  while(!ret && buf_size < FITS_BLOCK_SIZE) {
98  ret = avpriv_fits_header_parse_line(s, header, buf + buf_size, NULL);
99  buf_size += 80;
100  }
101  } while (!ret);
102  if (ret < 0)
103  return ret;
104 
105  image = fits->first_image || header->image_extension;
106  fits->first_image = 0;
107 
108  if (header->groups) {
109  image = 0;
110  if (header->naxis > 1)
111  size = 1;
112  } else if (header->naxis) {
113  size = header->naxisn[0];
114  } else {
115  image = 0;
116  }
117 
118  for (i = 1; i < header->naxis; i++) {
119  if(size && header->naxisn[i] > UINT64_MAX / size)
120  return AVERROR_INVALIDDATA;
121  size *= header->naxisn[i];
122  }
123 
124  if(header->pcount > UINT64_MAX - size)
125  return AVERROR_INVALIDDATA;
126  size += header->pcount;
127 
128  t = (abs(header->bitpix) >> 3) * ((int64_t) header->gcount);
129  if(size && t > INT64_MAX / size)
130  return AVERROR_INVALIDDATA;
131  size *= t;
132 
133  if (!size) {
134  image = 0;
135  } else {
136  if(FITS_BLOCK_SIZE - 1 > INT64_MAX - size)
137  return AVERROR_INVALIDDATA;
139  }
140  *data_size = size;
141  return image;
142 }
143 
145 {
146  int64_t pos, ret;
147  uint64_t size;
148  FITSContext *fits = s->priv_data;
150  AVBPrint avbuf;
151  char *buf;
152 
153  if (fits->first_image) {
155  } else {
157  }
158 
160  while ((ret = is_image(s, fits, &header, &avbuf, &size)) == 0) {
161  av_bprint_finalize(&avbuf, NULL);
162  pos = avio_skip(s->pb, size);
163  if (pos < 0)
164  return pos;
165 
168  }
169  if (ret < 0)
170  goto fail;
171 
172  if (!av_bprint_is_complete(&avbuf)) {
173  ret = AVERROR(ENOMEM);
174  goto fail;
175  }
176 
177  av_assert0(avbuf.len <= INT64_MAX && size <= INT64_MAX);
178  if (avbuf.len + size > INT_MAX - 80) {
179  ret = AVERROR_INVALIDDATA;
180  goto fail;
181  }
182  // Header is sent with the first line removed...
183  ret = av_new_packet(pkt, avbuf.len - 80 + size);
184  if (ret < 0)
185  goto fail;
186 
187  pkt->stream_index = 0;
189 
190  ret = av_bprint_finalize(&avbuf, &buf);
191  if (ret < 0) {
192  return ret;
193  }
194 
195  memcpy(pkt->data, buf + 80, avbuf.len - 80);
196  pkt->size = avbuf.len - 80;
197  av_freep(&buf);
198  ret = avio_read(s->pb, pkt->data + pkt->size, size);
199  if (ret < 0) {
200  return ret;
201  }
202 
203  pkt->size += ret;
204  pkt->pts = fits->pts;
205  fits->pts++;
206 
207  return 0;
208 
209 fail:
210  av_bprint_finalize(&avbuf, NULL);
211  return ret;
212 }
213 
214 static const AVOption fits_options[] = {
215  { "framerate", "set the framerate", offsetof(FITSContext, framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "1"}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM},
216  { NULL },
217 };
218 
219 static const AVClass fits_demuxer_class = {
220  .class_name = "FITS demuxer",
221  .item_name = av_default_item_name,
222  .option = fits_options,
223  .version = LIBAVUTIL_VERSION_INT,
224 };
225 
227  .name = "fits",
228  .long_name = NULL_IF_CONFIG_SMALL("Flexible Image Transport System"),
229  .priv_data_size = sizeof(FITSContext),
233  .priv_class = &fits_demuxer_class,
234  .raw_codec_id = AV_CODEC_ID_FITS,
235 };
uint8_t
simple assert() macros that are a bit more flexible than ISO C assert().
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:337
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:633
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
Definition: bprint.c:69
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
Definition: bprint.c:235
void av_bprint_append_data(AVBPrint *buf, const char *data, unsigned size)
Append data to a print buffer.
Definition: bprint.c:158
#define AV_BPRINT_SIZE_UNLIMITED
static int av_bprint_is_complete(const AVBPrint *buf)
Test if the print buffer is complete (not truncated).
Definition: bprint.h:185
#define s(width, name)
Definition: cbs_vp9.c:257
#define fail()
Definition: checkasm.h:133
#define NULL
Definition: coverity.c:32
long long int64_t
Definition: coverity.c:34
#define abs(x)
Definition: cuda_runtime.h:35
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:545
int avpriv_fits_header_init(FITSHeader *header, FITSHeaderState state)
Initialize a single header line.
Definition: fits.c:26
int avpriv_fits_header_parse_line(void *avcl, FITSHeader *header, const uint8_t line[80], AVDictionary ***metadata)
Parse a single header line.
Definition: fits.c:108
@ STATE_XTENSION
Definition: fits.h:31
@ STATE_SIMPLE
Definition: fits.h:30
@ AV_OPT_TYPE_VIDEO_RATE
offset must point to AVRational
Definition: opt.h:238
@ AV_CODEC_ID_FITS
Definition: codec_id.h:285
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:410
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:99
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4509
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define AVERROR(e)
Definition: error.h:43
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:235
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
int i
Definition: input.c:407
static const AVOption fits_options[]
Definition: fitsdec.c:214
static int64_t is_image(AVFormatContext *s, FITSContext *fits, FITSHeader *header, AVBPrint *avbuf, uint64_t *data_size)
Parses header and checks that the current HDU contains image or not It also stores the header in the ...
Definition: fitsdec.c:79
static const AVClass fits_demuxer_class
Definition: fitsdec.c:219
AVInputFormat ff_fits_demuxer
Definition: fitsdec.c:226
static int fits_probe(const AVProbeData *p)
Definition: fitsdec.c:43
static int fits_read_header(AVFormatContext *s)
Definition: fitsdec.c:51
static int fits_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: fitsdec.c:144
#define FITS_BLOCK_SIZE
Definition: fitsdec.c:34
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4945
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
common internal API header
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
AVOptions.
#define AV_OPT_FLAG_DECODING_PARAM
a generic parameter which can be set by the user for demuxing or decoding
Definition: opt.h:279
static const uint8_t header[24]
Definition: sdr2.c:67
unsigned int pos
Definition: spdifenc.c:412
Describe the class of an AVClass context structure.
Definition: log.h:67
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
Format I/O context.
Definition: avformat.h:1232
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:645
AVOption.
Definition: opt.h:248
This structure stores compressed data.
Definition: packet.h:346
int stream_index
Definition: packet.h:371
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:375
int size
Definition: packet.h:370
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:362
uint8_t * data
Definition: packet.h:369
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
Rational number (pair of numerator and denominator).
Definition: rational.h:58
int num
Numerator.
Definition: rational.h:59
int den
Denominator.
Definition: rational.h:60
Stream structure.
Definition: avformat.h:873
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1038
int64_t pts
Definition: fitsdec.c:40
int first_image
Definition: fitsdec.c:39
AVRational framerate
Definition: fitsdec.c:38
Structure to store the header keywords in FITS file.
Definition: fits.h:43
#define av_freep(p)
int framerate
Definition: h264_levels.c:65
AVPacket * pkt
Definition: movenc.c:59
int size
const char * b
Definition: vf_curves.c:118