Video Scratching

scalf's picture

I am looking for a good way to "scratch video" in QC. By scratch, I mean analogous to Dj scratching in that one can alter the speed, position, and direction of a video on the fly using some fader, rotary, or other controller.

I have looked around, and it seems as though dust made it pretty good with his approach but I found no file to dive into. http://kineme.net/forum/Programming/bestapproachtovideoscratchplugin

The internet hints at using some sort of queue system to drive the video's position from what I have gathered.

Of course, if I hook up the mouse input to the rate, or selection start, the video becomes choppy. I know there is a good way to do this.

If someone could point me in the right direction that would be much appreciated

Best Video Playback Codec

scalf's picture

I have been using Quartz extensively for playing back loops, adding effects, etc, and I was wondering what the fastest video coedc would be for playback in Quartz Composer?

The clips are usually played at 720, but that may be irrelevant. I have been using video programs, so converting them to any codec is not the problem, but there are so many options I was not sure which would be the most tailored to QC - H.264, ProRes, etc

OSC Web Dance 3 (Composition by Prack)

Author: Prack
License: Creative Commons Attribution-NonCommercial
Date: 2012.01.05
Compatibility: 10.5, 10.6
Required plugins:
Audio Tools, gl tools, qcOSC

OSC Web Dance 3 by PrackVJ aka Marcos Prack www.iprack.com

With this comp you can control a differents meshes. You can rotate, change colors, and make some funny things. You need an IPod Touch, or an IPad running TouchOSC app, and some more things.

You need to download the zip file, they have the .dae files, a readme file and the TouchOSC files.

You need to install some patches from Kineme: the Kineme Audio Tools and the Kineme GL Tools. Additionally you need to install the Hexler's qcOSC plugin, you can found it at


This is an excersise I made for my vjing session, you can use it, and modify it as you want. You can change the .dae files if you like too.

If you have any question you can write me to:

mprack at gmail dot com

I'm not an expert, so, the composition could be better, if you can improve it, please, send me your file, I like to learn from you. Thanks a lot, and thanks to the QC community.


16 Pad Visual Mixing Environment (Composition by scalf)

Author: scalf
License: (unknown)
Date: 2011.04.15
Compatibility: 10.6
Required plugins:

A friend and I recently threw a Flash Rave in a effort to raise money for Japan. All went well and it was successful in every way.

That being said, I made myself a 16 pad visual mixer with Tryplex's toolkit. You use one hand to choose the visual and the other can "bounce" to the music. This way there is no timing, sliders, or controls to muck with. All you have to do is select/switch between the visuals and jam to the music with the other hand and the visuals will follow suit!

I would like to say thanks to Tryplex for all the great work (http://code.google.com/p/tryplex/)

And also to Gtoledo and Zugakousaku for some of their compositions which I have learned from greatly in the past while!

have fun!

mapping festival

dust's picture

so just a headz up to anybody in the land of swiss or geneva. there is a pretty cool festival i have some of my quartz composer work. here is a link. i thought some vj's in europe might find this interesting.


you will see my piece is projected on ice blocks. basically one of my professors had got in a car accident and has got brain damage, so i have been working with help helping get his memory etc back... so his idea for the piece was originally to be 4 sided projected on a block of ice.

now there seems to be a shortage of ice in switzerland ???? so now its a two sided piece as switzerland exports their ice to china or something ??? to get a cubed wall of ice in switzerland i guess costs 4k or something and is sent from new england in america. so right now we are trying to construct an alternative.

but the basic idea was to have mri - cat scans and angiograms projected on the 3 sides of the ice to represent the brain loss of memory etc.. then in the front we are projecting a quartz file that has a video of my professor telling his story. in another room there is a camera where people tell their memories and their images and audio get intertwined with original story and sent out to the projected art piece.

the tech is qc, max, and opencv. open cv is to detect when someone is present telling a memory to the camera and snaps image fragments and audio samples that get over layed with each other.

im not sure how it will turn out as it was basically thrown together in one night. but the idea to have all these randomized sequences of audio samples in different languages as well as image samples is pretty powerful in concept. we will have to see in implementation.

has anyone else ever projected on to ice or done anything similar to this in respects to av randomizations etc.. im still getting used to randomized art.

here is a pic of the qc file. so yeah just wanted to give anybody in the land of swiss a heads up etc...

you will have to let me know how this turns out as i'm remote conference to switzerland. im a little worried hopefully we will be able to sort out the ice.