View Full Version : Extract SD res from 4K .. live


Marcello Mazzilli
April 17th, 2016, 03:22 PM
Had an Idea.
I shoot with 3-4 cameras during event (meetings etc), have a live switcher and stream on the web, in SD resolution.
Now... WHAT IF.... I had just ONE CAMERA... a 4K camera.... at the bottom center of the room... Just had a still wide angle showing the whole room, the podium and the speakers table... and then cut out just the podium and the speakers table. And the third angle could be the wide one... ?

Is there some sort of box (switcher, card, mixer, device...) Ican input 4K video and exit on 3 different cables 3 different SD angles cut out/resized from the same single 4K shot? I could then switch between these three angles. This could dave me from bringing 3 cameras...ONE CAMERA would do the trick!
Any idea?

Ervin Farkas
May 27th, 2016, 10:06 AM
It can be done.

Split the signal coming out of your camera using something like MuxLab HDMI 1 x 4 Splitter 500421 B&H Photo Video or similar if using SDI.

Use three Magewell USB adaptors Magewell XI100DUSB HDMI USB 3.0 Capture Dongle XI-100-D-USB-HDMI or the SDI version if using SDI.

Use vMix software http://www.vmix.com/software/ to resize and crop/pan/tilt or whatever you want to do with the inputs.

Switch between inputs using vMix. Use the same software for streaming.

Would I do it this way? Probably not... using individual cameras would be my preference, especially since you already have the cameras.

Marcello Mazzilli
May 27th, 2016, 10:11 AM
Thanks.. I didn't know about that software.. seems great....
I think the solution will NOT wirk because the HDMI to USB dongles are not 4K though... I need at least one to get the full size input. It can probably can be found somewhere.
thanks

Ervin Farkas
May 27th, 2016, 10:15 AM
It WILL work!

I forgot one step - set the HDMI output from your camera to HD.

Most cameras will record to one format and output another.

Marcello Mazzilli
May 27th, 2016, 10:37 AM
In that case I will loose resolution... I want to keep 4k all the way so I can zoom more..
Also I need and HDSDI to HDMI 4K converter in between
M

Ervin Farkas
May 27th, 2016, 10:45 AM
Lose resolution? Didn't you say you're streaming SD?

And the Magewell dongles are available in SDI version too, no need to convert SDI to HDMI.

Magewell XI100DUSB SDI USB 3.0 Capture Dongle XI-100-D-USB-SDI

Marcello Mazzilli
May 27th, 2016, 10:53 AM
The dongles are in HDSDI too but the splitter is only in HDMI. Probably there is another one.

What I need to do is to stream in SD but I need 4K to zoom in the maximum possible

Let's say I am the back of the room and get people sitting (from the back), the guy speaking at the bottom left, the table at the bottom right, If I keep 4K signal into the DVE system I can use it to zoom and extract a close up of the guy speaking. If I have HD signal I will not be able to zoom as much..

Jeff Pulera
May 27th, 2016, 01:18 PM
LiveStream has announced the MEVO camera system. It has a 4K sensor, and with your iPhone, you mark smaller parts of the image as separate areas then switch between them, same thing you are suggesting. So it utilizes the 4K source to simulate a multi-camera shoot on the fly and streams the results in 720p.

Info here - https://getmevo.com/features/camera

I believe this was meant to ship already, but got delayed.

Thanks

Marcello Mazzilli
May 27th, 2016, 02:02 PM
Seems it was a good idea then! ;)

Jeremiah Rickert
December 10th, 2016, 02:35 AM
What's funny is that this concept is a coming thing in live sports. I saw a demonstration of a device at a soccer stadium during a match that had 16 lenses on it, each one calibrated to point in a slightly different angle. They set this contraption halfway up the stands, midfield, and it could simultaneously record the entire field at the same time, and any part of the field could be isolated in 1920x1080 and replayed. It was a way of guaranteeing that no play (or foul behind the play) was missed by cameras. Not sure when this thing is going to be common, but it was kinda mind-blowing.