I'm getting this error when I try the sample patch for gemframebuffer. I checked and my graphics card supports openGL 1.3. By the way, the graphics card is XGI Volari V3.

Any idea what's going on? Does the example patch work for anyone?

Let me start off by saying that I know that there are many threads on this already, however, I still haven't figured out a good way to do this.

So I have a gem video that is driven by a lot "real-time" midi data. I play the midi "live" through a DAW, but I can generate a midi file for it (it's not really live).

Now I want to record the video, and I've tried all the above methods and nothing quite works. pix_write gives a horrible frame rate. Plus it seems to skip frames randomly. Same with screen capture software. I never got pix_record to work either.

It's been suggested in other threads that one can record the live actions and then do the rendering offline. I guess the logical way to do this is to play a midi file in pd and use pix_write. I have no idea how to play a midi file in pd. Any help would be appreciated.

By the way, I'm on Windows.

Thanks!

Hi guys, I'm very new to PD and GEM, but started playing around with it. One thing I want to do is to experiment with different blend effects. Playing around with alpha is relatively easy, but I want more sophisticated blending like multiply and screen. Has anyone tried to do this? I tried calling an OpenGL function, GEMglBlendFunc by attaching it to gemhead but nothing happened. I called GEMglEnable with the right GLdefiine as well. I don't have the patch file on me right now, but I'll try to upload it once I get hold of it. If anyone has a sample patch that can show me how to do this, that would be great.

By the way, I know that it's possible to do this using the pix_ objects, i.e. pix_multiply, etc. But I want to apply the effect to the whole schene with 3D objects that are moving.

If everything fails, I think I'll have to learn a bit more of OpenGL and maybe try it in C++ first and then translate it into pd.

Thanks!

Thank you for the kind words I can't believe it's been almost exactly one year since I last looked into this! Regardless of whether you're using a Mac or a PC, I think the same idea applies. You need to somehow record your live actions, and then "replay" them in the same processor. Any midi software should allow you to record live data from a midi device (this may even be possible with pd). Then once you save that into a midi file, you would have to replay it in your patch where gem is running. You can then trigger pix_write every 40 milliseconds or so. Pd's concept of time is virtual, and everything will run much slower, but will appear in sync because both the screen snapping and the replay of the midi file will be slowed down equally.

Unfortunately I can't provide much more info because I haven't look at Pd in a long time. But hopefully, this will steer you in the right direction. Good luck and don't give up!

Alright, finally got everything working. This was unnecessarily hard. Exported the track into midi. Created my own notein_sim and used pix_write to render the jpegs. Used a free program called PhotoLapse to convert the jpegs into avi and then combined the sound and the visuals in MovieMaker. This required a lot of trial and error, but--hey--it worked

Final product:

slvmchn, I think external recording is definitely an option. Of course one would need a good video card that is capable of digital output (DVI, HDMI, or something like that).

I don't really care for sound because I only use pd for the visuals. The approach I'm currently exploring is offline rendering with pix_write. I'm exporting my score as a midi file and then loading it using [ midifile ]. This is still work in progress but it seems doable. One thing I'm concerned about is getting the timing right.

In terms of converting jpegs to a movie file, I'm not sure why you had to jump through hoops. VirtualDub can do this easily for you.

I'll report back once I have something working.

I've tried CamStudio. It works, but it gives a pretty bad frame rate. And my video is not even that complicated. My PC is a few years old, so maybe it's time to upgrade.

So I guess, the common practice is to use video capture software?

I'll try a few optimizations, but it just feels wrong to use video capture for this.