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  */
87 {
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 
102  memcpy(header, LXF_IDENT, LXF_IDENT_LENGTH);
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 * 8 / 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  //TODO: warning if track mask != (1 << channels) - 1?
214  ret = av_popcount(channels) * track_size;
215 
216  break;
217  default:
218  tmp = bytestream_get_le32(&p);
219  ret = bytestream_get_le32(&p);
220  if (tmp == 1)
221  lxf->extended_size = bytestream_get_le32(&p);
222  break;
223  }
224 
225  return ret;
226 }
227 
229 {
230  LXFDemuxContext *lxf = s->priv_data;
231  AVIOContext *pb = s->pb;
232  uint8_t header_data[LXF_HEADER_DATA_SIZE];
233  int ret;
234  AVStream *st;
235  uint32_t video_params, disk_params;
236  uint16_t record_date, expiration_date;
237 
238  if ((ret = get_packet_header(s)) < 0)
239  return ret;
240 
241  if (ret != LXF_HEADER_DATA_SIZE) {
242  av_log(s, AV_LOG_ERROR, "expected %d B size header, got %d\n",
243  LXF_HEADER_DATA_SIZE, ret);
244  return AVERROR_INVALIDDATA;
245  }
246 
247  if ((ret = avio_read(pb, header_data, LXF_HEADER_DATA_SIZE)) != LXF_HEADER_DATA_SIZE)
248  return ret < 0 ? ret : AVERROR_EOF;
249 
250  if (!(st = avformat_new_stream(s, NULL)))
251  return AVERROR(ENOMEM);
252 
253  st->duration = AV_RL32(&header_data[32]);
254  video_params = AV_RL32(&header_data[40]);
255  record_date = AV_RL16(&header_data[56]);
256  expiration_date = AV_RL16(&header_data[58]);
257  disk_params = AV_RL32(&header_data[116]);
258 
260  st->codecpar->bit_rate = 1000000 * ((video_params >> 14) & 0xFF);
261  st->codecpar->codec_tag = video_params & 0xF;
262  st->codecpar->codec_id = ff_codec_get_id(lxf_tags, st->codecpar->codec_tag);
264 
265  av_log(s, AV_LOG_DEBUG, "record: %x = %i-%02i-%02i\n",
266  record_date, 1900 + (record_date & 0x7F), (record_date >> 7) & 0xF,
267  (record_date >> 11) & 0x1F);
268 
269  av_log(s, AV_LOG_DEBUG, "expire: %x = %i-%02i-%02i\n",
270  expiration_date, 1900 + (expiration_date & 0x7F), (expiration_date >> 7) & 0xF,
271  (expiration_date >> 11) & 0x1F);
272 
273  if ((video_params >> 22) & 1)
274  av_log(s, AV_LOG_WARNING, "VBI data not yet supported\n");
275 
276  if ((lxf->channels = 1 << (disk_params >> 4 & 3) + 1)) {
277  if (!(st = avformat_new_stream(s, NULL)))
278  return AVERROR(ENOMEM);
279 
282  st->codecpar->channels = lxf->channels;
283 
284  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
285  }
286 
287  avio_skip(s->pb, lxf->extended_size);
288 
289  return 0;
290 }
291 
293 {
294  LXFDemuxContext *lxf = s->priv_data;
295  AVIOContext *pb = s->pb;
296  uint32_t stream;
297  int ret, ret2;
298 
299  if ((ret = get_packet_header(s)) < 0)
300  return ret;
301 
302  stream = lxf->packet_type;
303 
304  if (stream > 1) {
306  "got packet with illegal stream index %"PRIu32"\n", stream);
307  return FFERROR_REDO;
308  }
309 
310  if (stream == 1 && s->nb_streams < 2) {
311  av_log(s, AV_LOG_ERROR, "got audio packet without having an audio stream\n");
312  return AVERROR_INVALIDDATA;
313  }
314 
315  if ((ret2 = av_new_packet(pkt, ret)) < 0)
316  return ret2;
317 
318  if ((ret2 = avio_read(pb, pkt->data, ret)) != ret) {
319  av_packet_unref(pkt);
320  return ret2 < 0 ? ret2 : AVERROR_EOF;
321  }
322 
323  pkt->stream_index = stream;
324 
325  if (!stream) {
326  //picture type (0 = closed I, 1 = open I, 2 = P, 3 = B)
327  if (((lxf->video_format >> 22) & 0x3) < 2)
328  pkt->flags |= AV_PKT_FLAG_KEY;
329 
330  pkt->dts = lxf->frame_number++;
331  }
332 
333  return ret;
334 }
335 
337  .name = "lxf",
338  .long_name = NULL_IF_CONFIG_SMALL("VR native stream (LXF)"),
339  .priv_data_size = sizeof(LXFDemuxContext),
343  .codec_tag = (const AVCodecTag* const []){lxf_tags, 0},
344 };
#define NULL
Definition: coverity.c:32
Bytestream IO Context.
Definition: avio.h:161
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int frame_number
current video frame
Definition: lxfdec.c:51
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag)
Definition: utils.c:3158
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
static int lxf_sync(AVFormatContext *s, uint8_t *header)
Read input until we find the next ident.
Definition: lxfdec.c:86
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:4929
#define avpriv_request_sample(...)
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3968
static int check_checksum(const uint8_t *header, int size)
Verify the checksum of an LXF packet header.
Definition: lxfdec.c:69
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:334
int version
Definition: avisynth_c.h:858
static AVPacket pkt
AVInputFormat ff_lxf_demuxer
Definition: lxfdec.c:336
int channels
number of audio channels. zero means no audio
Definition: lxfdec.c:50
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:87
Format I/O context.
Definition: avformat.h:1358
uint8_t
enum AVStreamParseType need_parsing
Definition: avformat.h:1099
static int lxf_read_header(AVFormatContext *s)
Definition: lxfdec.c:228
#define LXF_IDENT
Definition: lxfdec.c:31
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4502
#define FFERROR_REDO
Returned by demuxers to indicate that data was consumed but discarded (ignored streams or junk data)...
Definition: internal.h:655
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1426
uint8_t * data
Definition: avcodec.h:1480
#define AVERROR_EOF
End of file.
Definition: error.h:55
ptrdiff_t size
Definition: opengl_enc.c:100
static const uint8_t header[24]
Definition: sdr2.c:67
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:650
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: avcodec.h:3997
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1512
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:86
uint32_t packet_type
Definition: lxfdec.c:52
#define LXF_IDENT_LENGTH
Definition: lxfdec.c:32
uint32_t video_format
Definition: lxfdec.c:52
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3964
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1486
Only parse headers, do not repack.
Definition: avformat.h:801
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:641
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
#define s(width, name)
Definition: cbs_vp9.c:257
preferred ID for MPEG-1/2 video decoding
Definition: avcodec.h:220
#define LXF_MAX_PACKET_HEADER_SIZE
Definition: lxfdec.c:29
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:530
Stream structure.
Definition: avformat.h:881
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
#define LXF_HEADER_DATA_SIZE
Definition: lxfdec.c:30
static int lxf_probe(const AVProbeData *p)
Definition: lxfdec.c:55
#define AV_LOG_INFO
Standard information.
Definition: log.h:187
uint32_t extended_size
Definition: lxfdec.c:52
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:599
static int lxf_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: lxfdec.c:292
void * buf
Definition: avisynth_c.h:766
static int get_packet_header(AVFormatContext *s)
Read and checksum the next packet header.
Definition: lxfdec.c:112
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
static const AVCodecTag lxf_tags[]
Definition: lxfdec.c:35
void avpriv_report_missing_feature(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:930
int sample_rate
Audio only.
Definition: avcodec.h:4078
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
Main libavformat public API header.
void * priv_data
Format private data.
Definition: avformat.h:1386
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: avcodec.h:4010
int channels
Audio only.
Definition: avcodec.h:4074
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
Definition: avcodec.h:1479
Filter the word “frame” indicates either a video frame or a group of audio samples
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:361
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: avcodec.h:3972
int stream_index
Definition: avcodec.h:1482
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
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1457
#define LXF_SAMPLERATE
Definition: lxfdec.c:33
static uint8_t tmp[11]
Definition: aes_ctr.c:26