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 },
37 { AV_CODEC_ID_MPEG1VIDEO, 1 },
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
52 uint32_t video_format, packet_type, extended_size;
53 } LXFDemuxContext;
54
lxf_probe(const AVProbeData * p)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 */
check_checksum(const uint8_t * header,int size)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 */
lxf_sync(AVFormatContext * s,uint8_t * header)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
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 */
get_packet_header(AVFormatContext * s)112 static int get_packet_header(AVFormatContext *s)
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;
119 uint8_t header[LXF_MAX_PACKET_HEADER_SIZE];
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)
207 av_log(s, AV_LOG_WARNING,
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
lxf_read_header(AVFormatContext * s)228 static int lxf_read_header(AVFormatContext *s)
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
259 st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
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);
263 st->need_parsing = AVSTREAM_PARSE_HEADERS;
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
280 st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
281 st->codecpar->sample_rate = LXF_SAMPLERATE;
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
lxf_read_packet(AVFormatContext * s,AVPacket * pkt)292 static int lxf_read_packet(AVFormatContext *s, AVPacket *pkt)
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) {
305 av_log(s, AV_LOG_WARNING,
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 return ret2 < 0 ? ret2 : AVERROR_EOF;
320 }
321
322 pkt->stream_index = stream;
323
324 if (!stream) {
325 //picture type (0 = closed I, 1 = open I, 2 = P, 3 = B)
326 if (((lxf->video_format >> 22) & 0x3) < 2)
327 pkt->flags |= AV_PKT_FLAG_KEY;
328
329 pkt->dts = lxf->frame_number++;
330 }
331
332 return ret;
333 }
334
335 AVInputFormat ff_lxf_demuxer = {
336 .name = "lxf",
337 .long_name = NULL_IF_CONFIG_SMALL("VR native stream (LXF)"),
338 .priv_data_size = sizeof(LXFDemuxContext),
339 .read_probe = lxf_probe,
340 .read_header = lxf_read_header,
341 .read_packet = lxf_read_packet,
342 .codec_tag = (const AVCodecTag* const []){lxf_tags, 0},
343 };
344