BATC Forum

Odd topic, yeah i know, but...

I was looking at using one Raspberry Pi4 to do multiple tasks in GB3KM.
The concept is using the USBTV0007 Easycap to take in Composite video and output this on HDMI with the correct aspect ratio, this does a better job than the Composite>HDMI converters off ebay etc.
The original idea was to use two easycaps on one pi4 with two instances of mplayer, unfortunately i could not find any means to select the display for video out.
Fortunately there is an option for this in vlc

To display an easycap input on HDMI1 port simultaneous with the Ryde receiver on HDMI0 you can use this command, simples!
vlc v4l2:///dev/video0:width=720:height=576 --mmal-display=hdmi-2

One unfortunate problem is that it does not always show the noise like it did with mplayer when i last tested it, maybe a v4l2 update broke that...

Rob
M0DTS

A the post above i'm using both HDMI outputs for GB3KM, but also need to use separate sound for the Ryde bit...
I needed Audio separate from the HDMI, from what i have read it seems that the PWM used for the IR remote causes problems with using the on board headphone output.
I added one of the white usb audio dongles, uncommented and modified this line right near the end of player.py:
vlcArgs += '--aout alsa --alsa-audio-device hw:CARD=Device,DEV=0 '

Now have video on HDMI and sound on the usb device from Ryde Rx.

Rob

Hi Rob,
There is a rough plan to make audio output properly configurable in the future, its issue #46. If you learn anything interesting it would be handy if you could stick it in the issue for reference when I get that far.
Tim

I've figured this now works for HDMI-Video and analog audio output without another USB audio adaptor.
I think i missed the "--aout-alsa" on previous tests.

in player.py:
vlcArgs += '--aout alsa --alsa-audio-device hw:CARD=Headphones,DEV=0 '

Rob

That works well Rob. I've found you can adjust the volume using alsamixer while SSH'd in as well. My HDMI monitor has pathetic speakers built-in so this really helps.

Many thanks,

Martin - G4FKK