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/gxf.c | 596 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 596 insertions(+) create mode 100644 ffmpeg/libavformat/gxf.c (limited to 'ffmpeg/libavformat/gxf.c') diff --git a/ffmpeg/libavformat/gxf.c b/ffmpeg/libavformat/gxf.c new file mode 100644 index 0000000..86e6291 --- /dev/null +++ b/ffmpeg/libavformat/gxf.c @@ -0,0 +1,596 @@ +/* + * GXF demuxer. + * Copyright (c) 2006 Reimar Doeffinger + * + * 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/channel_layout.h" +#include "libavutil/common.h" +#include "avformat.h" +#include "internal.h" +#include "gxf.h" +#include "libavcodec/mpeg12data.h" + +struct gxf_stream_info { + int64_t first_field; + int64_t last_field; + AVRational frames_per_second; + int32_t fields_per_frame; + int64_t track_aux_data; +}; + +/** + * @brief parse gxf timecode and add it to metadata + */ +static int add_timecode_metadata(AVDictionary **pm, const char *key, uint32_t timecode, int fields_per_frame) +{ + char tmp[128]; + int field = timecode & 0xff; + int frame = fields_per_frame ? field / fields_per_frame : field; + int second = (timecode >> 8) & 0xff; + int minute = (timecode >> 16) & 0xff; + int hour = (timecode >> 24) & 0x1f; + int drop = (timecode >> 29) & 1; + // bit 30: color_frame, unused + // ignore invalid time code + if (timecode >> 31) + return 0; + snprintf(tmp, sizeof(tmp), "%02d:%02d:%02d%c%02d", + hour, minute, second, drop ? ';' : ':', frame); + return av_dict_set(pm, key, tmp, 0); +} + +/** + * @brief parses a packet header, extracting type and length + * @param pb AVIOContext to read header from + * @param type detected packet type is stored here + * @param length detected packet length, excluding header is stored here + * @return 0 if header not found or contains invalid data, 1 otherwise + */ +static int parse_packet_header(AVIOContext *pb, GXFPktType *type, int *length) { + if (avio_rb32(pb)) + return 0; + if (avio_r8(pb) != 1) + return 0; + *type = avio_r8(pb); + *length = avio_rb32(pb); + if ((*length >> 24) || *length < 16) + return 0; + *length -= 16; + if (avio_rb32(pb)) + return 0; + if (avio_r8(pb) != 0xe1) + return 0; + if (avio_r8(pb) != 0xe2) + return 0; + return 1; +} + +/** + * @brief check if file starts with a PKT_MAP header + */ +static int gxf_probe(AVProbeData *p) { + static const uint8_t startcode[] = {0, 0, 0, 0, 1, 0xbc}; // start with map packet + static const uint8_t endcode[] = {0, 0, 0, 0, 0xe1, 0xe2}; + if (!memcmp(p->buf, startcode, sizeof(startcode)) && + !memcmp(&p->buf[16 - sizeof(endcode)], endcode, sizeof(endcode))) + return AVPROBE_SCORE_MAX; + return 0; +} + +/** + * @brief gets the stream index for the track with the specified id, creates new + * stream if not found + * @param id id of stream to find / add + * @param format stream format identifier + */ +static int get_sindex(AVFormatContext *s, int id, int format) { + int i; + AVStream *st = NULL; + i = ff_find_stream_index(s, id); + if (i >= 0) + return i; + st = avformat_new_stream(s, NULL); + if (!st) + return AVERROR(ENOMEM); + st->id = id; + switch (format) { + case 3: + case 4: + st->codec->codec_type = AVMEDIA_TYPE_VIDEO; + st->codec->codec_id = AV_CODEC_ID_MJPEG; + break; + case 13: + case 15: + st->codec->codec_type = AVMEDIA_TYPE_VIDEO; + st->codec->codec_id = AV_CODEC_ID_DVVIDEO; + break; + case 14: + case 16: + st->codec->codec_type = AVMEDIA_TYPE_VIDEO; + st->codec->codec_id = AV_CODEC_ID_DVVIDEO; + break; + case 11: + case 12: + case 20: + st->codec->codec_type = AVMEDIA_TYPE_VIDEO; + st->codec->codec_id = AV_CODEC_ID_MPEG2VIDEO; + st->need_parsing = AVSTREAM_PARSE_HEADERS; //get keyframe flag etc. + break; + case 22: + case 23: + st->codec->codec_type = AVMEDIA_TYPE_VIDEO; + st->codec->codec_id = AV_CODEC_ID_MPEG1VIDEO; + st->need_parsing = AVSTREAM_PARSE_HEADERS; //get keyframe flag etc. + break; + case 9: + st->codec->codec_type = AVMEDIA_TYPE_AUDIO; + st->codec->codec_id = AV_CODEC_ID_PCM_S24LE; + st->codec->channels = 1; + st->codec->channel_layout = AV_CH_LAYOUT_MONO; + st->codec->sample_rate = 48000; + st->codec->bit_rate = 3 * 1 * 48000 * 8; + st->codec->block_align = 3 * 1; + st->codec->bits_per_coded_sample = 24; + break; + case 10: + st->codec->codec_type = AVMEDIA_TYPE_AUDIO; + st->codec->codec_id = AV_CODEC_ID_PCM_S16LE; + st->codec->channels = 1; + st->codec->channel_layout = AV_CH_LAYOUT_MONO; + st->codec->sample_rate = 48000; + st->codec->bit_rate = 2 * 1 * 48000 * 8; + st->codec->block_align = 2 * 1; + st->codec->bits_per_coded_sample = 16; + break; + case 17: + st->codec->codec_type = AVMEDIA_TYPE_AUDIO; + st->codec->codec_id = AV_CODEC_ID_AC3; + st->codec->channels = 2; + st->codec->channel_layout = AV_CH_LAYOUT_STEREO; + st->codec->sample_rate = 48000; + break; + // timecode tracks: + case 7: + case 8: + case 24: + st->codec->codec_type = AVMEDIA_TYPE_DATA; + st->codec->codec_id = AV_CODEC_ID_NONE; + break; + default: + st->codec->codec_type = AVMEDIA_TYPE_UNKNOWN; + st->codec->codec_id = AV_CODEC_ID_NONE; + break; + } + return s->nb_streams - 1; +} + +/** + * @brief filters out interesting tags from material information. + * @param len length of tag section, will be adjusted to contain remaining bytes + * @param si struct to store collected information into + */ +static void gxf_material_tags(AVIOContext *pb, int *len, struct gxf_stream_info *si) { + si->first_field = AV_NOPTS_VALUE; + si->last_field = AV_NOPTS_VALUE; + while (*len >= 2) { + GXFMatTag tag = avio_r8(pb); + int tlen = avio_r8(pb); + *len -= 2; + if (tlen > *len) + return; + *len -= tlen; + if (tlen == 4) { + uint32_t value = avio_rb32(pb); + if (tag == MAT_FIRST_FIELD) + si->first_field = value; + else if (tag == MAT_LAST_FIELD) + si->last_field = value; + } else + avio_skip(pb, tlen); + } +} + +static const AVRational frame_rate_tab[] = { + { 60, 1}, + {60000, 1001}, + { 50, 1}, + { 30, 1}, + {30000, 1001}, + { 25, 1}, + { 24, 1}, + {24000, 1001}, + { 0, 0}, +}; + +/** + * @brief convert fps tag value to AVRational fps + * @param fps fps value from tag + * @return fps as AVRational, or 0 / 0 if unknown + */ +static AVRational fps_tag2avr(int32_t fps) { + if (fps < 1 || fps > 9) fps = 9; + return frame_rate_tab[fps - 1]; +} + +/** + * @brief convert UMF attributes flags to AVRational fps + * @param flags UMF flags to convert + * @return fps as AVRational, or 0 / 0 if unknown + */ +static AVRational fps_umf2avr(uint32_t flags) { + static const AVRational map[] = {{50, 1}, {60000, 1001}, {24, 1}, + {25, 1}, {30000, 1001}}; + int idx = av_log2((flags & 0x7c0) >> 6); + return map[idx]; +} + +/** + * @brief filters out interesting tags from track information. + * @param len length of tag section, will be adjusted to contain remaining bytes + * @param si struct to store collected information into + */ +static void gxf_track_tags(AVIOContext *pb, int *len, struct gxf_stream_info *si) { + si->frames_per_second = (AVRational){0, 0}; + si->fields_per_frame = 0; + si->track_aux_data = 0x80000000; + while (*len >= 2) { + GXFTrackTag tag = avio_r8(pb); + int tlen = avio_r8(pb); + *len -= 2; + if (tlen > *len) + return; + *len -= tlen; + if (tlen == 4) { + uint32_t value = avio_rb32(pb); + if (tag == TRACK_FPS) + si->frames_per_second = fps_tag2avr(value); + else if (tag == TRACK_FPF && (value == 1 || value == 2)) + si->fields_per_frame = value; + } else if (tlen == 8 && tag == TRACK_AUX) + si->track_aux_data = avio_rl64(pb); + else + avio_skip(pb, tlen); + } +} + +/** + * @brief read index from FLT packet into stream 0 av_index + */ +static void gxf_read_index(AVFormatContext *s, int pkt_len) { + AVIOContext *pb = s->pb; + AVStream *st; + uint32_t fields_per_map = avio_rl32(pb); + uint32_t map_cnt = avio_rl32(pb); + int i; + pkt_len -= 8; + if ((s->flags & AVFMT_FLAG_IGNIDX) || !s->streams) { + avio_skip(pb, pkt_len); + return; + } + st = s->streams[0]; + if (map_cnt > 1000) { + av_log(s, AV_LOG_ERROR, "too many index entries %u (%x)\n", map_cnt, map_cnt); + map_cnt = 1000; + } + if (pkt_len < 4 * map_cnt) { + av_log(s, AV_LOG_ERROR, "invalid index length\n"); + avio_skip(pb, pkt_len); + return; + } + pkt_len -= 4 * map_cnt; + av_add_index_entry(st, 0, 0, 0, 0, 0); + for (i = 0; i < map_cnt; i++) + av_add_index_entry(st, (uint64_t)avio_rl32(pb) * 1024, + i * (uint64_t)fields_per_map + 1, 0, 0, 0); + avio_skip(pb, pkt_len); +} + +static int gxf_header(AVFormatContext *s) { + AVIOContext *pb = s->pb; + GXFPktType pkt_type; + int map_len; + int len; + AVRational main_timebase = {0, 0}; + struct gxf_stream_info *si = s->priv_data; + int i; + if (!parse_packet_header(pb, &pkt_type, &map_len) || pkt_type != PKT_MAP) { + av_log(s, AV_LOG_ERROR, "map packet not found\n"); + return 0; + } + map_len -= 2; + if (avio_r8(pb) != 0x0e0 || avio_r8(pb) != 0xff) { + av_log(s, AV_LOG_ERROR, "unknown version or invalid map preamble\n"); + return 0; + } + map_len -= 2; + len = avio_rb16(pb); // length of material data section + if (len > map_len) { + av_log(s, AV_LOG_ERROR, "material data longer than map data\n"); + return 0; + } + map_len -= len; + gxf_material_tags(pb, &len, si); + avio_skip(pb, len); + map_len -= 2; + len = avio_rb16(pb); // length of track description + if (len > map_len) { + av_log(s, AV_LOG_ERROR, "track description longer than map data\n"); + return 0; + } + map_len -= len; + while (len > 0) { + int track_type, track_id, track_len; + AVStream *st; + int idx; + len -= 4; + track_type = avio_r8(pb); + track_id = avio_r8(pb); + track_len = avio_rb16(pb); + len -= track_len; + if (!(track_type & 0x80)) { + av_log(s, AV_LOG_ERROR, "invalid track type %x\n", track_type); + continue; + } + track_type &= 0x7f; + if ((track_id & 0xc0) != 0xc0) { + av_log(s, AV_LOG_ERROR, "invalid track id %x\n", track_id); + continue; + } + track_id &= 0x3f; + gxf_track_tags(pb, &track_len, si); + // check for timecode tracks + if (track_type == 7 || track_type == 8 || track_type == 24) { + add_timecode_metadata(&s->metadata, "timecode", + si->track_aux_data & 0xffffffff, + si->fields_per_frame); + + } + avio_skip(pb, track_len); + + idx = get_sindex(s, track_id, track_type); + if (idx < 0) continue; + st = s->streams[idx]; + if (!main_timebase.num || !main_timebase.den) { + main_timebase.num = si->frames_per_second.den; + main_timebase.den = si->frames_per_second.num * 2; + } + st->start_time = si->first_field; + if (si->first_field != AV_NOPTS_VALUE && si->last_field != AV_NOPTS_VALUE) + st->duration = si->last_field - si->first_field; + } + if (len < 0) + av_log(s, AV_LOG_ERROR, "invalid track description length specified\n"); + if (map_len) + avio_skip(pb, map_len); + if (!parse_packet_header(pb, &pkt_type, &len)) { + av_log(s, AV_LOG_ERROR, "sync lost in header\n"); + return -1; + } + if (pkt_type == PKT_FLT) { + gxf_read_index(s, len); + if (!parse_packet_header(pb, &pkt_type, &len)) { + av_log(s, AV_LOG_ERROR, "sync lost in header\n"); + return -1; + } + } + if (pkt_type == PKT_UMF) { + if (len >= 0x39) { + AVRational fps; + len -= 0x39; + avio_skip(pb, 5); // preamble + avio_skip(pb, 0x30); // payload description + fps = fps_umf2avr(avio_rl32(pb)); + if (!main_timebase.num || !main_timebase.den) { + av_log(s, AV_LOG_WARNING, "No FPS track tag, using UMF fps tag." + " This might give wrong results.\n"); + // this may not always be correct, but simply the best we can get + main_timebase.num = fps.den; + main_timebase.den = fps.num * 2; + } + + if (len >= 0x18) { + len -= 0x18; + avio_skip(pb, 0x10); + add_timecode_metadata(&s->metadata, "timecode_at_mark_in", + avio_rl32(pb), si->fields_per_frame); + add_timecode_metadata(&s->metadata, "timecode_at_mark_out", + avio_rl32(pb), si->fields_per_frame); + } + } else + av_log(s, AV_LOG_INFO, "UMF packet too short\n"); + } else + av_log(s, AV_LOG_INFO, "UMF packet missing\n"); + avio_skip(pb, len); + // set a fallback value, 60000/1001 is specified for audio-only files + // so use that regardless of why we do not know the video frame rate. + if (!main_timebase.num || !main_timebase.den) + main_timebase = (AVRational){1001, 60000}; + for (i = 0; i < s->nb_streams; i++) { + AVStream *st = s->streams[i]; + avpriv_set_pts_info(st, 32, main_timebase.num, main_timebase.den); + } + return 0; +} + +#define READ_ONE() \ + { \ + if (!max_interval-- || url_feof(pb)) \ + goto out; \ + tmp = tmp << 8 | avio_r8(pb); \ + } + +/** + * @brief resync the stream on the next media packet with specified properties + * @param max_interval how many bytes to search for matching packet at most + * @param track track id the media packet must belong to, -1 for any + * @param timestamp minimum timestamp (== field number) the packet must have, -1 for any + * @return timestamp of packet found + */ +static int64_t gxf_resync_media(AVFormatContext *s, uint64_t max_interval, int track, int timestamp) { + uint32_t tmp; + uint64_t last_pos; + uint64_t last_found_pos = 0; + int cur_track; + int64_t cur_timestamp = AV_NOPTS_VALUE; + int len; + AVIOContext *pb = s->pb; + GXFPktType type; + tmp = avio_rb32(pb); +start: + while (tmp) + READ_ONE(); + READ_ONE(); + if (tmp != 1) + goto start; + last_pos = avio_tell(pb); + if (avio_seek(pb, -5, SEEK_CUR) < 0) + goto out; + if (!parse_packet_header(pb, &type, &len) || type != PKT_MEDIA) { + if (avio_seek(pb, last_pos, SEEK_SET) < 0) + goto out; + goto start; + } + avio_r8(pb); + cur_track = avio_r8(pb); + cur_timestamp = avio_rb32(pb); + last_found_pos = avio_tell(pb) - 16 - 6; + if ((track >= 0 && track != cur_track) || (timestamp >= 0 && timestamp > cur_timestamp)) { + if (avio_seek(pb, last_pos, SEEK_SET) >= 0) + goto start; + } +out: + if (last_found_pos) + avio_seek(pb, last_found_pos, SEEK_SET); + return cur_timestamp; +} + +static int gxf_packet(AVFormatContext *s, AVPacket *pkt) { + AVIOContext *pb = s->pb; + GXFPktType pkt_type; + int pkt_len; + struct gxf_stream_info *si = s->priv_data; + + while (!pb->eof_reached) { + AVStream *st; + int track_type, track_id, ret; + int field_nr, field_info, skip = 0; + int stream_index; + if (!parse_packet_header(pb, &pkt_type, &pkt_len)) { + if (!url_feof(pb)) + av_log(s, AV_LOG_ERROR, "sync lost\n"); + return -1; + } + if (pkt_type == PKT_FLT) { + gxf_read_index(s, pkt_len); + continue; + } + if (pkt_type != PKT_MEDIA) { + avio_skip(pb, pkt_len); + continue; + } + if (pkt_len < 16) { + av_log(s, AV_LOG_ERROR, "invalid media packet length\n"); + continue; + } + pkt_len -= 16; + track_type = avio_r8(pb); + track_id = avio_r8(pb); + stream_index = get_sindex(s, track_id, track_type); + if (stream_index < 0) + return stream_index; + st = s->streams[stream_index]; + field_nr = avio_rb32(pb); + field_info = avio_rb32(pb); + avio_rb32(pb); // "timeline" field number + avio_r8(pb); // flags + avio_r8(pb); // reserved + if (st->codec->codec_id == AV_CODEC_ID_PCM_S24LE || + st->codec->codec_id == AV_CODEC_ID_PCM_S16LE) { + int first = field_info >> 16; + int last = field_info & 0xffff; // last is exclusive + int bps = av_get_bits_per_sample(st->codec->codec_id)>>3; + if (first <= last && last*bps <= pkt_len) { + avio_skip(pb, first*bps); + skip = pkt_len - last*bps; + pkt_len = (last-first)*bps; + } else + av_log(s, AV_LOG_ERROR, "invalid first and last sample values\n"); + } + ret = av_get_packet(pb, pkt, pkt_len); + if (skip) + avio_skip(pb, skip); + pkt->stream_index = stream_index; + pkt->dts = field_nr; + + //set duration manually for DV or else lavf misdetects the frame rate + if (st->codec->codec_id == AV_CODEC_ID_DVVIDEO) + pkt->duration = si->fields_per_frame; + + return ret; + } + return AVERROR_EOF; +} + +static int gxf_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags) { + int res = 0; + uint64_t pos; + uint64_t maxlen = 100 * 1024 * 1024; + AVStream *st = s->streams[0]; + int64_t start_time = s->streams[stream_index]->start_time; + int64_t found; + int idx; + if (timestamp < start_time) timestamp = start_time; + idx = av_index_search_timestamp(st, timestamp - start_time, + AVSEEK_FLAG_ANY | AVSEEK_FLAG_BACKWARD); + if (idx < 0) + return -1; + pos = st->index_entries[idx].pos; + if (idx < st->nb_index_entries - 2) + maxlen = st->index_entries[idx + 2].pos - pos; + maxlen = FFMAX(maxlen, 200 * 1024); + res = avio_seek(s->pb, pos, SEEK_SET); + if (res < 0) + return res; + found = gxf_resync_media(s, maxlen, -1, timestamp); + if (FFABS(found - timestamp) > 4) + return -1; + return 0; +} + +static int64_t gxf_read_timestamp(AVFormatContext *s, int stream_index, + int64_t *pos, int64_t pos_limit) { + AVIOContext *pb = s->pb; + int64_t res; + if (avio_seek(pb, *pos, SEEK_SET) < 0) + return AV_NOPTS_VALUE; + res = gxf_resync_media(s, pos_limit - *pos, -1, -1); + *pos = avio_tell(pb); + return res; +} + +AVInputFormat ff_gxf_demuxer = { + .name = "gxf", + .long_name = NULL_IF_CONFIG_SMALL("GXF (General eXchange Format)"), + .priv_data_size = sizeof(struct gxf_stream_info), + .read_probe = gxf_probe, + .read_header = gxf_header, + .read_packet = gxf_packet, + .read_seek = gxf_seek, + .read_timestamp = gxf_read_timestamp, +}; 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