Auto Editor Effects

Documents

auto-editor-effects

Auto Editor Effects is an Agent Skill for documents published in the WyattBlue/auto-editor repository on GitHub: a SKILL.md instruction file an AI agent can load to do this task.

Apply actions and animations to sections of a video/audio with auto-editor — change speed, duck or fade volume, de-ess, zoom/Ken Burns, rotate/spin, draw boxes, overlay logos or picture-in-picture, and animate any of these with ramps and easing. Use when someone wants creative effects or per-section behavior rather than plain silence-cutting.

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How to use this skill

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Prompt to paste

Inspect the Agent Skill at https://github.com/WyattBlue/auto-editor/blob/HEAD/skills/auto-editor-effects/SKILL.md and all supporting files. Report provenance, permissions, scripts, dependencies, and security risks. Propose an exact installation into .agents/skills/auto-editor-effects, but wait for my approval before writing files or running scripts.

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Actions & animations

Instead of just cutting, give each section an action with --when-active (-w:1, loud) and --when-inactive (-w:0, silent). Defaults: -w:1 nil (keep), -w:0 cut. Chain actions with commas; they apply in order.

auto-editor video.mp4 -w:0 speed:8            # fast-forward through silence (pitch preserved)
auto-editor video.mp4 -w:0 speed:3,volume:0.5 # speed up AND halve volume of silent parts

-w:0/-w:1 are the silent (label 0) and active (label 1) classes. You can define more classes with --edit:N/-e:N and act on them with --when:N/-w:N (N = 2–255) — see the auto-editor skill's "Labels" section. Every action below works as the value of any -w:N.

Actions

Action	What it does	Form / range
`nil`	keep unchanged	—
`cut`	remove section	—
`speed`	time-stretch, pitch preserved	`speed:8`, `speed:0.5`
`varispeed`	speed via pitch shift (tape/vinyl)	`varispeed:2` (0.2–100)
`volume`	scale volume (1=normal, 0.5=−6dB)	`volume:0.2`
`deesser`	reduce sibilance	`deesser:intensity[:max[:freq]]` (each 0–1)
`invert`	invert pixels	—
`zoom`	zoom factor (1=none)	`zoom:2`, `zoom:0.5` (>0–100)
`rotate`	fixed clockwise rotation, expands so nothing clips	`rotate:90` (pair with `--resolution`)
`spin`	continuous spin `deg/rate` (deg per sec)	`spin:0/120`, `spin:90/-45`
`drawbox`	filled rectangle	`drawbox:x:y:w:h:color`
`pos`	place an overlay clip `x:y[:scale]`	mainly used inside `add` / v3
`add`	overlay an image/video layer	`add:path[:x:y:scale]`

auto-editor video.mp4 -w:1 deesser:0.8:0.7:0.4
auto-editor video.mp4 -w:1 rotate:90 --resolution 1080,1920   # landscape → portrait
auto-editor video.mp4 -w:1 drawbox:0:0:1920:200:#000000       # redact a strip

Overlays — `add`

add is virtual: it adds an overlay layer rather than a per-frame effect. Still images hold for the whole section; PNG alpha is preserved. Omit placement to scale-to-fit and center. Actions chained after an add apply to that new overlay, not the base.

auto-editor video.mp4 -w:1 add:./logo.png             # centered, fit to canvas
auto-editor video.mp4 -w:1 add:./pip.mp4:900:60:0.25  # quarter-size PiP in the corner
auto-editor video.mp4 -w:1 add:./logo.png,spin:0/-30  # the logo spins, not the base video
auto-editor song.mp3 -bg white -w:1 add:./cover.png   # audio + image → video

Overlays appear only where their section is kept, so for silent sections use -w:0 nil,add:... (keep + overlay). With --set-action the range is kept automatically.

Animations — ramps `from..to`

zoom, opacity, blur, brightness, volume, and each pos field accept a ramp. The value interpolates across the section, reaching to on its last frame. More than two points = keyframes, spread evenly.

auto-editor video.mp4 -w:1 zoom:1..1.5          # Ken Burns
auto-editor video.mp4 -w:1 opacity:0..1         # fade in
auto-editor video.mp4 -w:1 volume:0..1          # audio fade in
auto-editor video.mp4 -w:1 zoom:1..1.5..1       # zoom in then out (keyframes)
auto-editor video.mp4 -w:1 add:./logo.png,pos:0..1200:40:1..0.5  # slide + shrink overlay

Easing — :ease=curve[:duration], curve ∈ linear|in|out|inout. A standalone ease: token sets the curve for every animated action after it. rotate/spin are not affected by easing.

auto-editor video.mp4 -w:1 zoom:1..1.5:ease=inout
auto-editor video.mp4 -w:1 opacity:0..1:ease=in:2sec        # ease over 2s, then hold
auto-editor video.mp4 -w:1 ease:out,zoom:1..1.3,brightness:0..0.3

Target a time range — `--set-action`

--set-action ACTION,START,END overrides defaults for a range (range syntax; sec, start/end, negatives all work). The range is force-kept.

auto-editor video.mp4 --set-action nil,0,5sec
auto-editor video.mp4 --set-action speed:1.5,varispeed:1.5,30sec,end
auto-editor video.mp4 --set-action add:./logo.png:600:300:1.0,1sec,2sec

Recipes

auto-editor podcast.mp3 -w:0 cut -w:1 speed:1.15      # cut silence, tighten speech
auto-editor video.mp4 -w:0 volume:0.3                 # duck (not cut) the silence
auto-editor video.mp4 -w:1 varispeed:1.25             # nightcore (speed + pitch up)
auto-editor video.mp4 -w:0 speed:6,volume:0.4         # fast, quiet silent sections

Full reference: https://auto-editor.com/ref/actions.md. For plain cutting / pace / edit methods, see the auto-editor skill.