Question / Help can't get smooth videos at 48 or 60FPS

[sneak]

I'm really happy that OBS now supports NVENC and I'm trying to use it to stream and record at the same time. I've been testing the recording part only and can't seem to get a smooth video if I use 48 or 60FPS. I'm using OBS Studio 0.14.1 and capturing the game with game capture mode. While playing, CPU usage for the game is no more than 44% and for OBS it's no more than 2.2% with total GPU usage at 60-80% and VRAM usage at 55%.

These are my settings:

• Recording Format: mp4
• NVENC H.264
• Rescale: 1920x1080 (native 2560x1440)
• Bitrate: 10000 (tried 25000)
• Keyframe: 0
• Preset: Default, High Quality, Bluray
• Profile: main
• Level: auto
• [x] Use Two-pass Encoding
• [ ] Use CBR
• GPU: 0
• Audio Bitrate: 160
• Audio Sample Rate: 44.1khz
• Audio Channels: Stereo
• Base (Canvas) Resolution: 2560x1440
• Output (Scaled) Resolution: 1920x1080
• Downscale Filter: Bicubic
• FPS: 48, 60
• Renderer: D3D11
• Video Adapter: (blank)
• Color Format: NV12
• YUV Color Space: 601
• YUV Color Range: Partial

My first choice for preset was Bluray, then I tired High Quality then Default. They all give the same result. A video that is choppy, like frames are being dropped. Here's an example:

The FPS is low when you first tab back into this game, it has nothing to do with the system/OBS. After that you can see the in-game FPS increases to 200+.

My specs:

• i7-3770k (h100i)
• EVGA GTX780Ti Classified 3GB ACX Dual Bios
• 2x 8GB Crucial Ballistix VLP 1600Mhz 9-9-9-24
• SeaSonic SS-650KM Gold
• Game on Samsung 840 Pro
• Recordings going to Western Digital Caviar Blue
• Windodws 8.1 x64

It looks like this is the indication of the problem:

20:43:38.000: Output 'adv_file_output': Number of skipped frames due to encoding lag: 761 (61.3%)
20:43:38.000: Output 'adv_file_output': Number of lagged frames due to rendering lag/stalls: 12 (1.0%)

However, I don't understand why this would happen based on my hardware and these settings.

I've included the logfile.

 

[Bandock]

From what I read in other threads and my own testing after reading through such thread, your best bet is to turn off two-pass encoding. It definitely makes it run slower (not meant for live recordings), though very likely to increase quality.

 

[sneak]

From what I read in other threads and my own testing after reading through such thread, your best bet is to turn off two-pass encoding. It definitely makes it run slower (not meant for live recordings), though very likely to increase quality.

Thanks so much. This solved the problem. So I should leave two-pass encoding enabled for streaming? It seems I can't have a separate stream FPS from my recordings, so I would be streaming at 1080p60 and recording at 1080p60.

 

[Bandock]

You're welcome. I would probably leave it off for streaming as well. Two-pass encoding is normally used on footage that has already been recorded.

 

[sneak]

As I thought, but since it was on by default in OBS it made me reconsider the possibility there's a reason for it.