Finding the Optimal OBS Settings for my Current Setup

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ahmadmanga7 hours ago3 min read

This is a follow-up of my

article, which I "researched" the info using AI. This time is about putting my knowledge in practice.

My Mini-PC with AMD Ryzen 7640HS APU has Hardware support for AV1 encoding. On OBS it's labeled as AMD AMF AV1 encoding. (Apparently, it stands for Advanced Media Framework.) I already decided to use this for my game recording, but I took hours of testing to finally decide on the specific settings.

First, I tried the VBR (Variable Bit-Rate) mode. Unlike the h264 encoding, AMF's VBR mode doesn't let you choose the Max bit rate, only the average. While I'm able to control the size of the file this way, and the result is always better than CBR (Constant Bit-Rate) mode, this mode wastes a lot of space in still scenes. If I reduced the average bit-rate, the quality of action scenes suffers.

So, I went to the QVBR mode, while it doesn't let me choose the average or max bit-rate, this mode allows me to choose an average quality level. First, I tested with CQ at 25. The result was great but recording at 1080p 30fps, sizes could reach above 4.5GB per hour.

CQ (Constant Quality) value tries to maintain the quality of the video regardless of how much bits in second. The lower value is the better quality, but the size gets bigger and bigger. Each encoder has different range of values for this, so they must be tested to know for sure. Zero would be completely lossless, but a value in the middle will still retain all visible-to-the-eye data.

I increased CQ to 27, then to 30. The quality, while lower, didn't get noticeably worse but the size did become a lot better! So, I'm going to stick to CQ at 30 for the current game, while going as low as 26 for games that need it.

Running with FSR

Once I used FSR to upscale my games, I realized that OBS doesn't record the upscaled footage, but the original footage before upscaling. I didn't like this because 900p isn't a standard for Youtube, and the video upscaler I found only upscales in multiples of 2x the size.

I did some research and I couldn't believe how easy the fix was: Display Capture -> Scale to Fit. Apparently OBS receives the final signal that goes to the screen, so despite I only need to set the output to size the FSR upscaled size and scale the Display Capture to it.

I also noticed that running OBS with Admin privileges reduces file sizes has become 20%-30% smaller, but I need to more testing to make sure that actually happens. It's just weird all my recordings are smaller in size after switching OBS to the administrator mode!

What do you think?