Basic Usage

Getting Media Info

ffprobe

Inspect any media file without modifying it:

# Quick info
ffprobe video.mp4

# Detailed stream info
ffprobe -v error -show_streams -show_format video.mp4

# JSON format (for scripting)
ffprobe -v error -show_streams -show_format -of json video.mp4

# Specific stream info
ffprobe -v error -select_streams v:0 -show_entries stream=codec_name,width,height -of csv=p=0 video.mp4

Converting Between Formats

Lossless Remux

No re-encoding — just change the container:

# MKV to MP4 (lossless)
ffmpeg -i input.mkv -c copy output.mp4

Re-encode for Compatibility

# AVI to MP4 with H.264
ffmpeg -i input.avi -c:v libx264 -preset fast -crf 23 \
  -c:a aac -b:a 128k output.mp4

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

# MOV with ProRes for editing
ffmpeg -i input.mov -c:v prores_ks -profile:v 3 \
  -c:a pcm_s16le output.mov

Working with Video

Extract Frames

# Extract single frame at timestamp
ffmpeg -ss 00:01:23 -i input.mp4 -frames:v 1 screenshot.jpg

# Extract every nth frame
ffmpeg -i input.mp4 -vf "select=not(mod(n\,100))" -vsync vfr frame_%04d.png

Concatenate Videos

Method 1: concat demuxer (reliable)

# Create a file list
echo "file 'part1.mp4'" > files.txt
echo "file 'part2.mp4'" >> files.txt
echo "file 'part3.mp4'" >> files.txt

# Concatenate
ffmpeg -f concat -safe 0 -i files.txt -c copy merged.mp4

Method 2: concat protocol (for streams of same codec)

ffmpeg -i "concat:part1.mp4|part2.mp4|part3.mp4" -c copy merged.mp4

Working with Audio

Extract Audio

# Extract audio track (copy)
ffmpeg -i input.mp4 -vn -c:a copy audio.m4a

# Extract and re-encode
ffmpeg -i input.mp4 -vn -c:a libmp3lame -b:a 192k audio.mp3

Add Audio to Video

ffmpeg -i video.mp4 -i audio.mp3 -c:v copy \
  -c:a aac -b:a 192k -shortest output.mp4

Replace Audio Track

ffmpeg -i video_with_audio.mp4 -i new_audio.aac \
  -c:v copy -c:a aac -map 0:v:0 -map 1:a:0 output.mp4

Useful Global Flags

Flag	Description
-y	Overwrite output without asking
-n	Never overwrite (exit if exists)
-hide_banner	Suppress version/copyright info
-loglevel level	Control verbosity (quiet, fatal, error, warning, info, verbose, debug)
-threads n	Limit CPU threads used
-progress url	Write progress to file or URL