Latency / Delay


#1

Hi all…

A bit of a technical / user experience question. We are required to interface on a system which is also driving a lighting system (Think F1 lights), where we are required to change the output in-line with a traffic light system.

We have built a Proof of concept using a simple HTML template, however I wanted to see what experiences people had with either HTML or Flash templates, and if either had any known latency that should be avoided. As such we can decide whether to use a flash or HTML producer.

Additionally does anyone have any experience with the no. of frames latency added using HTML/Flash producers with a Blackmagic Duo card? It would be interesting to know how many frames latency the software / hardware introduces

Thanks in advance


#2

The latency is not easy to measure. It also depends on the client’s latency and a lot of other factors. How do you get the cues from the light system? In general the latency of an already loaded template is short. To be precise one would need to have a camera capturing both, the lights and the output of Caspar. In the casparcg.config you can set a few settings to help lower the latency: Switching <embedded-audio> to false gives you one frame less latency but no embedded audio. Then set <latency> to low and <buffer-depth> to 1. That is the fastet setting possible. Problem with <buffer-depth> 1 is, that in any case the hardware is too slow to render the pictures fast enough you will notice a flicker. But a fast machine should not have too many problems.


#3

The signals are received via a solid state relay, and passed through our software to CG.

I’ll try what you suggest, then run through a proper server rather than the screen producer