1/* 2 * LXF demuxer 3 * Copyright (c) 2010 Tomas H��rdin 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 "libavutil/intreadwrite.h" 23#include "avformat.h" 24#include "internal.h" 25#include "riff.h" 26 27#define LXF_PACKET_HEADER_SIZE 60 28#define LXF_HEADER_DATA_SIZE 120 29#define LXF_IDENT "LEITCH\0" 30#define LXF_IDENT_LENGTH 8 31#define LXF_SAMPLERATE 48000 32#define LXF_MAX_AUDIO_PACKET (8008*15*4) ///< 15-channel 32-bit NTSC audio frame 33 34static const AVCodecTag lxf_tags[] = { 35 { CODEC_ID_MJPEG, 0 }, 36 { CODEC_ID_MPEG1VIDEO, 1 }, 37 { CODEC_ID_MPEG2VIDEO, 2 }, //MpMl, 4:2:0 38 { CODEC_ID_MPEG2VIDEO, 3 }, //MpPl, 4:2:2 39 { CODEC_ID_DVVIDEO, 4 }, //DV25 40 { CODEC_ID_DVVIDEO, 5 }, //DVCPRO 41 { CODEC_ID_DVVIDEO, 6 }, //DVCPRO50 42 { CODEC_ID_RAWVIDEO, 7 }, //PIX_FMT_ARGB, where alpha is used for chroma keying 43 { CODEC_ID_RAWVIDEO, 8 }, //16-bit chroma key 44 { CODEC_ID_MPEG2VIDEO, 9 }, //4:2:2 CBP ("Constrained Bytes per Gop") 45 { CODEC_ID_NONE, 0 }, 46}; 47 48typedef struct { 49 int channels; ///< number of audio channels. zero means no audio 50 uint8_t temp[LXF_MAX_AUDIO_PACKET]; ///< temp buffer for de-planarizing the audio data 51 int frame_number; ///< current video frame 52} LXFDemuxContext; 53 54static int lxf_probe(AVProbeData *p) 55{ 56 if (!memcmp(p->buf, LXF_IDENT, LXF_IDENT_LENGTH)) 57 return AVPROBE_SCORE_MAX; 58 59 return 0; 60} 61 62/** 63 * Verify the checksum of an LXF packet header 64 * 65 * @param[in] header the packet header to check 66 * @return zero if the checksum is OK, non-zero otherwise 67 */ 68static int check_checksum(const uint8_t *header) 69{ 70 int x; 71 uint32_t sum = 0; 72 73 for (x = 0; x < LXF_PACKET_HEADER_SIZE; x += 4) 74 sum += AV_RL32(&header[x]); 75 76 return sum; 77} 78 79/** 80 * Read input until we find the next ident. If found, copy it to the header buffer 81 * 82 * @param[out] header where to copy the ident to 83 * @return 0 if an ident was found, < 0 on I/O error 84 */ 85static int sync(AVFormatContext *s, uint8_t *header) 86{ 87 uint8_t buf[LXF_IDENT_LENGTH]; 88 int ret; 89 90 if ((ret = avio_read(s->pb, buf, LXF_IDENT_LENGTH)) != LXF_IDENT_LENGTH) 91 return ret < 0 ? ret : AVERROR_EOF; 92 93 while (memcmp(buf, LXF_IDENT, LXF_IDENT_LENGTH)) { 94 if (s->pb->eof_reached) 95 return AVERROR_EOF; 96 97 memmove(buf, &buf[1], LXF_IDENT_LENGTH-1); 98 buf[LXF_IDENT_LENGTH-1] = avio_r8(s->pb); 99 } 100 101 memcpy(header, LXF_IDENT, LXF_IDENT_LENGTH); 102 103 return 0; 104} 105 106/** 107 * Read and checksum the next packet header 108 * 109 * @param[out] header the read packet header 110 * @param[out] format context dependent format information 111 * @return the size of the payload following the header or < 0 on failure 112 */ 113static int get_packet_header(AVFormatContext *s, uint8_t *header, uint32_t *format) 114{ 115 AVIOContext *pb = s->pb; 116 int track_size, samples, ret; 117 AVStream *st; 118 119 //find and read the ident 120 if ((ret = sync(s, header)) < 0) 121 return ret; 122 123 //read the rest of the packet header 124 if ((ret = avio_read(pb, header + LXF_IDENT_LENGTH, 125 LXF_PACKET_HEADER_SIZE - LXF_IDENT_LENGTH)) != 126 LXF_PACKET_HEADER_SIZE - LXF_IDENT_LENGTH) { 127 return ret < 0 ? ret : AVERROR_EOF; 128 } 129 130 if (check_checksum(header)) 131 av_log(s, AV_LOG_ERROR, "checksum error\n"); 132 133 *format = AV_RL32(&header[32]); 134 ret = AV_RL32(&header[36]); 135 136 //type 137 switch (AV_RL32(&header[16])) { 138 case 0: 139 //video 140 //skip VBI data and metadata 141 avio_skip(pb, (int64_t)(uint32_t)AV_RL32(&header[44]) + 142 (int64_t)(uint32_t)AV_RL32(&header[52])); 143 break; 144 case 1: 145 //audio 146 if (!(st = s->streams[1])) { 147 av_log(s, AV_LOG_INFO, "got audio packet, but no audio stream present\n"); 148 break; 149 } 150 151 //set codec based on specified audio bitdepth 152 //we only support tightly packed 16-, 20-, 24- and 32-bit PCM at the moment 153 *format = AV_RL32(&header[40]); 154 st->codec->bits_per_coded_sample = (*format >> 6) & 0x3F; 155 156 if (st->codec->bits_per_coded_sample != (*format & 0x3F)) { 157 av_log(s, AV_LOG_WARNING, "only tightly packed PCM currently supported\n"); 158 return AVERROR_PATCHWELCOME; 159 } 160 161 switch (st->codec->bits_per_coded_sample) { 162 case 16: st->codec->codec_id = CODEC_ID_PCM_S16LE; break; 163 case 20: st->codec->codec_id = CODEC_ID_PCM_LXF; break; 164 case 24: st->codec->codec_id = CODEC_ID_PCM_S24LE; break; 165 case 32: st->codec->codec_id = CODEC_ID_PCM_S32LE; break; 166 default: 167 av_log(s, AV_LOG_WARNING, 168 "only 16-, 20-, 24- and 32-bit PCM currently supported\n"); 169 return AVERROR_PATCHWELCOME; 170 } 171 172 track_size = AV_RL32(&header[48]); 173 samples = track_size * 8 / st->codec->bits_per_coded_sample; 174 175 //use audio packet size to determine video standard 176 //for NTSC we have one 8008-sample audio frame per five video frames 177 if (samples == LXF_SAMPLERATE * 5005 / 30000) { 178 avpriv_set_pts_info(s->streams[0], 64, 1001, 30000); 179 } else { 180 //assume PAL, but warn if we don't have 1920 samples 181 if (samples != LXF_SAMPLERATE / 25) 182 av_log(s, AV_LOG_WARNING, 183 "video doesn't seem to be PAL or NTSC. guessing PAL\n"); 184 185 avpriv_set_pts_info(s->streams[0], 64, 1, 25); 186 } 187 188 //TODO: warning if track mask != (1 << channels) - 1? 189 ret = av_popcount(AV_RL32(&header[44])) * track_size; 190 191 break; 192 default: 193 break; 194 } 195 196 return ret; 197} 198 199static int lxf_read_header(AVFormatContext *s, AVFormatParameters *ap) 200{ 201 LXFDemuxContext *lxf = s->priv_data; 202 AVIOContext *pb = s->pb; 203 uint8_t header[LXF_PACKET_HEADER_SIZE], header_data[LXF_HEADER_DATA_SIZE]; 204 int ret; 205 AVStream *st; 206 uint32_t format, video_params, disk_params; 207 uint16_t record_date, expiration_date; 208 209 if ((ret = get_packet_header(s, header, &format)) < 0) 210 return ret; 211 212 if (ret != LXF_HEADER_DATA_SIZE) { 213 av_log(s, AV_LOG_ERROR, "expected %d B size header, got %d\n", 214 LXF_HEADER_DATA_SIZE, ret); 215 return AVERROR_INVALIDDATA; 216 } 217 218 if ((ret = avio_read(pb, header_data, LXF_HEADER_DATA_SIZE)) != LXF_HEADER_DATA_SIZE) 219 return ret < 0 ? ret : AVERROR_EOF; 220 221 if (!(st = avformat_new_stream(s, NULL))) 222 return AVERROR(ENOMEM); 223 224 st->duration = AV_RL32(&header_data[32]); 225 video_params = AV_RL32(&header_data[40]); 226 record_date = AV_RL16(&header_data[56]); 227 expiration_date = AV_RL16(&header_data[58]); 228 disk_params = AV_RL32(&header_data[116]); 229 230 st->codec->codec_type = AVMEDIA_TYPE_VIDEO; 231 st->codec->bit_rate = 1000000 * ((video_params >> 14) & 0xFF); 232 st->codec->codec_tag = video_params & 0xF; 233 st->codec->codec_id = ff_codec_get_id(lxf_tags, st->codec->codec_tag); 234 235 av_log(s, AV_LOG_DEBUG, "record: %x = %i-%02i-%02i\n", 236 record_date, 1900 + (record_date & 0x7F), (record_date >> 7) & 0xF, 237 (record_date >> 11) & 0x1F); 238 239 av_log(s, AV_LOG_DEBUG, "expire: %x = %i-%02i-%02i\n", 240 expiration_date, 1900 + (expiration_date & 0x7F), (expiration_date >> 7) & 0xF, 241 (expiration_date >> 11) & 0x1F); 242 243 if ((video_params >> 22) & 1) 244 av_log(s, AV_LOG_WARNING, "VBI data not yet supported\n"); 245 246 if ((lxf->channels = (disk_params >> 2) & 0xF)) { 247 if (!(st = avformat_new_stream(s, NULL))) 248 return AVERROR(ENOMEM); 249 250 st->codec->codec_type = AVMEDIA_TYPE_AUDIO; 251 st->codec->sample_rate = LXF_SAMPLERATE; 252 st->codec->channels = lxf->channels; 253 254 avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate); 255 } 256 257 if (format == 1) { 258 //skip extended field data 259 avio_skip(s->pb, (uint32_t)AV_RL32(&header[40])); 260 } 261 262 return 0; 263} 264 265/** 266 * De-planerize the PCM data in lxf->temp 267 * FIXME: remove this once support for planar audio is added to libavcodec 268 * 269 * @param[out] out where to write the de-planerized data to 270 * @param[in] bytes the total size of the PCM data 271 */ 272static void deplanarize(LXFDemuxContext *lxf, AVStream *ast, uint8_t *out, int bytes) 273{ 274 int x, y, z, i, bytes_per_sample = ast->codec->bits_per_coded_sample >> 3; 275 276 for (z = i = 0; z < lxf->channels; z++) 277 for (y = 0; y < bytes / bytes_per_sample / lxf->channels; y++) 278 for (x = 0; x < bytes_per_sample; x++, i++) 279 out[x + bytes_per_sample*(z + y*lxf->channels)] = lxf->temp[i]; 280} 281 282static int lxf_read_packet(AVFormatContext *s, AVPacket *pkt) 283{ 284 LXFDemuxContext *lxf = s->priv_data; 285 AVIOContext *pb = s->pb; 286 uint8_t header[LXF_PACKET_HEADER_SIZE], *buf; 287 AVStream *ast = NULL; 288 uint32_t stream, format; 289 int ret, ret2; 290 291 if ((ret = get_packet_header(s, header, &format)) < 0) 292 return ret; 293 294 stream = AV_RL32(&header[16]); 295 296 if (stream > 1) { 297 av_log(s, AV_LOG_WARNING, "got packet with illegal stream index %u\n", stream); 298 return AVERROR(EAGAIN); 299 } 300 301 if (stream == 1 && !(ast = s->streams[1])) { 302 av_log(s, AV_LOG_ERROR, "got audio packet without having an audio stream\n"); 303 return AVERROR_INVALIDDATA; 304 } 305 306 //make sure the data fits in the de-planerization buffer 307 if (ast && ret > LXF_MAX_AUDIO_PACKET) { 308 av_log(s, AV_LOG_ERROR, "audio packet too large (%i > %i)\n", 309 ret, LXF_MAX_AUDIO_PACKET); 310 return AVERROR_INVALIDDATA; 311 } 312 313 if ((ret2 = av_new_packet(pkt, ret)) < 0) 314 return ret2; 315 316 //read non-20-bit audio data into lxf->temp so we can deplanarize it 317 buf = ast && ast->codec->codec_id != CODEC_ID_PCM_LXF ? lxf->temp : pkt->data; 318 319 if ((ret2 = avio_read(pb, buf, ret)) != ret) { 320 av_free_packet(pkt); 321 return ret2 < 0 ? ret2 : AVERROR_EOF; 322 } 323 324 pkt->stream_index = stream; 325 326 if (ast) { 327 if(ast->codec->codec_id != CODEC_ID_PCM_LXF) 328 deplanarize(lxf, ast, pkt->data, ret); 329 } else { 330 //picture type (0 = closed I, 1 = open I, 2 = P, 3 = B) 331 if (((format >> 22) & 0x3) < 2) 332 pkt->flags |= AV_PKT_FLAG_KEY; 333 334 pkt->dts = lxf->frame_number++; 335 } 336 337 return ret; 338} 339 340AVInputFormat ff_lxf_demuxer = { 341 .name = "lxf", 342 .long_name = NULL_IF_CONFIG_SMALL("VR native stream format (LXF)"), 343 .priv_data_size = sizeof(LXFDemuxContext), 344 .read_probe = lxf_probe, 345 .read_header = lxf_read_header, 346 .read_packet = lxf_read_packet, 347 .codec_tag = (const AVCodecTag* const []){lxf_tags, 0}, 348}; 349 350