how can I take an mp4 that is basically a rotational red channel (that mimics my attempt at a vinyl record revolution) and use Analyze CHOP and Top To CHOP to rotate or translate a piece of 3D geometry in a scene (such as a Box SOP or a Grid SOP)?
screen_grab_top.2.toe (4.63 KB)
screen_grab_top_movie_prep.mp4 (5.1 MB)
I may also be asking the famed question, how can I swap the x and y axes in the CHOPs? I saw some computer diagram on how to do it with computer hardware but I’m not an engineer by any means of the imagination, so I couldn’t even decipher the diagram if I wanted to.
How can this be done with Touch’s toolset?
Thanks in advance.
Well, you can use info chop with your movie in from there you can retrieve channels corresponding to current frame and total frames. Then you can use this channels to drive your animation. Something like frame 0 = box rotation 0 degrees and frame (last) = box rotation 359 degrees.
that doesnt seem to work very well. especially if my movie is not a constant rotation. that mp4 was just a sample with constant rotation. but in my case i would be generating the movie in from a screen grab of a serato video scratching a record. there is a constant high speed fluctuation of the red arm. i found that using a chroma key top after the analyze top not chop is good to get cleaner results from the alpha channel. but i still dont know what to do with the resultant graph.
thanks for your response by the way and hopefully you have some more ideas…
maybe there is a way to get a midi information from serato? Or a timecode information? There are midi in and LTC chop for it
no from serato. that is why i initially tried to use a midi turntable with no success. i have an extensive post about that as well both here and on the sidefx houdini forum if you want to take a look.
This is the thread:
[url]Houdini Area CHOP (?) equivalent - Beginners - TouchDesigner forum
You will see a link to the sidefx forum as well. There I have posted some graphs from CHOPs in Houdini. The problem I had with the MIDI turntable is that the peaks and valleys of the record movement did not seem to correspond with reality. However it could be that I didn’t connect the proper nodes in the network to get the results that I needed to get.
If you can solve that for me then I still have use for my MIDI turntable. Otherwise I would like to analyze a Screen Grab or Movie In which mimics the turntable platter rotation as it scratches (using Serato’s video output) and then be able to transform geometry and do other timed events from that.