FFmpeg
lxfdec.c
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1 /*
2  * LXF demuxer
3  * Copyright (c) 2010 Tomas Härdin
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 #include <inttypes.h>
23 
24 #include "libavutil/intreadwrite.h"
25 #include "libavcodec/bytestream.h"
26 #include "avformat.h"
27 #include "demux.h"
28 #include "internal.h"
29 
30 #define LXF_MAX_PACKET_HEADER_SIZE 256
31 #define LXF_HEADER_DATA_SIZE 120
32 #define LXF_IDENT "LEITCH\0"
33 #define LXF_IDENT_LENGTH 8
34 #define LXF_SAMPLERATE 48000
35 
36 static const AVCodecTag lxf_tags[] = {
37  { AV_CODEC_ID_MJPEG, 0 },
39  { AV_CODEC_ID_MPEG2VIDEO, 2 }, //MpMl, 4:2:0
40  { AV_CODEC_ID_MPEG2VIDEO, 3 }, //MpPl, 4:2:2
41  { AV_CODEC_ID_DVVIDEO, 4 }, //DV25
42  { AV_CODEC_ID_DVVIDEO, 5 }, //DVCPRO
43  { AV_CODEC_ID_DVVIDEO, 6 }, //DVCPRO50
44  { AV_CODEC_ID_RAWVIDEO, 7 }, //AV_PIX_FMT_ARGB, where alpha is used for chroma keying
45  { AV_CODEC_ID_RAWVIDEO, 8 }, //16-bit chroma key
46  { AV_CODEC_ID_MPEG2VIDEO, 9 }, //4:2:2 CBP ("Constrained Bytes per Gop")
47  { AV_CODEC_ID_NONE, 0 },
48 };
49 
50 typedef struct LXFDemuxContext {
51  int channels; ///< number of audio channels. zero means no audio
52  int frame_number; ///< current video frame
55 
56 static int lxf_probe(const AVProbeData *p)
57 {
58  if (!memcmp(p->buf, LXF_IDENT, LXF_IDENT_LENGTH))
59  return AVPROBE_SCORE_MAX;
60 
61  return 0;
62 }
63 
64 /**
65  * Verify the checksum of an LXF packet header
66  *
67  * @param[in] header the packet header to check
68  * @return zero if the checksum is OK, non-zero otherwise
69  */
70 static int check_checksum(const uint8_t *header, int size)
71 {
72  int x;
73  uint32_t sum = 0;
74 
75  for (x = 0; x < size; x += 4)
76  sum += AV_RL32(&header[x]);
77 
78  return sum;
79 }
80 
81 /**
82  * Read input until we find the next ident. If found, copy it to the header buffer
83  *
84  * @param[out] header where to copy the ident to
85  * @return 0 if an ident was found, < 0 on I/O error
86  */
87 static int lxf_sync(AVFormatContext *s, uint8_t *header)
88 {
89  uint8_t buf[LXF_IDENT_LENGTH];
90  int ret;
91 
92  if ((ret = avio_read(s->pb, buf, LXF_IDENT_LENGTH)) != LXF_IDENT_LENGTH)
93  return ret < 0 ? ret : AVERROR_EOF;
94 
95  while (memcmp(buf, LXF_IDENT, LXF_IDENT_LENGTH)) {
96  if (avio_feof(s->pb))
97  return AVERROR_EOF;
98 
99  memmove(buf, &buf[1], LXF_IDENT_LENGTH-1);
100  buf[LXF_IDENT_LENGTH-1] = avio_r8(s->pb);
101  }
102 
104 
105  return 0;
106 }
107 
108 /**
109  * Read and checksum the next packet header
110  *
111  * @return the size of the payload following the header or < 0 on failure
112  */
114 {
115  LXFDemuxContext *lxf = s->priv_data;
116  AVIOContext *pb = s->pb;
117  int track_size, samples, ret;
118  uint32_t version, audio_format, header_size, channels, tmp;
119  AVStream *st;
121  const uint8_t *p = header + LXF_IDENT_LENGTH;
122 
123  //find and read the ident
124  if ((ret = lxf_sync(s, header)) < 0)
125  return ret;
126 
127  ret = avio_read(pb, header + LXF_IDENT_LENGTH, 8);
128  if (ret != 8)
129  return ret < 0 ? ret : AVERROR_EOF;
130 
131  version = bytestream_get_le32(&p);
132  header_size = bytestream_get_le32(&p);
133  if (version > 1)
134  avpriv_request_sample(s, "Format version %"PRIu32, version);
135 
136  if (header_size < (version ? 72 : 60) ||
137  header_size > LXF_MAX_PACKET_HEADER_SIZE ||
138  (header_size & 3)) {
139  av_log(s, AV_LOG_ERROR, "Invalid header size 0x%"PRIx32"\n", header_size);
140  return AVERROR_INVALIDDATA;
141  }
142 
143  //read the rest of the packet header
144  if ((ret = avio_read(pb, header + (p - header),
145  header_size - (p - header))) !=
146  header_size - (p - header))
147  return ret < 0 ? ret : AVERROR_EOF;
148 
149  if (check_checksum(header, header_size))
150  av_log(s, AV_LOG_ERROR, "checksum error\n");
151 
152  lxf->packet_type = bytestream_get_le32(&p);
153  p += version ? 20 : 12;
154 
155  lxf->extended_size = 0;
156  switch (lxf->packet_type) {
157  case 0:
158  //video
159  lxf->video_format = bytestream_get_le32(&p);
160  ret = bytestream_get_le32(&p);
161  //skip VBI data and metadata
162  avio_skip(pb, (int64_t)(uint32_t)AV_RL32(p + 4) +
163  (int64_t)(uint32_t)AV_RL32(p + 12));
164  break;
165  case 1:
166  //audio
167  if (s->nb_streams < 2) {
168  av_log(s, AV_LOG_INFO, "got audio packet, but no audio stream present\n");
169  break;
170  }
171 
172  if (version == 0)
173  p += 8;
174  audio_format = bytestream_get_le32(&p);
175  channels = bytestream_get_le32(&p);
176  track_size = bytestream_get_le32(&p);
177 
178  st = s->streams[1];
179 
180  //set codec based on specified audio bitdepth
181  //we only support tightly packed 16-, 20-, 24- and 32-bit PCM at the moment
182  st->codecpar->bits_per_coded_sample = (audio_format >> 6) & 0x3F;
183 
184  if (st->codecpar->bits_per_coded_sample != (audio_format & 0x3F)) {
185  avpriv_report_missing_feature(s, "Not tightly packed PCM");
186  return AVERROR_PATCHWELCOME;
187  }
188 
189  switch (st->codecpar->bits_per_coded_sample) {
190  case 16: st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE_PLANAR; break;
191  case 20: st->codecpar->codec_id = AV_CODEC_ID_PCM_LXF; break;
192  case 24: st->codecpar->codec_id = AV_CODEC_ID_PCM_S24LE_PLANAR; break;
193  case 32: st->codecpar->codec_id = AV_CODEC_ID_PCM_S32LE_PLANAR; break;
194  default:
195  avpriv_report_missing_feature(s, "PCM not 16-, 20-, 24- or 32-bits");
196  return AVERROR_PATCHWELCOME;
197  }
198 
199  samples = track_size * 8LL / st->codecpar->bits_per_coded_sample;
200 
201  //use audio packet size to determine video standard
202  //for NTSC we have one 8008-sample audio frame per five video frames
203  if (samples == LXF_SAMPLERATE * 5005 / 30000) {
204  avpriv_set_pts_info(s->streams[0], 64, 1001, 30000);
205  } else {
206  //assume PAL, but warn if we don't have 1920 samples
207  if (samples != LXF_SAMPLERATE / 25)
209  "video doesn't seem to be PAL or NTSC. guessing PAL\n");
210 
211  avpriv_set_pts_info(s->streams[0], 64, 1, 25);
212  }
213 
214  if (av_popcount(channels) * (uint64_t)track_size > INT_MAX)
215  return AVERROR_INVALIDDATA;
216  //TODO: warning if track mask != (1 << channels) - 1?
217  ret = av_popcount(channels) * track_size;
218 
219  break;
220  default:
221  tmp = bytestream_get_le32(&p);
222  ret = bytestream_get_le32(&p);
223  if (tmp == 1)
224  lxf->extended_size = bytestream_get_le32(&p);
225  break;
226  }
227 
228  return ret;
229 }
230 
232 {
233  LXFDemuxContext *lxf = s->priv_data;
234  AVIOContext *pb = s->pb;
235  uint8_t header_data[LXF_HEADER_DATA_SIZE];
236  int ret;
237  AVStream *st;
238  uint32_t video_params, disk_params;
239  uint16_t record_date, expiration_date;
240 
241  if ((ret = get_packet_header(s)) < 0)
242  return ret;
243 
244  if (ret != LXF_HEADER_DATA_SIZE) {
245  av_log(s, AV_LOG_ERROR, "expected %d B size header, got %d\n",
247  return AVERROR_INVALIDDATA;
248  }
249 
250  if ((ret = avio_read(pb, header_data, LXF_HEADER_DATA_SIZE)) != LXF_HEADER_DATA_SIZE)
251  return ret < 0 ? ret : AVERROR_EOF;
252 
253  if (!(st = avformat_new_stream(s, NULL)))
254  return AVERROR(ENOMEM);
255 
256  st->duration = AV_RL32(&header_data[32]);
257  video_params = AV_RL32(&header_data[40]);
258  record_date = AV_RL16(&header_data[56]);
259  expiration_date = AV_RL16(&header_data[58]);
260  disk_params = AV_RL32(&header_data[116]);
261 
263  st->codecpar->bit_rate = 1000000 * ((video_params >> 14) & 0xFF);
264  st->codecpar->codec_tag = video_params & 0xF;
267 
268  av_log(s, AV_LOG_DEBUG, "record: %x = %i-%02i-%02i\n",
269  record_date, 1900 + (record_date & 0x7F), (record_date >> 7) & 0xF,
270  (record_date >> 11) & 0x1F);
271 
272  av_log(s, AV_LOG_DEBUG, "expire: %x = %i-%02i-%02i\n",
273  expiration_date, 1900 + (expiration_date & 0x7F), (expiration_date >> 7) & 0xF,
274  (expiration_date >> 11) & 0x1F);
275 
276  if ((video_params >> 22) & 1)
277  av_log(s, AV_LOG_WARNING, "VBI data not yet supported\n");
278 
279  if ((lxf->channels = 1 << (disk_params >> 4 & 3) + 1)) {
280  if (!(st = avformat_new_stream(s, NULL)))
281  return AVERROR(ENOMEM);
282 
286 
287  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
288  }
289 
290  avio_skip(s->pb, lxf->extended_size);
291 
292  return 0;
293 }
294 
296 {
297  LXFDemuxContext *lxf = s->priv_data;
298  AVIOContext *pb = s->pb;
299  uint32_t stream;
300  int ret, ret2;
301 
302  if ((ret = get_packet_header(s)) < 0)
303  return ret;
304 
305  stream = lxf->packet_type;
306 
307  if (stream > 1) {
309  "got packet with illegal stream index %"PRIu32"\n", stream);
310  return FFERROR_REDO;
311  }
312 
313  if (stream == 1 && s->nb_streams < 2) {
314  av_log(s, AV_LOG_ERROR, "got audio packet without having an audio stream\n");
315  return AVERROR_INVALIDDATA;
316  }
317 
318  if ((ret2 = av_new_packet(pkt, ret)) < 0)
319  return ret2;
320 
321  if ((ret2 = avio_read(pb, pkt->data, ret)) != ret) {
322  return ret2 < 0 ? ret2 : AVERROR_EOF;
323  }
324 
325  pkt->stream_index = stream;
326 
327  if (!stream) {
328  //picture type (0 = closed I, 1 = open I, 2 = P, 3 = B)
329  if (((lxf->video_format >> 22) & 0x3) < 2)
331 
332  pkt->dts = lxf->frame_number++;
333  }
334 
335  return ret;
336 }
337 
339  .name = "lxf",
340  .long_name = NULL_IF_CONFIG_SMALL("VR native stream (LXF)"),
341  .priv_data_size = sizeof(LXFDemuxContext),
345  .codec_tag = (const AVCodecTag* const []){lxf_tags, 0},
346 };
LXFDemuxContext::extended_size
uint32_t extended_size
Definition: lxfdec.c:53
LXF_IDENT
#define LXF_IDENT
Definition: lxfdec.c:32
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h: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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: options.c:237
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:57
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
AV_CODEC_ID_RAWVIDEO
@ AV_CODEC_ID_RAWVIDEO
Definition: codec_id.h:63
AV_CODEC_ID_PCM_S32LE_PLANAR
@ AV_CODEC_ID_PCM_S32LE_PLANAR
Definition: codec_id.h:346
tmp
static uint8_t tmp[11]
Definition: aes_ctr.c:28
AVPacket::data
uint8_t * data
Definition: packet.h:374
AVCodecParameters::codec_tag
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:65
av_popcount
#define av_popcount
Definition: common.h:149
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:300
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:429
AV_CODEC_ID_PCM_S16LE_PLANAR
@ AV_CODEC_ID_PCM_S16LE_PLANAR
Definition: codec_id.h:335
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:465
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:697
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:407
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:998
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AVInputFormat
Definition: avformat.h:656
AVCodecTag
Definition: internal.h:50
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:256
AV_CODEC_ID_PCM_LXF
@ AV_CODEC_ID_PCM_LXF
Definition: codec_id.h:342
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:661
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:455
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AV_LOG_DEBUG
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:201
channels
channels
Definition: aptx.h:32
AV_RL16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:94
LXFDemuxContext::frame_number
int frame_number
current video frame
Definition: lxfdec.c:52
lxf_read_packet
static int lxf_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: lxfdec.c:295
LXF_MAX_PACKET_HEADER_SIZE
#define LXF_MAX_PACKET_HEADER_SIZE
Definition: lxfdec.c:30
FFStream::need_parsing
enum AVStreamParseType need_parsing
Definition: internal.h:380
AVFormatContext
Format I/O context.
Definition: avformat.h:1213
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1108
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:529
NULL
#define NULL
Definition: coverity.c:32
LXF_SAMPLERATE
#define LXF_SAMPLERATE
Definition: lxfdec.c:34
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:453
check_checksum
static int check_checksum(const uint8_t *header, int size)
Verify the checksum of an LXF packet header.
Definition: lxfdec.c:70
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:212
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:177
AV_CODEC_ID_MPEG1VIDEO
@ AV_CODEC_ID_MPEG1VIDEO
Definition: codec_id.h:51
AV_CODEC_ID_PCM_S24LE_PLANAR
@ AV_CODEC_ID_PCM_S24LE_PLANAR
Definition: codec_id.h:345
LXFDemuxContext
Definition: lxfdec.c:50
lxf_sync
static int lxf_sync(AVFormatContext *s, uint8_t *header)
Read input until we find the next ident.
Definition: lxfdec.c:87
AVIOContext
Bytestream IO Context.
Definition: avio.h:162
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:117
ff_codec_get_id
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag)
Definition: utils.c:144
lxf_tags
static const AVCodecTag lxf_tags[]
Definition: lxfdec.c:36
size
int size
Definition: twinvq_data.h:10344
avpriv_report_missing_feature
void avpriv_report_missing_feature(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
header
static const uint8_t header[24]
Definition: sdr2.c:67
AVPacket::dts
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed.
Definition: packet.h:373
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:632
LXFDemuxContext::channels
int channels
number of audio channels. zero means no audio
Definition: lxfdec.c:51
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:380
version
version
Definition: libkvazaar.c:313
AV_LOG_INFO
#define AV_LOG_INFO
Standard information.
Definition: log.h:191
FFERROR_REDO
#define FFERROR_REDO
Returned by demuxers to indicate that data was consumed but discarded (ignored streams or junk data).
Definition: demux.h:62
AV_CODEC_ID_MJPEG
@ AV_CODEC_ID_MJPEG
Definition: codec_id.h:57
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:48
AV_CODEC_ID_DVVIDEO
@ AV_CODEC_ID_DVVIDEO
Definition: codec_id.h:74
demux.h
ff_lxf_demuxer
const AVInputFormat ff_lxf_demuxer
Definition: lxfdec.c:338
ret
ret
Definition: filter_design.txt:187
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVStream
Stream structure.
Definition: avformat.h:948
AVSTREAM_PARSE_HEADERS
@ AVSTREAM_PARSE_HEADERS
Only parse headers, do not repack.
Definition: avformat.h:799
avformat.h
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
lxf_read_header
static int lxf_read_header(AVFormatContext *s)
Definition: lxfdec.c:231
LXF_IDENT_LENGTH
#define LXF_IDENT_LENGTH
Definition: lxfdec.c:33
LXFDemuxContext::packet_type
uint32_t packet_type
Definition: lxfdec.c:53
LXFDemuxContext::video_format
uint32_t video_format
Definition: lxfdec.c:53
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:641
samples
Filter the word “frame” indicates either a video frame or a group of audio samples
Definition: filter_design.txt:8
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:347
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:103
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:36
lxf_probe
static int lxf_probe(const AVProbeData *p)
Definition: lxfdec.c:56
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:61
AVPacket
This structure stores compressed data.
Definition: packet.h:351
bytestream.h
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:90
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
get_packet_header
static int get_packet_header(AVFormatContext *s)
Read and checksum the next packet header.
Definition: lxfdec.c:113
AV_CODEC_ID_MPEG2VIDEO
@ AV_CODEC_ID_MPEG2VIDEO
preferred ID for MPEG-1/2 video decoding
Definition: codec_id.h:52
LXF_HEADER_DATA_SIZE
#define LXF_HEADER_DATA_SIZE
Definition: lxfdec.c:31
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:375