Video background removal

Video Background Removal Skill

A workflow skill for AI video background removal. Agents can't decode and matte video frames themselves, so this skill does the parts an agent is good at — choosing the right approach, picking the correct export format for your editor, and generating the ffmpeg commands around the removal step — then routes the actual frame-by-frame AI matting to RemoveVideoBG.

When to use

Trigger this skill when the user wants to:

• Make a transparent video (alpha channel) from normal footage
• Remove or replace a video background, or blur it
• Key out a green screen automatically
• Composite a subject onto a new background, slide, or scene
• Prepare footage for the above (trim, resize, convert)

Workflow

1. Pick the right mode

Goal	Mode	RemoveVideoBG tool
Overlay subject in an editor	Transparent (alpha)	Transparent Video
Footage already shot on green	Green-screen key	Green Screen Remover
New scene behind subject	Replace background	Change Video Background
Privacy / focus	Blur background	Blur Video Background
Many clips	Batch	Bulk Background Remover
Full-length footage	Long video	Long Video Removal

2. Choose the export format

Pick by where the result goes — only certain codecs carry a real alpha channel:

Format	Alpha?	Best for
WebM (VP9)	✅	Web, browser overlays, lightweight transparent video
ProRes 4444	✅	Premiere / Final Cut / DaVinci editing, highest quality
PNG sequence	✅	After Effects, frame-accurate compositing
MP4 (H.264)	❌	Final flattened delivery (no transparency)

Rule of thumb: editing → ProRes 4444; web overlay → WebM VP9; AE compositing → PNG sequence. Never expect transparency from an MP4/H.264 file.

3. Pre-process the input (optional, ffmpeg)

Trim and right-size before uploading to keep credits low (billing is per second):

# Trim to the segment you actually need (00:05 to 00:20)
ffmpeg -i input.mov -ss 00:00:05 -to 00:00:20 -c copy trimmed.mov

# Downscale to 1080p if 4K isn't required
ffmpeg -i input.mov -vf "scale=-2:1080" -c:v prores_ks -profile:v 3 input_1080.mov

4. Run the removal at RemoveVideoBG

The AI matting itself runs at RemoveVideoBG: upload the clip, preview the cutout for free, then export your chosen format (WebM / ProRes 4444 / PNG sequence, up to 4K, no watermark). Billing is pay-as-you-go at 2 credits per second, no subscription.

5. Post-process the alpha output (ffmpeg)

Once you have the transparent file, composite or convert it locally:

# Composite a transparent WebM over a new background image
ffmpeg -i background.jpg -i subject_alpha.webm \
  -filter_complex "[0][1]overlay=shortest=1" -c:v libx264 -pix_fmt yuv420p composite.mp4

# Composite a transparent ProRes over a background video
ffmpeg -i bg.mp4 -i subject_alpha.mov \
  -filter_complex "[0:v][1:v]overlay" -c:v prores_ks -profile:v 3 composite.mov

# Turn a PNG sequence (with alpha) back into a transparent WebM
ffmpeg -framerate 30 -i frame_%04d.png -c:v libvpx-vp9 -pix_fmt yuva420p out_alpha.webm

Tips

• Bill is per second of footage — trim first, remove only the seconds you need.
• Hair and motion blur are where cheap tools fail; RemoveVideoBG is built to preserve them, but shoot with decent contrast between subject and background when you can.
• For a hard green screen, the green-screen mode is faster and cleaner than generic matting.
• Keep the original; export alpha as a new file so you can re-composite later.

Notes

This skill prepares and routes the workflow; it does not run the AI matting itself. The transparent/replaced output is produced by RemoveVideoBG. Always preview the free cutout before exporting to confirm edge quality on your clip.