FFmpeg
dhav.c
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1 /*
2  * DHAV demuxer
3  *
4  * Copyright (c) 2018 Paul B Mahol
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/parseutils.h"
24 #include "avio_internal.h"
25 #include "avformat.h"
26 #include "internal.h"
27 
28 typedef struct DHAVContext {
29  unsigned type;
30  unsigned subtype;
31  unsigned channel;
32  unsigned frame_subnumber;
33  unsigned frame_number;
34  unsigned date;
35  unsigned timestamp;
36  int width, height;
42 
45 } DHAVContext;
46 
47 typedef struct DHAVStream {
48  int64_t last_timestamp;
49  int64_t pts;
50 } DHAVStream;
51 
52 static int dhav_probe(const AVProbeData *p)
53 {
54  if (!memcmp(p->buf, "DAHUA", 5))
55  return AVPROBE_SCORE_MAX;
56 
57  if (memcmp(p->buf, "DHAV", 4))
58  return 0;
59 
60  if (p->buf[4] == 0xf0 ||
61  p->buf[4] == 0xf1 ||
62  p->buf[4] == 0xfc ||
63  p->buf[4] == 0xfd)
64  return AVPROBE_SCORE_MAX;
65  return 0;
66 }
67 
69 {
70  DHAVContext *dhav = s->priv_data;
71  uint8_t signature[5];
72 
73  ffio_ensure_seekback(s->pb, 5);
74  avio_read(s->pb, signature, sizeof(signature));
75  if (!memcmp(signature, "DAHUA", 5))
76  avio_skip(s->pb, 0x400 - 5);
77  else
78  avio_seek(s->pb, -5, SEEK_CUR);
79 
81  dhav->video_stream_index = -1;
82  dhav->audio_stream_index = -1;
83 
84  return 0;
85 }
86 
87 static int64_t get_pts(AVFormatContext *s, DHAVStream *st)
88 {
89  DHAVContext *dhav = s->priv_data;
90  /*
91  int year, month, day, hour, min, sec;
92  struct tm timeinfo;
93 
94  sec = dhav->date & 0x3F;
95  min = (dhav->date >> 6) & 0x3F;
96  hour = (dhav->date >> 12) & 0x1F;
97  day = (dhav->date >> 17) & 0x1F;
98  month = (dhav->date >> 22) & 0x0F;
99  year = ((dhav->date >> 26) & 0x3F) + 2000;
100 
101  timeinfo.tm_year = year - 1900;
102  timeinfo.tm_mon = month - 1;
103  timeinfo.tm_mday = day;
104  timeinfo.tm_hour = hour;
105  timeinfo.tm_min = min;
106  timeinfo.tm_sec = sec;*/
107 
108  if (st->last_timestamp == AV_NOPTS_VALUE) {
109  st->last_timestamp = dhav->timestamp;
110  }
111 
112  if (st->last_timestamp <= dhav->timestamp) {
113  st->pts += dhav->timestamp - st->last_timestamp;
114  } else {
115  st->pts += 65535 + dhav->timestamp - st->last_timestamp;
116  }
117 
118  st->last_timestamp = dhav->timestamp;
119 
120  return st->pts;
121 }
122 
123 static const uint32_t sample_rates[] = {
124  8000, 4000, 8000, 11025, 16000,
125  20000, 22050, 32000, 44100, 48000,
126  96000, 192000, 64000,
127 };
128 
130 {
131  DHAVContext *dhav = s->priv_data;
132  int index;
133 
134  while (length > 0) {
135  int type = avio_r8(s->pb);
136 
137  switch (type) {
138  case 0x80:
139  avio_skip(s->pb, 1);
140  dhav->width = 8 * avio_r8(s->pb);
141  dhav->height = 8 * avio_r8(s->pb);
142  length -= 4;
143  break;
144  case 0x81:
145  avio_skip(s->pb, 1);
146  dhav->video_codec = avio_r8(s->pb);
147  dhav->frame_rate = avio_r8(s->pb);
148  length -= 4;
149  break;
150  case 0x82:
151  avio_skip(s->pb, 3);
152  dhav->width = avio_rl16(s->pb);
153  dhav->height = avio_rl16(s->pb);
154  length -= 8;
155  break;
156  case 0x83:
157  dhav->audio_channels = avio_r8(s->pb);
158  dhav->audio_codec = avio_r8(s->pb);
159  index = avio_r8(s->pb);
160  if (index < FF_ARRAY_ELEMS(sample_rates)) {
161  dhav->sample_rate = sample_rates[index];
162  } else {
163  dhav->sample_rate = 8000;
164  }
165  length -= 4;
166  break;
167  case 0x88:
168  avio_skip(s->pb, 7);
169  length -= 8;
170  break;
171  case 0x8c:
172  avio_skip(s->pb, 1);
173  dhav->audio_channels = avio_r8(s->pb);
174  dhav->audio_codec = avio_r8(s->pb);
175  index = avio_r8(s->pb);
176  if (index < FF_ARRAY_ELEMS(sample_rates)) {
177  dhav->sample_rate = sample_rates[index];
178  } else {
179  dhav->sample_rate = 8000;
180  }
181  avio_skip(s->pb, 3);
182  length -= 8;
183  break;
184  case 0x91:
185  case 0x92:
186  case 0x93:
187  case 0x95:
188  case 0x9a:
189  case 0x9b: // sample aspect ratio
190  case 0xb3:
191  avio_skip(s->pb, 7);
192  length -= 8;
193  break;
194  case 0x84:
195  case 0x85:
196  case 0x8b:
197  case 0x94:
198  case 0x96:
199  case 0xa0:
200  case 0xb2:
201  case 0xb4:
202  avio_skip(s->pb, 3);
203  length -= 4;
204  break;
205  default:
206  av_log(s, AV_LOG_INFO, "Unknown type: %X, skipping rest of header.\n", type);
207  avio_skip(s->pb, length - 1);
208  length = 0;
209  }
210  }
211 
212  return 0;
213 }
214 
216 {
217  DHAVContext *dhav = s->priv_data;
218  unsigned frame_length, ext_length;
219  int64_t start, end;
220  int ret;
221 
222  start = avio_tell(s->pb);
223 
224  if (avio_feof(s->pb))
225  return AVERROR_EOF;
226 
227  if (avio_rl32(s->pb) != MKTAG('D','H','A','V'))
228  return AVERROR_INVALIDDATA;
229 
230  dhav->type = avio_r8(s->pb);
231  dhav->subtype = avio_r8(s->pb);
232  dhav->channel = avio_r8(s->pb);
233  dhav->frame_subnumber = avio_r8(s->pb);
234  dhav->frame_number = avio_rl32(s->pb);
235  frame_length = avio_rl32(s->pb);
236 
237  if (frame_length < 24)
238  return AVERROR_INVALIDDATA;
239  if (dhav->type == 0xf1) {
240  avio_skip(s->pb, frame_length - 16);
241  return 0;
242  }
243 
244  dhav->date = avio_rl32(s->pb);
245  dhav->timestamp = avio_rl16(s->pb);
246  ext_length = avio_r8(s->pb);
247  avio_skip(s->pb, 1); // checksum
248 
249  ret = parse_ext(s, ext_length);
250  if (ret < 0)
251  return ret;
252 
253  end = avio_tell(s->pb);
254 
255  return frame_length - 8 - (end - start);
256 }
257 
259 {
260  DHAVContext *dhav = s->priv_data;
261  int64_t start;
262  int ret;
263 
264  start = avio_tell(s->pb);
265 
266  while ((ret = read_chunk(s)) == 0)
267  ;
268 
269  if (ret < 0)
270  return ret;
271 
272  if (dhav->type == 0xfd && dhav->video_stream_index == -1) {
274  DHAVStream *dst;
275 
276  if (!st)
277  return AVERROR(ENOMEM);
278 
280  switch (dhav->video_codec) {
281  case 0x1: st->codecpar->codec_id = AV_CODEC_ID_MPEG4; break;
282  case 0x3: st->codecpar->codec_id = AV_CODEC_ID_MJPEG; break;
283  case 0x2:
284  case 0x4:
285  case 0x8: st->codecpar->codec_id = AV_CODEC_ID_H264; break;
286  case 0xc: st->codecpar->codec_id = AV_CODEC_ID_HEVC; break;
287  default: avpriv_request_sample(s, "Unknown video codec %X\n", dhav->video_codec);
288  }
289  st->codecpar->width = dhav->width;
290  st->codecpar->height = dhav->height;
291  st->avg_frame_rate.num = dhav->frame_rate;
292  st->avg_frame_rate.den = 1;
293  st->priv_data = dst = av_mallocz(sizeof(DHAVStream));
294  if (!st->priv_data)
295  return AVERROR(ENOMEM);
297  dhav->video_stream_index = st->index;
298 
299  avpriv_set_pts_info(st, 64, 1, 1000);
300  } else if (dhav->type == 0xf0 && dhav->audio_stream_index == -1) {
302  DHAVStream *dst;
303 
304  if (!st)
305  return AVERROR(ENOMEM);
306 
308  switch (dhav->audio_codec) {
309  case 0x07: st->codecpar->codec_id = AV_CODEC_ID_PCM_S8; break;
310  case 0x0c: st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE; break;
311  case 0x10: st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE; break;
312  case 0x0a: st->codecpar->codec_id = AV_CODEC_ID_PCM_MULAW; break;
313  case 0x16: st->codecpar->codec_id = AV_CODEC_ID_PCM_MULAW; break;
314  case 0x0e: st->codecpar->codec_id = AV_CODEC_ID_PCM_ALAW; break;
315  case 0x1a: st->codecpar->codec_id = AV_CODEC_ID_AAC; break;
316  case 0x1f: st->codecpar->codec_id = AV_CODEC_ID_MP2; break;
317  case 0x21: st->codecpar->codec_id = AV_CODEC_ID_MP3; break;
318  case 0x0d: st->codecpar->codec_id = AV_CODEC_ID_ADPCM_MS; break;
319  default: avpriv_request_sample(s, "Unknown audio codec %X\n", dhav->audio_codec);
320  }
321  st->codecpar->channels = dhav->audio_channels;
322  st->codecpar->sample_rate = dhav->sample_rate;
323  st->priv_data = dst = av_mallocz(sizeof(DHAVStream));
324  if (!st->priv_data)
325  return AVERROR(ENOMEM);
327  dhav->audio_stream_index = st->index;
328 
329  avpriv_set_pts_info(st, 64, 1, 1000);
330  }
331 
332  ret = av_get_packet(s->pb, pkt, ret);
333  if (ret < 0)
334  return ret;
335  pkt->stream_index = dhav->type == 0xf0 ? dhav->audio_stream_index : dhav->video_stream_index;
336  if (dhav->type != 0xfc)
337  pkt->flags |= AV_PKT_FLAG_KEY;
338  if (pkt->stream_index >= 0)
339  pkt->pts = get_pts(s, s->streams[pkt->stream_index]->priv_data);
340  pkt->duration = 1;
341  pkt->pos = start;
342  if (avio_rl32(s->pb) != MKTAG('d','h','a','v'))
343  return AVERROR_INVALIDDATA;
344  avio_skip(s->pb, 4);
345 
346  return ret;
347 }
348 
349 static int dhav_read_seek(AVFormatContext *s, int stream_index,
350  int64_t timestamp, int flags)
351 {
352  AVStream *st = s->streams[stream_index];
353  int index = av_index_search_timestamp(st, timestamp, flags);
354  int64_t pts;
355 
356  if (index < 0)
357  return -1;
358  if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)
359  return -1;
360 
361  pts = st->index_entries[index].timestamp;
362 
363  for (int n = 0; n < s->nb_streams; n++) {
364  AVStream *st = s->streams[n];
365  DHAVStream *dst = st->priv_data;
366 
367  dst->pts = pts;
369  }
370 
371  return 0;
372 }
373 
375  .name = "dhav",
376  .long_name = NULL_IF_CONFIG_SMALL("Video DAV"),
377  .priv_data_size = sizeof(DHAVContext),
382  .extensions = "dav",
384 };
#define NULL
Definition: coverity.c:32
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1497
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:4882
int64_t pos
Definition: avformat.h:810
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:153
static int read_chunk(AVFormatContext *s)
Definition: dhav.c:215
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3953
int num
Numerator.
Definition: rational.h:59
int index
stream index in AVFormatContext
Definition: avformat.h:882
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:246
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:1110
GLint GLenum type
Definition: opengl_enc.c:104
void * priv_data
Definition: avformat.h:896
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:331
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:236
static AVPacket pkt
static const uint32_t sample_rates[]
Definition: dhav.c:123
int ctx_flags
Flags signalling stream properties.
Definition: avformat.h:1407
Format I/O context.
Definition: avformat.h:1358
unsigned channel
Definition: dhav.c:31
static const char signature[]
Definition: ipmovie.c:615
void void avpriv_request_sample(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
uint8_t
int width
Video only.
Definition: avcodec.h:4019
#define AVFMTCTX_NOHEADER
signal that no header is present (streams are added dynamically)
Definition: avformat.h:1302
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1495
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4455
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1426
unsigned date
Definition: dhav.c:34
#define AVERROR_EOF
End of file.
Definition: error.h:55
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:310
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:648
static int dhav_read_header(AVFormatContext *s)
Definition: dhav.c:68
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1509
unsigned subtype
Definition: dhav.c:30
int64_t last_timestamp
Definition: dhav.c:48
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:2148
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:770
unsigned type
Definition: dhav.c:29
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:811
int64_t pts
Definition: dhav.c:49
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
int audio_channels
Definition: dhav.c:39
static int dhav_probe(const AVProbeData *p)
Definition: dhav.c:52
preferred ID for decoding MPEG audio layer 1, 2 or 3
Definition: avcodec.h:565
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3949
static int64_t get_pts(AVFormatContext *s, DHAVStream *st)
Definition: dhav.c:87
GLsizei GLsizei * length
Definition: opengl_enc.c:114
int video_codec
Definition: dhav.c:37
AVRational avg_frame_rate
Average framerate.
Definition: avformat.h:954
AVInputFormat ff_dhav_demuxer
Definition: dhav.c:374
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1483
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:639
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1414
unsigned timestamp
Definition: dhav.c:35
static int dhav_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dhav.c:258
#define s(width, name)
Definition: cbs_vp9.c:257
int n
Definition: avisynth_c.h:760
int video_stream_index
Definition: dhav.c:43
int width
Definition: dhav.c:36
#define FF_ARRAY_ELEMS(a)
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
#define AV_LOG_INFO
Standard information.
Definition: log.h:187
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
static int dhav_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: dhav.c:349
unsigned frame_number
Definition: dhav.c:33
int sample_rate
Definition: dhav.c:41
int index
Definition: gxfenc.c:89
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:468
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
misc parsing utilities
static int64_t pts
#define flags(name, subs,...)
Definition: cbs_av1.c:561
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
int ffio_ensure_seekback(AVIOContext *s, int64_t buf_size)
Ensures that the requested seekback buffer size will be available.
Definition: aviobuf.c:1052
int sample_rate
Audio only.
Definition: avcodec.h:4063
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:754
Main libavformat public API header.
int den
Denominator.
Definition: rational.h:60
int audio_stream_index
Definition: dhav.c:44
unsigned frame_subnumber
Definition: dhav.c:32
#define AVFMT_NO_BYTE_SEEK
Format does not allow seeking by bytes.
Definition: avformat.h:475
void * priv_data
Format private data.
Definition: avformat.h:1386
int audio_codec
Definition: dhav.c:40
int height
Definition: dhav.c:36
int channels
Audio only.
Definition: avcodec.h:4059
void INT64 start
Definition: avisynth_c.h:766
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
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:358
int stream_index
Definition: avcodec.h:1479
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
#define MKTAG(a, b, c, d)
Definition: common.h:366
int frame_rate
Definition: dhav.c:38
This structure stores compressed data.
Definition: avcodec.h:1454
static int parse_ext(AVFormatContext *s, int length)
Definition: dhav.c:129
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1470
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248