HELP (QLab video playback issue)

skienblack

Active Member
I'm running QLab on a Mac Pro with three projectors and a monitor for cues. We running small quicktime movies of picture montages. These quicktime movies are in h.264. Some of the montages are also collections of photos that are auto-following through. The program crashes yet leaves the OS intact. We are running QLAb 2.3.6 and OS X 10.6.8. Its not using a lot of ram or cpu. Ideas for a fix? Our show opens Wednesday.

All of our research has indicated this problem was fixed in the most recent release of QLab. And it has been attributed to problems with quicktime.
 
I'm running QLab on a Mac Pro with three projectors and a monitor for cues. We running small quicktime movies of picture montages. These quicktime movies are in h.264. Some of the montages are also collections of photos that are auto-following through. The program crashes yet leaves the OS intact. We are running QLAb 2.3.6 and OS X 10.6.8. Its not using a lot of ram or cpu. Ideas for a fix? Our show opens Wednesday.

All of our research has indicated this problem was fixed in the most recent release of QLab. And it has been attributed to problems with quicktime.

I don't use QLab a lot, but my guess is that it's the H.264 that's giving you problems. Generally speaking, QLab is a lot more stable when you're not running compressed files through it. It's built for uncompressed media, and while it can still play compressed media, it will crash if you ask it to do a lot of simultaneous cues or read a large compressed file. Your best bet is to convert the compressed media to something else, and the problem should go away.
 
I'm running QLab on a Mac Pro with three projectors and a monitor for cues. We running small quicktime movies of picture montages. These quicktime movies are in h.264. Some of the montages are also collections of photos that are auto-following through. The program crashes yet leaves the OS intact. We are running QLAb 2.3.6 and OS X 10.6.8. Its not using a lot of ram or cpu. Ideas for a fix? Our show opens Wednesday.

All of our research has indicated this problem was fixed in the most recent release of QLab. And it has been attributed to problems with quicktime.

What do you have for graphics cards? I had a similar issue with 8 projectors and 2 monitors (oh the wonders of a multi-head...) and our biggest issue with it was that our vRam was not adequate. You might have more success if you fit large/more capable and modern graphics cards... Also I agree that your compression of the media might be a problem. See if un-compressing it susses out the problem, otherwise you might have to upgrade to larger graphics processing capacity.
 
We have 3 nvideA cards with 512 mb each... We will try to use uncompressed videos tomorrow. Another issue we have is when firing two video cues at once, one for each screen, they aren't displaying simultaneously. One is a split second before the others.
 
Email [email protected] and attach logs your files if no one here can help.

(Gotta run, but I'll try and post more later if no one has helped you fixed it, but knowing this group of people someone will have the answer!)
 
Are you using the load command to load your pictures in the program before a rapid fire sequence?

If you are and it's still crashing try replacing h.264 with photo jpeg.
 
The more efficient a codec is, the more resources it will take to encode and decode content compressed using it.
H.264 is reasonably efficient and so takes a fair bit of oomph to decode.

So I second the suggestions of other to try uncompressed content...
 
The program crashes yet leaves the OS intact.

You seem surprised by this, so I'm going to assume you are new to Macs. In OS X all programs operate independently of the OS, thus if and when a program starts acting up, you do not need to re-start the computer. (Yes, there may be exceptions). When I first started on Mac, I called tech support because a program wasn't working properly and I asked the lady if I should re-start the computer to try to fix it. She chuckled and immediately followed my question with one of her own: "you are new to mac, aren't you? Honey, this isn't Windows, you don't need to re-start."
 
You seem surprised by this, so I'm going to assume you are new to Macs. In OS X all programs operate independently of the OS, thus if and when a program starts acting up, you do not need to re-start the computer. (Yes, there may be exceptions). When I first started on Mac, I called tech support because a program wasn't working properly and I asked the lady if I should re-start the computer to try to fix it. She chuckled and immediately followed my question with one of her own: "you are new to mac, aren't you? Honey, this isn't Windows, you don't need to re-start."

I am not new to Macs. I was just surprised that it left the OS intact because it also caused the computer to kernal panic on two occasions. I will send over the log file to QLab support shortly.

When video is decoded by the computer is that process taking place on the VPU or CPU? Because our CPU is not even above 10% usage while we are firing these cues.
 
Nobody's asked yet, but does it always crash at the same point? Can you play the videos in Quicktime simultaneously?

Another thing with Macs that can sometimes cause wacky issues is the PRAM, you can reset it by holding Command+Option+P+R at startup and waiting until you hear the startup chime again. Beyond that, send the video and .cues files to QlabHQ and see if they can replicate it.

And yes, video decoding is offloaded to ("accelerated" with) the GPU on all modern OSes.
 
Nobody's asked yet, but does it always crash at the same point? Can you play the videos in Quicktime simultaneously?

Another thing with Macs that can sometimes cause wacky issues is the PRAM, you can reset it by holding Command+Option+P+R at startup and waiting until you hear the startup chime again. Beyond that, send the video and .cues files to QlabHQ and see if they can replicate it.

And yes, video decoding is offloaded to ("accelerated" with) the GPU on all modern OSes.

The scary thing is that it does not crash at the location. I will try resetting the PRAM. That is a good idea. One idea I had last night was the computer worked flawlessly all day yesterday and got worse as the night went on. Is there maybe some issue with QLab not clearing its RAM or something? Because once the computer is restarted it appears to function for a while.
 
The scary thing is that it does not crash at the location. I will try resetting the PRAM. That is a good idea. One idea I had last night was the computer worked flawlessly all day yesterday and got worse as the night went on. Is there maybe some issue with QLab not clearing its RAM or something? Because once the computer is restarted it appears to function for a while.

Not sure if this was answered or apparent, but are you running the pro or free version? I had some weird problems with the free version which were fixed in the pro edition...
 
Not sure if this was answered or apparent, but are you running the pro or free version? I had some weird problems with the free version which were fixed in the pro edition...

We are running the Pro version. But we have been in touch with Figure53 support for a little over a day now and they have replicated our issue. Hopefully we have a fix by opening tonight. Thanks everyone.
 
I would like to know how this turns out for you. I am working on a show right now that opens in January that will have a similar video setup. (We will however have [hopefully] 6 TV's, 3 Cameras and prerecorded video & images, running off Qlab on a Mac Pro).
 
We are working closely with the developers at QLab. Yesterday at 4:30(3 hours before go) we switched over to using a macbook pro based on a report from the folks at QLab that they were not able to replicate our problem on a laptop but they could on there Mac Pro. The show went off without a hitch last night. I believe there to be an issue with how QLab communicates with the graphics drivers on a Mac Pro.

They were able to replicate the problem so I have no reason to not believe that they are working on a solution. Especially considering we cannot be the only people experiencing this problem.
 
We are working closely with the developers at QLab. Yesterday at 4:30(3 hours before go) we switched over to using a macbook pro based on a report from the folks at QLab that they were not able to replicate our problem on a laptop but they could on there Mac Pro. The show went off without a hitch last night. I believe there to be an issue with how QLab communicates with the graphics drivers on a Mac Pro.

They were able to replicate the problem so I have no reason to not believe that they are working on a solution. Especially considering we cannot be the only people experiencing this problem.

I have had nothing but good experiences with them, and they are quite helpful with this sort of thing. Good you got it fixed, let us know if anything further happens on that front. I also cant imagine this is unique.

We are running the Pro version. But we have been in touch with Figure53 support for a little over a day now and they have replicated our issue. Hopefully we have a fix by opening tonight. Thanks everyone.

Im pretty sure that this is the only way to do video...
 
I, too, ran 4 outputs to 4 tvs using qlab on a show a year ago, and I could never get the tvs to sync up when firing simultaneously. I was using an early 2010 Mac Pro, and it looked awful, but there just wasn't anything I could do to figure out how to fix it. Please let us know if you can figure this problem out with the Mac Pro
 

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