FFmpeg
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(const 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
#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:85
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:4929
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3968
int num
Numerator.
Definition: rational.h:59
int size
Definition: avcodec.h:1481
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
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:334
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:1358
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.
static int fits_probe(const AVProbeData *p)
Definition: fitsdec.c:42
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4502
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:1480
ptrdiff_t size
Definition: opengl_enc.c:100
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:650
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1512
#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 i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define AV_BPRINT_SIZE_UNLIMITED
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
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:3964
#define fail()
Definition: checkasm.h:122
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1486
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
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
#define b
Definition: input.c:41
#define s(width, name)
Definition: cbs_vp9.c:257
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:530
Stream structure.
Definition: avformat.h:881
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:1400
#define abs(x)
Definition: cuda_runtime.h:35
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:599
int naxisn[999]
Definition: fits.h:50
void * buf
Definition: avisynth_c.h:766
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:446
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
int den
Denominator.
Definition: rational.h:60
void * priv_data
Format private data.
Definition: avformat.h:1386
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:654
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
AVInputFormat ff_fits_demuxer
Definition: fitsdec.c:222
int stream_index
Definition: avcodec.h:1482
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
int gcount
Definition: fits.h:52
This structure stores compressed data.
Definition: avcodec.h:1457
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1473