Greyscale ImageBuffer

M.Oostrik's picture

Hi All

I'm using the queue patch to create a video buffer. For most of my installations I use black and white (infrared) video from my flea2. The dimensions of the video are 1280x960 and it runs @ 30 fps.

When I use the image as is I can store up to 1000 images before strange things start to happen (flickering frame drops etc). I quess because most of the video Ram is used (?).

Because I use black and white video it din't seem logical to use the image as is in QC, because the image is RGBA (is this right?).

I started looking into alternatives and decided to try out the QC image to CV image (from Kineme CV) before the queue patch and CV to QC after. This resulted in a stunning amount of 20.000 images before QC fps start to fall under 30. Up to 35.000 (and counting while i write) images it runs @ 20 fps.

I got one problem here. The image turns from Black and White into Blue and White. I can solve this by inserting a Render in Image patch or an Image Resizer patch after the Video in patch or try to restore the black and white with a False Color patch. All these solutions bring down fps by around 30% .

2 concrete questions. is there a solution for the blue problem? anybody got suggestions for a different method of converting the images to greyscale?

I'll try the same patch on my Hackintosh with a GTS 250 graphics card when i find the max images on my MacPro with Ati Radeon X1900.

regards Matthias

Time Smear

dwskau's picture

These are real-time versions of some time smear effects. On a brand new MBP they run best at around 24 iterations. If anyone has any suggestions to improve performance and get more iterations, I would love to hear them.

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: http://v002.info/?page_id=6 (Could also bypass it in the patch).

Structure with brackets and structure ( ) with quotation marks " "

akaioni's picture


I have a small problem that I cannot figure my way around, I am trying to send some numbers with Kineme's ArtDMX, it works well when the structure is supplied by one of Kineme's Structure Maker, but when I aim to get the structure from any of the Queue patches. The only difference between the two structures is that one has index number written in quotation marks and the others in brackets.

I am now wondering, is the root of the problem that ArtDMX does not want to digest the data because of brackets, how should I avoid it.

I'm posting the screen shots of the patch.

Note Spiral (Composition by gtoledo3)

Author: gtoledo3
License: (unknown)
Date: 2009.12.09
Compatibility: 10.5, 10.6
Required plugins:

This is an example that uses particle systems, the queue, and iteration to make a kind of image snake/spiral effect. Audio triggers an image "chase".

The attached composition doesn't have all of the source images of the video clip below, but it is the same basic qtz. One can attach more images to the multiplexer/particle system in the render in image, and add to the chase effect.

Alpha blending on the sprite inside the iterator can also be favorable, but I've left it in Over mode for this example.