Today I tested out a new SVP profile with a 120 Hz refresh rate, comparing a 24 fps source to a 30 fps source. The 30 fps source still experiences judder when set to a x4 (120 fps) integer ratio. Interestingly, the 24 fps source played smoothly at x5 (120 fps) and x6 (144 fps) integer ratios.
Previously I thought that the 1080p resolution was impacting SVP performance, but I think this was merely a coincidence. As it turns out, both high res and low res sources with a 24 fps framerate are playing smoothly.
Doing further digging, I found out that not all of my 30 fps sources exhibited juddering. In one comparison, I noticed that a 30 fps anime trailer juddered, but a 30 fps video game trailer did not. This leads me to believe that this judder may be caused by how some anime on the internet is encoded. Since anime is produced at 24 fps, and this source material is encoded to a constant 30 fps framerate (for some reason), I believe this causes imperfections which are masked by motion blur, but is made more obvious when frame interpolation is applied.
On another note, some of my judder consistently occurred at the same time regardless of the source, but I think I figured out the cause of that too. Usually, I have SVP OSD messages disabled, but after enabling them to troubleshoot what was going on, I found out that two judders happened at the same time as two of the SVP OSD messaged. The first judder occurred as SVP was resizing the source video, and the second occurred during black bar detection. After disabling black bar detection and frame size alteration, both of these judders stopped happening.
> > dropped frames 0
> What pan & scan judder do you see?
> The video must move flawless.
I forgot to mention that I refreshed the madVR statistic (Ctrl+r) in the middle of playback. Since the dropped frames (~20 - 35) only occurred at the beginning (due to screen resizing and black bar detection), I didn't think it was relevant to typical playback performance. Of course, I was just ignoring an underlying problem, but that's my fault.
I'm still experiencing dropped frames at the beginning of video playback (~5 - 9), but I haven't got a good explanation for why that's still happening. I think that since I have madVR set to delay playback until the render queue is full, it could be dropping frames until the queue is full. Best guess I've got so far.
All and all, I think the main cause of my judder issues were caused by poor encodes of anime. Thanks for helping me narrow it down, SVP is working much better for me now!
