60 FPS in Video ist actual 59.49 FPS in record

Hi,

Okay I just figured out a thing that was smashing my brain for a while.

I record lossless crf=0 in 2560x1440@60fps

In Adobe Premiere the video was often very choppy, espacially with games with high motion an graphics (like The Forest)

I always thought my pc was not fast enough for premiere, so i bough a new cpu (i7-4790K)

But still Premiere only gets out 1 fps on some parts of the video.

I use a tool to check the bitrate of a video and TODAY i saw something strange (see screenshots)
all game recordings that are marked as 60FPS are actual 59.49 fps while desktop recordings (Display Capture) are 60 FPS (as long as you dont play a game)

I first though this was the fault of Bitrate viewer showing wrong fps, BUT when i changed the fps of the video in premiere (how to handle the file) from 60 to 59.49 it runs smooth. No more choppy.

So for me, it seems the recording is really 59.49 fps - how can that be?

My Monitor is a Dell U2515Hc and running 256x1440@60hz (The OSD says 60hz but windows says it has 59hz)
Can this cause this effect?

Any idears to force 60fps?
 

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Black Ops

Member
Enable CFR to maintain 60fps

Why would you even use CRF0? The output file is insanely large and editing software doesn't like that CRF

If you want no perceived visual Loss in quality, CRF 14-15 is sufficient.
 
It is CFR
and i want lossless because i want to reduce multiple encodings
lossless workflow: record (lossles) -> premiere -> frameserver -> render ( megui, crf15) -> then youtube does encode again (vp9)

if you record lossy you lose quality in one more step again.
 

NalaNosivad

Member
Do you have access to ffmpeg? If so, can you post the output of:

ffprobe -v quiet -print_format json -show_format -show_streams yourfilehere.mp4

for both files? I'm curious to see what ffmpeg reports.
 
Here you go.

it's funny if i set 30, 50 or 61 Bitrate Viewer always shows the correct fps, only with 60fps it detects 59.94
 

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yes Bitrate Viewer detects 59.94 on this file
heres media info.
ffmpeg and media info both say 60fps as well as Premiere (i think Premiere just reads the header or something)
 

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the funny is i just would say this is cause by rounding error in Bitrate Viewer,
AND if i do a Desktop recording with the same settings, Bitrate Viewer detects 60 fps
and if i switch in Premiere form 60 to 59.94 the playback is smooth
 
This are files from a Desktop recording, where Bitrate Viewer says 60FPS
 

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Okay, if i have both on my scene, desktop AND Game Capture where game capture lays OVER desktop capture and start recording while im on the desktop and then switching to the game, it is also 60fps in Bitrate Viewer.
 

NalaNosivad

Member
Could you try using the custom ffmpeg output and capture to ffvhuff or something other than H.264? I'm honestly clueless so far, but it would be interesting to see if the problem occurred with different codecs and containers. Might help others narrow down wherever the problem's occurring!
 
okay i did it.
custom ffmpeg ouput as avi with ffvhuff and pcm_s16le
seems to be ok Bitrate Viewer Reports 60fps.

i will test custom ffmpeg with mp4 x264 and aac (but now really tomorrow) :)

are you an obs developer?
 
okay i used custom ffmpeg with
preset=ultrafast crf=0 profile=high444 keyint=60
and mp4 container and the result is again 59.94 fps
 

VanDuits

Member
It´s just an idea. If i´m using a DVI cable, then I can setup Assetto Corsa to 60Hz in fullscreen. But if i´m using a HDMI cable, then i can run 59.94Hz only.
Which cable are you using? like i said, just an idea...
 
yes im using hdmi.
my monitor has only hdmi and siplay port. i'll check it, but i've already set the monitor hz to 60 and so effect
 

NalaNosivad

Member
okay i did it.
custom ffmpeg ouput as avi with ffvhuff and pcm_s16le
seems to be ok Bitrate Viewer Reports 60fps.

i will test custom ffmpeg with mp4 x264 and aac (but now really tomorrow) :)

are you an obs developer?
I'm definitely not an OBS developer, no!

I'm curious to see whether I have the same problem in Premiere Pro though, to rule out the tool you're using that reports the frame rate as 59.49 as being at fault (given both ffprobe and MediaInfo report 60fps).

Could you upload two raw sample files to the Dropbox link I'll PM you after I post this? One that tool reports as 59.49 that's stuttery with Premiere, and another that's reported as 60fps and is fine with Premiere? Either that, or upload it to your own and post the link here. Either or!

I'm just really curious to see if I have the same problem myself.
 
i made a recording with bandicam, it's not choppy and sais 60 fps (without the ntsc) and also i rendered a file with premiere, again it's 60 and no ntsc - so i thinks there's something wrong with the obs settings.

im searching the ffmpeg docs for parameters, but no success, yet.

i can do an upload, but it will take a while
 
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