[Cin] Segmented Recording from input stream
Phyllis Smith
phylsmith2017 at gmail.com
Mon Jun 9 18:31:58 CEST 2025
Andrew, I have been contemplating this since you brought it up again with
Terje. Should it be checked into GIT after Terje checks it?
On Sun, Jun 1, 2025 at 1:06 AM Andrew Randrianasulu via Cin <
cin at lists.cinelerra-gg.org> wrote:
> with this patch (git am variety) I can set segment_time in gui, but
> for short test video actual cut time was
> dominated by same set of six keyframes, in my case.
>
> On Sun, Jun 1, 2025 at 4:56 AM Andrew Randrianasulu
> <randrianasulu at gmail.com> wrote:
> >
> >
> >
> > вс, 1 июн. 2025 г., 00:03 Terje J. Hanssen <terjejhanssen at gmail.com>:
> >>
> >>
> >>
> >> On 31.05.2025 05:33, Andrew Randrianasulu wrote:
> >>
> >> On Fri, May 30, 2025 at 4:27 PM Andrew Randrianasulu
> >> <randrianasulu at gmail.com> wrote:
> >>
> >> пт, 30 мая 2025 г., 15:55 Terje J. Hanssen <terjejhanssen at gmail.com>:
> >>
> >> Den 30.05.2025 00:15, skrev Andrew Randrianasulu:
> >>
> >>
> >>
> >> пт, 30 мая 2025 г., 00:30 Andrew Randrianasulu <randrianasulu at gmail.com
> >:
> >>
> >> чт, 29 мая 2025 г., 23:42 Terje J. Hanssen via Cin <
> cin at 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,
> >>
> >> just put file where other video profiles live? (ffmpeg/video folder of
> your cingg installation)
> >>
> >> Attaching test profile trying to utilize segmented muxer for mpeg
> >> system streams
> >>
> >> Put them according to their content into
> >>
> >> /usr/share/cin/ffmpeg/video and /usr/share/cin/ffmpeg/audio for
> >> standard rpm/deb cinelerra install
> >>
> >> make sure they readable by your user (chown -R your_username:users
> >> /usr/share/cin/ffmpeg might fix weird issues like "bad file format")
> >>
> >>
> >> I upgraded to the latest rpm for Leap15.6
> >>
> >> terje at localhost:/usr/share/cin/ffmpeg> ls -lt audio/*.seg audio/seg.*
> video/*.seg video/seg.*
> >> -rw-r--r-- 1 terje users 159 mai 31 17:49 video/mpeg2.seg
> >> -rw-r--r-- 1 terje users 14 mai 31 17:49 video/seg.dfl
> >> -rw-r--r-- 1 terje users 77 mai 31 17:47 audio/mpeg2_mp2.seg
> >> -rw-r--r-- 1 terje users 14 mai 31 17:47 audio/seg.dfl
> >>
> >> In cingg shift-R, select seg from dropdown menu, select both audio and
> >> video encoding (there will be grand total of one choice in each
> >> category),
> >> then put filename like /dev/shm/file%02d.mpeg and try to render
> >>
> >> It will give you files:
> >>
> >>
> >> Loaded a hdv 1080i50 file
> >> Very short segments, maybe just 10 sec each
> >>
> >> root at slax:~# ls -la /dev/shm/seg*
> >> -rw-r--r-- 1 guest users 0 мая 31 06:19 /dev/shm/seg%02d.mpeg
> >> -rw-r--r-- 1 guest users 0 мая 31 05:57 /dev/shm/seg%02d.seg
> >> -rw-r--r-- 1 guest users 2375680 мая 31 06:19 /dev/shm/seg00.mpeg
> >> -rw-r--r-- 1 guest users 1980416 мая 31 06:19 /dev/shm/seg01.mpeg
> >> -rw-r--r-- 1 guest users 1947648 мая 31 06:19 /dev/shm/seg02.mpeg
> >> -rw-r--r-- 1 guest users 2009088 мая 31 06:19 /dev/shm/seg03.mpeg
> >> -rw-r--r-- 1 guest users 2170880 мая 31 06:19 /dev/shm/seg04.mpeg
> >> -rw-r--r-- 1 guest users 2205696 мая 31 06:19 /dev/shm/seg05.mpeg
> >> -rw-r--r-- 1 guest users 2535424 мая 31 06:19 /dev/shm/seg06.mpeg
> >> -rw-r--r-- 1 guest users 1966080 мая 31 06:19 /dev/shm/seg07.mpeg
> >> -rw-r--r-- 1 guest users 1945600 мая 31 06:19 /dev/shm/seg08.mpeg
> >> -rw-r--r-- 1 guest users 2023424 мая 31 06:19 /dev/shm/seg09.mpeg
> >> -rw-r--r-- 1 guest users 2101248 мая 31 06:19 /dev/shm/seg10.mpeg
> >> -rw-r--r-- 1 guest users 1026048 мая 31 06:19 /dev/shm/seg11.mpeg
> >>
> >> Now you can play all fo them gapless with mpv:
> >>
> >>
> >> mpv worked best for audio, though blocking pixels in the video
> >> vlc got dropouts in audio also within a segment
> >>
> >> Tried similar with Shift-P: 1920x1080, 50fps, yuv422 and mpeg2_hq
> profile changed to 50Mbps bitrate, then r (record from v4l2 /dev/video0
> (ms2130)
> >> Got short segments, yuv422 at low bitrate
> >
> >
> >
> > You need to set bitrate explicitly for this profile, I think?
> >
> > in GUI or just add b=16M or what you like.
> >
> > Right now for longer segments you need to modify both profiles manually
> and set segment_time to value you want in both audio and video *.seg
> profiles
> >
> > If it works I think I know where in cingg code I should put override so
> our gui for format (muxer) options will work (right now it stumbles on
> difference between seg and segment )
> >
> >>
> >> root at slax:~# mpv /dev/shm/se*.mpeg
> >> Playing: /dev/shm/seg%02d.mpeg
> >> Failed to recognize file format.
> >> Playing: /dev/shm/seg00.mpeg
> >> (+) Video --vid=1 (mpeg2video 720x576 25.000fps)
> >> (+) Audio --aid=1 (mp2 2ch 48000Hz)
> >> AO: [pulse] 48000Hz stereo 2ch s16
> >> VO: [gpu] 720x576 => 768x576 yuv420p
> >> AV: 00:00:02 / 00:00:02 (97%) A-V: 0.000
> >> Playing: /dev/shm/seg01.mpeg
> >> (+) Video --vid=1 (mpeg2video 720x576 25.000fps)
> >> (+) Audio --aid=1 (mp2 2ch 48000Hz)
> >> AV: 00:00:01 / 00:00:01 (98%) A-V: 0.000
> >> Playing: /dev/shm/seg02.mpeg
> >> (+) Video --vid=1 (mpeg2video 720x576 25.000fps)
> >> (+) Audio --aid=1 (mp2 2ch 48000Hz)
> >> AV: 00:00:01 / 00:00:01 (98%) A-V: 0.000
> >> Playing: /dev/shm/seg03.mpeg
> >> (+) Video --vid=1 (mpeg2video 720x576 25.000fps)
> >> (+) Audio --aid=1 (mp2 2ch 48000Hz)
> >> AV: 00:00:01 / 00:00:01 (98%) A-V: 0.000
> >> Playing: /dev/shm/seg04.mpeg
> >> (+) Video --vid=1 (mpeg2video 720x576 25.000fps)
> >> (+) Audio --aid=1 (mp2 2ch 48000Hz)
> >> AV: 00:00:01 / 00:00:01 (98%) A-V: 0.000
> >> Playing: /dev/shm/seg05.mpeg
> >> (+) Video --vid=1 (mpeg2video 720x576 25.000fps)
> >> (+) Audio --aid=1 (mp2 2ch 48000Hz)
> >> AV: 00:00:01 / 00:00:01 (98%) A-V: 0.000
> >> Playing: /dev/shm/seg06.mpeg
> >> (+) Video --vid=1 (mpeg2video 720x576 25.000fps)
> >> (+) Audio --aid=1 (mp2 2ch 48000Hz)
> >> AV: 00:00:02 / 00:00:02 (98%) A-V: 0.000
> >> Playing: /dev/shm/seg07.mpeg
> >> (+) Video --vid=1 (mpeg2video 720x576 25.000fps)
> >> (+) Audio --aid=1 (mp2 2ch 48000Hz)
> >> AV: 00:00:01 / 00:00:01 (98%) A-V: 0.000
> >> Playing: /dev/shm/seg08.mpeg
> >> (+) Video --vid=1 (mpeg2video 720x576 25.000fps)
> >> (+) Audio --aid=1 (mp2 2ch 48000Hz)
> >> AV: 00:00:01 / 00:00:01 (98%) A-V: 0.000
> >> Playing: /dev/shm/seg09.mpeg
> >> (+) Video --vid=1 (mpeg2video 720x576 25.000fps)
> >> (+) Audio --aid=1 (mp2 2ch 48000Hz)
> >> AV: 00:00:01 / 00:00:01 (98%) A-V: 0.000
> >> Playing: /dev/shm/seg10.mpeg
> >> (+) Video --vid=1 (mpeg2video 720x576 25.000fps)
> >> (+) Audio --aid=1 (mp2 2ch 48000Hz)
> >> AV: 00:00:01 / 00:00:01 (98%) A-V: 0.000
> >> Playing: /dev/shm/seg11.mpeg
> >> (+) Video --vid=1 (mpeg2video 720x576 25.000fps)
> >> (+) Audio --aid=1 (mp2 2ch 48000Hz)
> >> AV: 00:00:00 / 00:00:01 (91%) A-V: 0.000
> >> Exiting... (Some errors happened)
> >>
> >>
> >> I've verified that at least audio track exist, but you better to run
> >> your own liestening test to hear if audio get desynchronized over
> >> longer runs
> >>
> >> What worries me is audio. If segmented audio muxer cut it differently
> from video we will get desync.
> >>
> >> May be setting labels at specific intervals and then using "write new
> file at label" checkbox is better idea?
> >>
> >>
> >> 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
> >>
> >> Up to interested party, I guess.
> >>
> >>
> >> 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
> >>
> >> Yes, I was thinking about this, but unfortunately without any testable
> idea. Sorry.
> >>
> >>
> --
> Cin mailing list
> Cin at lists.cinelerra-gg.org
> https://lists.cinelerra-gg.org/mailman/listinfo/cin
>
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