Make video smooth on your Mac — offline frame interpolation
Double or quadruple a video's frame rate for motion that glides instead of stutters — or switch modes and enlarge the clip 2× or 4× instead. Both run directly on your Mac: no upload, no render farm, no per‑minute charge, and nothing leaves the machine.
Two reasons people reach for this
Smooth motion. Footage shot at 24 or 30fps judders on pans and fast movement. Interpolating to 60 or 120fps smooths it out, which matters for screen recordings, gameplay capture, product videos and anything with a moving camera.
Slow motion you did not shoot for. Slowing 30fps footage down in an editor just repeats frames, and it looks it. Interpolate to 4× first and the slowed version has real in-between frames to play, so it stays fluid — which means you can rescue a shot you only captured once.
How it works
RIFE estimates the motion between each pair of frames and synthesises what belongs in the gap. It is not a blend or a blur — the generated frames are new images, which is why the result holds up when you slow it down and look closely.
Be realistic about time: every output frame has to be generated, so this is the slowest job in the suite and it scales with resolution and length. Each job reports its input and output frame rate and streams a real progress bar, so you know where it is rather than staring at a spinner.
It upscales too
Switch the mode from Smooth to Upscale and the same pipeline enlarges the clip instead of adding frames — 2× or 4× through Real‑ESRGAN, running on your Mac like everything else here. The frame rate is left alone; only the picture gets bigger.
Be realistic about the time. Every output frame is generated, so upscaling runs at roughly two seconds per 1080p frame on an M‑series Mac and climbs steeply with output size — a minute of footage is about an hour of rendering. Output is capped at 1080p on Lite and 4K on Pro, which is a deliberate guard against queueing a render that would take all day.
What it handles
- Input — MP4, MOV and M4V.
- Output — HEVC, at 2× or 4× the original frame rate, or 2× or 4× the original size.
- Resolution — up to 4K on Pro.
- Batches — queue several clips and Pro works through them in order.
Lite and Pro
Lite ships inside the free Rude Dog hub: 2× interpolation at up to 1080p, one clip at a time, with no watermark on the result. Enough to run your own footage through it and judge the output before paying anything.
Pro unlocks 4× interpolation, 4K input and batch queueing for £39 paid once. Renewing the update window later costs £19 and is optional — the version you bought keeps working either way.
Comparing the options
There are fewer frame-interpolation tools on macOS than on Windows, and you may already own one — free DaVinci Resolve includes optical-flow retiming. We wrote up the whole field, including why Flowframes is not an option on a Mac and when this one is not worth buying.
Coming from Topaz?
Topaz Video AI retired its perpetual licence in October 2025 and now sells subscriptions only. If that is what sent you here, the Interpolate vs Topaz Video AI comparison sets out honestly what this replaces — and what it does not, because Topaz still does restoration work that this does not.
Requirements
A Mac running macOS, and free disk space proportional to the clip you are processing. The engine ships inside the app, so there is nothing to download first and no connection required. Interpolate is signed and notarised by Apple, and installs through the free hub.
The other Rude Dog tools
- Transcribe — audio and video to text, offline
- Upscale — enlarge images up to 4× without losing detail
- Cutout — remove backgrounds, down to hair and fur
All four are covered by the Suite licence, and every one ships a free Lite tier inside the same hub download.
Questions
What does frame interpolation actually do?
It generates entirely new frames in between the ones you actually shot, so 30fps footage becomes 60 or 120fps. The result is either smoother motion at the original speed, or slow motion that stays fluid instead of stuttering — because there are real in-between frames to play rather than repeats.
Can I use it for slow motion?
Yes, and it is the most common reason to reach for it. Interpolate the clip to 4×, then slow the result down in your editor: it plays smoothly rather than juddering, without your having shot at a high frame rate. It can rescue a shot you only captured once.
Can it make a video bigger as well as smoother?
Yes. Switching to Upscale mode runs Real-ESRGAN over the clip instead of RIFE, enlarging it 2× or 4× without touching the frame rate. Output is capped at 1080p on Lite and 4K on Pro. It is slow — roughly two seconds per 1080p frame — because every output frame has to be generated.
Does it upload my video anywhere?
No. The RIFE engine is bundled inside the app and runs on your Mac. Video is decoded from disk, interpolated locally and encoded back to disk, with no upload, no render farm and no connection required. Nothing about your footage leaves the machine at any point in the process.
What files can it open?
MP4, MOV and M4V on the way in, which covers iPhone video, screen recordings and most editor exports. The result is encoded as HEVC. Anything unsupported is rejected up front with a message naming the three formats that work, rather than failing partway through a long job.
How high can the resolution go?
Pro handles input up to 4K. Lite caps the input at 1080p, which is full HD — enough to run your own footage through and judge the output before paying anything. The cap is checked before the job starts, so you are told immediately rather than after a long wait.
How long does it take?
Longer than the clip itself, and it scales with both resolution and length — every output frame has to be generated, which makes this the slowest job in the suite. Queue it and come back. Each job reports its input and output frame rate and streams a real progress bar.
Is it a subscription?
No. £39 once, and that version is yours permanently — it keeps working after the two-year update window closes. Renewing for £19 only re-opens access to newer builds; it is never required to keep using the version you already bought.