Video Buffer Demo (Composition by jersmi)

Author: jersmi
License: (unknown)
Date: 2010.07.05
Compatibility: 10.6
Required plugins:

Probably most useful for those somewhat new to Quartz Composer. This composition focuses on using the Queue patch to create a video buffer to capture frames of a movie then control playback.

There are other features, too: this is based on patches I use (and keep reworking) for live performance for movie playback and "analog-style" video feedback.

Note: this comp uses a third party plugin, v002 Gaussian Blur. It is inside the Video Feedback patch. It can be downloaded here: (Could also bypass it in the patch).

VideoBuffer_demo.qtz118.15 KB

.lov.'s picture
Re: Video Buffer Demo (Composition by jersmi)

For the video buffer, this plugin is a good choice - and probably better then to queue :) :

jersmi's picture
Re: Video Buffer Demo (Composition by jersmi)

That IS a good one. I didn't know about it... maybe I'll try posting a second version with this plugin included... still, need to queue to allow iterating sprite stacks with the Buffer with Z Depth patch.

At any rate, embarrassed to say I'm dealing with a crashy part of the comp I posted which I think might be in the Buffer with Z Depth patch. So beware anybody until I solve this issue -- go figure, the last part I added... :/

gtoledo3's picture
Re: Video Buffer Demo (Composition by jersmi)

Small note... you tag that as being my setup, which it is, but that randomize thing wasn't part of it - I'm not getting any crashing, but not being familiar with that part makes me curious. There's nothing fundamentally wrong, and you're even addressing converting to index before it hits the stop value, so I don't think that could be it...

If anyone is getting crashing, it's likely because the queue is flaky as %%**(&( and will QC will overload with it easily, especially when dealing with image structures. So, if your computer can't handle the data being thrown at the queue, it just crashes rather than grinding down in fps sometimes.

jersmi's picture
Re: Video Buffer Demo (Composition by jersmi)

Good to know, thanks for having a look, gt... just trying to give credit where credit is due... I've been playing with the randomize thing with the basic Queue / buffer patch without a hitch, but it's new to the Iterator setup like in the depth patch. Maybe I should yank the randomize from the Z Depth patch and post it up. The randomize effect can be nice, but the stack of sprites is the main point in that anyway.

gtoledo3's picture
Re: Video Buffer Demo (Composition by jersmi)

Yeah, for what it's worth, it was humming along for me - I tried it even longer... still no crashes.

I think you should likely consider having the queue size smaller for people, and maybe adding something that can limit the pixel w/h before it hits the queue. That way, people with less powerful computers have less of a chance of it going into a spasm.