FFmpeg: libavformat/fitsdec.c Source File

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/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;
38   AVRational framerate;
39   int first_image;
40   int64_t pts;
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 
51  static int fits_read_header(AVFormatContext *s)
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 
60  st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
61  st->codecpar->codec_id = AV_CODEC_ID_FITS;
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  */
79  static int64_t is_image(AVFormatContext *s, FITSContext *fits, FITSHeader *header,
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 
94  av_bprint_append_data(avbuf, buf, FITS_BLOCK_SIZE);
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;
138  size = ((size + FITS_BLOCK_SIZE - 1) / FITS_BLOCK_SIZE) * FITS_BLOCK_SIZE;
139  }
140  *data_size = size;
141  return image;
142 }
143 
144  static int fits_read_packet(AVFormatContext *s, AVPacket *pkt)
145 {
146  int64_t pos, ret;
147  uint64_t size;
148  FITSContext *fits = s->priv_data;
149  FITSHeader header;
150  AVBPrint avbuf;
151  char *buf;
152 
153  if (fits->first_image) {
154  avpriv_fits_header_init(&header, STATE_SIMPLE);
155  } else {
156  avpriv_fits_header_init(&header, STATE_XTENSION);
157  }
158 
159  av_bprint_init(&avbuf, FITS_BLOCK_SIZE, AV_BPRINT_SIZE_UNLIMITED);
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 
166  av_bprint_init(&avbuf, FITS_BLOCK_SIZE, AV_BPRINT_SIZE_UNLIMITED);
167  avpriv_fits_header_init(&header, STATE_XTENSION);
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;
188  pkt->flags |= AV_PKT_FLAG_KEY;
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 
226  const AVInputFormat ff_fits_demuxer = {
227  .name = "fits",
228  .long_name = NULL_IF_CONFIG_SMALL("Flexible Image Transport System"),
229  .priv_data_size = sizeof(FITSContext),
230  .read_probe = fits_probe,
231  .read_header = fits_read_header,
232  .read_packet = fits_read_packet,
233  .priv_class = &fits_demuxer_class,
234  .raw_codec_id = AV_CODEC_ID_FITS,
235 };
AV_BPRINT_SIZE_UNLIMITED
#define AV_BPRINT_SIZE_UNLIMITED
fits_demuxer_class
static const AVClass fits_demuxer_class
Definition: fitsdec.c:219
av_bprint_is_complete
static int av_bprint_is_complete(const AVBPrint *buf)
Test if the print buffer is complete (not truncated).
Definition: bprint.h:215
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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: options.c:243
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:58
av_bprint_init
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
Definition: bprint.c:69
AV_OPT_TYPE_VIDEO_RATE
@ AV_OPT_TYPE_VIDEO_RATE
offset must point to AVRational
Definition: opt.h:238
FITSContext
Definition: fitsdec.c:43
AVPacket::data
uint8_t * data
Definition: packet.h:374
AVOption
AVOption.
Definition: opt.h:251
b
#define b
Definition: input.c:41
FITSContext::framerate
AVRational framerate
Definition: fitsdec.c:38
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:429
STATE_XTENSION
@ STATE_XTENSION
Definition: fits.h:31
fits.h
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:463
framerate
int framerate
Definition: h264_levels.c:65
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:771
fits_options
static const AVOption fits_options[]
Definition: fitsdec.c:214
fail
#define fail()
Definition: checkasm.h:134
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:43
FITSContext::pts
int64_t pts
Definition: fitsdec.c:40
AVRational::num
int num
Numerator.
Definition: rational.h:59
ff_fits_demuxer
const AVInputFormat ff_fits_demuxer
Definition: fitsdec.c:226
avassert.h
pkt
AVPacket * pkt
Definition: movenc.c:59
AVInputFormat
Definition: avformat.h:546
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:41
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:256
av_new_packet
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:97
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:551
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:453
is_image
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
av_assert0
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
AVFormatContext
Format I/O context.
Definition: avformat.h:1104
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:861
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:545
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:289
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:144
AVPacket::size
int size
Definition: packet.h:375
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:115
av_bprint_finalize
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
Definition: bprint.c:235
size
int size
Definition: twinvq_data.h:10344
fits_read_header
static int fits_read_header(AVFormatContext *s)
Definition: fitsdec.c:51
header
static const uint8_t header[24]
Definition: sdr2.c:67
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:380
avpriv_fits_header_init
int avpriv_fits_header_init(FITSHeader *header, FITSHeaderState state)
Initialize a single header line.
Definition: fits.c:31
bprint.h
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:367
STATE_SIMPLE
@ STATE_SIMPLE
Definition: fits.h:30
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:282
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:838
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
pos
unsigned int pos
Definition: spdifenc.c:413
FITSContext::first_image
int first_image
Definition: fitsdec.c:39
AVRational::den
int den
Denominator.
Definition: rational.h:60
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:633
FITSHeader
Structure to store the header keywords in FITS file.
Definition: fits.h:43
AVPacket::stream_index
int stream_index
Definition: packet.h:376
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:339
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:29
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:62
AVPacket
This structure stores compressed data.
Definition: packet.h:351
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
FITS_BLOCK_SIZE
#define FITS_BLOCK_SIZE
Definition: fitsdec.c:34
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
av_bprint_append_data
void av_bprint_append_data(AVBPrint *buf, const char *data, unsigned size)
Append data to a print buffer.
Definition: bprint.c:158
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