🔥VideoTransition

VideoTransition stitches two clips together with an actual transition effect - fade, wipe, slide, circle, pixelize, and a couple dozen more - instead of just hard-cutting from one to the other. If you're assembling a short film out of AI-generated shots, this is the polish step that makes it feel like something edited rather than something queued. It's a direct wrapper around FFmpeg's xfade filter, which is exactly why the transition list behaves a little oddly (more on that below).

How it works

Both videos are normalized first - scaled to the reference video's dimensions (letterboxed with black bars if the aspect ratios differ), forced to its fps, and converted to yuv420p - then run through xfade at the offset you choose. When both inputs have audio it goes the extra mile: it crossfades the two soundtracks with acrossfade instead of just chopping them. That's genuinely nicer than most DIY ffmpeg one-liners.

The inputs that matter

• video1_path / video2_path - video1 plays first, then the transition into video2.
• reference_video - video1 or video2; this decides the output resolution and frame rate. Both clips get resized to it.
• transition - the effect. Here's the weird part: the dropdown is populated at runtime by actually running ffmpeg -h filter=xfade on your machine, so the list you see is whatever your FFmpeg build supports. If an effect you were promised is missing, that's your FFmpeg version, not the node.
• transition_duration - how long the crossfade lasts, min 0.1 s, hard cap 3 s.
• offset - the point (in seconds) in video1 where the transition starts. The node enforces that offset must be less than video1's duration minus the transition duration, and will error out with a math-y message if you violate it.

Outputs

Just one: video_complete_path, the timestamped path of the finished render.

Install

Pack-wide story, one more time: FFmpeg on PATH is the real requirement, the Python dependency is a rounding error. Manager search "ComfyUI-FFmpeg", or:

cd ComfyUI/custom_nodes
git clone https://github.com/MoonHugo/ComfyUI-FFmpeg
cd ComfyUI-FFmpeg
pip install -r requirements.txt

Restart and you're in.

Gotchas

• The output file auto-names with a timestamp - every render is a new file, which is either nice (no accidental overwrites) or annoying (disk clutter) depending on how many takes you're doing.
• If the transition dropdown comes up empty, your FFmpeg build either lacks the xfade filter or isn't on PATH - check ffmpeg -h filter=xfade in a terminal yourself. If that command errors, fix FFmpeg before touching this node.
• This is a full re-encode (both streams go through the filter graph), so it's slow-ish for long clips. A 10-second pair of shots is fine; a 20-minute pairing will feel like it's hanging. It's not - ffmpeg is just working.