FFmpeg xfade Transition Reference — effect skill for transitions
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All 58 built-in xfade transitions plus custom expressions, grouped by look, with the options that matter.
- Type: Effect · Transitions
- Slug:
ffmpeg-xfade-reference - Status: live
- Publisher: varg (varg, verified)
- License: MIT
- Source: https://github.com/vargHQ/skills/blob/main/varg-video-edit-library/references/transitions.md#ffmpeg-xfade-reference
- Works in: Claude Code, Claude.ai, Codex, Cursor, OpenClaw, Gemini CLI, Any MCP client, varg Studio
- Requires: ffmpeg
- Cost: Free — the take renders locally; generated footage, if any, bills by the model
What it does
Fades, wipes, slides, covers/reveals, shape opens, slices, wind, squeeze, zoom, pixelize, blur.
When: Pick a transition name for any ffmpeg join; check here before writing a custom expression.
Watch out: Expecting camera-style effects (whip, spin, shake, glitch, light leak, 3D) from xfade; those need filter chains or GL/HTML engines.
Timing: duration 0–60 s (default 1); offset in seconds from the first input's start (default 0)
Also called: xfade list, xfade transitions, xfade names, xfade custom expr
In FFmpeg
Options: transition, duration, offset, expr. Both inputs must be constant frame rate with the same resolution, pixel format, frame rate and timebase.
Fades: fade, fadefast, fadeslow, fadeblack, fadewhite, fadegrays, dissolve (dithered), distance. Wipes: wipeleft/right/up/down, wipetl/tr/bl/br, diagtl/tr/bl/br, smoothleft/right/up/down (soft edge). Moves: slideleft/right/up/down (push), coverleft/right/up/down (B over A), revealleft/right/up/down (A off B). Shapes: circleopen, circleclose, circlecrop, rectcrop, vertopen, vertclose, horzopen, horzclose, radial (clock). Slices and wind: hlslice, hrslice, vuslice, vdslice, hlwind, hrwind, vuwind, vdwind. Other: squeezeh, squeezev, zoomin, pixelize, hblur, custom.
Custom: variables X, Y, W, H, P, PLANE, A, B and a0..a3(x,y), b0..b3(x,y). P runs from 1 at the start of the transition to 0 at the end (verified), so if(gt(X/W,P),B,A) reveals B from the right:
ffmpeg -i a.mp4 -i b.mp4 -filter_complex \
"[0:v]fps=30,settb=AVTB,format=yuv420p[a];[1:v]fps=30,settb=AVTB,format=yuv420p[b];\
[a][b]xfade=transition=custom:duration=0.6:offset=4.4:expr='if(gt(mod(Y*10/H,1),P),B,A)'[v]" -map "[v]" blinds.mp4
GPU variants exist (xfade_opencl, xfade_vulkan) with a smaller set.
Where this comes from
Use when
- Pick a transition name for any ffmpeg join; check here before writing a custom expression.
Not for
- Expecting camera-style effects (whip, spin, shake, glitch, light leak, 3D) from xfade; those need filter chains or GL/HTML engines.
Install
- Claude Code:
claude plugin marketplace add vargHQ/skills && claude plugin install varg@varg - Codex:
npx skills add vargHQ/skills --skill varg-video-edit-library -a codex -y - Cursor:
npx skills add vargHQ/skills --skill varg-video-edit-library -a cursor -y
Example output
https://s3.varg.ai/how-to/previews/4040c86aea42/take-ffmpeg-xfade-reference.mp4 — circleclose between two shots, with the timeline strip of the edit. Footage: Cosmos Laundromat (2015), (CC) Blender Foundation | gooseberry.blender.org, CC BY 4.0; Big Buck Bunny (2008), (c) copyright 2008, Blender Foundation | www.bigbuckbunny.org, CC BY 3.0. (credit: Rendered by varg · Cosmos Laundromat (2015) + Big Buck Bunny (2008))
More transitions skills
- editly: Declarative JSON5 video editing CLI/API: clips, titles, transitions, audio mixing, rendered with ffmpeg.
- Mix (Cross Dissolve): The two shots blend through each other. The quietest transition: "time passes" or "this continues".
- Dip to Black: A fades to black, then B fades up. Marks the end of a section or a bigger jump in time.
- White Flash: The frame blows out to white for a moment and opens on the next shot. Energy, memory or a camera snap.
- Pull In (Zoom In): The camera rushes into shot A and lands, still moving forward, in shot B. The signature short-form transition.
- Pull Out (Zoom Out): The camera jerks backwards out of shot A and keeps pulling back as shot B settles in.