FFmpeg: libavformat/ifv.c Source File

FFmpeg
ifv.c
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1 /*
2  * IFV demuxer
3  *
4  * Copyright (c) 2019 Swaraj Hota
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include "libavutil/channel_layout.h"
24 #include "libavutil/dict_internal.h"
25 #include "avformat.h"
26 #include "internal.h"
27 #include "avio_internal.h"
28 
29  typedef struct IFVContext {
30   uint32_t next_video_index;
31   uint32_t next_audio_index;
32   uint32_t total_vframes;
33   uint32_t total_aframes;
34 
35   int width, height;
36   int is_audio_present;
37   int sample_rate;
38 
39   int video_stream_index;
40   int audio_stream_index;
41 } IFVContext;
42 
43  static int ifv_probe(const AVProbeData *p)
44 {
45  static const uint8_t ifv_magic[] = {0x11, 0xd2, 0xd3, 0xab, 0xba, 0xa9,
46  0xcf, 0x11, 0x8e, 0xe6, 0x00, 0xc0, 0x0c, 0x20, 0x53, 0x65, 0x44};
47 
48  if (!memcmp(p->buf, ifv_magic, sizeof(ifv_magic)))
49  return AVPROBE_SCORE_MAX;
50 
51  return 0;
52 }
53 
54  static int read_index(AVFormatContext *s,
55  enum AVMediaType frame_type,
56  uint32_t start_index)
57 {
58  IFVContext *ifv = s->priv_data;
59  AVStream *st;
60  int64_t pos, size, timestamp;
61  uint32_t end_index, i;
62  int ret;
63 
64  if (frame_type == AVMEDIA_TYPE_VIDEO) {
65  end_index = ifv->total_vframes;
66  st = s->streams[ifv->video_stream_index];
67  } else {
68  end_index = ifv->total_aframes;
69  st = s->streams[ifv->audio_stream_index];
70  }
71 
72  for (i = start_index; i < end_index; i++) {
73  if (avio_feof(s->pb))
74  return AVERROR_EOF;
75  pos = avio_rl32(s->pb);
76  size = avio_rl32(s->pb);
77 
78  avio_skip(s->pb, 8);
79  timestamp = avio_rl32(s->pb);
80 
81  ret = av_add_index_entry(st, pos, timestamp, size, 0, 0);
82  if (ret < 0)
83  return ret;
84 
85  avio_skip(s->pb, frame_type == AVMEDIA_TYPE_VIDEO ? 8: 4);
86  }
87 
88  return 0;
89 }
90 
91  static int parse_header(AVFormatContext *s)
92 {
93  IFVContext *ifv = s->priv_data;
94  uint32_t aud_magic;
95  uint32_t vid_magic;
96 
97  avio_skip(s->pb, 0x34);
98  avpriv_dict_set_timestamp(&s->metadata, "creation_time", avio_rl32(s->pb) * 1000000LL);
99  avio_skip(s->pb, 0x24);
100 
101  ifv->width = avio_rl16(s->pb);
102  ifv->height = avio_rl16(s->pb);
103 
104  avio_skip(s->pb, 0x8);
105  vid_magic = avio_rl32(s->pb);
106 
107  if (vid_magic != MKTAG('H','2','6','4'))
108  avpriv_request_sample(s, "Unknown video codec %x", vid_magic);
109 
110  avio_skip(s->pb, 0x2c);
111  ifv->sample_rate = avio_rl32(s->pb);
112  aud_magic = avio_rl32(s->pb);
113 
114  if (aud_magic == MKTAG('G','R','A','W')) {
115  ifv->is_audio_present = 1;
116  } else if (aud_magic == MKTAG('P','C','M','U')) {
117  ifv->is_audio_present = 0;
118  } else {
119  avpriv_request_sample(s, "Unknown audio codec %x", aud_magic);
120  }
121 
122  avio_skip(s->pb, 0x44);
123  ifv->total_vframes = avio_rl32(s->pb);
124  ifv->total_aframes = avio_rl32(s->pb);
125 
126  return 0;
127 }
128 
129  static int ifv_read_header(AVFormatContext *s)
130 {
131  IFVContext *ifv = s->priv_data;
132  AVStream *st;
133  int ret;
134 
135  ret = parse_header(s);
136  if (ret < 0)
137  return ret;
138 
139  st = avformat_new_stream(s, NULL);
140  if (!st)
141  return AVERROR(ENOMEM);
142 
143  st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
144  st->codecpar->codec_id = AV_CODEC_ID_H264;
145  st->codecpar->width = ifv->width;
146  st->codecpar->height = ifv->height;
147  st->start_time = 0;
148  ifv->video_stream_index = st->index;
149 
150  avpriv_set_pts_info(st, 32, 1, 1000);
151 
152  if (ifv->is_audio_present) {
153  st = avformat_new_stream(s, NULL);
154  if (!st)
155  return AVERROR(ENOMEM);
156 
157  st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
158  st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE;
159  st->codecpar->ch_layout = (AVChannelLayout)AV_CHANNEL_LAYOUT_MONO;
160  st->codecpar->sample_rate = ifv->sample_rate;
161  ifv->audio_stream_index = st->index;
162 
163  avpriv_set_pts_info(st, 32, 1, 1000);
164  }
165 
166  /*read video index*/
167  avio_seek(s->pb, 0xf8, SEEK_SET);
168 
169  ret = read_index(s, AVMEDIA_TYPE_VIDEO, 0);
170  if (ret < 0)
171  return ret;
172 
173  if (ifv->is_audio_present) {
174  /*read audio index*/
175  avio_seek(s->pb, 0x14918, SEEK_SET);
176 
177  ret = read_index(s, AVMEDIA_TYPE_AUDIO, 0);
178  if (ret < 0)
179  return ret;
180  }
181 
182  ifv->next_video_index = 0;
183  ifv->next_audio_index = 0;
184 
185  return 0;
186 }
187 
188  static int ifv_read_packet(AVFormatContext *s, AVPacket *pkt)
189 {
190  IFVContext *ifv = s->priv_data;
191  AVIndexEntry *ev, *ea, *e_next;
192  int ret;
193 
194  ev = ea = e_next = NULL;
195 
196  if (ifv->next_video_index < ifv->total_vframes) {
197  AVStream *const st = s->streams[ifv->video_stream_index];
198  FFStream *const sti = ffstream(st);
199 
200  if (ifv->next_video_index < sti->nb_index_entries)
201  e_next = ev = &sti->index_entries[ifv->next_video_index];
202  }
203 
204  if (ifv->is_audio_present &&
205  ifv->next_audio_index < ifv->total_aframes) {
206  AVStream *const st = s->streams[ifv->audio_stream_index];
207  FFStream *const sti = ffstream(st);
208 
209  if (ifv->next_audio_index < sti->nb_index_entries) {
210  ea = &sti->index_entries[ifv->next_audio_index];
211  if (!ev || ea->timestamp < ev->timestamp)
212  e_next = ea;
213  }
214  }
215 
216  if (!ev) {
217  uint64_t vframes, aframes;
218  if (ifv->is_audio_present && !ea) {
219  /*read new video and audio indexes*/
220 
221  ifv->next_video_index = ifv->total_vframes;
222  ifv->next_audio_index = ifv->total_aframes;
223 
224  avio_skip(s->pb, 0x1c);
225  vframes = ifv->total_vframes + (uint64_t)avio_rl32(s->pb);
226  aframes = ifv->total_aframes + (uint64_t)avio_rl32(s->pb);
227  if (vframes > INT_MAX || aframes > INT_MAX)
228  return AVERROR_INVALIDDATA;
229  ifv->total_vframes = vframes;
230  ifv->total_aframes = aframes;
231  avio_skip(s->pb, 0xc);
232 
233  if (avio_feof(s->pb))
234  return AVERROR_EOF;
235 
236  ret = read_index(s, AVMEDIA_TYPE_VIDEO, ifv->next_video_index);
237  if (ret < 0)
238  return ret;
239 
240  ret = read_index(s, AVMEDIA_TYPE_AUDIO, ifv->next_audio_index);
241  if (ret < 0)
242  return ret;
243 
244  return 0;
245 
246  } else if (!ifv->is_audio_present) {
247  /*read new video index*/
248 
249  ifv->next_video_index = ifv->total_vframes;
250 
251  avio_skip(s->pb, 0x1c);
252  vframes = ifv->total_vframes + (uint64_t)avio_rl32(s->pb);
253  if (vframes > INT_MAX)
254  return AVERROR_INVALIDDATA;
255  ifv->total_vframes = vframes;
256  avio_skip(s->pb, 0x10);
257 
258  if (avio_feof(s->pb))
259  return AVERROR_EOF;
260 
261  ret = read_index(s, AVMEDIA_TYPE_VIDEO, ifv->next_video_index);
262  if (ret < 0)
263  return ret;
264 
265  return 0;
266  }
267  }
268 
269  if (!e_next) return AVERROR_EOF;
270 
271  avio_seek(s->pb, e_next->pos, SEEK_SET);
272  ret = av_get_packet(s->pb, pkt, e_next->size);
273  if (ret < 0)
274  return ret;
275 
276  if (e_next == ev) {
277  ifv->next_video_index++;
278  pkt->stream_index = ifv->video_stream_index;
279  } else {
280  ifv->next_audio_index++;
281  pkt->stream_index = ifv->audio_stream_index;
282  }
283 
284  pkt->pts = e_next->timestamp;
285  pkt->pos = e_next->pos;
286 
287  return 0;
288 }
289 
290  static int ifv_read_seek(AVFormatContext *s, int stream_index, int64_t ts, int flags)
291 {
292  IFVContext *ifv = s->priv_data;
293 
294  for (unsigned i = 0; i < s->nb_streams; i++) {
295  int index = av_index_search_timestamp(s->streams[i], ts, AVSEEK_FLAG_ANY);
296  if (index < 0) {
297  ifv->next_video_index = ifv->total_vframes - 1;
298  ifv->next_audio_index = ifv->total_aframes - 1;
299  return 0;
300  }
301 
302  if (i == ifv->video_stream_index) {
303  ifv->next_video_index = index;
304  } else {
305  ifv->next_audio_index = index;
306  }
307  }
308 
309  return 0;
310 }
311 
312  const AVInputFormat ff_ifv_demuxer = {
313  .name = "ifv",
314  .long_name = NULL_IF_CONFIG_SMALL("IFV CCTV DVR"),
315  .priv_data_size = sizeof(IFVContext),
316  .extensions = "ifv",
317  .read_probe = ifv_probe,
318  .read_header = ifv_read_header,
319  .read_packet = ifv_read_packet,
320  .read_seek = ifv_read_seek,
321 };
AV_CODEC_ID_PCM_S16LE
@ AV_CODEC_ID_PCM_S16LE
Definition: codec_id.h:326
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
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
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
read_index
static int read_index(AVFormatContext *s, enum AVMediaType frame_type, uint32_t start_index)
Definition: ifv.c:54
IFVContext::video_stream_index
int video_stream_index
Definition: ifv.c:39
dict_internal.h
IFVContext::audio_stream_index
int audio_stream_index
Definition: ifv.c:40
IFVContext::next_audio_index
uint32_t next_audio_index
Definition: ifv.c:31
IFVContext::total_vframes
uint32_t total_vframes
Definition: ifv.c:32
AVIndexEntry
Definition: avformat.h:697
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:771
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:413
IFVContext::next_video_index
uint32_t next_video_index
Definition: ifv.c:30
AVSEEK_FLAG_ANY
#define AVSEEK_FLAG_ANY
seek to any frame, even non-keyframes
Definition: avformat.h:2196
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:151
av_add_index_entry
int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp, int size, int distance, int flags)
Add an index entry into a sorted list.
Definition: seek.c:120
IFVContext::is_audio_present
int is_audio_present
Definition: ifv.c:36
avio_rl16
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:735
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
s
#define s(width, name)
Definition: cbs_vp9.c:256
parse_header
static int parse_header(AVFormatContext *s)
Definition: ifv.c:91
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
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:128
AVIndexEntry::size
int size
Definition: avformat.h:708
AVIndexEntry::timestamp
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:699
ifv_read_seek
static int ifv_read_seek(AVFormatContext *s, int stream_index, int64_t ts, int flags)
Definition: ifv.c:290
AV_CODEC_ID_H264
@ AV_CODEC_ID_H264
Definition: codec_id.h:79
ifv_read_packet
static int ifv_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: ifv.c:188
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
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:545
NULL
#define NULL
Definition: coverity.c:32
ifv_probe
static int ifv_probe(const AVProbeData *p)
Definition: ifv.c:43
FFStream::nb_index_entries
int nb_index_entries
Definition: internal.h:253
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:213
index
int index
Definition: gxfenc.c:89
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:178
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:751
AVMediaType
AVMediaType
Definition: avutil.h:199
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
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:301
FFStream
Definition: internal.h:196
size
int size
Definition: twinvq_data.h:10344
ifv_read_header
static int ifv_read_header(AVFormatContext *s)
Definition: ifv.c:129
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
frame_type
frame_type
Definition: jpeg2000_parser.c:31
avio_internal.h
AVCodecParameters::height
int height
Definition: codec_par.h:129
av_get_packet
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:102
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:838
IFVContext
Definition: ifv.c:29
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:252
pos
unsigned int pos
Definition: spdifenc.c:413
avformat.h
IFVContext::width
int width
Definition: ifv.c:35
ff_ifv_demuxer
const AVInputFormat ff_ifv_demuxer
Definition: ifv.c:312
AVStream::index
int index
stream index in AVFormatContext
Definition: avformat.h:844
channel_layout.h
IFVContext::total_aframes
uint32_t total_aframes
Definition: ifv.c:33
AVIndexEntry::pos
int64_t pos
Definition: avformat.h:698
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
FFStream::index_entries
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: internal.h:251
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:29
IFVContext::sample_rate
int sample_rate
Definition: ifv.c:37
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:36
AV_CHANNEL_LAYOUT_MONO
#define AV_CHANNEL_LAYOUT_MONO
Definition: channel_layout.h:368
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
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:394
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
MKTAG
#define MKTAG(a, b, c, d)
Definition: macros.h:55
AVStream::start_time
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:887
avpriv_dict_set_timestamp
int avpriv_dict_set_timestamp(AVDictionary **dict, const char *key, int64_t timestamp)
Set a dictionary value to an ISO-8601 compliant timestamp string.
Definition: dict.c:278
IFVContext::height
int height
Definition: ifv.c:35
av_index_search_timestamp
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: seek.c:240
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:367
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