Advice for a Very Big LED Wall

[HectorCruz]

Hi everyone! I have a project involving an huge LED wall that is 80 x 4 meters in size. (35800px x 2400px aprox) :0 Has anyone used Isadora for this type of setup? I'm wondering how it could be accomplished. One option is to use fancy servers like Disguise, but I want to maintain the flexibility and real-time visual experimentation that Isadora offers for compositing. I feel comfortable using Isadora for this project. Alternatively, in larger setups like this, it would be better to simply play files without using Isadora. Any advice? Thanks in advance! Cheers!

[Fred]

@hectorcruz wow that’s a lot of screens (roughly 20 HD). Honestly disguise is amazing and has a lot of real time flexibility, especially if you use notch, you can do anything you want and fast with a pretty amazing feature set. The director actor functions also mean you can control any number of machines from a single one and never really do any extra work. Getting this many unscaled pixels out of isadora will require a big painstaking process of synchronising patches across multiple machines (not just making the same file on each but imago je making smooth line movements across several machines and wanted a pixel perfect sweep along the whole 80m.

You could do this with isadora but getting just that spot on and tested would be tough, let alone anything more complex. This is the case with any software for that many pixels, you will need multiple machines. Choose something that supports this kind of topology out of the box. Vvvv can do it, and most of the big high end systems also have that kind of capability in the box. 

I recently did an installation with 12 projections and 300m of low density led screens with a similar resolution. I used multiple disguise servers and the whole things was pretty smooth. Syncing multiple machines for basic operating is what you will spend your time on if you use something that doesn’t have this capability, you won’t get a chance to make anything cool. Using software where this functionality has been made and rigorously field tested means you set it up and then make what you want. 

[mark_m]

@hectorcruz

I think the max size for a stage in Isadora is 8062px w x h, so you'd have to do some combining of stages.

I'm with @Fred in suggesting disguise.

You might be able to get the best of best worlds: use the disguise servers to manage all the hardware, stitch the wall together etc into one big canvas, and send an NDI feed from Isadora to d3 (the disguise software).  I did this recently, not on such a grand scale, but it meant I could use my lovely Isadora as a creative development tool.

[Fred]

@mark_m @HectorCruz this is an option, but moving that resolution of NDI will cripple all machines (or require multilple with sync issues from both the source and the NDI transmission), require a huge amount of bandwidth over the network, and be a big waste of resources. NDI needs to be encoded and decoded on the CPU, and disguise does all image mapping and processing on the GPU (isadora mostly too). This means all machines need to encode and decode a huge amount of data in order to change an interface. I also tried sending a massive NDI stream over a 10 gige network for my project and it dropped the framerate of everything, even when I put my application directly on the disguise machine so there was not real network transmission (this is a no no for disguise support, but it does accept spout now so technically you could try put isadora on the disguise machine - cringe). 

At any rate Disguise is very expensive (but this sounds like an expensive project). Unless there is real time interactivity I would look at some other workflows for sanity and budget restraint. Pretty much all LED wall processors take in an HDMI feed and the hardware captures the feed and controls the LED's. If your Isadora patch doesn’t have real time human interactivity then it is essentially playing video (even if it is generating it). 

If you do have interactivity in real time that is not optional (doubtful), have a look at Notch, it is actuall pretty easy and well integrated into Disguise. Disguise also has realyl well made connetions to unreal engine and proper network rendering pipeline as another option, this pipeline is designed to take the kind of resolution you are dealing with.

A cheaper option would be to render video of what you want using your favourite software (as long as it can output the huge resolution, or at least provide pixel accurate ways of rendering different parts of the whole frame one at a time (Isadora is not a great candidate). Once you have these videos and they are all aligned with the mapping used for the giant wall, just play them back from networked bright sign units. They will be in perfect sync and very cheap. Putting forward a proposal like this will likely give you very high quality results (you just need to be very careful about the mapping and how you render grab sections of the wall in the hardware drivers), it will also reduce your budget massively, meaning you could likely get well paid for your services, and if need be, hire others who are more adept at high end rendering suited for the task (like hours on after effects or fusion).

[fubbi]

In my opinion you could do it with a few mac studio ultras. 6x thunderbolt 4 plus 1 HDMI per unit. I recently used the m2 ultra with Isadora. 
4x Thunderbolt to to blackmagic HD converters (monitor 3G) and the hdmi output for the work monitor. I had a lot going on and Isadora never pushed 60% in the capacity monitor.

I did it with 15-20 trashcans and Isadora in 2013 and it was a pretty hairy affair, now it should be a whizz (the usual complexity of doing anything at scale, notwithstanding).

The controller unit (e.g. novastar sending unit) for the LED wall tells you a lot, its not unlikely that you can do 4k inputs. Then you need 10G thunderbolt converters, I think AJA.

Apple claims for the m2 ultra studio:

Five displays up to 6K at 60 Hz (or 4K at 144 Hz) over Thunderbolt, and one display up to 4K at 144 Hz over HDMI

So theoretically, 1x M2 Ultra nearly gets you there, a few of them synced would be comfortable.

Disclaimer, this is just roughly how I would approach it, whilst knowing nothing about you project.

Fubbi

[Armando]

@fubbi In 2015, in RIo de Janeiro, I did a video mapping installation with 18 hd projectors controlled by 3 mac laptops each mac with 2 triple head 2 go dp edition. SO each mac was spitting out 6 full hd images. Sync was done with netbroadcaster. I worked well. Sync over ethernet of course. CPU load was more than ok 40%id I remember well.

[Fred]

@armando @fubbi I have also done old school sync of video content with Isadora on multiple machines, and it worked a treat. It was cumbersome to setup, but not to hard and I ended up with frame sync stuff over multiple machines. Not the worst experience, but this was rendered video content.

The impression I got from OP @HectorCruz was that they wanted to use Isadora to generate video, not playback. The things that seem impossible or difficult to achieve over multiple machines and get continuity would be in this realm - not video playback (which is just standard annoying without an existing actor/director or boy grouping system. 

For example - if you had several machines how can you easily move a still image across the length of the whole screen - it is possible, but so much time is spent on making up for the fact that the system cannot do it by itself. Same issues for making a simple stripe that moved across all the length of the giant wall, possible but so much programming. 

Using particles with continuity would be impossible as the calculations in each instance on different machines would not match up.

Anything with any 3d content is almost impossible, or at any rate not worth the work, especially compared to systems that are built for this.

But @fubbi yes - 5* 4k is on the way (no control screen - remote interface), this is kind of unbelievable! It still only comes in at under half the resolution of the wall though, so you would either scale more than double, or go for 2 computers, manually program the sync and fudge some pixels. There is a hard limit on texture sizes, and these apply to virtual screens as well so you lose some of the easy outs for moving geometry around.

Things are getting there.

[Armando]

@fred said:

The impression I got from OP @HectorCruz was that they wanted to use Isadora to generate video, not playback. The things that seem impossible or difficult to achieve over multiple machines and get continuity would be in this realm - not video playback (which is just standard annoying without an existing actor/director or boy grouping system. 

 Ohh I didn't get that. Sorry. @HectorCruz"