[FFmpeg-user] Causes of color bars?

[Devin Heitmueller]

On Tue, Jul 14, 2020 at 10:41 AM Simon Roberts
<simon at dancingcloudservices.com> wrote:
>
> Well, I found out more. If I connect the camera to the input through the
> cabling, but remove the splitter, it works as is, with the command I
> originally used i.e. autodetecting the Hp59 signal. If I include the
> splitter, the decklink mediaexpress still works, and indicates 59.94
> progressive, but ffmpeg doesn't see it.
>
> Could the splitter be changing the pixel format? I'll read about those and
> see if I can move forward that way.

So a splitter typically won't change the pixel format, but depending
on what the splitter's EDID announces to the sender, could result in
the sender changing what it sends.  So for example, the camera may
send RGB when directly connected to the Decklink card because the
Decklink card indicates it supports both YUV and RGB.  But then put
the splitter in the middle, and the splitter indicates that it only
supports YUV, and thus the net effect is the camera sending YUV
instead (which then gets forwarded to the decklink card).

Note, the above scenario is just an example - I don't know what your
specific splitter actually announces in its EDID, nor what your camera
supports sending.

Devin

-- 
Devin Heitmueller, Senior Software Engineer
LTN Global Communications
o: +1 (301) 363-1001
w: https://ltnglobal.com  e: devin.heitmueller at ltnglobal.com