QLC+ on RPi: use case and a few questions

[imm]

I’ve been helping a friend of mine to implement a fixed DMX+video installation with the help of a raspberry pi 3 and QLC+. The installation is an “escape game” where several people are locked in a room equipped with lights, sensors and two independent screens, the people have one hour to solve the different enigmas in the room to escape. QLC+ on the Rpi handles all of the two screens, DMX, scenes, sounds and can be remotely controlled by an iPad, via the web-interface.

In the beginning of the project we were considering using RPi only for video playback, but as the project evolved we found that, a single RPi board could handle all that stuff... Even if we’re pushing the Pi and QLC+ a little to their limits all is performing quite well for this critical use!

Yet we have a few questions for the community:

1) We saw that a new version of QLC+ has been released. Is this version available on the RPi platform? If yes, how to upgrade?

2) We’re using scripts to launch/stop videos and sounds. The scripts in QLC call bash scripts to play videos

#!/bin/bash
omxplayer.1 --no-osd --aspect-mode fill --loop --vol ${2:--0} -o both --display=5 $1

or to stop them

#!/bin/bash
killall play_hdmi
killall omxplayer.1
killall omxplayer.bin.1

(the omxplayer binaries have been duplicated to use the killall command, the simplest option we found)

Sometimes the script subsystem in QLC+ seems not to respond, i.e. no more video will display (the DMX show continues), forcing the operator to reboot the RPi… This problem seems to happen in a completely random manner.. Do anybody has an idea what could go wrong and/or how to debug?

3) We followed the instructions to use omxplayer, as given on the forum.

viewtopic.php?t=9021

We cannot get rid of the console tho, since following the instructions in section 2. give an error message saying that xterm-256color has no blank command. Is there a workaround for this?

[mcallegari]

1) We saw that a new version of QLC+ has been released. Is this version available on the RPi platform? If yes, how to upgrade?

The latest version for the Raspberry Pi is 20161227. You should have received and email with the download links. There isn't a new one after that.

2) We’re using scripts to launch/stop videos and sounds. The scripts in QLC call bash scripts to play videos
...
(the omxplayer binaries have been duplicated to use the killall command, the simplest option we found)

Why ?

Sometimes the script subsystem in QLC+ seems not to respond, i.e. no more video will display (the DMX show continues), forcing the operator to reboot the RPi… This problem seems to happen in a completely random manner.. Do anybody has an idea what could go wrong and/or how to debug?

Random usually means evil, so I personally don't have a specific idea right now. You could provide more details about the usage you make of those scripts, in particular the timings. Killing a video decoding process and starting another right after might not be appreciated by the VC4 unit of the Pi. Maybe a reasonable sleep command could give it some breath ?

3) We followed the instructions to use omxplayer, as given on the forum.
viewtopic.php?t=9021
We cannot get rid of the console tho, since following the instructions in section 2. give an error message saying that xterm-256color has no blank command. Is there a workaround for this ?

Maybe the syntax has changed from when I wrote that post. Have you checked the setterm man page or Google it ?