Flowframes 1.38 is coming soon, and there will be a game-changing new addition: VapourSynth-RIFE-ncnn-Vulkan has been integrated (called RIFE-NCNN-VS in Flowframes). This means you can interpolate videos without the need for frame extraction, frame saving, and separate encoding. With RIFE-NCNN-VS, everything is done on the fly in RAM - The video is decoded, interpolated, and encoded, and nothing needs to be written to your disk except for a small (1kb-50mb) frame index file.
This also speeds up the whole process by reducing bottlenecks.
RIFE 4.0 - 6 MB 270 Frames Input - 1080p x2 - RIFE-NCNN:
1.35 GB Temp Folder, 01:05 minutes of total processing time
RIFE 4.0 - 6 MB 270 Frames Input - 1080p x2 - RIFE-NCNN-VS:
0.04 MB Temp Folder, 26 seconds of total processing time
This new implementation also supports the "usual" RIFE NCNN features, like fractional factors, allowing you to, for example, interpolate 24 to 60 without any downsampling etc.
I'm still working on fixing some bugs but expect a release very soon.