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10 of the same video bug ?


Alex Ramos

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This is no heavy load at all.

And there's nothing normal about this.

 

Why can I only play 10 instances of the same video ? This is not a display load problem as I can play many other files as long as it not the same.

 

Why is that if I start the same file all at the same time  it can run over 100 windows, But if the file start at different times there's a limit of 10 instances ?

No mater if the file is placed 1second  apart or in random order there is always a limit of 10 instances of the same file.

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I don't see where WATCHOUT is failing, but It does seem like your pushing the computer system past it's capabilities and the computer is failing to run the videos properly. I like to see how many video layers I can run at the same time on my computers, which helps me to manage their limits and clients expectations.

What is the purpose of your experiment?

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Will it make a difference if you put the video file in a composition, and use that instead, so it's the composition that are copied multiple times? I haven't tried it, but normally that's my approach, just to make sure that if anything needs to be added to the footage, I just have to do it one time. Question - what size and codec have you been using?

 

Best regards Chris

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I don't think some of you are getting thats happening here.

Take another look to the 1st video and and this new one.

 

And still remains the question.

Why 60 videos at the same time, OK?

Why 15 videos ate the same time, OK?

Why 15 videos one at the time not OK?

Why 10 of a kind + 10 different + 10 different OK and not 30 of the same not OK?

 

Vollmers

Im using HAP 55.3Mbs but tried with MPEG-2 and its exactly the same, only I can play more files if HAP.

Tried the composition and behaves the same way.

 

mindopera

The purpose is to find limitation on the software and on the hardware.

In this case is clearly a software limitation.

 

https://www.youtube.com/watch?v=YNeURaokJ8c&feature=youtu.be

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The reason you can play a very large number of the same video all at the same time is that WATCHOUT will recognize this duplication and really only play a single instance internally, while displaying those same pixels in 100 different places on stage. Thus it will only decode that video once (which is very the heavy lifting happens), and stomp out those same pixels many times (done on the GPU, so this is very fast).

 

Note that this optimization works only if all the specs in the cues are identical, and the cues start at exactly the same time.

 

 

Mike

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Hi Alex,

 

What you are doing now, is the way I test how the hardware limitation.

not software.

 

as Mike mention, play same video at the same time, it treat playing 1 video file(reading same sector from harddisk)

but if you placing the same video in different time(for example, 10), it play 10 video file, reading different sector from harddisk.

 

so 10 x 55.3MB = 553,

even i am using samsung 850pro, maximum read speed is 550MB/s

i am sure it excess my hardware limitation.

 

Can you tell us what model of Harddisk/SSD you are using?  and connection type, sata3, M.2 or?

and Motherbroad.

 

If you have faster SSD, please give it a try, and you will know the result.

 

just my 2cents.

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The reason you can play a very large number of the same video all at the same time is that WATCHOUT will recognize this duplication and really only play a single instance internally, while displaying those same pixels in 100 different places on stage. Thus it will only decode that video once (which is very the heavy lifting happens), and stomp out those same pixels many times (done on the GPU, so this is very fast).

 

Note that this optimization works only if all the specs in the cues are identical, and the cues start at exactly the same time.

 

 

Mike

 

This doesn't account for the fact that the problem is fixed when he has the exact same cue setup(one video multiple times) and then changes the video file on five of them and the problem goes away.

 

I'm travelling and don't have a rig with me to test right now but now I'm very curious.

 

Z

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My understanding of how Watchout works is what Mike says.  However, based on this when you reach the 10 file limit you shouldn't be able to add other files.  That is the interesting part of this.  Does anyone have an explanation of why Alex can change to a different file and add another 10 instances?

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Im sorry guys if Im not clear when trying to put out my case, and the sound is not the best.

I got the problem isolated now.

 

Anyway, I think this last video clearly shows a software problem as well as the hardware reaching its limits.

 

Also I sharing the project in dropbox if you wana give it a  run and see if you can replicate the problem.

 

It includes the project file and the media. All around 700Mb

 

https://www.dropbox.com/s/ab43bknonhyakpa/10%20of%20the%20sabe%20file%20bugg.rar?dl=0

 

Why I do this ? To much free time and its fun messing around with the software and hardware trying to crash it, I believe its the best way to know the limits.

I have 70 displays, 90 watchpax and 20 people operating it and creating problems every day, I better know the limits of the system and what I can and cannot do.

 

Morgan Wang

Its the exact same is I use 10kbs. I've tried.

Adata SP900

Gigabyte Z77 D3H

 

https://www.youtube.com/watch?v=ZS32gCtEtC8

 

Hope this clears it.

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Hello! 

Thanks for taking the time to record a video and share, it makes everything a lot easier to understand. While I don't (yet) have any explanation for what is going on here, there are a few things worth pointing out.

The cues are obviously free running since the videos still play after hitting a pause cue, are they also looping? I will not go into the details here, but by checking the looping checkbox, playing the cue will use more resources (primarily in the form of higher memory consumption), as compared to playing it non-looping. 

There are also three different cases when playing movies that affect performance in a non-obvious way: 

1. As Mike pointed out earlier, if identical cues (identical spec, and same movie file) start at exactly the same time, Watchout will detect this and will only decode one instance. 

2. If playing identical cues, that are not started at the same time, they will play as separate instances, meaning that the number of decoders decoding the movie will be the same as the number of cues playing at the same time. However, if there is enough memory in the computer, the file will end up in the Windows file cache, and it will only have to be read from disk once, since all instances of the decoder (except the first one of course) will end up getting the file from the Windows file cache. This means that CPU load will be as high as when playing physically separate files, but disk bandwidth used will in many cases be next to nothing, since the file is only read once for all instances. 

3. The common scenario, when you are playing different files, is the most demanding, since there is no sharing of decoders and the disk cache will not make a difference, since all the files are different. 

 

There is an exception to the above, though. When playing image sequences the Windows cache is bypassed. 

 

Although my points above do not necessarily directly relate to the problems you have experienced, I though it would be worth mentioning them here. 

 

/Erik 

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To me it seems the issue is exactly as Morgan pointed out. As the files are free running and thus theoratically not starting at the exact same time, the software is reading out the exact same sector on your hard disks, and I can imagine you're reaching a bottleneck just there. As this is the only different factor as oppose to running the same cues with different video's in it.

If you still need to play these exact same video's the solution is probably extremely easy : just make some copies of the original file and play these, thus not reading the exact same location on your drive so many times.

 

Could well be, right?

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