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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/intreadwrite.h"
28 #include "internal.h"
29 #include "libavutil/opt.h"
30 #include "libavcodec/fits.h"
31 #include "libavutil/bprint.h"
32 
33 #define FITS_BLOCK_SIZE 2880
34 
35 typedef struct FITSContext {
36  const AVClass *class;
39  int64_t pts;
40 } FITSContext;
41 
42 static int fits_probe(AVProbeData *p)
43 {
44  const uint8_t *b = p->buf;
45  if (!memcmp(b, "SIMPLE = T", 30))
46  return AVPROBE_SCORE_MAX - 1;
47  return 0;
48 }
49 
51 {
52  AVStream *st;
53  FITSContext * fits = s->priv_data;
54 
55  st = avformat_new_stream(s, NULL);
56  if (!st)
57  return AVERROR(ENOMEM);
58 
61 
62  avpriv_set_pts_info(st, 64, fits->framerate.den, fits->framerate.num);
63  fits->pts = 0;
64  fits->first_image = 1;
65  return 0;
66 }
67 
68 /**
69  * Parses header and checks that the current HDU contains image or not
70  * It also stores the header in the avbuf and stores the size of data part in data_size
71  * @param s pointer to AVFormat Context
72  * @param fits pointer to FITSContext
73  * @param header pointer to FITSHeader
74  * @param avbuf pointer to AVBPrint to store the header
75  * @param data_size to store the size of data part
76  * @return 1 if image found, 0 if any other extension and AVERROR_INVALIDDATA otherwise
77  */
79  AVBPrint *avbuf, uint64_t *data_size)
80 {
81  int i, ret, image = 0;
82  char buf[FITS_BLOCK_SIZE] = { 0 };
83  int64_t buf_size = 0, size = 0, t;
84 
85  do {
86  ret = avio_read(s->pb, buf, FITS_BLOCK_SIZE);
87  if (ret < 0) {
88  return ret;
89  } else if (ret < FITS_BLOCK_SIZE) {
90  return AVERROR_INVALIDDATA;
91  }
92 
94  ret = 0;
95  buf_size = 0;
96  while(!ret && buf_size < FITS_BLOCK_SIZE) {
97  ret = avpriv_fits_header_parse_line(s, header, buf + buf_size, NULL);
98  buf_size += 80;
99  }
100  } while (!ret);
101  if (ret < 0)
102  return ret;
103 
104  image = fits->first_image || header->image_extension;
105  fits->first_image = 0;
106 
107  if (header->groups) {
108  image = 0;
109  if (header->naxis > 1)
110  size = 1;
111  } else if (header->naxis) {
112  size = header->naxisn[0];
113  } else {
114  image = 0;
115  }
116 
117  for (i = 1; i < header->naxis; i++) {
118  if(size && header->naxisn[i] > UINT64_MAX / size)
119  return AVERROR_INVALIDDATA;
120  size *= header->naxisn[i];
121  }
122 
123  if(header->pcount > UINT64_MAX - size)
124  return AVERROR_INVALIDDATA;
125  size += header->pcount;
126 
127  t = (abs(header->bitpix) >> 3) * ((int64_t) header->gcount);
128  if(size && t > UINT64_MAX / size)
129  return AVERROR_INVALIDDATA;
130  size *= t;
131 
132  if (!size) {
133  image = 0;
134  } else {
135  if(FITS_BLOCK_SIZE - 1 > UINT64_MAX - size)
136  return AVERROR_INVALIDDATA;
138  }
139  *data_size = size;
140  return image;
141 }
142 
144 {
145  int64_t pos, ret;
146  uint64_t size;
147  FITSContext *fits = s->priv_data;
149  AVBPrint avbuf;
150  char *buf;
151 
152  if (fits->first_image) {
154  } else {
156  }
157 
159  while ((ret = is_image(s, fits, &header, &avbuf, &size)) == 0) {
160  pos = avio_skip(s->pb, size);
161  if (pos < 0)
162  return pos;
163 
164  av_bprint_finalize(&avbuf, NULL);
167  }
168  if (ret < 0)
169  goto fail;
170 
171  if (!av_bprint_is_complete(&avbuf)) {
172  ret = AVERROR(ENOMEM);
173  goto fail;
174  }
175 
176  // Header is sent with the first line removed...
177  ret = av_new_packet(pkt, avbuf.len - 80 + size);
178  if (ret < 0)
179  goto fail;
180 
181  pkt->stream_index = 0;
182  pkt->flags |= AV_PKT_FLAG_KEY;
183 
184  ret = av_bprint_finalize(&avbuf, &buf);
185  if (ret < 0) {
186  av_packet_unref(pkt);
187  return ret;
188  }
189 
190  memcpy(pkt->data, buf + 80, avbuf.len - 80);
191  pkt->size = avbuf.len - 80;
192  av_freep(&buf);
193  ret = avio_read(s->pb, pkt->data + pkt->size, size);
194  if (ret < 0) {
195  av_packet_unref(pkt);
196  return ret;
197  }
198 
199  pkt->size += ret;
200  pkt->pts = fits->pts;
201  fits->pts++;
202 
203  return 0;
204 
205 fail:
206  av_bprint_finalize(&avbuf, NULL);
207  return ret;
208 }
209 
210 static const AVOption fits_options[] = {
211  { "framerate", "set the framerate", offsetof(FITSContext, framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "1"}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM},
212  { NULL },
213 };
214 
215 static const AVClass fits_demuxer_class = {
216  .class_name = "FITS demuxer",
217  .item_name = av_default_item_name,
218  .option = fits_options,
219  .version = LIBAVUTIL_VERSION_INT,
220 };
221 
223  .name = "fits",
224  .long_name = NULL_IF_CONFIG_SMALL("Flexible Image Transport System"),
225  .priv_data_size = sizeof(FITSContext),
229  .priv_class = &fits_demuxer_class,
230  .raw_codec_id = AV_CODEC_ID_FITS,
231 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
AVOption.
Definition: opt.h:246
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:78
#define LIBAVUTIL_VERSION_INT
Definition: version.h:86
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:4737
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:4152
int num
Numerator.
Definition: rational.h:59
static int fits_probe(AVProbeData *p)
Definition: fitsdec.c:42
int size
Definition: avcodec.h:1680
const char * b
Definition: vf_curves.c:113
int image_extension
Definition: fits.h:55
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:329
static AVPacket pkt
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
Definition: bprint.c:235
Format I/O context.
Definition: avformat.h:1349
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
uint8_t
int naxis
Definition: fits.h:49
int first_image
Definition: fitsdec.c:38
AVOptions.
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4367
void av_bprint_append_data(AVBPrint *buf, const char *data, unsigned size)
Append data to a print buffer.
Definition: bprint.c:158
uint8_t * data
Definition: avcodec.h:1679
ptrdiff_t size
Definition: opengl_enc.c:101
static const uint8_t header[24]
Definition: sdr2.c:67
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:637
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1711
#define FITS_BLOCK_SIZE
Definition: fitsdec.c:33
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:86
static int fits_read_header(AVFormatContext *s)
Definition: fitsdec.c:50
#define AV_BPRINT_SIZE_UNLIMITED
av_default_item_name
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:179
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
Definition: bprint.c:69
Structure to store the header keywords in FITS file.
Definition: fits.h:43
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:4148
#define fail()
Definition: checkasm.h:109
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1685
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:463
int avpriv_fits_header_init(FITSHeader *header, FITSHeaderState state)
Initialize a single header line.
Definition: fits.c:26
static int fits_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: fitsdec.c:143
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
static int av_bprint_is_complete(const AVBPrint *buf)
Test if the print buffer is complete (not truncated).
Definition: bprint.h:185
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:528
Stream structure.
Definition: avformat.h:889
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
int bitpix
Definition: fits.h:46
AVRational framerate
Definition: fitsdec.c:37
AVIOContext * pb
I/O context.
Definition: avformat.h:1391
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
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:618
int naxisn[999]
Definition: fits.h:50
void * buf
Definition: avisynth_c.h:690
int64_t pts
Definition: fitsdec.c:39
Describe the class of an AVClass context structure.
Definition: log.h:67
Rational number (pair of numerator and denominator).
Definition: rational.h:58
#define AV_OPT_FLAG_DECODING_PARAM
a generic parameter which can be set by the user for demuxing or decoding
Definition: opt.h:277
static const AVClass fits_demuxer_class
Definition: fitsdec.c:215
offset must point to AVRational
Definition: opt.h:236
int pcount
Definition: fits.h:51
This structure contains the data a format has to probe a file.
Definition: avformat.h:461
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:473
int den
Denominator.
Definition: rational.h:60
void * priv_data
Format private data.
Definition: avformat.h:1377
int groups
Definition: fits.h:53
static const AVOption fits_options[]
Definition: fitsdec.c:210
#define av_freep(p)
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:664
AVCodecParameters * codecpar
Definition: avformat.h:1252
AVInputFormat ff_fits_demuxer
Definition: fitsdec.c:222
int stream_index
Definition: avcodec.h:1681
int gcount
Definition: fits.h:52
This structure stores compressed data.
Definition: avcodec.h:1656
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1672