Video effects · Field Guide № 010
I built a video editor for 42 days. It had 109 releases and zero paying customers. Then I put it in the bin, because Claude can write the effects as code and a free engine renders them. This is the skill I use instead.
You need Claude Code, a Mac or Linux machine with Node 22 and ffmpeg, and a talking-head clip. Everything else is free and open source.
This reel, edited by the skill
What fires when
That is the reel this page came from. I filmed it on my phone and Claude edited it with the skill below. Captions run the whole way.
01
One paste in Terminal. It puts the skill where Claude Code looks for skills.
mkdir -p ~/.claude/skills && curl -fsSL https://danielwelsh.design/skills/reel-effects.tar.gz | tar -xz -C ~/.claude/skills
Then open Claude Code anywhere and paste this, with your own clip:
Use the reel-effects skill on ~/Movies/my-take.mov.
Prepare the first 20 seconds, read the transcript, and suggest 4 effects on the words that carry a number, a name or a turn.
Show me the snapshot sheet before you render.Read it before you run it: SKILL.md · the effect cards. Fonts default to Inter. Drop your own into the skill's fonts folder.
02
Almost every effect is a sandwich. Your cut-out sits between two layers of graphics, so things can go behind you and in front of you.
03
11 effects are built and checked on a real take. 14 more are written up as recipes, with the measurements, for Claude to build the first time you need one.
Ready
Recipes
02Couch wall
Your thumbnails tile the wall behind you.
03UI world
The wall becomes an app you are sitting inside.
04Frame break
The shot shrinks to a card and your head sticks out of it.
06Phone mockup
A phone swings in behind your shoulder and a button gets tapped.
07Checklist
Items type in as you say them and tick on the last word.
09Zoom-through cut
Fly into the frame and out of the next shot.
10Chart grow
A line chart draws itself behind your head.
11Pull-back reveal
The whole video shrinks into the app that made it.
12Green screen
The room is gone and you are in a studio.
13Paper cut
You become a sticker on a stop-motion collage.
15Vertigo
The room stretches while you stay the same size.
17Glass type
Clear acrylic letters on the wall behind you.
x2Freeze and label
The picture freezes and callouts point at you.
x3Before and after
A slider wipes from the raw clip to the edit.
04
Four steps. Paste each one into Claude Code and swap in your own paths.
The skill trims the clip, cuts you out of it, and gets word timings. The cut-out takes about 40 seconds of computer time per second of video, so start with 15 to 20 seconds.
Use reel-effects to prepare ~/Movies/my-take.mov from 0 to 18 seconds into ~/reels/take-01. Tell me where it found my head.One effect per beat, on a word you say. The visual starts about a quarter of a second before the word. That lead is what makes an edit feel tight.
Read take-01/transcript.json. Pick four words that carry a number, a name or a turn, and suggest one effect for each from the reel-effects index. Keep captions on the whole way.Claude assembles the page and takes snapshots at each effect. You look at one contact sheet instead of waiting for a render.
Write effects.json for those four, assemble it, lint it, and snapshot the middle of each effect. Fix anything covering my face before showing me.Eight seconds takes about two minutes on a laptop. The file comes out at 1080 by 1920 with your audio untouched.
Render take-01 to out.mp4, then make a frame sheet at 2 fps so I can check it.05
I measured his edited reels against mine. His cutting pace is ordinary. These are what actually differ.
Clip the mic to your chest
Never hold it at your chin. He does in zero of twelve reels.
Stay full frame
Put graphics over your chest, not in a split screen. He is full frame the whole time.
Say the keyword out loud
Then show it typed in a comment bar. His keyword reels get 20 comments per thousand plays. The rest get 1.
Title on frame zero
Three to eight words, over a sharp frame of your face. No blur intro.
Sit further back
Eyes at about a third of the way down. It leaves room beside your head for the effects.
Shoot two seconds of empty room
Before you sit down. Vertigo needs it, and it costs nothing.
06
The mistakes from building it, so they do not cost you anything.
Cards across the face
My first orbit sent the near cards straight through my face. Close takes need a taller ring, so the front pass lands under the chin.
White on white
White captions vanished when a white card passed behind them. A dark halo round the letters fixed it.
A word too wide
A seven-letter word at a fixed size ran off both edges. Fit it to the frame instead.
The fast cut-out setting
The GPU option is known to damage faces. Run the cut-out on the CPU and wait.
Splitting the cut-out
I ran it in three parallel pieces to go faster. Each piece ran three times slower. Start it and go make a coffee.
Effects as the fix
Polish does not predict plays. His biggest reels are selfies. Fix the mic, the hook and the keyword first.
The effects come from taking @tenfoldmarc's "17 video effects claude can create" apart frame by frame, then rebuilding each one from scratch on HyperFrames, HeyGen's open-source renderer. Go and follow him.
The editor took me 42 days. The skill took an afternoon. Claude writes the effects, a free engine renders them, and your taste is the only part that cannot be downloaded.