libavformat/lxfdec.c

   1 /*
   2  * LXF demuxer
   3  * Copyright (c) 2010 Tomas Härdin
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav 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  * Libav 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 Libav; 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
  55 static int lxf_probe(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 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 (s->pb->eof_reached)
  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  */
 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 = 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     ret = avio_read(pb, header + (p - header), header_size - (p - header));
 144     if (ret != header_size - (p - header))
 145         return ret < 0 ? ret : AVERROR_EOF;
 146
 147     if (check_checksum(header, header_size))
 148         av_log(s, AV_LOG_ERROR, "checksum error\n");
 149
 150     lxf->packet_type = bytestream_get_le32(&p);
 151     p += version ? 20 : 12;
 152
 153     lxf->extended_size = 0;
 154     switch (lxf->packet_type) {
 155     case 0:
 156         //video
 157         lxf->video_format = bytestream_get_le32(&p);
 158         ret               = bytestream_get_le32(&p);
 159         //skip VBI data and metadata
 160         avio_skip(pb, (int64_t)(uint32_t)AV_RL32(p + 4) +
 161                       (int64_t)(uint32_t)AV_RL32(p + 12));
 162         break;
 163     case 1:
 164         //audio
 165         if (s->nb_streams < 2) {
 166             av_log(s, AV_LOG_INFO, "got audio packet, but no audio stream present\n");
 167             break;
 168         }
 169
 170         if (version == 0)
 171             p += 8;
 172         audio_format = bytestream_get_le32(&p);
 173         channels     = bytestream_get_le32(&p);
 174         track_size   = bytestream_get_le32(&p);
 175
 176         st = s->streams[1];
 177
 178         //set codec based on specified audio bitdepth
 179         //we only support tightly packed 16-, 20-, 24- and 32-bit PCM at the moment
 180         st->codecpar->bits_per_coded_sample = (audio_format >> 6) & 0x3F;
 181
 182         if (st->codecpar->bits_per_coded_sample != (audio_format & 0x3F)) {
 183             avpriv_report_missing_feature(s, "Not tightly packed PCM");
 184             return AVERROR_PATCHWELCOME;
 185         }
 186
 187         switch (st->codecpar->bits_per_coded_sample) {
 188         case 16: st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE_PLANAR; break;
 189         case 20: st->codecpar->codec_id = AV_CODEC_ID_PCM_LXF;   break;
 190         case 24: st->codecpar->codec_id = AV_CODEC_ID_PCM_S24LE_PLANAR; break;
 191         case 32: st->codecpar->codec_id = AV_CODEC_ID_PCM_S32LE_PLANAR; break;
 192         default:
 193             avpriv_report_missing_feature(s, "PCM not 16-, 20-, 24- or 32-bits");
 194             return AVERROR_PATCHWELCOME;
 195         }
 196
 197         samples = track_size * 8 / st->codecpar->bits_per_coded_sample;
 198
 199         //use audio packet size to determine video standard
 200         //for NTSC we have one 8008-sample audio frame per five video frames
 201         if (samples == LXF_SAMPLERATE * 5005 / 30000) {
 202             avpriv_set_pts_info(s->streams[0], 64, 1001, 30000);
 203         } else {
 204             //assume PAL, but warn if we don't have 1920 samples
 205             if (samples != LXF_SAMPLERATE / 25)
 206                 av_log(s, AV_LOG_WARNING,
 207                        "video doesn't seem to be PAL or NTSC. guessing PAL\n");
 208
 209             avpriv_set_pts_info(s->streams[0], 64, 1, 25);
 210         }
 211
 212         //TODO: warning if track mask != (1 << channels) - 1?
 213         ret = av_popcount(channels) * track_size;
 214
 215         break;
 216     default:
 217         tmp = bytestream_get_le32(&p);
 218         ret = bytestream_get_le32(&p);
 219         if (tmp == 1)
 220             lxf->extended_size = bytestream_get_le32(&p);
 221         break;
 222     }
 223
 224     return ret;
 225 }
 226
 227 static int lxf_read_header(AVFormatContext *s)
 228 {
 229     LXFDemuxContext *lxf = s->priv_data;
 230     AVIOContext   *pb  = s->pb;
 231     uint8_t header_data[LXF_HEADER_DATA_SIZE];
 232     int ret;
 233     AVStream *st;
 234     uint32_t video_params, disk_params;
 235     uint16_t record_date, expiration_date;
 236
 237     if ((ret = get_packet_header(s)) < 0)
 238         return ret;
 239
 240     if (ret != LXF_HEADER_DATA_SIZE) {
 241         av_log(s, AV_LOG_ERROR, "expected %d B size header, got %d\n",
 242                LXF_HEADER_DATA_SIZE, ret);
 243         return AVERROR_INVALIDDATA;
 244     }
 245
 246     if ((ret = avio_read(pb, header_data, LXF_HEADER_DATA_SIZE)) != LXF_HEADER_DATA_SIZE)
 247         return ret < 0 ? ret : AVERROR_EOF;
 248
 249     if (!(st = avformat_new_stream(s, NULL)))
 250         return AVERROR(ENOMEM);
 251
 252     st->duration          = AV_RL32(&header_data[32]);
 253     video_params          = AV_RL32(&header_data[40]);
 254     record_date           = AV_RL16(&header_data[56]);
 255     expiration_date       = AV_RL16(&header_data[58]);
 256     disk_params           = AV_RL32(&header_data[116]);
 257
 258     st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
 259     st->codecpar->bit_rate   = 1000000 * ((video_params >> 14) & 0xFF);
 260     st->codecpar->codec_tag  = video_params & 0xF;
 261     st->codecpar->codec_id   = ff_codec_get_id(lxf_tags, st->codecpar->codec_tag);
 262
 263     av_log(s, AV_LOG_DEBUG, "record: %x = %i-%02i-%02i\n",
 264            record_date, 1900 + (record_date & 0x7F), (record_date >> 7) & 0xF,
 265            (record_date >> 11) & 0x1F);
 266
 267     av_log(s, AV_LOG_DEBUG, "expire: %x = %i-%02i-%02i\n",
 268            expiration_date, 1900 + (expiration_date & 0x7F), (expiration_date >> 7) & 0xF,
 269            (expiration_date >> 11) & 0x1F);
 270
 271     if ((video_params >> 22) & 1)
 272         av_log(s, AV_LOG_WARNING, "VBI data not yet supported\n");
 273
 274     if ((lxf->channels = 1 << (disk_params >> 4 & 3) + 1)) {
 275         if (!(st = avformat_new_stream(s, NULL)))
 276             return AVERROR(ENOMEM);
 277
 278         st->codecpar->codec_type  = AVMEDIA_TYPE_AUDIO;
 279         st->codecpar->sample_rate = LXF_SAMPLERATE;
 280         st->codecpar->channels    = lxf->channels;
 281
 282         avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
 283     }
 284
 285     avio_skip(s->pb, lxf->extended_size);
 286
 287     return 0;
 288 }
 289
 290 static int lxf_read_packet(AVFormatContext *s, AVPacket *pkt)
 291 {
 292     LXFDemuxContext *lxf = s->priv_data;
 293     AVIOContext   *pb  = s->pb;
 294     uint32_t stream;
 295     int ret, ret2;
 296
 297     if ((ret = get_packet_header(s)) < 0)
 298         return ret;
 299
 300     stream = lxf->packet_type;
 301
 302     if (stream > 1) {
 303         av_log(s, AV_LOG_WARNING,
 304                "got packet with illegal stream index %"PRIu32"\n", stream);
 305         return AVERROR(EAGAIN);
 306     }
 307
 308     if (stream == 1 && s->nb_streams < 2) {
 309         av_log(s, AV_LOG_ERROR, "got audio packet without having an audio stream\n");
 310         return AVERROR_INVALIDDATA;
 311     }
 312
 313     if ((ret2 = av_new_packet(pkt, ret)) < 0)
 314         return ret2;
 315
 316     if ((ret2 = avio_read(pb, pkt->data, ret)) != ret) {
 317         av_packet_unref(pkt);
 318         return ret2 < 0 ? ret2 : AVERROR_EOF;
 319     }
 320
 321     pkt->stream_index = stream;
 322
 323     if (!stream) {
 324         //picture type (0 = closed I, 1 = open I, 2 = P, 3 = B)
 325         if (((lxf->video_format >> 22) & 0x3) < 2)
 326             pkt->flags |= AV_PKT_FLAG_KEY;
 327
 328         pkt->dts = lxf->frame_number++;
 329     }
 330
 331     return ret;
 332 }
 333
 334 AVInputFormat ff_lxf_demuxer = {
 335     .name           = "lxf",
 336     .long_name      = NULL_IF_CONFIG_SMALL("VR native stream (LXF)"),
 337     .priv_data_size = sizeof(LXFDemuxContext),
 338     .read_probe     = lxf_probe,
 339     .read_header    = lxf_read_header,
 340     .read_packet    = lxf_read_packet,
 341     .codec_tag      = (const AVCodecTag* const []){lxf_tags, 0},
 342 };