and now that i think about it. even if Houdini would work, if i launch BOME first to initially capture the Rane MIDI signal and then launch Serato to try to also secondly, it still might not work as BOME has captured control of the Twelve first and exclusively. but i will try in a few hours just to rule out the off chance.

Hi.

I have posted about my developments with MIDI In as it relates to Denon SC3900 Media Turntables long ago. Specifically I was able to use the 2 outputs from the Denon to have one read into Serato and the other read into Houdini, effectively allowing me to scratch on the turntable and have the audio go to Serato and the 3D Geometry in Houdini to follow the action of the scratch in an animated fashion.

I now have Rane Twelve turntables and they are MIDI HID Devices. They only have one output altogether: MIDI over USB.

I am wondering if there is a way for me to block the MIDI signal coming from the Ranes (perhaps on a per-channel basis or otherwise) so that I can read the internal MIDI in Serato and also read the signal in Houdini via BOME MIDI Translator Pro. The BOME Translator would hopefully read the MIDI from the turntable and pass that signal on a different channel to Houdini. I am not sure if this would work, though because once Serato captures the MIDI signal, it might prevent BOME from receiving any input whatsoever.

Unfortunately I cannot pass the MIDI from the BOME Translator to Serato as this will not allow for the scratching of the platter to be read as it would be with the Rane Signal directly. Somehow the Ranes and Serato have an inseparable communication or marriage so to speak. If I run BOME first then launch Serato, Serato won't read the Ranes and I cannot scratch audio with them.

In the past it worked only with the Denons as I could pass the Serato TimeCode signal over the RCA plugs to my Serato mixer while passing the MIDI over USB to the BOME Translator which would pass the signal to Houdini.

Any help on this is appreciated and I apologize for being so verbose in my initial message.

and thanks for the last info on “Frame”

it is rendering at 10 frames per 39 seconds whereas before each individual frame was taking over 1 minute to render a single bgeo file. and there is more data in these new frames as well as I have selected a slightly different set of color ranges and deleted based on the new group expression. i thank you immensely for your help! blackpixel and tamte

ok i got it!! i had tried to place the path string directly into the vex expression but i see you need to use “map” and place the path into the parameter interface separately. in H13 there is no quick shortcut button to create parameters based on ch strings in the expression. so i had to click the gear icon.

oddly enough i just tried using one of the methods with an attribute wrangle in H13 and it fails unless I am doing something wrong, which is also likely. the grid shows up white instead of with the texture.

i see $F still works but i think it is important to know how to use “frame”

wow! yes, it works! i will let you know how fast it is in comparison when i try to apply the 7000 animated texture frames. I was using “$F” in the name of the textures. how is this done now with the “@frame” call?

but you're right i think it will cook faster if this method would work.

Hi. unfortunately this doesn't work as i cannot group the primitives after applying the attribute. the texture from the attribute wrangle is not baked in. zero primitives are grouped.


I have shown the way I use the Primitive SOP to apply the texture and the red from the Houdini logo is somewhat orange showing the yellow grouping interaction with the colors of the logo.

blackpixel
1. Pre-render the whole thing in low resolution, and low settings so it outputs the attribute you want to use as a mask.
Then project UVs from the camera back onto the geometry and use the rendering as a texture in a PointSOP / Wrangle.

hi and thank you for your response with some ideas. I am actually doing something like this. I am using a “tex()” expression in a Primitive SOP to read the colors of the texture directly onto the Primitives of the Grid. However the geometry of the primitive has to be so dense in order to read the colors accurately (I am using a screen recording and need to capture info from the recording/animated material as geometry based on colors, if that makes sense), but because it is so dense this method takes eons to cook. I have over 7000 frames of animated material/texture to read and process in a ROP output and it has taken over 24 hours so far and is only 60 percent done rendering. I am not even sure if the geometry in my ROP will work for what I would like. This is why I was hoping to magically convert the texture to point or prim colors easily.

Unfortunately I would also have to search deep for some tuts on how to use a Point Wrangle the way you describe with uv's. I have seen some of Rohan Dalvi's tuts and hope to be able to find more. Houdini is harder than it was before Attributes/VEX became the mainstay of workflows.

Hello. Yes, I have had a license for many years but continue to learn. I am still using H13 but this may also apply to principled shaders in H18.

What I would like to do is take a Material that is rendered across thousands of frames (animated material) and convert that into Primitive Colors or Point Colors so that I can group them according to an expression, grouping only the colors of the primitives or points that I desire, deleting most of the unneeded geometry. The material is currently placed after a UV Project SOP and applied with a Material SOP.

How can I do this? I tried searching and found a post that seemed to ask for the reverse either here or on odforce though I didn't quite understand the workflow in the post.

Any help is greatly appreciated. Thanks, Rene

hi srletak76,

here is a file i just edited to share in this forum. it took a bit of me searching to find it as i had not appropriately named the file to relocate it in the future, lol.

i have tried to name the chopnet (you should view chopnet2) as self explanatory in the node names as possible. however if you have questions on what i am doing, i can explain things along the way. i did not create that many sticky notes and explanations in the file themselves, just the nodes.

thank you mestela

replying so i can sub this topic

i know my version of Houdini is ancient but you can do the same thing in Houdini 18 I believe, though I have noticed that there is a slight delay in playing back audio on the timeline in CHOPs in the latest version.

hello. I would like to begin this post with a link to my latest Vimeo contribution which is an unfinished video. at the end of the video around the 30 minute mark i display a Manual Scratch and and Automated Scratch, the latter of which I did with CHOPs in Houdini Fx 13.

https://vimeo.com/406558118 [vimeo.com]

I also have a SoundCloud Post wherein I did a test in a 1 minute long audio file. the file gets progressively more complex from emulating what human DJs can do until the point where Houdini supersedes human scratch capabilities.

https://soundcloud.com/realdjthink/airplane-window-track-22-test-scratch-automation?in=realdjthink/sets/a-view-from-an-airplane-window [soundcloud.com]

….

Now to the heart of the post: I have a tutorial or demo of sorts on my YouTube channel here:

https://youtu.be/Tm_ql0KySiQ [youtu.be]

It is a demo of a Vinyl Scratch Template method in CHOPs in Houdini 13 wherein you can take a scratch pattern made from digital turntable that has a MIDI platter (I used the Denon SC3900 although you can use the Denon SC5000M or SC6000M) that Houdini can read the MIDI information from, and then replace the audio that you scratched with a brand new audio, even one that hasn't yet been recorded but might be recorded in the future and imported into the CHOPs network. Please watch the entire demo video if you are interested in DJ methods and Hip-Hop music. Houdini is such a vast tool and I am so happy that it can process audio.

The caveat to my technique in the demo is that the replaced audio does not simulate the original record scratch that you hear in Serato when recording the MIDI data into Houdini 100 percent. instead it tries its best to sound close. But that might have more to do with my lack of mastery of Houdini and I am hoping anyone who knows CHOPs well can interject here and lend some guidance as to how to replicate the vinyl scratch sound using the Time Warp CHOP as I have done or some other method which will yield better results than what I was able to do so far. In any case the first stuff I mentioned all the way at the top was also done with Time Warp I believe, utilizing a Wave CHOP or Waveform CHOP (I get those confused) and manipulating the default Sine Wave until I get an interesting scratch sound out of it. Thank goodness for Houdini CHOPs being able to save WAV data using the right-click context menu.

Thanks for reading this post and I hope I have helped someone. René Toussaint / DJ TH!NK (markerline)

Wow! That works very well! I'm surprised I never knew about this CHOP before. Thanks for the lesson!

Attached is the working file.

Hello Community:

I have used a MIDI turntable and MIDI mixer to create a procedural network for turntable scratches with the ability to substitute any audio sound in the original audio's place and create a new sound with the same scratch pattern.

In essence it utilizes the MIDI data from the platter rotation of the turntable and the fader movement from the mixer to drive a Warp CHOP as well as a Math CHOP (fader cuts the sound at zero-values). Using this same Warp CHOP one can place any audio into the network and thus work with a Scratch Template.

The only problem is that it is not completely procedural. The audio has to get trimmed and shifted on a per-audio basis each time a new source is defined.

If anyone has any ideas on how to improve the CHOP network, please offer suggestions in this thread. I will attach a file in the next post if the file size limitation permits.

-markerline