Previous topicNext topic

Start image sequence export at specified time

Suggestions for new features for Magic.
Post Reply
jstark
Posts: 9
Joined: Tue Oct 11, 2016 7:36 pm

Start image sequence export at specified time

Post by jstark »

Hey,

Would it be possible to add the functionality to start a .png export at a specified time?

I manage a planetarium and we've used magic to create 3 light shows so far and we love the software. Our system runs at 4K, 60 fps so rather than export a low resolution .mp4 we export a series of .png files and use our planetarium software to encode and slice video files. Overall it works very well but when we run 4k renders on some of our more graphics heavy stuff it's not uncommon for us to crash magic even on our beefy production station computers. If we could pick up roughly where we left off rather than trying again and hoping it would make our workflow much easier. We could find the point where the two renders overlap and use a bulk rename utility to line up the file names.

Thanks for all your work, you guys have an awesome product.

Also, as a side note, we're presenting our methods using your software at the annual GLPA conference this fall. It's a planetarium conference with roughly 180 delegates so cross your fingers that goes well. Thanks again.
Magic
Site Admin
Posts: 3440
Joined: Wed Apr 09, 2014 9:28 pm

Re: Start image sequence export at specified time

Post by Magic »

Cool, sounds fun!

We discussed this issue a bit here: viewtopic.php?f=4&t=289&p=5173#p5172

What kind of computer(s) are you using? You would need a REALLY high-end graphics card with lots of memory if you want to do complicated 4K renders...
jstark
Posts: 9
Joined: Tue Oct 11, 2016 7:36 pm

Re: Start image sequence export at specified time

Post by jstark »

Sorry I missed that thread. From a cursory read through it looks like I'll be able to use that to get the results I'm after. One downside to this method is that I'm guessing (haven't tried it yet) that the playlist times will all be off. We use playlists to switch between scenes and adjusting the audio to all start a minute earlier will probably mean my scene change timing will all be off by a minute.

For now my workaround will be to just use a master scene, and plug all the individual scenes into a multimix that switches displays when I want using a time code audio track, which would remove the need for using the playlist feature.

Thanks for the quick reply.

Regarding GPUs, one station is using 2 SLI connected Nvidia geforce gtx 980 ti, another is using 2 crossfired radeon r9-280x, and I forget what our 3rd station is running but it tends to be the most reliable of the three stations so nothing shy of those two setups. One nice thing about running a 4k planetarium is that I have access to the fairly high end machines needed to run the system.

Edit: You asked about computers and I just mentioned GPUS, they also very from 16-32gb of Ram and are all running dual xeon E5 cpus. I know what we're doing isn't necessarily the intended use for your software so we're not surprised when we come across these types of hiccups. It's still a heck of a lot faster than the old method of hard coding the timing of the beginning of an effect with some moment in the music.
Magic
Site Admin
Posts: 3440
Joined: Wed Apr 09, 2014 9:28 pm

Re: Start image sequence export at specified time

Post by Magic »

Sorry, when I said memory I meant graphics card memory (VRAM). I guess I'm surprised that you're encountering crashes with the graphics cards you mentioned since they are high-end. But I suppose it is possible, depending on the amount/type of effects you're using...
jstark
Posts: 9
Joined: Tue Oct 11, 2016 7:36 pm

Re: Start image sequence export at specified time

Post by jstark »

Yeah we try to make sure we're as efficient as possible with only including what's actually being drawn in our scenes but we try to make the effects pretty visually stimulating so they can get pretty complicated at times. We've come to realize that various trails effects are one of the biggest resource hogs because of the number of gradients they produce, which takes a toll on the VRAM. Here's a link to one of the songs for our latest show.

https://vimeo.com/254923383

PW is: Queen2018
jstark
Posts: 9
Joined: Tue Oct 11, 2016 7:36 pm

Re: Start image sequence export at specified time

Post by jstark »

The workaround you suggested in the other thread was successful for my purposes. I was right in that it doesn't work when using the playlist, but using a multimix module to switch between scenes instead of the playlist functions well as a workaround and I'm able to begin renders at any point now. Thanks again.
Magic
Site Admin
Posts: 3440
Joined: Wed Apr 09, 2014 9:28 pm

Re: Start image sequence export at specified time

Post by Magic »

We've come to realize that various trails effects are one of the biggest resource hogs because of the number of gradients they produce, which takes a toll on the VRAM
Trails do use more memory but not because of gradients. Any Trails-type effect will store one or more copies of previous frames in order to blend them with the current frame.

In VRAM, the contents of an image are completely irrelevant, because all images are stored uncompressed. In other words, every image always takes up width*height*4 bytes of memory, even if the image is completely black.
Here's a link to one of the songs for our latest show.
https://vimeo.com/254923383
In your video, the image is masked by a circle in the center. If this is always true, you should export your .png sequence at 2160x2160, not 3840x2160. You will save a LOT of memory and time, and the renders will probably crash less (if at all).
jstark
Posts: 9
Joined: Tue Oct 11, 2016 7:36 pm

Re: Start image sequence export at specified time

Post by jstark »

That's good to know about the content of the image. It's good to know that visual complexity isn't necessarily the problem, but the layering/quantity of effects being used. Do you know if it's more efficient to duplicate an effect or a scene? Say we string together 10 modules to create an effect and we wanted 5 versions of that effect on the screen. Would it be better to copy and past those 10 modules 5 times, or make a new scene and call the first scene five times? Or does it not make a difference?

The circle mask is always present, but full dome 4k is different than standard 4k. When we render out our scenes we render them at 4096x4096, which is what is considered 4k for domed theaters. So the circle mask is where the video would meet the rim of the dome. 2048x2048 (roughly equivalent to your suggested resolution) is only considered 2k in my business, which our computers handle no problem. That probably explains why you were surprised that we're crashing it. We're working with roughly twice the pixels of standard 4k. The 2k renders (2048x2048) only take us about 20 minutes of rendering per minute of video and never crash on us.
Magic
Site Admin
Posts: 3440
Joined: Wed Apr 09, 2014 9:28 pm

Re: Start image sequence export at specified time

Post by Magic »

Do you know if it's more efficient to duplicate an effect or a scene? Say we string together 10 modules to create an effect and we wanted 5 versions of that effect on the screen. Would it be better to copy and past those 10 modules 5 times, or make a new scene and call the first scene five times? Or does it not make a difference?
Duplicating and/or copying modules is usually the *least* efficient. It's much better if you can reuse modules, for example as SceneModules: https://magicmusicvisuals.com/downloads ... eneModules
We're working with roughly twice the pixels of standard 4k. The 2k renders (2048x2048) only take us about 20 minutes of rendering per minute of video and never crash on us.
Gotcha. That makes sense.
Post Reply