/* * LXF demuxer * Copyright (c) 2010 Tomas Härdin * * This file is part of Libav. * * Libav is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * Libav is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include <inttypes.h> #include "libavutil/intreadwrite.h" #include "libavcodec/bytestream.h" #include "avformat.h" #include "internal.h" #define LXF_MAX_PACKET_HEADER_SIZE 256 #define LXF_HEADER_DATA_SIZE 120 #define LXF_IDENT "LEITCH\0" #define LXF_IDENT_LENGTH 8 #define LXF_SAMPLERATE 48000 static const AVCodecTag lxf_tags[] = { { AV_CODEC_ID_MJPEG, 0 }, { AV_CODEC_ID_MPEG1VIDEO, 1 }, { AV_CODEC_ID_MPEG2VIDEO, 2 }, //MpMl, 4:2:0 { AV_CODEC_ID_MPEG2VIDEO, 3 }, //MpPl, 4:2:2 { AV_CODEC_ID_DVVIDEO, 4 }, //DV25 { AV_CODEC_ID_DVVIDEO, 5 }, //DVCPRO { AV_CODEC_ID_DVVIDEO, 6 }, //DVCPRO50 { AV_CODEC_ID_RAWVIDEO, 7 }, //AV_PIX_FMT_ARGB, where alpha is used for chroma keying { AV_CODEC_ID_RAWVIDEO, 8 }, //16-bit chroma key { AV_CODEC_ID_MPEG2VIDEO, 9 }, //4:2:2 CBP ("Constrained Bytes per Gop") { AV_CODEC_ID_NONE, 0 }, }; typedef struct LXFDemuxContext { int channels; ///< number of audio channels. zero means no audio int frame_number; ///< current video frame uint32_t video_format, packet_type, extended_size; } LXFDemuxContext; static int lxf_probe(AVProbeData *p) { if (!memcmp(p->buf, LXF_IDENT, LXF_IDENT_LENGTH)) return AVPROBE_SCORE_MAX; return 0; } /** * Verify the checksum of an LXF packet header * * @param[in] header the packet header to check * @return zero if the checksum is OK, non-zero otherwise */ static int check_checksum(const uint8_t *header, int size) { int x; uint32_t sum = 0; for (x = 0; x < size; x += 4) sum += AV_RL32(&header[x]); return sum; } /** * Read input until we find the next ident. If found, copy it to the header buffer * * @param[out] header where to copy the ident to * @return 0 if an ident was found, < 0 on I/O error */ static int sync(AVFormatContext *s, uint8_t *header) { uint8_t buf[LXF_IDENT_LENGTH]; int ret; if ((ret = avio_read(s->pb, buf, LXF_IDENT_LENGTH)) != LXF_IDENT_LENGTH) return ret < 0 ? ret : AVERROR_EOF; while (memcmp(buf, LXF_IDENT, LXF_IDENT_LENGTH)) { if (s->pb->eof_reached) return AVERROR_EOF; memmove(buf, &buf[1], LXF_IDENT_LENGTH-1); buf[LXF_IDENT_LENGTH-1] = avio_r8(s->pb); } memcpy(header, LXF_IDENT, LXF_IDENT_LENGTH); return 0; } /** * Read and checksum the next packet header * * @return the size of the payload following the header or < 0 on failure */ static int get_packet_header(AVFormatContext *s) { LXFDemuxContext *lxf = s->priv_data; AVIOContext *pb = s->pb; int track_size, samples, ret; uint32_t version, audio_format, header_size, channels, tmp; AVStream *st; uint8_t header[LXF_MAX_PACKET_HEADER_SIZE]; const uint8_t *p = header + LXF_IDENT_LENGTH; //find and read the ident if ((ret = sync(s, header)) < 0) return ret; ret = avio_read(pb, header + LXF_IDENT_LENGTH, 8); if (ret != 8) return ret < 0 ? ret : AVERROR_EOF; version = bytestream_get_le32(&p); header_size = bytestream_get_le32(&p); if (version > 1) avpriv_request_sample(s, "Format version %"PRIu32, version); if (header_size < (version ? 72 : 60) || header_size > LXF_MAX_PACKET_HEADER_SIZE || (header_size & 3)) { av_log(s, AV_LOG_ERROR, "Invalid header size 0x%"PRIx32"\n", header_size); return AVERROR_INVALIDDATA; } //read the rest of the packet header ret = avio_read(pb, header + (p - header), header_size - (p - header)); if (ret != header_size - (p - header)) return ret < 0 ? ret : AVERROR_EOF; if (check_checksum(header, header_size)) av_log(s, AV_LOG_ERROR, "checksum error\n"); lxf->packet_type = bytestream_get_le32(&p); p += version ? 20 : 12; lxf->extended_size = 0; switch (lxf->packet_type) { case 0: //video lxf->video_format = bytestream_get_le32(&p); ret = bytestream_get_le32(&p); //skip VBI data and metadata avio_skip(pb, (int64_t)(uint32_t)AV_RL32(p + 4) + (int64_t)(uint32_t)AV_RL32(p + 12)); break; case 1: //audio if (s->nb_streams < 2) { av_log(s, AV_LOG_INFO, "got audio packet, but no audio stream present\n"); break; } if (version == 0) p += 8; audio_format = bytestream_get_le32(&p); channels = bytestream_get_le32(&p); track_size = bytestream_get_le32(&p); st = s->streams[1]; //set codec based on specified audio bitdepth //we only support tightly packed 16-, 20-, 24- and 32-bit PCM at the moment st->codec->bits_per_coded_sample = (audio_format >> 6) & 0x3F; if (st->codec->bits_per_coded_sample != (audio_format & 0x3F)) { av_log(s, AV_LOG_WARNING, "only tightly packed PCM currently supported\n"); return AVERROR_PATCHWELCOME; } switch (st->codec->bits_per_coded_sample) { case 16: st->codec->codec_id = AV_CODEC_ID_PCM_S16LE_PLANAR; break; case 20: st->codec->codec_id = AV_CODEC_ID_PCM_LXF; break; case 24: st->codec->codec_id = AV_CODEC_ID_PCM_S24LE_PLANAR; break; case 32: st->codec->codec_id = AV_CODEC_ID_PCM_S32LE_PLANAR; break; default: av_log(s, AV_LOG_WARNING, "only 16-, 20-, 24- and 32-bit PCM currently supported\n"); return AVERROR_PATCHWELCOME; } samples = track_size * 8 / st->codec->bits_per_coded_sample; //use audio packet size to determine video standard //for NTSC we have one 8008-sample audio frame per five video frames if (samples == LXF_SAMPLERATE * 5005 / 30000) { avpriv_set_pts_info(s->streams[0], 64, 1001, 30000); } else { //assume PAL, but warn if we don't have 1920 samples if (samples != LXF_SAMPLERATE / 25) av_log(s, AV_LOG_WARNING, "video doesn't seem to be PAL or NTSC. guessing PAL\n"); avpriv_set_pts_info(s->streams[0], 64, 1, 25); } //TODO: warning if track mask != (1 << channels) - 1? ret = av_popcount(channels) * track_size; break; default: tmp = bytestream_get_le32(&p); ret = bytestream_get_le32(&p); if (tmp == 1) lxf->extended_size = bytestream_get_le32(&p); break; } return ret; } static int lxf_read_header(AVFormatContext *s) { LXFDemuxContext *lxf = s->priv_data; AVIOContext *pb = s->pb; uint8_t header_data[LXF_HEADER_DATA_SIZE]; int ret; AVStream *st; uint32_t video_params, disk_params; uint16_t record_date, expiration_date; if ((ret = get_packet_header(s)) < 0) return ret; if (ret != LXF_HEADER_DATA_SIZE) { av_log(s, AV_LOG_ERROR, "expected %d B size header, got %d\n", LXF_HEADER_DATA_SIZE, ret); return AVERROR_INVALIDDATA; } if ((ret = avio_read(pb, header_data, LXF_HEADER_DATA_SIZE)) != LXF_HEADER_DATA_SIZE) return ret < 0 ? ret : AVERROR_EOF; if (!(st = avformat_new_stream(s, NULL))) return AVERROR(ENOMEM); st->duration = AV_RL32(&header_data[32]); video_params = AV_RL32(&header_data[40]); record_date = AV_RL16(&header_data[56]); expiration_date = AV_RL16(&header_data[58]); disk_params = AV_RL32(&header_data[116]); st->codec->codec_type = AVMEDIA_TYPE_VIDEO; st->codec->bit_rate = 1000000 * ((video_params >> 14) & 0xFF); st->codec->codec_tag = video_params & 0xF; st->codec->codec_id = ff_codec_get_id(lxf_tags, st->codec->codec_tag); av_log(s, AV_LOG_DEBUG, "record: %x = %i-%02i-%02i\n", record_date, 1900 + (record_date & 0x7F), (record_date >> 7) & 0xF, (record_date >> 11) & 0x1F); av_log(s, AV_LOG_DEBUG, "expire: %x = %i-%02i-%02i\n", expiration_date, 1900 + (expiration_date & 0x7F), (expiration_date >> 7) & 0xF, (expiration_date >> 11) & 0x1F); if ((video_params >> 22) & 1) av_log(s, AV_LOG_WARNING, "VBI data not yet supported\n"); if ((lxf->channels = 1 << (disk_params >> 4 & 3) + 1)) { if (!(st = avformat_new_stream(s, NULL))) return AVERROR(ENOMEM); st->codec->codec_type = AVMEDIA_TYPE_AUDIO; st->codec->sample_rate = LXF_SAMPLERATE; st->codec->channels = lxf->channels; avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate); } avio_skip(s->pb, lxf->extended_size); return 0; } static int lxf_read_packet(AVFormatContext *s, AVPacket *pkt) { LXFDemuxContext *lxf = s->priv_data; AVIOContext *pb = s->pb; uint32_t stream; int ret, ret2; if ((ret = get_packet_header(s)) < 0) return ret; stream = lxf->packet_type; if (stream > 1) { av_log(s, AV_LOG_WARNING, "got packet with illegal stream index %"PRIu32"\n", stream); return AVERROR(EAGAIN); } if (stream == 1 && s->nb_streams < 2) { av_log(s, AV_LOG_ERROR, "got audio packet without having an audio stream\n"); return AVERROR_INVALIDDATA; } if ((ret2 = av_new_packet(pkt, ret)) < 0) return ret2; if ((ret2 = avio_read(pb, pkt->data, ret)) != ret) { av_packet_unref(pkt); return ret2 < 0 ? ret2 : AVERROR_EOF; } pkt->stream_index = stream; if (!stream) { //picture type (0 = closed I, 1 = open I, 2 = P, 3 = B) if (((lxf->video_format >> 22) & 0x3) < 2) pkt->flags |= AV_PKT_FLAG_KEY; pkt->dts = lxf->frame_number++; } return ret; } AVInputFormat ff_lxf_demuxer = { .name = "lxf", .long_name = NULL_IF_CONFIG_SMALL("VR native stream (LXF)"), .priv_data_size = sizeof(LXFDemuxContext), .read_probe = lxf_probe, .read_header = lxf_read_header, .read_packet = lxf_read_packet, .codec_tag = (const AVCodecTag* const []){lxf_tags, 0}, };