SKILL.md
FFmpeg Video Filters Skill
Apply video filters for scaling, cropping, watermarks, speed changes, and visual effects.
When to Use
- Resize videos
- Crop video frames
- Add watermarks or overlays
- Change playback speed
- Apply blur or other effects
- Adjust brightness/contrast
Scaling
# Scale to 720p (maintain aspect ratio)
ffmpeg -i input.mp4 -vf scale=-2:720 output.mp4
# Scale to specific width (maintain aspect ratio)
ffmpeg -i input.mp4 -vf scale=1280:-2 output.mp4
# Scale to exact dimensions (may distort)
ffmpeg -i input.mp4 -vf scale=1920:1080 output.mp4
# Scale with algorithm
ffmpeg -i input.mp4 -vf scale=1280:720:flags=lanczos output.mp4
Cropping
# Crop to 16:9 from center
ffmpeg -i input.mp4 -vf "crop=1920:1080" output.mp4
# Crop with offset (x:y:width:height)
ffmpeg -i input.mp4 -vf "crop=1920:1080:0:0" output.mp4
# Crop from specific position
ffmpeg -i input.mp4 -vf "crop=800:600:100:50" output.mp4
Watermarks and Overlays
# Add image watermark (top-left)
ffmpeg -i input.mp4 -i logo.png \
-filter_complex "overlay=10:10" output.mp4
# Bottom-right watermark
ffmpeg -i input.mp4 -i logo.png \
-filter_complex "overlay=W-w-10:H-h-10" output.mp4
# Center watermark
ffmpeg -i input.mp4 -i logo.png \
-filter_complex "overlay=(W-w)/2:(H-h)/2" output.mp4
Speed Changes
# Speed up 2x
ffmpeg -i input.mp4 -vf "setpts=0.5*PTS" -af "atempo=2.0" output.mp4
# Slow down 0.5x
ffmpeg -i input.mp4 -vf "setpts=2.0*PTS" -af "atempo=0.5" output.mp4
# Speed up video only (no audio)
ffmpeg -i input.mp4 -vf "setpts=0.5*PTS" -an output.mp4
Blur Effects
# Blur entire video
ffmpeg -i input.mp4 -vf "boxblur=10:5" output.mp4
# Blur specific region (coordinates x:y:w:h)
ffmpeg -i input.mp4 -vf "boxblur=10:5:x=100:y=100:w=200:h=200" output.mp4
# Gaussian blur
ffmpeg -i input.mp4 -vf "gblur=sigma=5" output.mp4
