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1 cc0bc648 Reimar Döffinger
/*
2
 * GXF demuxer.
3
 * Copyright (c) 2006 Reimar Doeffinger.
4
 *
5 b78e7197 Diego Biurrun
 * This file is part of FFmpeg.
6
 *
7
 * FFmpeg is free software; you can redistribute it and/or
8 cc0bc648 Reimar Döffinger
 * modify it under the terms of the GNU Lesser General Public
9
 * License as published by the Free Software Foundation; either
10 b78e7197 Diego Biurrun
 * version 2.1 of the License, or (at your option) any later version.
11 cc0bc648 Reimar Döffinger
 *
12 b78e7197 Diego Biurrun
 * FFmpeg is distributed in the hope that it will be useful,
13 cc0bc648 Reimar Döffinger
 * 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 b78e7197 Diego Biurrun
 * License along with FFmpeg; if not, write to the Free Software
19 cc0bc648 Reimar Döffinger
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20
 */
21
#include "avformat.h"
22 907a0510 Reimar Döffinger
#include "common.h"
23 cc0bc648 Reimar Döffinger
24
typedef enum {
25
    PKT_MAP = 0xbc,
26
    PKT_MEDIA = 0xbf,
27
    PKT_EOS = 0xfb,
28
    PKT_FLT = 0xfc,
29
    PKT_UMF = 0xfd
30
} pkt_type_t;
31
32 907a0510 Reimar Döffinger
typedef enum {
33
    MAT_NAME = 0x40,
34
    MAT_FIRST_FIELD = 0x41,
35
    MAT_LAST_FIELD = 0x42,
36
    MAT_MARK_IN = 0x43,
37
    MAT_MARK_OUT = 0x44,
38
    MAT_SIZE = 0x45
39
} mat_tag_t;
40
41
typedef enum {
42
    TRACK_NAME = 0x4c,
43
    TRACK_AUX = 0x4d,
44
    TRACK_VER = 0x4e,
45
    TRACK_MPG_AUX = 0x4f,
46
    TRACK_FPS = 0x50,
47
    TRACK_LINES = 0x51,
48
    TRACK_FPF = 0x52
49
} track_tag_t;
50
51
typedef struct {
52
    int64_t first_field;
53
    int64_t last_field;
54
    AVRational frames_per_second;
55
    int32_t fields_per_frame;
56
} st_info_t;
57
58 cc0bc648 Reimar Döffinger
/**
59
 * \brief parses a packet header, extracting type and length
60
 * \param pb ByteIOContext to read header from
61
 * \param type detected packet type is stored here
62
 * \param length detected packet length, excluding header is stored here
63
 * \return 0 if header not found or contains invalid data, 1 otherwise
64
 */
65
static int parse_packet_header(ByteIOContext *pb, pkt_type_t *type, int *length) {
66
    if (get_be32(pb))
67
        return 0;
68
    if (get_byte(pb) != 1)
69
        return 0;
70
    *type = get_byte(pb);
71
    *length = get_be32(pb);
72
    if ((*length >> 24) || *length < 16)
73
        return 0;
74
    *length -= 16;
75
    if (get_be32(pb))
76
        return 0;
77
    if (get_byte(pb) != 0xe1)
78
        return 0;
79
    if (get_byte(pb) != 0xe2)
80
        return 0;
81
    return 1;
82
}
83
84
/**
85
 * \brief check if file starts with a PKT_MAP header
86
 */
87
static int gxf_probe(AVProbeData *p) {
88
    static const uint8_t startcode[] = {0, 0, 0, 0, 1, 0xbc}; // start with map packet
89
    static const uint8_t endcode[] = {0, 0, 0, 0, 0xe1, 0xe2};
90
    if (p->buf_size < 16)
91
        return 0;
92
    if (!memcmp(p->buf, startcode, sizeof(startcode)) &&
93
        !memcmp(&p->buf[16 - sizeof(endcode)], endcode, sizeof(endcode)))
94
        return AVPROBE_SCORE_MAX;
95
    return 0;
96
}
97
98
/**
99
 * \brief gets the stream index for the track with the specified id, creates new
100
 *        stream if not found
101
 * \param stream id of stream to find / add
102
 * \param format stream format identifier
103
 */
104
static int get_sindex(AVFormatContext *s, int id, int format) {
105
    int i;
106
    AVStream *st = NULL;
107
    for (i = 0; i < s->nb_streams; i++) {
108
        if (s->streams[i]->id == id)
109
            return i;
110
    }
111
    st = av_new_stream(s, id);
112
    switch (format) {
113
        case 3:
114
        case 4:
115
            st->codec->codec_type = CODEC_TYPE_VIDEO;
116
            st->codec->codec_id = CODEC_ID_MJPEG;
117
            break;
118
        case 13:
119
        case 15:
120
            st->codec->codec_type = CODEC_TYPE_VIDEO;
121
            st->codec->codec_id = CODEC_ID_DVVIDEO;
122
            break;
123
        case 14:
124
        case 16:
125
            st->codec->codec_type = CODEC_TYPE_VIDEO;
126
            st->codec->codec_id = CODEC_ID_DVVIDEO;
127
            break;
128
        case 11:
129
        case 12:
130
        case 20:
131
            st->codec->codec_type = CODEC_TYPE_VIDEO;
132
            st->codec->codec_id = CODEC_ID_MPEG2VIDEO;
133
            break;
134
        case 22:
135
        case 23:
136
            st->codec->codec_type = CODEC_TYPE_VIDEO;
137
            st->codec->codec_id = CODEC_ID_MPEG1VIDEO;
138
            break;
139
        case 9:
140
            st->codec->codec_type = CODEC_TYPE_AUDIO;
141
            st->codec->codec_id = CODEC_ID_PCM_S24LE;
142
            st->codec->channels = 1;
143
            st->codec->sample_rate = 48000;
144
            st->codec->bit_rate = 3 * 1 * 48000 * 8;
145
            st->codec->block_align = 3 * 1;
146
            st->codec->bits_per_sample = 24;
147
            break;
148
        case 10:
149
            st->codec->codec_type = CODEC_TYPE_AUDIO;
150
            st->codec->codec_id = CODEC_ID_PCM_S16LE;
151
            st->codec->channels = 1;
152
            st->codec->sample_rate = 48000;
153
            st->codec->bit_rate = 2 * 1 * 48000 * 8;
154
            st->codec->block_align = 2 * 1;
155
            st->codec->bits_per_sample = 16;
156
            break;
157
        case 17:
158
            st->codec->codec_type = CODEC_TYPE_AUDIO;
159
            st->codec->codec_id = CODEC_ID_AC3;
160
            st->codec->channels = 2;
161
            st->codec->sample_rate = 48000;
162
            break;
163
        default:
164
            st->codec->codec_type = CODEC_TYPE_UNKNOWN;
165
            st->codec->codec_id = CODEC_ID_NONE;
166
            break;
167
    }
168
    return s->nb_streams - 1;
169
}
170
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/**
172
 * \brief filters out interesting tags from material information.
173
 * \param len lenght of tag section, will be adjusted to contain remaining bytes
174
 * \param si struct to store collected information into
175
 */
176
static void gxf_material_tags(ByteIOContext *pb, int *len, st_info_t *si) {
177
    si->first_field = AV_NOPTS_VALUE;
178
    si->last_field = AV_NOPTS_VALUE;
179
    while (*len >= 2) {
180
        mat_tag_t tag = get_byte(pb);
181
        int tlen = get_byte(pb);
182
        *len -= 2;
183
        if (tlen > *len)
184
            return;
185
        *len -= tlen;
186
        if (tlen == 4) {
187
            uint32_t value = get_be32(pb);
188
            if (tag == MAT_FIRST_FIELD)
189
                si->first_field = value;
190
            else if (tag == MAT_LAST_FIELD)
191
                si->last_field = value;
192
        } else
193
            url_fskip(pb, tlen);
194
    }
195
}
196
197
/**
198
 * \brief convert fps tag value to AVRational fps
199
 * \param fps fps value from tag
200
 * \return fps as AVRational, or 0 / 0 if unknown
201
 */
202
static AVRational fps_tag2avr(int32_t fps) {
203
    extern const AVRational ff_frame_rate_tab[];
204
    if (fps < 1 || fps > 9) fps = 9;
205
    return ff_frame_rate_tab[9 - fps]; // values have opposite order
206
}
207
208
/**
209
 * \brief convert UMF attributes flags to AVRational fps
210
 * \param fps fps value from flags
211
 * \return fps as AVRational, or 0 / 0 if unknown
212
 */
213
static AVRational fps_umf2avr(uint32_t flags) {
214
    static const AVRational map[] = {{50, 1}, {60000, 1001}, {24, 1},
215
        {25, 1}, {30000, 1001}};
216
    int idx =  av_log2((flags & 0x7c0) >> 6);
217
    return map[idx];
218
}
219
220
/**
221
 * \brief filters out interesting tags from track information.
222
 * \param len length of tag section, will be adjusted to contain remaining bytes
223
 * \param si struct to store collected information into
224
 */
225
static void gxf_track_tags(ByteIOContext *pb, int *len, st_info_t *si) {
226
    si->frames_per_second = (AVRational){0, 0};
227
    si->fields_per_frame = 0;
228
    while (*len >= 2) {
229
        track_tag_t tag = get_byte(pb);
230
        int tlen = get_byte(pb);
231
        *len -= 2;
232
        if (tlen > *len)
233
            return;
234
        *len -= tlen;
235
        if (tlen == 4) {
236
            uint32_t value = get_be32(pb);
237
            if (tag == TRACK_FPS)
238
                si->frames_per_second = fps_tag2avr(value);
239
            else if (tag == TRACK_FPF && (value == 1 || value == 2))
240
                si->fields_per_frame = value;
241
        } else
242
            url_fskip(pb, tlen);
243
    }
244
}
245
246
/**
247
 * \brief read index from FLT packet into stream 0 av_index
248
 */
249
static void gxf_read_index(AVFormatContext *s, int pkt_len) {
250
    ByteIOContext *pb = &s->pb;
251
    AVStream *st = s->streams[0];
252
    uint32_t fields_per_map = get_le32(pb);
253
    uint32_t map_cnt = get_le32(pb);
254
    int i;
255
    pkt_len -= 8;
256
    if (map_cnt > 1000) {
257
        av_log(s, AV_LOG_ERROR, "GXF: too many index entries %u (%x)\n", map_cnt, map_cnt);
258
        map_cnt = 1000;
259
    }
260
    if (pkt_len < 4 * map_cnt) {
261
        av_log(s, AV_LOG_ERROR, "GXF: invalid index length\n");
262
        url_fskip(pb, pkt_len);
263
        return;
264
    }
265
    pkt_len -= 4 * map_cnt;
266
    av_add_index_entry(st, 0, 0, 0, 0, 0);
267
    for (i = 0; i < map_cnt; i++)
268
        av_add_index_entry(st, (uint64_t)get_le32(pb) * 1024,
269
                           i * (uint64_t)fields_per_map + 1, 0, 0, 0);
270
    url_fskip(pb, pkt_len);
271
}
272
273 cc0bc648 Reimar Döffinger
static int gxf_header(AVFormatContext *s, AVFormatParameters *ap) {
274
    ByteIOContext *pb = &s->pb;
275
    pkt_type_t pkt_type;
276
    int map_len;
277
    int len;
278 907a0510 Reimar Döffinger
    AVRational main_timebase = {0, 0};
279
    st_info_t si;
280
    int i;
281 cc0bc648 Reimar Döffinger
    if (!parse_packet_header(pb, &pkt_type, &map_len) || pkt_type != PKT_MAP) {
282
        av_log(s, AV_LOG_ERROR, "GXF: map packet not found\n");
283
        return 0;
284
    }
285
    map_len -= 2;
286
    if (get_byte(pb) != 0x0e0 || get_byte(pb) != 0xff) {
287
        av_log(s, AV_LOG_ERROR, "GXF: unknown version or invalid map preamble\n");
288
        return 0;
289
    }
290
    map_len -= 2;
291
    len = get_be16(pb); // length of material data section
292
    if (len > map_len) {
293
        av_log(s, AV_LOG_ERROR, "GXF: material data longer than map data\n");
294
        return 0;
295
    }
296
    map_len -= len;
297 907a0510 Reimar Döffinger
    gxf_material_tags(pb, &len, &si);
298 cc0bc648 Reimar Döffinger
    url_fskip(pb, len);
299
    map_len -= 2;
300
    len = get_be16(pb); // length of track description
301
    if (len > map_len) {
302
        av_log(s, AV_LOG_ERROR, "GXF: track description longer than map data\n");
303
        return 0;
304
    }
305
    map_len -= len;
306
    while (len > 0) {
307
        int track_type, track_id, track_len;
308 907a0510 Reimar Döffinger
        AVStream *st;
309
        int idx;
310 cc0bc648 Reimar Döffinger
        len -= 4;
311
        track_type = get_byte(pb);
312
        track_id = get_byte(pb);
313
        track_len = get_be16(pb);
314
        len -= track_len;
315 907a0510 Reimar Döffinger
        gxf_track_tags(pb, &track_len, &si);
316 cc0bc648 Reimar Döffinger
        url_fskip(pb, track_len);
317
        if (!(track_type & 0x80)) {
318
           av_log(s, AV_LOG_ERROR, "GXF: invalid track type %x\n", track_type);
319
           continue;
320
        }
321
        track_type &= 0x7f;
322
        if ((track_id & 0xc0) != 0xc0) {
323
           av_log(s, AV_LOG_ERROR, "GXF: invalid track id %x\n", track_id);
324
           continue;
325
        }
326
        track_id &= 0x3f;
327 907a0510 Reimar Döffinger
        idx = get_sindex(s, track_id, track_type);
328
        if (idx < 0) continue;
329
        st = s->streams[idx];
330
        if (!main_timebase.num || !main_timebase.den) {
331
            main_timebase.num = si.frames_per_second.den;
332
            main_timebase.den = si.frames_per_second.num * si.fields_per_frame;
333
        }
334
        st->start_time = si.first_field;
335
        if (si.first_field != AV_NOPTS_VALUE && si.last_field != AV_NOPTS_VALUE)
336
            st->duration = si.last_field - si.first_field;
337 cc0bc648 Reimar Döffinger
    }
338
    if (len < 0)
339
        av_log(s, AV_LOG_ERROR, "GXF: invalid track description length specified\n");
340
    if (map_len)
341
        url_fskip(pb, map_len);
342 907a0510 Reimar Döffinger
    if (!parse_packet_header(pb, &pkt_type, &len)) {
343
        av_log(s, AV_LOG_ERROR, "GXF: sync lost in header\n");
344
        return -1;
345
    }
346
    if (pkt_type == PKT_FLT) {
347
        gxf_read_index(s, len);
348
        if (!parse_packet_header(pb, &pkt_type, &len)) {
349
            av_log(s, AV_LOG_ERROR, "GXF: sync lost in header\n");
350
            return -1;
351
        }
352
    }
353
    if (pkt_type == PKT_UMF) {
354
        if (len >= 9) {
355
            AVRational fps;
356
            len -= 9;
357
            url_fskip(pb, 5);
358
            fps = fps_umf2avr(get_le32(pb));
359
            if (!main_timebase.num || !main_timebase.den) {
360
                // this may not always be correct, but simply the best we can get
361
                main_timebase.num = fps.den;
362
                main_timebase.den = fps.num;
363
            }
364
        } else
365
            av_log(s, AV_LOG_INFO, "GXF: UMF packet too short\n");
366
    } else
367
        av_log(s, AV_LOG_INFO, "GXF: UMF packet missing\n");
368
    url_fskip(pb, len);
369
    for (i = 0; i < s->nb_streams; i++) {
370
        AVStream *st = s->streams[i];
371
        if (main_timebase.num && main_timebase.den)
372
            st->time_base = main_timebase;
373
        else {
374
            st->start_time = st->duration = AV_NOPTS_VALUE;
375
        }
376
    }
377 cc0bc648 Reimar Döffinger
    return 0;
378
}
379
380 907a0510 Reimar Döffinger
#define READ_ONE() \
381
    { \
382
        if (!max_interval-- || url_feof(pb)) \
383
            goto out; \
384
        tmp = tmp << 8 | get_byte(pb); \
385
    }
386
387
/**
388
 * \brief resync the stream on the next media packet with specified properties
389
 * \param max_interval how many bytes to search for matching packet at most
390
 * \param track track id the media packet must belong to, -1 for any
391
 * \param timestamp minimum timestamp (== field number) the packet must have, -1 for any
392
 * \return timestamp of packet found
393
 */
394
static int64_t gxf_resync_media(AVFormatContext *s, uint64_t max_interval, int track, int timestamp) {
395
    uint32_t tmp;
396
    uint64_t last_pos;
397
    uint64_t last_found_pos = 0;
398
    int cur_track;
399
    int64_t cur_timestamp = AV_NOPTS_VALUE;
400
    int len;
401
    ByteIOContext *pb = &s->pb;
402
    pkt_type_t type;
403 0019b662 Reimar Döffinger
    tmp = get_be32(pb);
404 907a0510 Reimar Döffinger
start:
405
    while (tmp)
406
        READ_ONE();
407
    READ_ONE();
408
    if (tmp != 1)
409
        goto start;
410
    last_pos = url_ftell(pb);
411
    url_fseek(pb, -5, SEEK_CUR);
412
    if (!parse_packet_header(pb, &type, &len) || type != PKT_MEDIA) {
413
        url_fseek(pb, last_pos, SEEK_SET);
414
        goto start;
415
    }
416
    get_byte(pb);
417
    cur_track = get_byte(pb);
418
    cur_timestamp = get_be32(pb);
419
    last_found_pos = url_ftell(pb) - 16 - 6;
420
    if ((track >= 0 && track != cur_track) || (timestamp >= 0 && timestamp > cur_timestamp)) {
421
        url_fseek(pb, last_pos, SEEK_SET);
422
        goto start;
423
    }
424
out:
425
    if (last_found_pos)
426
        url_fseek(pb, last_found_pos, SEEK_SET);
427
    return cur_timestamp;
428
}
429
430 cc0bc648 Reimar Döffinger
static int gxf_packet(AVFormatContext *s, AVPacket *pkt) {
431
    ByteIOContext *pb = &s->pb;
432
    pkt_type_t pkt_type;
433
    int pkt_len;
434
    while (!url_feof(pb)) {
435
        int track_type, track_id, ret;
436 907a0510 Reimar Döffinger
        int field_nr;
437 cc0bc648 Reimar Döffinger
        if (!parse_packet_header(pb, &pkt_type, &pkt_len)) {
438
            if (!url_feof(pb))
439
                av_log(s, AV_LOG_ERROR, "GXF: sync lost\n");
440
            return -1;
441
        }
442 907a0510 Reimar Döffinger
        if (pkt_type == PKT_FLT) {
443
            gxf_read_index(s, pkt_len);
444
            continue;
445
        }
446 cc0bc648 Reimar Döffinger
        if (pkt_type != PKT_MEDIA) {
447
            url_fskip(pb, pkt_len);
448
            continue;
449
        }
450
        if (pkt_len < 16) {
451
            av_log(s, AV_LOG_ERROR, "GXF: invalid media packet length\n");
452
            continue;
453
        }
454
        pkt_len -= 16;
455
        track_type = get_byte(pb);
456
        track_id = get_byte(pb);
457 907a0510 Reimar Döffinger
        field_nr = get_be32(pb);
458 cc0bc648 Reimar Döffinger
        get_be32(pb); // field information
459
        get_be32(pb); // "timeline" field number
460
        get_byte(pb); // flags
461
        get_byte(pb); // reserved
462
        // NOTE: there is also data length information in the
463 adb0208b Reimar Döffinger
        // field information, it might be better to take this into account
464 cc0bc648 Reimar Döffinger
        // as well.
465
        ret = av_get_packet(pb, pkt, pkt_len);
466
        pkt->stream_index = get_sindex(s, track_id, track_type);
467 b9b18fbd Michael Niedermayer
        pkt->dts = field_nr;
468 cc0bc648 Reimar Döffinger
        return ret;
469
    }
470
    return AVERROR_IO;
471
}
472
473 907a0510 Reimar Döffinger
static int gxf_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags) {
474
    uint64_t pos;
475
    uint64_t maxlen = 100 * 1024 * 1024;
476
    AVStream *st = s->streams[0];
477
    int64_t start_time = s->streams[stream_index]->start_time;
478
    int64_t found;
479
    int idx;
480
    if (timestamp < start_time) timestamp = start_time;
481
    idx = av_index_search_timestamp(st, timestamp - start_time,
482
                                    AVSEEK_FLAG_ANY | AVSEEK_FLAG_BACKWARD);
483
    if (idx < 0)
484
        return -1;
485
    pos = st->index_entries[idx].pos;
486
    if (idx < st->nb_index_entries - 2)
487
        maxlen = st->index_entries[idx + 2].pos - pos;
488
    maxlen = FFMAX(maxlen, 200 * 1024);
489
    url_fseek(&s->pb, pos, SEEK_SET);
490
    found = gxf_resync_media(s, maxlen, -1, timestamp);
491 c26abfa5 Diego Biurrun
    if (FFABS(found - timestamp) > 4)
492 907a0510 Reimar Döffinger
        return -1;
493
    return 0;
494
}
495
496
static int64_t gxf_read_timestamp(AVFormatContext *s, int stream_index,
497
                                  int64_t *pos, int64_t pos_limit) {
498
    ByteIOContext *pb = &s->pb;
499
    int64_t res;
500
    url_fseek(pb, *pos, SEEK_SET);
501
    res = gxf_resync_media(s, pos_limit - *pos, -1, -1);
502
    *pos = url_ftell(pb);
503
    return res;
504
}
505
506 ff70e601 Måns Rullgård
AVInputFormat gxf_demuxer = {
507 cc0bc648 Reimar Döffinger
    "gxf",
508
    "GXF format",
509
    0,
510
    gxf_probe,
511
    gxf_header,
512
    gxf_packet,
513
    NULL,
514 907a0510 Reimar Döffinger
    gxf_seek,
515
    gxf_read_timestamp,
516 cc0bc648 Reimar Döffinger
};