Record framebuffer OpenGL\C++

Dark Light · 26 Feb 2015 at 00:05

I am wanting to record what my OpenGL program renders in a lossless format (as it is simple objects without lighting for a video). I would prefer to use an existing library, although I am able to implement one myself if need be. The only constraint is really the file size, I don't need it to be massively efficient, but I am wanting to upload the video (12 hours) to YouTube and there is a 128GB file size limit. Will be rendering it at 4k at 60 fps, although if possible would like to go higher (for better animation etc.) if the reader time and file size allows.

NickK · 26 Feb 2015 at 08:31

Hmm.. I think you'd answered your own question regarding using youtube.

Next ISPs: Most people don't have 4k available nor a service provider that will deliver 128GB of video (remember most have caps in the tens of GB).

Is there any reason to render for 4K? I doubt many people have that capability.

Dark Light · 26 Feb 2015 at 08:57

NickK said:
Hmm.. I think you'd answered your own question regarding using youtube.

Next ISPs: Most people don't have 4k available nor a service provider that will deliver 128GB of video (remember most have caps in the tens of GB).

Is there any reason to render for 4K? I doubt many people have that capability.

How have I answered my own question? And what does an isp cap have to do with anything? I am wanting to use the program only for my own use and thinking of 4k just because why not, you don't need a 4k display to render at 4k.

mid_gen · 26 Feb 2015 at 10:32

Not sure what you're asking....if it's your code, just dump the framebuffer out to an image format of your choice, then convert to video?

Dark Light · 26 Feb 2015 at 22:46

mid_gen said:
Not sure what you're asking....if it's your code, just dump the framebuffer out to an image format of your choice, then convert to video?

The images would be too large, I am wanting to have the program output a video file. So I want to give the framebuffer to the code that encodes each image to the next frame in a lossless format, as to save space and so that there is no artifacts in the video.

mid_gen · 27 Feb 2015 at 09:28

At some point you have to handle each frame.....at 4k 60fps lossless I'd be surprised if you're going to be able to do encode in realtime without some fancy kit.

Do it in chunks if you don't have the space to dump them all out in one go?

D.P. · 27 Feb 2015 at 15:42

Just save the frames as images. If the scene is simple then save as a loseless compressed PNG. Then use whatever software you want to convert to video.

But really, you need to think if you really want 4K at 60 FPS out of this. Almost no one has the capability to view it and I doubt it is interesting enough to warrant 12 hours of 4K.