Video Edit

Edit videos locally by running ffmpeg/ffprobe directly. No wrapper scripts needed.

Prerequisites

Install ffmpeg (includes ffprobe):

macOS

brew install ffmpeg

Ubuntu/Debian

sudo apt update && sudo apt install -y ffmpeg

Verify

ffmpeg -version && ffprobe -version

Quick Reference

Get video info

ffprobe -v quiet -print_format json -show_format -show_streams video.mp4

Trim

ffmpeg -y -ss 00:00:30 -to 00:01:45 -i video.mp4 -c copy trimmed.mp4

Concatenate clips

1. Create a file list

printf "file '%s'\n" clip1.mp4 clip2.mp4 clip3.mp4 > list.txt

2. Concat with stream copy

ffmpeg -y -f concat -safe 0 -i list.txt -c copy joined.mp4

Resize for platform

ffmpeg -y -i video.mp4
-vf "scale=1080:1920:force_original_aspect_ratio=decrease,pad=1080:1920:(ow-iw)/2:(oh-ih)/2:black"
-c:a copy tiktok.mp4

Change speed

2x faster

ffmpeg -y -i video.mp4 -filter:v "setpts=0.5*PTS" -filter:a "atempo=2.0" fast.mp4

0.5x (slow motion)

ffmpeg -y -i video.mp4 -filter:v "setpts=2.0*PTS" -filter:a "atempo=0.5" slow.mp4

Extract audio

ffmpeg -y -i video.mp4 -vn -acodec libmp3lame audio.mp3

Replace audio

ffmpeg -y -i video.mp4 -i audio.mp3 -c:v copy -map 0:v:0 -map 1:a:0 -shortest output.mp4

Compress

ffmpeg -y -i video.mp4 -crf 23 -preset medium -c:a copy compressed.mp4

Convert format

ffmpeg -y -i video.mov output.mp4

Add image overlay

Logo in top-right corner

ffmpeg -y -i video.mp4 -i logo.png
-filter_complex "overlay=W-w-10:10" -c:a copy watermarked.mp4

Platform Presets

Platform Resolution Scale + pad filter

TikTok 1080 x 1920 scale=1080:1920:force_original_aspect_ratio=decrease,pad=1080:1920:(ow-iw)/2:(oh-ih)/2:black

YouTube 1920 x 1080 scale=1920:1080:force_original_aspect_ratio=decrease,pad=1920:1080:(ow-iw)/2:(oh-ih)/2:black

Instagram 1080 x 1350 scale=1080:1350:force_original_aspect_ratio=decrease,pad=1080:1350:(ow-iw)/2:(oh-ih)/2:black

Square 1080 x 1080 scale=1080:1080:force_original_aspect_ratio=decrease,pad=1080:1080:(ow-iw)/2:(oh-ih)/2:black

Twitter/X 1920 x 1080 scale=1920:1080:force_original_aspect_ratio=decrease,pad=1920:1080:(ow-iw)/2:(oh-ih)/2:black

Use the filter with: ffmpeg -y -i input.mp4 -vf "<filter>" -c:a copy output.mp4

Tips

• Always use -y to overwrite output without prompting.

• Use -c copy when you only need to cut/join (no re-encoding, very fast).

• Lower CRF = better quality, larger file. Range 18-28 is typical; 23 is the default.

• For detailed recipes and flag explanations, see references/operations.md .