omxplayer has 20s delay on raspberry pi live stream

[gitterman]

I am running buster on a pi model B which acts as a door monitor with an attached USB cam. The camera is streamed with mjpg_player on the internal network without any significant delay. I also have a 640x480 car monitor attached to the analog video output, and I am using omxplayer to show the stream on this monitor. Alas, there is a delay of about 20s on the omxplayer output which makes the setup rather unusable. The command line I am using is: omxplayer -r -b --no-keys --live http://$HOSTNAME:8080/?action=stream I have tried to reduce the frame rate by adding --fps 10 before the --live option but no change.

[popcornmix]

Setting the fps higher than the actual rate would be more likely to reduce buffering (although if stream contains timestamps the fps setting will be ignored).

I'd suggest playing with:

  --audio_fifo  n         Size of audio output fifo in seconds
    --video_fifo  n         Size of video output fifo in MB
    --audio_queue n         Size of audio input queue in MB
    --video_queue n         Size of video input queue in MB
    --threshold   n         Amount of buffered data required to finish buffering [s]

But be aware omxplayer is deprecated and will get no updates, so you may be better off with a newer distribution and a supported tool like VLC.

[gitterman]

Thanks for the quick answer, I will give it a try. From my understanding VLC is way much more resource consuming than omxplayer and has its problems when running without a GUI. My doorcam pi runs just from CLI and has no keyboard attached. Tools like omxplayer and streamers like mjpg_streamer are very valuable in these scenarios. The usefulness of a raspberry pi as a headless workhorse in the closet, without a GUI is much bigger than to use it as a desktop because of its lack of power compared to a cheap refurbished notebook. It is a pity that things become so GUI oriented these days.

[popcornmix]

VLC will run without a gui (e.g. from a RPiOS lite image launched from CLI).

[gitterman]

Installation of VLC required 224MB, and it is not supposed to be run as root. I can display the stream with VLC on my desktop PC and on my raspberry 4 GUI, but I did not succeed to get the live stream shown on my attached analog display to my CLI only buster raspi yet. I also found that VLC needs more CPU than omxplayer. So far, I have changed the omxplayer command according to your hints to the one below, which reduces the delay to about 4 seconds, which is acceptable for me. omxplayer -r -b --no-keys -n -1 --video_queue 0.1 --live http://$HOSTNAME:8080/?action=stream