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And what times are actually reasonable?

My situation: I edit videos using Blender for a Youtuber that has just purchased a greenscreen. I like Blender because I already know how to do all the things I need to do, and have zero experience with any other similar programs.

However, for the newest video, rendering to PNG in RGBa is going to take about 10 days for a 10 minute greenscreen video (~35000 frames). Many of our videos are longer than this.

This seems like an absurd amount of time, so I rented an AWS server thinking it would be a magic speed solution. So far though I have been unable to be approved for a multiple GPU server, so my home computer (1080ti with 16GB memory) is still faster at about 20 seconds per frame.

So I guess my question is two-fold:

  1. Are these times normal/reasonable for this type of compositing/rendering?
  2. Is this a Blender problem? The video creator often balks at my blender "it takes this long" stories and is convinced that if only I would pay for a better program, then everything would be amazing and fast. Is he right? Please tell me he's not right. Unless he is. I guess.

Extra info: I did try a few scripts for forcing Blender to utilize all of the cores of my PC, and one of them finally worked. However, the relevant add-on sidebar doesn't seem to be available for the Compositor, only for the VSE. In the compositor I have to use the normal Render-> Render Animation option. Also, I'm not sure if I should even be using the core script add-on, or if I should just be using my GPU normally, since I do have it set to CUDA in the options and have a decent GPU.

Task details: I am sent a split screen 3840x1080 .mkv with webcam/greenscreen on one side, and screen output on the other. I split off the webcam side as a 1920x1080, make the greenscreen disappear using the compositor, then spit it out as PNG frames so I can overlay the creator/webcam footage over his screen output footage. (This is my first time doing this and I just did it the only way I could figure out how, feel free to tell me I'm doing something wrong and stupid.)

Also: Wooot! Finally just got the email that AWS approved me for the 8 GPU instance. Really curious to see how much faster it goes. Question part 3: Is it weird to rent something like that for projects like this? I just couldn't see taking 10 days every time I need to edit a video. It's like $7/hr though, which the creator is okay with paying assuming times are reasonable. EDIT: Turns out 8 GPUs on a P2.x8large instance gets it down to 8s per frame, compared to about 18s per frame with my 1080ti at home. Def an improvement but it will still take 3 days, and @7/hr. This can't be standard, right? This video is under 10 minutes long.

Swerve
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    https://blender.stackexchange.com/questions/148231/what-image-format-encodes-the-fastest-or-at-least-faster-png-is-too-slow might be interesting. It's hard to talk about the issue without knowing what specifically you are rendering. – Martynas Žiemys Jan 13 '21 at 08:44
  • Thanks, I added a little more info in the post.

    I'm not really familiar with much more than the basic tasks I've done with the VSE so far, or the benefits of various output types; I thought PNG was just what you had to render to to use an Alpha channel. Maybe I'll check out the OpenEXR thing.

     – Swerve Jan 13 '21 at 09:01
  • Hmm, not sure if anyone will find this useful, but on my computer both Open EXR and OEXR Multilayer options not only take almost 2x as long to render each frame as PNG did, but the transparency is no longer working properly as well. Still using RGBA but in the .exr's I can see the greenscreen as a brownscreen in the background. Outputting to PNG with no other changes have perfect transparency, for whatever reason. – Swerve Jan 13 '21 at 09:17
  • Why use blender when there are much better alternatives to edit video nowadays? Try davinci resolve. 10 days to render is not a reasonable time. Blender is a wonderful 3d app, but the video editor is not an efficient tool. – susu Jan 13 '21 at 12:52
  • Because I didn't know the difference, I guess. I tried Resolve when I first started this stuff, but I couldn't get it to work properly on my LInux machine. It wouldn't recognize the videos and it wouldn't exit full screen mode when open (HUGE dealbreaker). So I tried Blender instead. At this point it's just convenient and easy to keep using since I'm familiar with it. Until now rendering time hasn't really been a big enough issue with short videos. But I guess I have an answer. Which means I probably have to buy Adobe products. Which... kind of sucks. – Swerve Jan 13 '21 at 13:07

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