Den 17.09.2024 14:11, skrev Stefan de Konink via Cin:

There are quite some topics online mentioning the when MTS files (exceeding 2GB) are naively added to a timeline. The problem that then appears is that the audio is typically "shorter" than the video, and it does not appear in the interface. Cinelerra will even shift the audio track under the previous track.

It is mentioned that Adobe Premiere is able to parse an AVCHD structure, including the ability to use meta information such as timecode, which is not available from MTS files directly.

Other workarounds that are mentioned to first join the MTS files. FFmpeg has the option concat demuxer and concat protocol. But it pulls another surprise...

Have you tried simple "cat" to join clips in a Linux terminal?

I have not tested this with MTS files, but it works for my HDV.m2t files (mpeg2 video/mp2 audio)

    cat file1 file2 > file1+2

file1+2 may load directly in Cingg if the clips were continuously auto-clipped.

For random clips, there might arise a black segment between the clips.

In my experience this is possible to cleanup first with

    fmpeg -hide_banner -i file1+2 -reset_timestamps 1 -c copy file1+2_cleanup 


ffmpeg or ffprobe may still complain about single "Packet corrupt" or "timestamp discontinuity", which I simply have ignored.

ffmpeg -i "concat:00152.MTS|00153.MTS|00154.MTS" -vcodec copy -acodec copy test.ts
ffmpeg version n7.0.1 Copyright (c) 2000-2024 the FFmpeg developers
  built with gcc 14.1.1 (GCC) 20240522
  configuration: --prefix=/usr --disable-debug --disable-static --disable-stripping --enable-amf --enable-avisynth --enable-cuda-llvm --enable-lto --enable-fontconfig --enable-frei0r --enable-gmp --enable-gpl --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libdav1d --enable-libdrm --enable-libdvdnav --enable-libdvdread --enable-libfreetype --enable-libfribidi --enable-libgsm --enable-libharfbuzz --enable-libiec61883 --enable-libjack --enable-libjxl --enable-libmodplug --enable-libmp3lame --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libplacebo --enable-libpulse --enable-librav1e --enable-librsvg --enable-librubberband --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libssh --enable-libsvtav1 --enable-libtheora --enable-libv4l2 --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvpl --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxcb --enable-libxml2 --enable-libxvid --enable-libzimg --enable-mbedtls --enable-nvdec --enable-nvenc --enable-opencl --enable-opengl --enable-shared --enable-vapoursynth --enable-version3 --enable-vulkan
  libavutil      59.  8.100 / 59.  8.100
  libavcodec     61.  3.100 / 61.  3.100
  libavformat    61.  1.100 / 61.  1.100
  libavdevice    61.  1.100 / 61.  1.100
  libavfilter    10.  1.100 / 10.  1.100
  libswscale      8.  1.100 /  8.  1.100
  libswresample   5.  1.100 /  5.  1.100
  libpostproc    58.  1.100 / 58.  1.100
Input #0, mpegts, from 'concat:00152.MTS|00153.MTS|00154.MTS':
  Duration: 00:25:04.36, start: 1.040000, bitrate: 24022 kb/s
  Program 1
  Stream #0:0[0x1011]: Video: h264 (High) (HDMV / 0x564D4448), yuv420p(top first), 1920x1080 [SAR 1:1 DAR 16:9], 25 fps, 25 tbr, 90k tbn
  Stream #0:1[0x1100]: Audio: pcm_bluray (HDMV / 0x564D4448), 48000 Hz, stereo, s16, 1536 kb/s
  Stream #0:2[0x1200]: Subtitle: hdmv_pgs_subtitle (pgssub) ([144][0][0][0] / 0x0090), 1920x1080
File 'test.ts' already exists. Overwrite? [y/N] y
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
  Stream #0:1 -> #0:1 (copy)
Output #0, mpegts, to 'test.ts':
  Metadata:
    encoder         : Lavf61.1.100
  Stream #0:0: Video: h264 (High) (HDMV / 0x564D4448), yuv420p(top first), 1920x1080 [SAR 1:1 DAR 16:9], q=2-31, 25 fps, 25 tbr, 90k tbn
  Stream #0:1: Audio: pcm_bluray (HDMV / 0x564D4448), 48000 Hz, stereo, s16, 1536 kb/s
Press [q] to stop, [?] for help
[mpegts @ 0x600ed54cf540] Stream 1, codec pcm_bluray, is muxed as a private data stream and may not be recognized upon reading.

This results in a video file cinelerra (and others) cannot read.

Instead if we would say do it in pcm_sb16le we would be able to show that the MTS file does contain the audio and FFmpeg is able to read it. I have attached a screenshot showing what happens.

I wonder: could we in Cinelerra implement something that would not open a file as single file or EDL, but instead a concat set of files?

Something in the drop down: "Create a single new resource only". That single resource should be opened via the concat protocol, and then be able as single instance. An EDL, but then at protocol level.

I think this would make sense for many recordings that are split due to filesystem limits, but even for image sequences, if they could be directly opened and edited as if they were single files.