Den 30.05.2025 00:15, skrev Andrew Randrianasulu:

пт, 30 мая 2025 г., 00:30 Andrew Randrianasulu <randrianasulu@gmail.com>:

чт, 29 мая 2025 г., 23:42 Terje J. Hanssen via Cin <cin@lists.cinelerra-gg.org>:

Is it possible with CinGG's Record utility (via FFMPEG) to record a stream to file segments of same duration or file size and use auto-naming?

Typical example:
Record a video/audio input stream (i.e from playing a camcorder tape cassette) and encode to output file segments of 10 minutes or 10 GB each and auto-name file numbers.

Similar example code using an input file instead at
https://unix.stackexchange.com/questions/1670/how-can-i-use-ffmpeg-to-split-mpeg-video-into-10-minute-chunks

Just use what is built into ffmpeg to do exactly this.

ffmpeg -i invid.mp4 -threads 3 \
       -vcodec copy -f segment -segment_time 10:00 \
       -reset_timestamps 1 \
       cam_out_h264_%02d.mp4

This will split it into roughly 10-minute chunks, split at the relevant keyframes, and will output to the files cam_out_h264_01.mp4, cam_out_h264_02.mp4, etc.

Very interesting question! Never tried this, did not even know it existed!

As long as this -f just ordinary avformat muxer you probably can copy your favourite ffmpeg video/audio profiles with new .seg name and put "segmented" at very first line there , where "mov" or "matroska" or other format name was, and add rest of options. And add pattern (%02d) into name just as with ffmpeg-based image lists.

I'll try this with termux's version, but I do not have audio here so it will be incomplete.

so I created this file:

cat ffmpeg/video/mpeg2.seg

segment mpeg2video

segment_format=mpeg

segment_time=00:10

reset_timestamps=1

trellis=2

mbd=rd

cmp=2

subcmp=2

b=4000000

and it worked! in sense it created six segments, each with corresponding increasing timecode. But they all uneven duration, probably due to mpeg2 codec placing keyframes at will.

You can try to modify it back to 10:00 segment time and see how it work for longer encode?

As I'm not sure if and how you applied your file above with regards to Cingg Record,

I simply did a test with my system's ffmpeg segment muxer:
https://ffmpeg.org/ffmpeg-formats.html#segment_002c-stream_005fsegment_002c-ssegment

Input file: hdv09_04_h264.mp4
  Duration: 00:03:58.88, start: 0.000000, bitrate: 8963 kb/s

Tried 1 minute segment time:

ffmpeg -hide_banner -i hdv09_04_h264.mp4 -threads 3 \
       -vcodec copy -f segment -segment_time 01:00 \
       -reset_timestamps 1 \
       cam_out_h264_%02d.mp4

[segment @ 0x563c2874fa80] Opening 'cam_out_h264_01.mp4' for writingeed=52.1x    
[segment @ 0x563c2874fa80] Opening 'cam_out_h264_02.mp4' for writingeed=55.5x    
[segment @ 0x563c2874fa80] Opening 'cam_out_h264_03.mp4' for writingeed=  57x    
[out#0/segment @ 0x563c28727680] video:257421KiB audio:3749KiB subtitle:0KiB other streams:0KiB global headers:0KiB muxing overhead: unknown
frame= 5972 fps=1445 q=-1.0 Lsize=N/A time=00:03:58.80 bitrate=N/A speed=57.8x    
[aac @ 0x563c28721a40] Qavg: 454.522

68M    cam_out_h264_00.mp4
63M    cam_out_h264_01.mp4
59M    cam_out_h264_02.mp4
68M    cam_out_h264_03.mp4
--------

  Duration: 00:01:00.38, start: 0.058000, bitrate: 9394 kb/s
  Duration: 00:01:00.00, start: 0.000000, bitrate: 8672 kb/s
  Duration: 00:01:00.60, start: 0.000000, bitrate: 8104 kb/s
  Duration: 00:00:57.93, start: 0.000000, bitrate: 9705 kb/s
 
In total:     00:03:58.93  which is 00:00:00.03 (=3/100 sek) more than the input file
which I think is good enough for practical purposes (editing and backup/preservation/archival)

I wonder if it is within or out of our reach to make some targeted profiles for backup/preservation?
I.e would it be of interest and possible to utilize/integrate/use oss tools and scripts as found here:
https://avpres.net/Bash_AVpres/
https://avpres.net/FFmpeg/im_FFV1.html

The programs dvgrab and possibly the newer vrecord can also autosplit by scenes
https://linux.die.net/man/1/dvgrab
https://github.com/amiaopensource/vrecord
https://github.com/mipops/dvrescue