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Stumpster
05-15-2008, 08:24 AM
I would like to see the product line have lower video latency.

Under (2) frames would be great. May not be possible at that price point but many people purchasing are caught by surprise when they try to take cameras to the screen. I simply can't use it without a Hi-Rez swicher on the front end and use the Tricaster behind it to switch a seperate show for record.

Even after taking all the proper steps to reduce latency, this is one of the biggest shortcomings of the product line in my opinion.

ted
05-15-2008, 09:29 AM
How many frames are you getting?
There are so many factors that add latency.

Quiet1onTheSet
05-15-2008, 11:43 AM
I would like to see the product line have lower video latency. Under (2) frames would be great. May not be possible at that price point but ...The TriCaster's video latency is fantastic at any price, at just under 3 video frames -- that's just 1/10 of a second or better.

What make/model cameras are at play, and do you have "image stabilization" or some other processing turned "ON" in the cameras' menus, that might be adding to TriCaster's mere "3-frames-or-less" of said latency?

Q1

Stumpster
05-15-2008, 01:53 PM
Thanks guys. All I can tell you is this. I work in the AV Corporate industry and just put a D-50 through the Tricaster and took it to the screen direct with no switcher in-line (and kept the output native) just to have some fun on setup. The latency in the unit is just too much and a savy TD will call you out on it. Bypass the Tricaster and run it through an Encore or even my Edirol V-440HD instead and it looks tight. I am looking for ways to make this great product fit in the land that I live in "so to speak". I can't fool the TD and get away with this kind of latency. The unit is great and is making me money but I have to be realistic about how I deploy it.

For the money the product line does alot of cool stuff. That's why I support it and bought it. The reality for me at this point in the process is that it needs to "do it's thing" behind a high-end switcher. It would be nice to put it out front for a show on a tight budget.

That's why I would like to see the frame delay lowered if that is possible.

CreatvGnius
05-15-2008, 06:57 PM
Thanks guys. All I can tell you is this. I work in the AV Corporate industry and just put a D-50 through the Tricaster and took it to the screen direct with no switcher in-line (and kept the output native) just to have some fun on setup. The latency in the unit is just too much and a savy TD will call you out on it. Bypass the Tricaster and run it through an Encore or even my Edirol V-440HD instead and it looks tight. I am looking for ways to make this great product fit in the land that I live in "so to speak". I can't fool the TD and get away with this kind of latency. The unit is great and is making me money but I have to be realistic about how I deploy it.

For the money the product line does alot of cool stuff. That's why I support it and bought it. The reality for me at this point in the process is that it needs to "do it's thing" behind a high-end switcher. It would be nice to put it out front for a show on a tight budget.

That's why I would like to see the frame delay lowered if that is possible. OK, Stumpster -- here's something to consider: Do you suspect the keenest of TDs can discern the visual difference between "just under 3 frames latency", versus "2 frames latency exactly", during a live-shoot scenario?

-PeterG

Quiet1onTheSet
05-15-2008, 07:20 PM
OK, Stumpster -- here's something to consider: Do you suspect the keenest of TDs can discern the visual difference between "just under 3 frames latency", versus "2 frames latency exactly", during a live-shoot scenario?

(Hmmm. I wonder if Stumpster thought of having his unit tested by some keen TD, to investigate whether he's really observing an abnormality of something considerably greater than 3 frames per second latency.)

Q1

Stumpster
05-15-2008, 09:54 PM
I would like to know from the engineers if this is something that can be improved upon in the future. It might not be realistic at that price point.

If not, I can work around it and use the product in a way that makes my client happy. That's all that matters to me in the end and the only opinion that carrys any weight.

So, how about it Newtek?

ted
05-16-2008, 01:22 AM
Stumpster, I feel your pain. People throw techie terms about all the time. ANY digital switcher or other digital gear will add about 2 or more frames, per piece.
At some point you just gotta tell them "that's a digital fact, you didn't know that" ? Then just grin. :D

There are a lot of tricks, like not putting the projected image directly behind the speaker and using better projection systems, but there is no digital option that has ZERO frame delay. I promise.
People gotta deal with the digital reality or tell them to get educated. :hey: They actually make audio delay gear for mission critical situations or picky clients. It's part of the technology. Do they want to pay for that level of acuracy?

You still haven't mentioned how many frames. You could do a simple recording on a camera and tell if you are within a reasonable digital delay or if you have other issues.
Best of luck.

PIZAZZ
05-16-2008, 09:16 AM
The quick and short of it is this....

Analog to Digital conversion on input
Digital to Analog conversion on output

1 frame to Sync inputs
1 frame to Sync output

2 frames minimum possible. This is the best the technology will allow as of today.

That is only possible if you are using genlocked cameras which make it easier for the input to sync.


I can tell you from personal conversations with the owner of NewTek. Latency is ALWAYS something they are concerned with. They are continually working to improve it.






Stumpster, I come from the same industry as you. In order to maximize your investment in the TriCaster line you are doing the exact thing we do. The next thing I would suggest you always do is make absolutely sure that when you design an event, minimize the extra gear between the TC and Projector. The Barco HD18 units we used at NAB had 1 frame of latency and that was because we fed it straight from the TriCaster on stage. There was no Folsom, no DA, no router switcher between the TriCaster and the projector. Also, don't use cheap smaller LCD projectors. If you have to use the lesser projectors for budget reasons then make sure to feed them their native resolution to minimize their scaler from adding more latency.

Our viewing distance was 10' from the screen and though I could tell there was some latency, it was no where near what I have seen in the past before getting involved producing events for NewTek.

In a Large room setup, ie. 1000-2000 people with IMAG screens on the sides, you will not be effected by the 2-3 frames of latency.

Stumpster
05-16-2008, 10:00 AM
Thanks Ted,

I have read the various ways to actually determine the delay but have not attempted to actually get that exact number figured out. It does take about 180 milliseconds of audio delay to get the video to sync with the audio during the test. So it is around 5 frames? I have hooked the unit directly to the projector native at 1024x768 with no other gear in-line and it's hard to look at...like watching a Japanese movie with the voice over....this is with a single latent free broadcast camera.

Using the same projector with my hi-rez switcher it looks great. No genlock in play for either scenario.

The manufacturer told me that my switcher has (1) frame of delay.

Does anyone know what the Tricaster exact spec is? If it is (3) frames or less then I suspect that I have a lazy unit. (3) frames of delay would be fine if that was the total.

I have also observed the same latency on a CRT monitor hooked up to the output of the unit as well as a Sony production monitor hooked up to the component output. I would hope that this would give me a true sense of how responsive the unit is on it's own.

I am open to any tricks to tweek the unit if that is possible.

jcupp
05-16-2008, 10:10 AM
With genlocked cameras it is precisely 2 frames. If your cameras aren't genlocked it will be between 2 and 3 frames. Edit:for the analog outputs

Stumpster
05-16-2008, 11:25 AM
Thanks,

Are you refering to the component/composite output? Does that have lower latency than the DVI output?

This is a single camera setup.

Is there a way to genlock the camera to the Tricaster even though it dosn't have a true sync connection?

PIZAZZ
05-16-2008, 11:50 AM
Thanks,

Are you refering to the component/composite output? Does that have lower latency than the DVI output?

This is a single camera setup.

Is there a way to genlock the camera to the Tricaster even though it dosn't have a true sync connection?

YES In my experience the Component/Composite output has lower latency IF your projector does not have to drastically rescale the Analog input to display it.

Regarding setting up Genlock....
Take the composite output of the TriCaster and run it as your blackburst for your camera chains to sync to.

Quiet1onTheSet
05-16-2008, 03:09 PM
The Barco HD18 units we used at NAB had 1 frame of latency and that was because we fed it straight from the TriCaster on stage.
Unless otherwise informed, we can assume you used the TriCaster's DVI output, with TriCaster set to the Barco's native display res. That's really terrific, Jef.

Q1

PIZAZZ
05-16-2008, 03:18 PM
Unless otherwise informed, we can assume you used the TriCaster's DVI output, with TriCaster set to the Barco's native display res. That's really terrific, Jef.

Q1

NO. That would be a WRONG thing to assume.

I fed them SDI input or YUV as backup.

Quiet1onTheSet
05-16-2008, 03:24 PM
NO. That would be a WRONG thing to assume.

I fed them SDI input or YUV as backup.Wait! You employed the coveted TriCaster BROADCAST™?

Now you've got me speculating that TriCaster BROADCAST has a low-level latency advantage with its SDI output: owing perhaps to the fact that one isn't dealing with a D/A (digital-to-analog) converter in the way. Result: lower-latency trumping that of an analog YUV output.

I would never have thought of that, were it not for your eye-opener of a post above, Jef. But then again, I may be guilty of *another* wrong assumption...

Q1
:rolleyes:

Stumpster
05-16-2008, 06:52 PM
Thanks Jef,

I'll try using the composite output as the blackburst as you suggested and report back. If that can get it to (2) frames then I should be good.

Stumpster
05-30-2008, 09:10 AM
Connecting the output of the Tricaster to the sync input on the camera did lower the latency. I can see a difference.

Thanks!

PIZAZZ
05-31-2008, 12:06 PM
Good to hear it worked out for you.
Sometimes the simplest solutions actually do work out...

Quiet1onTheSet
05-31-2008, 01:12 PM
Connecting the output of the Tricaster to the sync input on the camera did lower the latency. I can see a difference. Thanks!
Terrific. Glad to hear of the latency improvement you've achieved, Stumpster. Here's hoping the difference you see is appreciable in measure.

Q1