ffmpeg-toolkit

name	ffmpeg-toolkit
description	Video and audio processing with FFmpeg. Covers transcoding, resizing, trimming, speed adjustment, compression, audio extraction, concatenation, cropping, thumbnails, and probing. References available for codec/filter lookup, audio processing, streaming formats, Remotion integration, and platform export.

FFmpeg Toolkit

Transcode

# Convert to MP4 (H.264 + AAC)
ffmpeg -i input.mov -c:v libx264 -preset medium -crf 23 \
       -c:a aac -b:a 128k output.mp4

# Convert to WebM (VP9 + Opus)
ffmpeg -i input.mp4 -c:v libvpx-vp9 -crf 30 -b:v 0 \
       -c:a libopus -b:a 128k output.webm

Resize

# Specific dimensions
ffmpeg -i input.mp4 -vf "scale=1920:1080" output.mp4

# Aspect-ratio preserve with padding (letterbox/pillarbox)
ffmpeg -i input.mp4 -vf "scale=1920:1080:force_original_aspect_ratio=decrease,pad=1920:1080:(ow-iw)/2:(oh-ih)/2" output.mp4

# Crop to fill (no black bars)
ffmpeg -i input.mp4 -vf "scale=1920:1080:force_original_aspect_ratio=increase,crop=1920:1080" output.mp4

# Scale to width, auto height
ffmpeg -i input.mp4 -vf "scale=1280:-2" output.mp4

# Scale to percentage (50%)
ffmpeg -i input.mp4 -vf "scale=iw/2:ih/2" output.mp4

Trim and Cut

# Cut from timestamp + duration (re-encode recommended for accuracy)
ffmpeg -i input.mp4 -ss 00:00:30 -t 00:00:15 -c:v libx264 -c:a aac output.mp4

# Cut from start to end timestamp
ffmpeg -i input.mp4 -ss 00:00:30 -to 00:00:45 -c:v libx264 -c:a aac output.mp4


ffmpeg -i input.mp4 -ss 00:00:30 -t 00:00:15 -c copy output.mp4


ffmpeg -ss 00:10:00 -i large_video.mp4 -t 00:05:00 -c copy clip.mp4