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 "demux.h"
28 #include "internal.h"
29 #include "libavutil/opt.h"
30 #include "libavcodec/fits.h"
31 
32 #define FITS_BLOCK_SIZE 2880
33 
34 typedef struct FITSContext {
35  const AVClass *class;
38 } FITSContext;
39 
40 static int fits_probe(const AVProbeData *p)
41 {
42  const uint8_t *b = p->buf;
43  if (!memcmp(b, "SIMPLE = T", 30))
44  return AVPROBE_SCORE_MAX - 1;
45  return 0;
46 }
47 
49 {
50  AVStream *st;
51  FITSContext * fits = s->priv_data;
52 
53  st = avformat_new_stream(s, NULL);
54  if (!st)
55  return AVERROR(ENOMEM);
56 
59 
60  avpriv_set_pts_info(st, 64, fits->framerate.den, fits->framerate.num);
61  fits->first_image = 1;
62  return 0;
63 }
64 
65 /**
66  * Parses header and checks that the current HDU contains image or not
67  * It also stores the header in the avbuf and stores the size of data part in data_size
68  * @param s pointer to AVFormat Context
69  * @param fits pointer to FITSContext
70  * @param header pointer to FITSHeader
71  * @param pkt pointer to AVPacket to store the header
72  * @param data_size to store the size of data part
73  * @return 1 if image found, 0 if any other extension and AVERROR code otherwise
74  */
76  AVPacket *pkt, uint64_t *data_size)
77 {
78  int i, ret, image = 0;
79  int64_t size = 0, t;
80 
81  do {
82  const uint8_t *buf, *buf_end;
84  if (ret < 0) {
85  return ret;
86  } else if (ret < FITS_BLOCK_SIZE) {
87  return AVERROR_INVALIDDATA;
88  }
89 
90  ret = 0;
91  buf_end = pkt->data + pkt->size;
92  buf = buf_end - FITS_BLOCK_SIZE;
93  while(!ret && buf < buf_end) {
95  buf += 80;
96  }
97  } while (!ret);
98  if (ret < 0)
99  return ret;
100 
101  image = fits->first_image || header->image_extension;
102  fits->first_image = 0;
103 
104  if (header->groups) {
105  image = 0;
106  if (header->naxis > 1)
107  size = 1;
108  } else if (header->naxis) {
109  size = header->naxisn[0];
110  } else {
111  image = 0;
112  }
113 
114  for (i = 1; i < header->naxis; i++) {
115  if(size && header->naxisn[i] > UINT64_MAX / size)
116  return AVERROR_INVALIDDATA;
117  size *= header->naxisn[i];
118  }
119 
120  if(header->pcount > UINT64_MAX - size)
121  return AVERROR_INVALIDDATA;
122  size += header->pcount;
123 
124  t = (abs(header->bitpix) >> 3) * ((int64_t) header->gcount);
125  if(size && t > INT64_MAX / size)
126  return AVERROR_INVALIDDATA;
127  size *= t;
128 
129  if (!size) {
130  image = 0;
131  } else {
132  if(FITS_BLOCK_SIZE - 1 > INT64_MAX - size)
133  return AVERROR_INVALIDDATA;
135  }
136  *data_size = size;
137  return image;
138 }
139 
141 {
142  uint64_t size;
143  FITSContext *fits = s->priv_data;
145  int ret;
146 
147  if (fits->first_image) {
149  } else {
151  }
152 
153  while ((ret = is_image(s, fits, &header, pkt, &size)) == 0) {
154  int64_t pos = avio_skip(s->pb, size);
155  if (pos < 0)
156  return pos;
157 
160  }
161  if (ret < 0)
162  return ret;
163 
164  pkt->stream_index = 0;
166  pkt->duration = 1;
167  // Header is sent with the first line removed...
168  pkt->data += 80;
169  pkt->size -= 80;
170 
171  if (size > INT_MAX - AV_INPUT_BUFFER_PADDING_SIZE - pkt->size)
172  return AVERROR(ERANGE);
173 
174  ret = av_append_packet(s->pb, pkt, size);
175  if (ret < 0)
176  return ret;
177 
178  return 0;
179 }
180 
181 static const AVOption fits_options[] = {
182  { "framerate", "set the framerate", offsetof(FITSContext, framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "1"}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM},
183  { NULL },
184 };
185 
186 static const AVClass fits_demuxer_class = {
187  .class_name = "FITS demuxer",
188  .item_name = av_default_item_name,
189  .option = fits_options,
190  .version = LIBAVUTIL_VERSION_INT,
191  .category = AV_CLASS_CATEGORY_DEMUXER,
192 };
193 
195  .p.name = "fits",
196  .p.long_name = NULL_IF_CONFIG_SMALL("Flexible Image Transport System"),
197  .p.priv_class = &fits_demuxer_class,
198  .p.flags = AVFMT_NOTIMESTAMPS,
199  .priv_data_size = sizeof(FITSContext),
203 };
av_packet_unref
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: packet.c:427
fits_demuxer_class
static const AVClass fits_demuxer_class
Definition: fitsdec.c:186
AVERROR
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
opt.h
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
AV_OPT_TYPE_VIDEO_RATE
@ AV_OPT_TYPE_VIDEO_RATE
offset must point to AVRational
Definition: opt.h:258
AVFMT_NOTIMESTAMPS
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:479
FITSContext
Definition: fitsdec.c:43
AVPacket::data
uint8_t * data
Definition: packet.h:520
AVOption
AVOption.
Definition: opt.h:357
b
#define b
Definition: input.c:41
is_image
static int is_image(AVFormatContext *s, FITSContext *fits, FITSHeader *header, AVPacket *pkt, 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:75
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:538
FITSContext::framerate
AVRational framerate
Definition: fitsdec.c:36
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:575
STATE_XTENSION
@ STATE_XTENSION
Definition: fits.h:31
fits.h
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:463
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: avformat.c:853
fits_options
static const AVOption fits_options[]
Definition: fitsdec.c:181
avpriv_fits_header_parse_line
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:113
fits_probe
static int fits_probe(const AVProbeData *p)
Definition: fitsdec.c:40
AVRational::num
int num
Numerator.
Definition: rational.h:59
pkt
AVPacket * pkt
Definition: movenc.c:60
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:42
s
#define s(width, name)
Definition: cbs_vp9.c:198
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:553
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:453
AV_CLASS_CATEGORY_DEMUXER
@ AV_CLASS_CATEGORY_DEMUXER
Definition: log.h:33
AVFormatContext
Format I/O context.
Definition: avformat.h:1255
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:766
framerate
float framerate
Definition: av1_levels.c:29
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:550
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
AV_CODEC_ID_FITS
@ AV_CODEC_ID_FITS
Definition: codec_id.h:286
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:237
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
abs
#define abs(x)
Definition: cuda_runtime.h:35
fits_read_packet
static int fits_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: fitsdec.c:140
AVPacket::size
int size
Definition: packet.h:521
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:94
size
int size
Definition: twinvq_data.h:10344
fits_read_header
static int fits_read_header(AVFormatContext *s)
Definition: fitsdec.c:48
ff_fits_demuxer
const FFInputFormat ff_fits_demuxer
Definition: fitsdec.c:194
FFInputFormat::p
AVInputFormat p
The public AVInputFormat.
Definition: demux.h:41
header
static const uint8_t header[24]
Definition: sdr2.c:68
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:526
avpriv_fits_header_init
int avpriv_fits_header_init(FITSHeader *header, FITSHeaderState state)
Initialize a single header line.
Definition: fits.c:31
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
STATE_SIMPLE
@ STATE_SIMPLE
Definition: fits.h:30
demux.h
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:743
AVClass::class_name
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:71
av_append_packet
int av_append_packet(AVIOContext *s, AVPacket *pkt, int size)
Read data and append it to the current content of the AVPacket.
Definition: utils.c:107
pos
unsigned int pos
Definition: spdifenc.c:414
AV_INPUT_BUFFER_PADDING_SIZE
#define AV_INPUT_BUFFER_PADDING_SIZE
Definition: defs.h:40
FITSContext::first_image
int first_image
Definition: fitsdec.c:37
AVRational::den
int den
Denominator.
Definition: rational.h:60
FITSHeader
Structure to store the header keywords in FITS file.
Definition: fits.h:43
AVPacket::stream_index
int stream_index
Definition: packet.h:522
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:318
AV_OPT_FLAG_DECODING_PARAM
#define AV_OPT_FLAG_DECODING_PARAM
A generic parameter which can be set by the user for demuxing or decoding.
Definition: opt.h:284
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:30
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:497
FFInputFormat
Definition: demux.h:37
FITS_BLOCK_SIZE
#define FITS_BLOCK_SIZE
Definition: fitsdec.c:32
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61