Can your scope do realtime video decoding?

[jokkebk]

Hi!

Here's a cool hack I came up with during the weekend, and surprisingly enough, proved to feasible: Capturing composite video NTSC signal with a USB oscilloscope (Picoscope 2204 to be exact, they have a nice C API), and decoding it realtime to emulate a composite display in software:

https://codeandlife.com/2012/07/31/realtime-composite-video-decoding-with-picoscope/

I'm not aware that this would'be been done before? I've seen serial decoding and video signal analysis using oscilloscopes, but not video signal decoding. It was a fun project, and now I don't need to get a second display to view graphics from my Raspberry Pi, as I can just plug it into my oscilloscope and view the picture on PC (granted, the picture quality is only enough for seeing if something works or not)

 

[sky_123]

Nice : ) I didn't realise the RaspPi had SD composite output too.

 

[jokkebk]

Nice : ) I didn't realise the RaspPi had SD composite output too.

Yes, it was a complete surprise to me, too. I had thought the yellow RCA connector was for S/PDIF audio. Also, the Pi can output both NTSC and PAL signal in multiple aspect ratios. Haven't tried that or different resolutions yet, though.

 

[chuckey]

The Dynamco D700 CRO ( late 60s) had this facility on its TV plug-in along with strobing out individual lines. In 1970 I built a even/odd frame decoder so you could inspect the ITS on odd/even fields. (And a 120V pulse amplifier to brighten up the display to view the 2T pulse)
Frank

 

[jokkebk]

Wow, sounds like that one was really ahead of its time! And I thought I had thought up something new when I did that 45 years later.