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 "demux.h" 28#include "internal.h" 29 30#define LXF_MAX_PACKET_HEADER_SIZE 256 31#define LXF_HEADER_DATA_SIZE 120 32#define LXF_IDENT "LEITCH\0" 33#define LXF_IDENT_LENGTH 8 34#define LXF_SAMPLERATE 48000 35 36static const AVCodecTag lxf_tags[] = { 37 { AV_CODEC_ID_MJPEG, 0 }, 38 { AV_CODEC_ID_MPEG1VIDEO, 1 }, 39 { AV_CODEC_ID_MPEG2VIDEO, 2 }, //MpMl, 4:2:0 40 { AV_CODEC_ID_MPEG2VIDEO, 3 }, //MpPl, 4:2:2 41 { AV_CODEC_ID_DVVIDEO, 4 }, //DV25 42 { AV_CODEC_ID_DVVIDEO, 5 }, //DVCPRO 43 { AV_CODEC_ID_DVVIDEO, 6 }, //DVCPRO50 44 { AV_CODEC_ID_RAWVIDEO, 7 }, //AV_PIX_FMT_ARGB, where alpha is used for chroma keying 45 { AV_CODEC_ID_RAWVIDEO, 8 }, //16-bit chroma key 46 { AV_CODEC_ID_MPEG2VIDEO, 9 }, //4:2:2 CBP ("Constrained Bytes per Gop") 47 { AV_CODEC_ID_NONE, 0 }, 48}; 49 50typedef struct LXFDemuxContext { 51 int channels; ///< number of audio channels. zero means no audio 52 int frame_number; ///< current video frame 53 uint32_t video_format, packet_type, extended_size; 54} LXFDemuxContext; 55 56static int lxf_probe(const AVProbeData *p) 57{ 58 if (!memcmp(p->buf, LXF_IDENT, LXF_IDENT_LENGTH)) 59 return AVPROBE_SCORE_MAX; 60 61 return 0; 62} 63 64/** 65 * Verify the checksum of an LXF packet header 66 * 67 * @param[in] header the packet header to check 68 * @return zero if the checksum is OK, non-zero otherwise 69 */ 70static int check_checksum(const uint8_t *header, int size) 71{ 72 int x; 73 uint32_t sum = 0; 74 75 for (x = 0; x < size; x += 4) 76 sum += AV_RL32(&header[x]); 77 78 return sum; 79} 80 81/** 82 * Read input until we find the next ident. If found, copy it to the header buffer 83 * 84 * @param[out] header where to copy the ident to 85 * @return 0 if an ident was found, < 0 on I/O error 86 */ 87static int lxf_sync(AVFormatContext *s, uint8_t *header) 88{ 89 uint8_t buf[LXF_IDENT_LENGTH]; 90 int ret; 91 92 if ((ret = avio_read(s->pb, buf, LXF_IDENT_LENGTH)) != LXF_IDENT_LENGTH) 93 return ret < 0 ? ret : AVERROR_EOF; 94 95 while (memcmp(buf, LXF_IDENT, LXF_IDENT_LENGTH)) { 96 if (avio_feof(s->pb)) 97 return AVERROR_EOF; 98 99 memmove(buf, &buf[1], LXF_IDENT_LENGTH-1); 100 buf[LXF_IDENT_LENGTH-1] = avio_r8(s->pb); 101 } 102 103 memcpy(header, LXF_IDENT, LXF_IDENT_LENGTH); 104 105 return 0; 106} 107 108/** 109 * Read and checksum the next packet header 110 * 111 * @return the size of the payload following the header or < 0 on failure 112 */ 113static int get_packet_header(AVFormatContext *s) 114{ 115 LXFDemuxContext *lxf = s->priv_data; 116 AVIOContext *pb = s->pb; 117 int track_size, samples, ret; 118 uint32_t version, audio_format, header_size, channels, tmp; 119 AVStream *st; 120 uint8_t header[LXF_MAX_PACKET_HEADER_SIZE]; 121 const uint8_t *p = header + LXF_IDENT_LENGTH; 122 123 //find and read the ident 124 if ((ret = lxf_sync(s, header)) < 0) 125 return ret; 126 127 ret = avio_read(pb, header + LXF_IDENT_LENGTH, 8); 128 if (ret != 8) 129 return ret < 0 ? ret : AVERROR_EOF; 130 131 version = bytestream_get_le32(&p); 132 header_size = bytestream_get_le32(&p); 133 if (version > 1) 134 avpriv_request_sample(s, "Format version %"PRIu32, version); 135 136 if (header_size < (version ? 72 : 60) || 137 header_size > LXF_MAX_PACKET_HEADER_SIZE || 138 (header_size & 3)) { 139 av_log(s, AV_LOG_ERROR, "Invalid header size 0x%"PRIx32"\n", header_size); 140 return AVERROR_INVALIDDATA; 141 } 142 143 //read the rest of the packet header 144 if ((ret = avio_read(pb, header + (p - header), 145 header_size - (p - header))) != 146 header_size - (p - header)) 147 return ret < 0 ? ret : AVERROR_EOF; 148 149 if (check_checksum(header, header_size)) 150 av_log(s, AV_LOG_ERROR, "checksum error\n"); 151 152 lxf->packet_type = bytestream_get_le32(&p); 153 p += version ? 20 : 12; 154 155 lxf->extended_size = 0; 156 switch (lxf->packet_type) { 157 case 0: 158 //video 159 lxf->video_format = bytestream_get_le32(&p); 160 ret = bytestream_get_le32(&p); 161 //skip VBI data and metadata 162 avio_skip(pb, (int64_t)(uint32_t)AV_RL32(p + 4) + 163 (int64_t)(uint32_t)AV_RL32(p + 12)); 164 break; 165 case 1: 166 //audio 167 if (s->nb_streams < 2) { 168 av_log(s, AV_LOG_INFO, "got audio packet, but no audio stream present\n"); 169 break; 170 } 171 172 if (version == 0) 173 p += 8; 174 audio_format = bytestream_get_le32(&p); 175 channels = bytestream_get_le32(&p); 176 track_size = bytestream_get_le32(&p); 177 178 st = s->streams[1]; 179 180 //set codec based on specified audio bitdepth 181 //we only support tightly packed 16-, 20-, 24- and 32-bit PCM at the moment 182 st->codecpar->bits_per_coded_sample = (audio_format >> 6) & 0x3F; 183 184 if (st->codecpar->bits_per_coded_sample != (audio_format & 0x3F)) { 185 avpriv_report_missing_feature(s, "Not tightly packed PCM"); 186 return AVERROR_PATCHWELCOME; 187 } 188 189 switch (st->codecpar->bits_per_coded_sample) { 190 case 16: st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE_PLANAR; break; 191 case 20: st->codecpar->codec_id = AV_CODEC_ID_PCM_LXF; break; 192 case 24: st->codecpar->codec_id = AV_CODEC_ID_PCM_S24LE_PLANAR; break; 193 case 32: st->codecpar->codec_id = AV_CODEC_ID_PCM_S32LE_PLANAR; break; 194 default: 195 avpriv_report_missing_feature(s, "PCM not 16-, 20-, 24- or 32-bits"); 196 return AVERROR_PATCHWELCOME; 197 } 198 199 samples = track_size * 8LL / st->codecpar->bits_per_coded_sample; 200 201 //use audio packet size to determine video standard 202 //for NTSC we have one 8008-sample audio frame per five video frames 203 if (samples == LXF_SAMPLERATE * 5005 / 30000) { 204 avpriv_set_pts_info(s->streams[0], 64, 1001, 30000); 205 } else { 206 //assume PAL, but warn if we don't have 1920 samples 207 if (samples != LXF_SAMPLERATE / 25) 208 av_log(s, AV_LOG_WARNING, 209 "video doesn't seem to be PAL or NTSC. guessing PAL\n"); 210 211 avpriv_set_pts_info(s->streams[0], 64, 1, 25); 212 } 213 214 if (av_popcount(channels) * (uint64_t)track_size > INT_MAX) 215 return AVERROR_INVALIDDATA; 216 //TODO: warning if track mask != (1 << channels) - 1? 217 ret = av_popcount(channels) * track_size; 218 219 break; 220 default: 221 tmp = bytestream_get_le32(&p); 222 ret = bytestream_get_le32(&p); 223 if (tmp == 1) 224 lxf->extended_size = bytestream_get_le32(&p); 225 break; 226 } 227 228 return ret; 229} 230 231static int lxf_read_header(AVFormatContext *s) 232{ 233 LXFDemuxContext *lxf = s->priv_data; 234 AVIOContext *pb = s->pb; 235 uint8_t header_data[LXF_HEADER_DATA_SIZE]; 236 int ret; 237 AVStream *st; 238 uint32_t video_params, disk_params; 239 uint16_t record_date, expiration_date; 240 241 if ((ret = get_packet_header(s)) < 0) 242 return ret; 243 244 if (ret != LXF_HEADER_DATA_SIZE) { 245 av_log(s, AV_LOG_ERROR, "expected %d B size header, got %d\n", 246 LXF_HEADER_DATA_SIZE, ret); 247 return AVERROR_INVALIDDATA; 248 } 249 250 if ((ret = avio_read(pb, header_data, LXF_HEADER_DATA_SIZE)) != LXF_HEADER_DATA_SIZE) 251 return ret < 0 ? ret : AVERROR_EOF; 252 253 if (!(st = avformat_new_stream(s, NULL))) 254 return AVERROR(ENOMEM); 255 256 st->duration = AV_RL32(&header_data[32]); 257 video_params = AV_RL32(&header_data[40]); 258 record_date = AV_RL16(&header_data[56]); 259 expiration_date = AV_RL16(&header_data[58]); 260 disk_params = AV_RL32(&header_data[116]); 261 262 st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO; 263 st->codecpar->bit_rate = 1000000 * ((video_params >> 14) & 0xFF); 264 st->codecpar->codec_tag = video_params & 0xF; 265 st->codecpar->codec_id = ff_codec_get_id(lxf_tags, st->codecpar->codec_tag); 266 ffstream(st)->need_parsing = AVSTREAM_PARSE_HEADERS; 267 268 av_log(s, AV_LOG_DEBUG, "record: %x = %i-%02i-%02i\n", 269 record_date, 1900 + (record_date & 0x7F), (record_date >> 7) & 0xF, 270 (record_date >> 11) & 0x1F); 271 272 av_log(s, AV_LOG_DEBUG, "expire: %x = %i-%02i-%02i\n", 273 expiration_date, 1900 + (expiration_date & 0x7F), (expiration_date >> 7) & 0xF, 274 (expiration_date >> 11) & 0x1F); 275 276 if ((video_params >> 22) & 1) 277 av_log(s, AV_LOG_WARNING, "VBI data not yet supported\n"); 278 279 if ((lxf->channels = 1 << (disk_params >> 4 & 3) + 1)) { 280 if (!(st = avformat_new_stream(s, NULL))) 281 return AVERROR(ENOMEM); 282 283 st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO; 284 st->codecpar->sample_rate = LXF_SAMPLERATE; 285 st->codecpar->ch_layout.nb_channels = lxf->channels; 286 287 avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate); 288 } 289 290 avio_skip(s->pb, lxf->extended_size); 291 292 return 0; 293} 294 295static int lxf_read_packet(AVFormatContext *s, AVPacket *pkt) 296{ 297 LXFDemuxContext *lxf = s->priv_data; 298 AVIOContext *pb = s->pb; 299 uint32_t stream; 300 int ret, ret2; 301 302 if ((ret = get_packet_header(s)) < 0) 303 return ret; 304 305 stream = lxf->packet_type; 306 307 if (stream > 1) { 308 av_log(s, AV_LOG_WARNING, 309 "got packet with illegal stream index %"PRIu32"\n", stream); 310 return FFERROR_REDO; 311 } 312 313 if (stream == 1 && s->nb_streams < 2) { 314 av_log(s, AV_LOG_ERROR, "got audio packet without having an audio stream\n"); 315 return AVERROR_INVALIDDATA; 316 } 317 318 if ((ret2 = av_new_packet(pkt, ret)) < 0) 319 return ret2; 320 321 if ((ret2 = avio_read(pb, pkt->data, ret)) != ret) { 322 return ret2 < 0 ? ret2 : AVERROR_EOF; 323 } 324 325 pkt->stream_index = stream; 326 327 if (!stream) { 328 //picture type (0 = closed I, 1 = open I, 2 = P, 3 = B) 329 if (((lxf->video_format >> 22) & 0x3) < 2) 330 pkt->flags |= AV_PKT_FLAG_KEY; 331 332 pkt->dts = lxf->frame_number++; 333 } 334 335 return ret; 336} 337 338const AVInputFormat ff_lxf_demuxer = { 339 .name = "lxf", 340 .long_name = NULL_IF_CONFIG_SMALL("VR native stream (LXF)"), 341 .priv_data_size = sizeof(LXFDemuxContext), 342 .read_probe = lxf_probe, 343 .read_header = lxf_read_header, 344 .read_packet = lxf_read_packet, 345 .codec_tag = (const AVCodecTag* const []){lxf_tags, 0}, 346}; 347