From 8992cb1d0d07edc33d274f6d7924ecdf6f83d994 Mon Sep 17 00:00:00 2001 From: Tim Redfern Date: Thu, 5 Sep 2013 17:57:22 +0100 Subject: making act segmenter --- ffmpeg/libavformat/lxfdec.c | 348 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 348 insertions(+) create mode 100644 ffmpeg/libavformat/lxfdec.c (limited to 'ffmpeg/libavformat/lxfdec.c') diff --git a/ffmpeg/libavformat/lxfdec.c b/ffmpeg/libavformat/lxfdec.c new file mode 100644 index 0000000..876f988 --- /dev/null +++ b/ffmpeg/libavformat/lxfdec.c @@ -0,0 +1,348 @@ +/* + * LXF demuxer + * Copyright (c) 2010 Tomas Härdin + * + * This file is part of FFmpeg. + * + * FFmpeg 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. + * + * FFmpeg 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 FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#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 +#define LXF_MAX_AUDIO_PACKET (8008*15*4) ///< 15-channel 32-bit NTSC audio frame + +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 { + 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 (url_feof(s->pb)) + 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; + + //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; + + p = header + LXF_IDENT_LENGTH; + version = bytestream_get_le32(&p); + header_size = bytestream_get_le32(&p); + if (version > 1) + avpriv_request_sample(s, "format version %i", 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%x\n", header_size); + return AVERROR_INVALIDDATA; + } + + //read the rest of the packet header + if ((ret = avio_read(pb, header + (p - header), + header_size - (p - header))) != + 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->streams || !(st = s->streams[1])) { + 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); + + //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; + AVStream *ast = NULL; + 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 %u\n", stream); + return AVERROR(EAGAIN); + } + + if (stream == 1 && !(ast = s->streams[1])) { + av_log(s, AV_LOG_ERROR, "got audio packet without having an audio stream\n"); + return AVERROR_INVALIDDATA; + } + + //make sure the data fits in the de-planerization buffer + if (ast && ret > LXF_MAX_AUDIO_PACKET) { + av_log(s, AV_LOG_ERROR, "audio packet too large (%i > %i)\n", + ret, LXF_MAX_AUDIO_PACKET); + return AVERROR_INVALIDDATA; + } + + if ((ret2 = av_new_packet(pkt, ret)) < 0) + return ret2; + + if ((ret2 = avio_read(pb, pkt->data, ret)) != ret) { + av_free_packet(pkt); + return ret2 < 0 ? ret2 : AVERROR_EOF; + } + + pkt->stream_index = stream; + + if (!ast) { + //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}, +}; -- cgit v1.2.3