609 lines
20 KiB
C
Executable File
609 lines
20 KiB
C
Executable File
/*
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* GXF demuxer.
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* Copyright (c) 2006 Reimar Doeffinger
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*
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* This file is part of FFmpeg.
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*
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* FFmpeg is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* FFmpeg is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with FFmpeg; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include <inttypes.h>
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#include "libavutil/channel_layout.h"
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#include "libavutil/common.h"
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#include "avformat.h"
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#include "internal.h"
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#include "gxf.h"
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#include "libavcodec/mpeg12data.h"
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struct gxf_stream_info {
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int64_t first_field;
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int64_t last_field;
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AVRational frames_per_second;
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int32_t fields_per_frame;
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int64_t track_aux_data;
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};
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/**
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* @brief parse gxf timecode and add it to metadata
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*/
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static int add_timecode_metadata(AVDictionary **pm, const char *key, uint32_t timecode, int fields_per_frame)
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{
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char tmp[128];
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int field = timecode & 0xff;
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int frame = fields_per_frame ? field / fields_per_frame : field;
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int second = (timecode >> 8) & 0xff;
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int minute = (timecode >> 16) & 0xff;
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int hour = (timecode >> 24) & 0x1f;
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int drop = (timecode >> 29) & 1;
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// bit 30: color_frame, unused
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// ignore invalid time code
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if (timecode >> 31)
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return 0;
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snprintf(tmp, sizeof(tmp), "%02d:%02d:%02d%c%02d",
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hour, minute, second, drop ? ';' : ':', frame);
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return av_dict_set(pm, key, tmp, 0);
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}
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/**
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* @brief parses a packet header, extracting type and length
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* @param pb AVIOContext to read header from
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* @param type detected packet type is stored here
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* @param length detected packet length, excluding header is stored here
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* @return 0 if header not found or contains invalid data, 1 otherwise
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*/
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static int parse_packet_header(AVIOContext *pb, GXFPktType *type, int *length) {
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if (avio_rb32(pb))
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return 0;
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if (avio_r8(pb) != 1)
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return 0;
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*type = avio_r8(pb);
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*length = avio_rb32(pb);
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if ((*length >> 24) || *length < 16)
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return 0;
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*length -= 16;
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if (avio_rb32(pb))
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return 0;
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if (avio_r8(pb) != 0xe1)
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return 0;
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if (avio_r8(pb) != 0xe2)
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return 0;
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return 1;
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}
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/**
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* @brief check if file starts with a PKT_MAP header
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*/
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static int gxf_probe(const AVProbeData *p) {
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static const uint8_t startcode[] = {0, 0, 0, 0, 1, 0xbc}; // start with map packet
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static const uint8_t endcode[] = {0, 0, 0, 0, 0xe1, 0xe2};
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if (!memcmp(p->buf, startcode, sizeof(startcode)) &&
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!memcmp(&p->buf[16 - sizeof(endcode)], endcode, sizeof(endcode)))
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return AVPROBE_SCORE_MAX;
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return 0;
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}
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/**
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* @brief gets the stream index for the track with the specified id, creates new
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* stream if not found
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* @param id id of stream to find / add
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* @param format stream format identifier
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*/
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static int get_sindex(AVFormatContext *s, int id, int format) {
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int i;
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AVStream *st = NULL;
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i = ff_find_stream_index(s, id);
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if (i >= 0)
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return i;
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st = avformat_new_stream(s, NULL);
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if (!st)
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return AVERROR(ENOMEM);
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st->id = id;
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switch (format) {
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case 3:
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case 4:
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st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
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st->codecpar->codec_id = AV_CODEC_ID_MJPEG;
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break;
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case 13:
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case 14:
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case 15:
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case 16:
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case 25:
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st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
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st->codecpar->codec_id = AV_CODEC_ID_DVVIDEO;
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break;
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case 11:
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case 12:
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case 20:
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st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
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st->codecpar->codec_id = AV_CODEC_ID_MPEG2VIDEO;
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st->need_parsing = AVSTREAM_PARSE_HEADERS; //get keyframe flag etc.
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break;
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case 22:
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case 23:
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st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
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st->codecpar->codec_id = AV_CODEC_ID_MPEG1VIDEO;
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st->need_parsing = AVSTREAM_PARSE_HEADERS; //get keyframe flag etc.
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break;
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case 9:
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st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
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st->codecpar->codec_id = AV_CODEC_ID_PCM_S24LE;
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st->codecpar->channels = 1;
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st->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
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st->codecpar->sample_rate = 48000;
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st->codecpar->bit_rate = 3 * 1 * 48000 * 8;
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st->codecpar->block_align = 3 * 1;
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st->codecpar->bits_per_coded_sample = 24;
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break;
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case 10:
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st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
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st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE;
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st->codecpar->channels = 1;
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st->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
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st->codecpar->sample_rate = 48000;
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st->codecpar->bit_rate = 2 * 1 * 48000 * 8;
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st->codecpar->block_align = 2 * 1;
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st->codecpar->bits_per_coded_sample = 16;
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break;
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case 17:
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st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
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st->codecpar->codec_id = AV_CODEC_ID_AC3;
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st->codecpar->channels = 2;
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st->codecpar->channel_layout = AV_CH_LAYOUT_STEREO;
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st->codecpar->sample_rate = 48000;
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break;
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case 26: /* AVCi50 / AVCi100 (AVC Intra) */
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case 29: /* AVCHD */
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st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
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st->codecpar->codec_id = AV_CODEC_ID_H264;
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st->need_parsing = AVSTREAM_PARSE_HEADERS;
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break;
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// timecode tracks:
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case 7:
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case 8:
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case 24:
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st->codecpar->codec_type = AVMEDIA_TYPE_DATA;
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st->codecpar->codec_id = AV_CODEC_ID_NONE;
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break;
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case 30:
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st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
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st->codecpar->codec_id = AV_CODEC_ID_DNXHD;
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break;
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default:
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st->codecpar->codec_type = AVMEDIA_TYPE_UNKNOWN;
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st->codecpar->codec_id = AV_CODEC_ID_NONE;
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break;
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}
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return s->nb_streams - 1;
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}
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/**
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* @brief filters out interesting tags from material information.
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* @param len length of tag section, will be adjusted to contain remaining bytes
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* @param si struct to store collected information into
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*/
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static void gxf_material_tags(AVIOContext *pb, int *len, struct gxf_stream_info *si) {
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si->first_field = AV_NOPTS_VALUE;
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si->last_field = AV_NOPTS_VALUE;
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while (*len >= 2) {
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GXFMatTag tag = avio_r8(pb);
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int tlen = avio_r8(pb);
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*len -= 2;
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if (tlen > *len)
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return;
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*len -= tlen;
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if (tlen == 4) {
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uint32_t value = avio_rb32(pb);
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if (tag == MAT_FIRST_FIELD)
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si->first_field = value;
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else if (tag == MAT_LAST_FIELD)
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si->last_field = value;
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} else
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avio_skip(pb, tlen);
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}
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}
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static const AVRational frame_rate_tab[] = {
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{ 60, 1},
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{60000, 1001},
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{ 50, 1},
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{ 30, 1},
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{30000, 1001},
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{ 25, 1},
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{ 24, 1},
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{24000, 1001},
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{ 0, 0},
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};
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/**
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* @brief convert fps tag value to AVRational fps
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* @param fps fps value from tag
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* @return fps as AVRational, or 0 / 0 if unknown
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*/
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static AVRational fps_tag2avr(int32_t fps) {
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if (fps < 1 || fps > 9) fps = 9;
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return frame_rate_tab[fps - 1];
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}
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/**
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* @brief convert UMF attributes flags to AVRational fps
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* @param flags UMF flags to convert
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* @return fps as AVRational, or 0 / 0 if unknown
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*/
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static AVRational fps_umf2avr(uint32_t flags) {
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static const AVRational map[] = {{50, 1}, {60000, 1001}, {24, 1},
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{25, 1}, {30000, 1001}};
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int idx = av_log2((flags & 0x7c0) >> 6);
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return map[idx];
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}
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/**
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* @brief filters out interesting tags from track information.
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* @param len length of tag section, will be adjusted to contain remaining bytes
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* @param si struct to store collected information into
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*/
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static void gxf_track_tags(AVIOContext *pb, int *len, struct gxf_stream_info *si) {
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si->frames_per_second = (AVRational){0, 0};
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si->fields_per_frame = 0;
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si->track_aux_data = 0x80000000;
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while (*len >= 2) {
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GXFTrackTag tag = avio_r8(pb);
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int tlen = avio_r8(pb);
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*len -= 2;
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if (tlen > *len)
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return;
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*len -= tlen;
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if (tlen == 4) {
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uint32_t value = avio_rb32(pb);
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if (tag == TRACK_FPS)
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si->frames_per_second = fps_tag2avr(value);
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else if (tag == TRACK_FPF && (value == 1 || value == 2))
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si->fields_per_frame = value;
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} else if (tlen == 8 && tag == TRACK_AUX)
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si->track_aux_data = avio_rl64(pb);
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else
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avio_skip(pb, tlen);
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}
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}
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/**
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* @brief read index from FLT packet into stream 0 av_index
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*/
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static void gxf_read_index(AVFormatContext *s, int pkt_len) {
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AVIOContext *pb = s->pb;
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AVStream *st;
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uint32_t fields_per_map = avio_rl32(pb);
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uint32_t map_cnt = avio_rl32(pb);
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int i;
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pkt_len -= 8;
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if ((s->flags & AVFMT_FLAG_IGNIDX) || !s->streams) {
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avio_skip(pb, pkt_len);
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return;
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}
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st = s->streams[0];
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if (map_cnt > 1000) {
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av_log(s, AV_LOG_ERROR,
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"too many index entries %"PRIu32" (%"PRIx32")\n",
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map_cnt, map_cnt);
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map_cnt = 1000;
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}
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if (pkt_len < 4 * map_cnt) {
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av_log(s, AV_LOG_ERROR, "invalid index length\n");
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avio_skip(pb, pkt_len);
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return;
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}
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pkt_len -= 4 * map_cnt;
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av_add_index_entry(st, 0, 0, 0, 0, 0);
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for (i = 0; i < map_cnt; i++)
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av_add_index_entry(st, (uint64_t)avio_rl32(pb) * 1024,
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i * (uint64_t)fields_per_map + 1, 0, 0, 0);
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avio_skip(pb, pkt_len);
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}
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static int gxf_header(AVFormatContext *s) {
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AVIOContext *pb = s->pb;
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GXFPktType pkt_type;
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int map_len;
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int len;
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AVRational main_timebase = {0, 0};
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struct gxf_stream_info *si = s->priv_data;
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int i;
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if (!parse_packet_header(pb, &pkt_type, &map_len) || pkt_type != PKT_MAP) {
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av_log(s, AV_LOG_ERROR, "map packet not found\n");
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return 0;
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}
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map_len -= 2;
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if (avio_r8(pb) != 0x0e0 || avio_r8(pb) != 0xff) {
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av_log(s, AV_LOG_ERROR, "unknown version or invalid map preamble\n");
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return 0;
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}
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map_len -= 2;
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len = avio_rb16(pb); // length of material data section
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if (len > map_len) {
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av_log(s, AV_LOG_ERROR, "material data longer than map data\n");
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return 0;
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}
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map_len -= len;
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gxf_material_tags(pb, &len, si);
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avio_skip(pb, len);
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map_len -= 2;
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len = avio_rb16(pb); // length of track description
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if (len > map_len) {
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av_log(s, AV_LOG_ERROR, "track description longer than map data\n");
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return 0;
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}
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map_len -= len;
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while (len > 0) {
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int track_type, track_id, track_len;
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AVStream *st;
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int idx;
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len -= 4;
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track_type = avio_r8(pb);
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track_id = avio_r8(pb);
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track_len = avio_rb16(pb);
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len -= track_len;
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if (!(track_type & 0x80)) {
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av_log(s, AV_LOG_ERROR, "invalid track type %x\n", track_type);
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continue;
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}
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track_type &= 0x7f;
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if ((track_id & 0xc0) != 0xc0) {
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av_log(s, AV_LOG_ERROR, "invalid track id %x\n", track_id);
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continue;
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}
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track_id &= 0x3f;
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gxf_track_tags(pb, &track_len, si);
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// check for timecode tracks
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if (track_type == 7 || track_type == 8 || track_type == 24) {
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add_timecode_metadata(&s->metadata, "timecode",
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si->track_aux_data & 0xffffffff,
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si->fields_per_frame);
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}
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avio_skip(pb, track_len);
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idx = get_sindex(s, track_id, track_type);
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if (idx < 0) continue;
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st = s->streams[idx];
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if (!main_timebase.num || !main_timebase.den) {
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main_timebase.num = si->frames_per_second.den;
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main_timebase.den = si->frames_per_second.num * 2;
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}
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st->start_time = si->first_field;
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if (si->first_field != AV_NOPTS_VALUE && si->last_field != AV_NOPTS_VALUE)
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st->duration = si->last_field - si->first_field;
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}
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if (len < 0)
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av_log(s, AV_LOG_ERROR, "invalid track description length specified\n");
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if (map_len)
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avio_skip(pb, map_len);
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if (!parse_packet_header(pb, &pkt_type, &len)) {
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av_log(s, AV_LOG_ERROR, "sync lost in header\n");
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return -1;
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}
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if (pkt_type == PKT_FLT) {
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gxf_read_index(s, len);
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if (!parse_packet_header(pb, &pkt_type, &len)) {
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av_log(s, AV_LOG_ERROR, "sync lost in header\n");
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return -1;
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}
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}
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if (pkt_type == PKT_UMF) {
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if (len >= 0x39) {
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AVRational fps;
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len -= 0x39;
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avio_skip(pb, 5); // preamble
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avio_skip(pb, 0x30); // payload description
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fps = fps_umf2avr(avio_rl32(pb));
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if (!main_timebase.num || !main_timebase.den) {
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av_log(s, AV_LOG_WARNING, "No FPS track tag, using UMF fps tag."
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" This might give wrong results.\n");
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// this may not always be correct, but simply the best we can get
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main_timebase.num = fps.den;
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main_timebase.den = fps.num * 2;
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}
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if (len >= 0x18) {
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len -= 0x18;
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avio_skip(pb, 0x10);
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add_timecode_metadata(&s->metadata, "timecode_at_mark_in",
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avio_rl32(pb), si->fields_per_frame);
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add_timecode_metadata(&s->metadata, "timecode_at_mark_out",
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avio_rl32(pb), si->fields_per_frame);
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}
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} else
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av_log(s, AV_LOG_INFO, "UMF packet too short\n");
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} else
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av_log(s, AV_LOG_INFO, "UMF packet missing\n");
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avio_skip(pb, len);
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// set a fallback value, 60000/1001 is specified for audio-only files
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// so use that regardless of why we do not know the video frame rate.
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if (!main_timebase.num || !main_timebase.den)
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main_timebase = (AVRational){1001, 60000};
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for (i = 0; i < s->nb_streams; i++) {
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AVStream *st = s->streams[i];
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avpriv_set_pts_info(st, 32, main_timebase.num, main_timebase.den);
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}
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return 0;
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}
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#define READ_ONE() \
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{ \
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if (!max_interval-- || avio_feof(pb)) \
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goto out; \
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tmp = tmp << 8 | avio_r8(pb); \
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}
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/**
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* @brief resync the stream on the next media packet with specified properties
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* @param max_interval how many bytes to search for matching packet at most
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* @param track track id the media packet must belong to, -1 for any
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* @param timestamp minimum timestamp (== field number) the packet must have, -1 for any
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* @return timestamp of packet found
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*/
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static int64_t gxf_resync_media(AVFormatContext *s, uint64_t max_interval, int track, int timestamp) {
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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 (!avio_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->codecpar->codec_id == AV_CODEC_ID_PCM_S24LE ||
|
|
st->codecpar->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->codecpar->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->codecpar->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) {
|
|
int64_t 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,
|
|
};
|