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 "internal.h"
28 
29 #define LXF_MAX_PACKET_HEADER_SIZE 256
30 #define LXF_HEADER_DATA_SIZE 120
31 #define LXF_IDENT "LEITCH\0"
32 #define LXF_IDENT_LENGTH 8
33 #define LXF_SAMPLERATE 48000
34 
35 static const AVCodecTag lxf_tags[] = {
36  { AV_CODEC_ID_MJPEG, 0 },
38  { AV_CODEC_ID_MPEG2VIDEO, 2 }, //MpMl, 4:2:0
39  { AV_CODEC_ID_MPEG2VIDEO, 3 }, //MpPl, 4:2:2
40  { AV_CODEC_ID_DVVIDEO, 4 }, //DV25
41  { AV_CODEC_ID_DVVIDEO, 5 }, //DVCPRO
42  { AV_CODEC_ID_DVVIDEO, 6 }, //DVCPRO50
43  { AV_CODEC_ID_RAWVIDEO, 7 }, //AV_PIX_FMT_ARGB, where alpha is used for chroma keying
44  { AV_CODEC_ID_RAWVIDEO, 8 }, //16-bit chroma key
45  { AV_CODEC_ID_MPEG2VIDEO, 9 }, //4:2:2 CBP ("Constrained Bytes per Gop")
46  { AV_CODEC_ID_NONE, 0 },
47 };
48 
49 typedef struct LXFDemuxContext {
50  int channels; ///< number of audio channels. zero means no audio
51  int frame_number; ///< current video frame
54 
55 static int lxf_probe(const AVProbeData *p)
56 {
57  if (!memcmp(p->buf, LXF_IDENT, LXF_IDENT_LENGTH))
58  return AVPROBE_SCORE_MAX;
59 
60  return 0;
61 }
62 
63 /**
64  * Verify the checksum of an LXF packet header
65  *
66  * @param[in] header the packet header to check
67  * @return zero if the checksum is OK, non-zero otherwise
68  */
69 static int check_checksum(const uint8_t *header, int size)
70 {
71  int x;
72  uint32_t sum = 0;
73 
74  for (x = 0; x < size; x += 4)
75  sum += AV_RL32(&header[x]);
76 
77  return sum;
78 }
79 
80 /**
81  * Read input until we find the next ident. If found, copy it to the header buffer
82  *
83  * @param[out] header where to copy the ident to
84  * @return 0 if an ident was found, < 0 on I/O error
85  */
86 static int lxf_sync(AVFormatContext *s, uint8_t *header)
87 {
88  uint8_t buf[LXF_IDENT_LENGTH];
89  int ret;
90 
91  if ((ret = avio_read(s->pb, buf, LXF_IDENT_LENGTH)) != LXF_IDENT_LENGTH)
92  return ret < 0 ? ret : AVERROR_EOF;
93 
94  while (memcmp(buf, LXF_IDENT, LXF_IDENT_LENGTH)) {
95  if (avio_feof(s->pb))
96  return AVERROR_EOF;
97 
98  memmove(buf, &buf[1], LXF_IDENT_LENGTH-1);
99  buf[LXF_IDENT_LENGTH-1] = avio_r8(s->pb);
100  }
101 
103 
104  return 0;
105 }
106 
107 /**
108  * Read and checksum the next packet header
109  *
110  * @return the size of the payload following the header or < 0 on failure
111  */
113 {
114  LXFDemuxContext *lxf = s->priv_data;
115  AVIOContext *pb = s->pb;
116  int track_size, samples, ret;
117  uint32_t version, audio_format, header_size, channels, tmp;
118  AVStream *st;
120  const uint8_t *p = header + LXF_IDENT_LENGTH;
121 
122  //find and read the ident
123  if ((ret = lxf_sync(s, header)) < 0)
124  return ret;
125 
126  ret = avio_read(pb, header + LXF_IDENT_LENGTH, 8);
127  if (ret != 8)
128  return ret < 0 ? ret : AVERROR_EOF;
129 
130  version = bytestream_get_le32(&p);
131  header_size = bytestream_get_le32(&p);
132  if (version > 1)
133  avpriv_request_sample(s, "Format version %"PRIu32, version);
134 
135  if (header_size < (version ? 72 : 60) ||
136  header_size > LXF_MAX_PACKET_HEADER_SIZE ||
137  (header_size & 3)) {
138  av_log(s, AV_LOG_ERROR, "Invalid header size 0x%"PRIx32"\n", header_size);
139  return AVERROR_INVALIDDATA;
140  }
141 
142  //read the rest of the packet header
143  if ((ret = avio_read(pb, header + (p - header),
144  header_size - (p - header))) !=
145  header_size - (p - header))
146  return ret < 0 ? ret : AVERROR_EOF;
147 
148  if (check_checksum(header, header_size))
149  av_log(s, AV_LOG_ERROR, "checksum error\n");
150 
151  lxf->packet_type = bytestream_get_le32(&p);
152  p += version ? 20 : 12;
153 
154  lxf->extended_size = 0;
155  switch (lxf->packet_type) {
156  case 0:
157  //video
158  lxf->video_format = bytestream_get_le32(&p);
159  ret = bytestream_get_le32(&p);
160  //skip VBI data and metadata
161  avio_skip(pb, (int64_t)(uint32_t)AV_RL32(p + 4) +
162  (int64_t)(uint32_t)AV_RL32(p + 12));
163  break;
164  case 1:
165  //audio
166  if (s->nb_streams < 2) {
167  av_log(s, AV_LOG_INFO, "got audio packet, but no audio stream present\n");
168  break;
169  }
170 
171  if (version == 0)
172  p += 8;
173  audio_format = bytestream_get_le32(&p);
174  channels = bytestream_get_le32(&p);
175  track_size = bytestream_get_le32(&p);
176 
177  st = s->streams[1];
178 
179  //set codec based on specified audio bitdepth
180  //we only support tightly packed 16-, 20-, 24- and 32-bit PCM at the moment
181  st->codecpar->bits_per_coded_sample = (audio_format >> 6) & 0x3F;
182 
183  if (st->codecpar->bits_per_coded_sample != (audio_format & 0x3F)) {
184  avpriv_report_missing_feature(s, "Not tightly packed PCM");
185  return AVERROR_PATCHWELCOME;
186  }
187 
188  switch (st->codecpar->bits_per_coded_sample) {
189  case 16: st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE_PLANAR; break;
190  case 20: st->codecpar->codec_id = AV_CODEC_ID_PCM_LXF; break;
191  case 24: st->codecpar->codec_id = AV_CODEC_ID_PCM_S24LE_PLANAR; break;
192  case 32: st->codecpar->codec_id = AV_CODEC_ID_PCM_S32LE_PLANAR; break;
193  default:
194  avpriv_report_missing_feature(s, "PCM not 16-, 20-, 24- or 32-bits");
195  return AVERROR_PATCHWELCOME;
196  }
197 
198  samples = track_size * 8LL / st->codecpar->bits_per_coded_sample;
199 
200  //use audio packet size to determine video standard
201  //for NTSC we have one 8008-sample audio frame per five video frames
202  if (samples == LXF_SAMPLERATE * 5005 / 30000) {
203  avpriv_set_pts_info(s->streams[0], 64, 1001, 30000);
204  } else {
205  //assume PAL, but warn if we don't have 1920 samples
206  if (samples != LXF_SAMPLERATE / 25)
208  "video doesn't seem to be PAL or NTSC. guessing PAL\n");
209 
210  avpriv_set_pts_info(s->streams[0], 64, 1, 25);
211  }
212 
213  if (av_popcount(channels) * (uint64_t)track_size > INT_MAX)
214  return AVERROR_INVALIDDATA;
215  //TODO: warning if track mask != (1 << channels) - 1?
216  ret = av_popcount(channels) * track_size;
217 
218  break;
219  default:
220  tmp = bytestream_get_le32(&p);
221  ret = bytestream_get_le32(&p);
222  if (tmp == 1)
223  lxf->extended_size = bytestream_get_le32(&p);
224  break;
225  }
226 
227  return ret;
228 }
229 
231 {
232  LXFDemuxContext *lxf = s->priv_data;
233  AVIOContext *pb = s->pb;
234  uint8_t header_data[LXF_HEADER_DATA_SIZE];
235  int ret;
236  AVStream *st;
237  uint32_t video_params, disk_params;
238  uint16_t record_date, expiration_date;
239 
240  if ((ret = get_packet_header(s)) < 0)
241  return ret;
242 
243  if (ret != LXF_HEADER_DATA_SIZE) {
244  av_log(s, AV_LOG_ERROR, "expected %d B size header, got %d\n",
246  return AVERROR_INVALIDDATA;
247  }
248 
249  if ((ret = avio_read(pb, header_data, LXF_HEADER_DATA_SIZE)) != LXF_HEADER_DATA_SIZE)
250  return ret < 0 ? ret : AVERROR_EOF;
251 
252  if (!(st = avformat_new_stream(s, NULL)))
253  return AVERROR(ENOMEM);
254 
255  st->duration = AV_RL32(&header_data[32]);
256  video_params = AV_RL32(&header_data[40]);
257  record_date = AV_RL16(&header_data[56]);
258  expiration_date = AV_RL16(&header_data[58]);
259  disk_params = AV_RL32(&header_data[116]);
260 
262  st->codecpar->bit_rate = 1000000 * ((video_params >> 14) & 0xFF);
263  st->codecpar->codec_tag = video_params & 0xF;
266 
267  av_log(s, AV_LOG_DEBUG, "record: %x = %i-%02i-%02i\n",
268  record_date, 1900 + (record_date & 0x7F), (record_date >> 7) & 0xF,
269  (record_date >> 11) & 0x1F);
270 
271  av_log(s, AV_LOG_DEBUG, "expire: %x = %i-%02i-%02i\n",
272  expiration_date, 1900 + (expiration_date & 0x7F), (expiration_date >> 7) & 0xF,
273  (expiration_date >> 11) & 0x1F);
274 
275  if ((video_params >> 22) & 1)
276  av_log(s, AV_LOG_WARNING, "VBI data not yet supported\n");
277 
278  if ((lxf->channels = 1 << (disk_params >> 4 & 3) + 1)) {
279  if (!(st = avformat_new_stream(s, NULL)))
280  return AVERROR(ENOMEM);
281 
284  st->codecpar->channels = lxf->channels;
285 
286  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
287  }
288 
289  avio_skip(s->pb, lxf->extended_size);
290 
291  return 0;
292 }
293 
295 {
296  LXFDemuxContext *lxf = s->priv_data;
297  AVIOContext *pb = s->pb;
298  uint32_t stream;
299  int ret, ret2;
300 
301  if ((ret = get_packet_header(s)) < 0)
302  return ret;
303 
304  stream = lxf->packet_type;
305 
306  if (stream > 1) {
308  "got packet with illegal stream index %"PRIu32"\n", stream);
309  return FFERROR_REDO;
310  }
311 
312  if (stream == 1 && s->nb_streams < 2) {
313  av_log(s, AV_LOG_ERROR, "got audio packet without having an audio stream\n");
314  return AVERROR_INVALIDDATA;
315  }
316 
317  if ((ret2 = av_new_packet(pkt, ret)) < 0)
318  return ret2;
319 
320  if ((ret2 = avio_read(pb, pkt->data, ret)) != ret) {
321  return ret2 < 0 ? ret2 : AVERROR_EOF;
322  }
323 
324  pkt->stream_index = stream;
325 
326  if (!stream) {
327  //picture type (0 = closed I, 1 = open I, 2 = P, 3 = B)
328  if (((lxf->video_format >> 22) & 0x3) < 2)
330 
331  pkt->dts = lxf->frame_number++;
332  }
333 
334  return ret;
335 }
336 
338  .name = "lxf",
339  .long_name = NULL_IF_CONFIG_SMALL("VR native stream (LXF)"),
340  .priv_data_size = sizeof(LXFDemuxContext),
344  .codec_tag = (const AVCodecTag* const []){lxf_tags, 0},
345 };
LXFDemuxContext::extended_size
uint32_t extended_size
Definition: lxfdec.c:52
LXF_IDENT
#define LXF_IDENT
Definition: lxfdec.c:31
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: utils.c:724
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
FFERROR_REDO
#define FFERROR_REDO
Returned by demuxers to indicate that data was consumed but discarded (ignored streams or junk data).
Definition: internal.h:881
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:343
tmp
static uint8_t tmp[11]
Definition: aes_ctr.c:26
AVPacket::data
uint8_t * data
Definition: packet.h:373
AVCodecParameters::codec_tag
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:64
av_popcount
#define av_popcount
Definition: common.h:150
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:425
AV_CODEC_ID_PCM_S16LE_PLANAR
@ AV_CODEC_ID_PCM_S16LE_PLANAR
Definition: codec_id.h:332
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
AVCodecParameters::channels
int channels
Audio only.
Definition: codec_par.h:166
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:429
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:900
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:638
AVCodecTag
Definition: internal.h:50
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:257
AV_CODEC_ID_PCM_LXF
@ AV_CODEC_ID_PCM_LXF
Definition: codec_id.h:339
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:99
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:643
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
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:33
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:51
lxf_read_packet
static int lxf_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: lxfdec.c:294
LXF_MAX_PACKET_HEADER_SIZE
#define LXF_MAX_PACKET_HEADER_SIZE
Definition: lxfdec.c:29
FFStream::need_parsing
enum AVStreamParseType need_parsing
Definition: internal.h:402
AVFormatContext
Format I/O context.
Definition: avformat.h:1109
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1004
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:527
NULL
#define NULL
Definition: coverity.c:32
LXF_SAMPLERATE
#define LXF_SAMPLERATE
Definition: lxfdec.c:33
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:446
check_checksum
static int check_checksum(const uint8_t *header, int size)
Verify the checksum of an LXF packet header.
Definition: lxfdec.c:69
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:170
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:342
LXFDemuxContext
Definition: lxfdec.c:49
lxf_sync
static int lxf_sync(AVFormatContext *s, uint8_t *header)
Read input until we find the next ident.
Definition: lxfdec.c:86
AVIOContext
Bytestream IO Context.
Definition: avio.h:161
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:357
lxf_tags
static const AVCodecTag lxf_tags[]
Definition: lxfdec.c:35
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:372
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:616
LXFDemuxContext::channels
int channels
number of audio channels. zero means no audio
Definition: lxfdec.c:50
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:379
version
version
Definition: libkvazaar.c:307
AV_LOG_INFO
#define AV_LOG_INFO
Standard information.
Definition: log.h:191
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
ff_lxf_demuxer
const AVInputFormat ff_lxf_demuxer
Definition: lxfdec.c:337
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:857
AVSTREAM_PARSE_HEADERS
@ AVSTREAM_PARSE_HEADERS
Only parse headers, do not repack.
Definition: avformat.h:781
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:230
LXF_IDENT_LENGTH
#define LXF_IDENT_LENGTH
Definition: lxfdec.c:32
LXFDemuxContext::packet_type
uint32_t packet_type
Definition: lxfdec.c:52
LXFDemuxContext::video_format
uint32_t video_format
Definition: lxfdec.c:52
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:625
samples
Filter the word “frame” indicates either a video frame or a group of audio samples
Definition: filter_design.txt:8
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: utils.c:1146
AVPacket::stream_index
int stream_index
Definition: packet.h:375
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:333
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:102
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:37
lxf_probe
static int lxf_probe(const AVProbeData *p)
Definition: lxfdec.c:55
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
AVPacket
This structure stores compressed data.
Definition: packet.h:350
bytestream.h
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:89
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
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:112
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:30
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:360