Docker Container for Jetson Nano?

Channels DVR Server
#1

Any thoughts on this? Using jetson-ffmpeg should be able to transcode any 4k stream real-time.

I'm currently looking into creating a container to transcode all my MPEG-2 to HEVC (using .edl) but thought I'd ask first.

#2

Since the RPi4 image they've released is aarch64, it shouldn't be too difficult.

If you're looking to do that for recordings made from Channels, there's an easier way. Channels' version of comskip outputs ffmeta and ffsplit files in a recording's comskip log directory. If you want to introduce chapter markers for commercials, use the ffmeta file; if you want the commercials removed, use the ffsplit file with a 2-pass script to do that.

(Just a note: HEVC doesn't offer much more compression/quality over AVC for video up to 1080p; savings are really evident for 4K and higher.)

#3

I got it compiled and working with a test case. ffmpeg was able to strip and generate an H.264 mp4 file from MPEG-2 at about 4x speed. Not bad for a $69 device connected to a NAS for storage.

I haven't yet looked at comskip code but wonder if if it can be sped up using the h264_nvmpi codec.

Thanks for the tip on ffsplit - it works easily. Here's the simple commands:

jetson-ffmpeg -i /mnt/syno/741/741.mpg $(cat video.ffsplit)

jetson-ffmpeg -f concat -safe 0 -i <(for f in ./*.ts; do echo "file '$PWD/$f'"; done) -c:v h264_nvmpi -c:a ac3 /mnt/syno/741/741_stripped.mp4

#4

Just beware that comskip is not 100% accurate. You can adjust the commercials in the Channels web UI, but that will not update the files in the comskip log directory. In that case, you would want to:

  • Use an EDL file like you originally planned
  • Ensure the EDL Export option is enabled in the web UI
  • Use the EDL file that is created alongside the recording in the TV or Movie subfolder, rather than any file in the comskip log directory. (This is because that EDL file is generated from Channels' internal DB, which is updated when you modify the commercial markers in the web UI; the original files from the comskip log directory are not updated when you verify the commercials.)

Hope this helps.