Framerate Converter

Part of the Trope Tools suite — by TropeMedia.

Two simple ComfyUI nodes for working with video files:

• Convert Framerate — change a video's frame rate (24 → 25, 30 → 25, anything to anything).
• Remux Container — change a video's container (.mov ↔ .mp4 ↔ .mkv) without re-encoding, so no quality loss.

Both nodes use ComfyUI's standard VIDEO type, so you can chain them together or wire them into the built-in Load Video / Save Video nodes.

What they do

Convert Framerate

Converts videos between any common framerates — 24, 25, 30, 60 fps and anything in between. Useful for:

• Film → PAL (24 → 25 fps)
• NTSC film → PAL (23.976 → 25 fps)
• PAL → film (25 → 24 fps)
• NTSC → PAL (30 / 29.97 → 25 fps)
• Slowing 60 fps footage to 30 fps
• Anything else FFmpeg can do

Audio stays in sync. Quality stays high. You don't need to know any FFmpeg.

Remux Container

Swaps the container format around the same video and audio streams — no re-encoding, no quality loss, runs in seconds even on long files. Useful for:

• Putting an .mp4 inside a .mov so it imports cleanly into Final Cut / Resolve
• Moving footage out of .mkv for editors that don't read it
• Standardising deliverables to a single container

Install (the easy way)

Option 1 — ComfyUI Manager (recommended)

1. Open ComfyUI Manager.
2. Search for Trope Tools — Framerate Converter.
3. Click Install.
4. Restart ComfyUI.

Option 2 — Manual

1. Find your ComfyUI custom_nodes/ folder.
2. Drop this folder inside it.
3. Restart ComfyUI.

One thing you need separately: FFmpeg

This node uses FFmpeg under the hood — it's a free tool you install once and forget about.

| Your computer | What to type / do | |---|---| | Mac | Open Terminal, paste brew install ffmpeg, hit enter. (Don't have Homebrew? Get it at brew.sh.) | | Windows | Download the build from gyan.dev/ffmpeg/builds, unzip it, and add the bin/ folder to your PATH. (Step-by-step guide.) | | Linux | sudo apt install ffmpeg (or your distro's equivalent). |

If FFmpeg isn't installed, the ComfyUI console shows a clear warning when it starts up — so you'll know.

No pip install needed. This pack uses only Python's standard library.

How to use it

The simplest possible workflow:

[Load Video]  →  [Convert Framerate]  →  [Save Video]

1. Right-click the canvas → Add Node → Trope Tools → Framerate Converter → Convert Framerate.
2. Connect a Load Video node (any source) into the input slot.
3. Set target_fps (default is 25.0 — change it to whatever you need).
4. Connect output to a Save Video node.
5. Hit Queue Prompt.

That's it. The converted video saves to ~/comfyui/output/.

You can also skip Save Video — Convert Framerate already drops a converted file into ~/comfyui/input/ named <original>_<targetfps>fps.mp4.

Chaining the two nodes together

Because both nodes use the VIDEO type, you can wire them directly:

[Load Video]  →  [Convert Framerate]  →  [Remux Container]

This lets you change the framerate and the container in a single pass — for example, "take this 24 fps .mp4 and give me a 25 fps .mov."

Don't pipe Remux Container into Save Video. The built-in Save Video node ignores the input's container and re-saves as .mp4, which would undo the remux. Remux Container writes its output straight to ~/comfyui/output/ itself — set filename_prefix on the node to control the name.

The settings (only if you want to tweak)

The defaults work for most jobs. If you want to fine-tune:

method — how the conversion is done

| Method | What it does | When to use it | |---|---|---| | speed_change (default) | Adjusts playback speed slightly, keeps every frame | Small fps changes like 24 ↔ 25 — gives the cleanest result | | frame_drop | Drops or duplicates frames | Big jumps like 60 → 30 fps | | frame_blend | Blends adjacent frames together | Smoother than frame_drop, slight ghosting | | minterpolate | AI-style motion interpolation | Highest quality up-conversion, but slow |

audio_mode — how the audio is handled (only matters with speed_change)

| Mode | What happens | |---|---| | allow_shift (default) | Audio plays at the new speed; pitch shifts a tiny bit (~0.7 semitones for 24→25). Most people can't hear it. | | preserve_pitch | Audio is re-pitched so it sounds the same as the original. | | copy | Original audio is kept untouched (will go out of sync — only useful for tests). | | no_audio | Strips audio entirely. |

crf — quality dial

Number from 0 (huge file, perfect quality) to 51 (tiny file, awful quality). Default is 18, which looks essentially identical to source. Lower = better.

Mac users — about Full Disk Access

The ComfyUI desktop app on Mac is sandboxed. By default it can only read/write inside ~/comfyui/. If you want to convert a video sitting somewhere else on your computer:

System Settings → Privacy & Security → Full Disk Access → + → add ComfyUI.app → restart it.

If you're happy dragging files into the Load Video node (the normal way), you don't need to do this at all.

Help, something's wrong

"ffmpeg not found" warning when ComfyUI starts You haven't installed FFmpeg yet — see the install section above.

"No such file or directory" The video file path probably has weird characters in it, or it's outside ComfyUI's sandbox. Use the upload widget on Load Video instead of typing a path.

Audio is out of sync after conversion Try setting audio_mode to preserve_pitch. If it's still off, your source video might have a variable framerate (some phone recordings do this) — you'd need to convert it to a constant framerate first.

Output looks lower-quality than the source Lower the crf number. 14 is near-source quality, 0 is fully lossless (much bigger files).

More than two nodes?

This pack is built around two simple nodes — Convert Framerate and Remux Container — which is what 99% of people need. Underneath, there are 12 smaller building-block nodes (Probe Video, Calc Conversion, Run FFmpeg, Verify FPS, etc.) you can use to build custom workflows if you want fine-grained control. They're tucked away under the Trope Tools / Framerate Converter / Inspect, Configure, Process, Verify menus. Most users will never need them.

Credits

• Built around FFmpeg — the open-source video toolkit.
• Published by TropeMedia.

License

MIT — see LICENSE.