FFMPEG Quick Hacks
::: by V. Subhash :::
An FFmpeg tutorial, hack collection and quick-reference

Table of Contents
What you can expect from ‘FFMPEG Quick Hacks’ Videos for code examples in the book All-in-one video demo How to fade in fade out audio and video How to generate noise in audio and video How to bleep part of a video How to add audio waveforms to video How to reverse audio and video MP3-to-MP4 or audio-to-video conversion using audio power spectrum filter How to add echo to a video Blurring a portion of a video Write text on video Render transparent GIF on video with infinite looping Replace green-screen background on another video Fade into another video using a transition effect Slow down a video Subtitle a video Acknowledgements & Thanks About FFMPEG

Table of Contents

What you can expect from ‘FFMPEG Quick Hacks’
Videos for code examples in the book
Acknowledgements & Thanks
About FFMPEG

FFMPEG Quick Hacks can help you quickly learn to use the free command-line video-editing utility FFmpeg - cut, copy, record, edit, tag, convert, rotate, flip, resize, crop, combine, compose, blur, sharpen, smoothen, side-by-side split, PIP inset, fade in/out... Also learn to use subtitles, audio/image files and metadata with video.

The book is a novel attempt to bring this great software program to the masses. It uses powerful learning cues to make concepts clear and interesting to the reader. It is neatly designed and richly illustrated better than any other traditionally published book. Check the ebook or the excerpts PDF document (scroll down) to see what I mean.

This book was created entirely using Free and Open-Source Software (FOSS). And, by that, I do not just mean 'not exported from Microsoft word'. I have written, illustrated, formatted and designed the book using a variety of freedom-oriented software.

This book is being replaced with a better one and has become temporarily unavailable.

Notes

Videos: 'FFMPEG Quick Hacks' book playlist
Intro article: Cool FFmpeg Tips and Tricks (from 2016)
Follow-up article: Open Source For You magazine September 2020 edition.
Sample PDF: This sample is a low-resolution watermarked PDF but it is fully functional.
Download
ffmpeg-quick-hacks-book-sample.pdf
26 pages, full-color, includes TOC, 2 MB

What you can expect from FFMPEG Quick Hacks

A simple introduction to FFmpeg and related multimedia concepts - containers, streams, channels, maps, metadata...
Learn to convert from one format to another - video-to-video, video-to-audio, video-to image, image-to-video, audio-to-video...
Get ready to edit video - cut videos with and without re-encoding, append (concatenate) videos, resize videos, change contrast...
Go bonkers with filters - rotate, flip, crop, side-by-side split, PIP inset, remove logo, blur, smoothen/sharpen, draw box, draw text, speed up, slow down, fade in/out...
Go all in with audio - convert, change volume, mix channels, detect silence, display waveforms...
Get subversive with subtitles - place them anywhere on the screen, use custom fonts and colors, specify languages, burn them into the video...
Get mental with metadata - add MP3 tags including album art, set global and stream-specific metadata, remove metadata...
Learn several useful tips that makes tough tasks easy

Overall, the book can be used as an FFmpeg tutorial, a hack collection and a desk-side reference.

About FFmpeg

You can read the article 'Cool FFmpeg Tips and Tricks' that I wrote for Open Source For You magazine some years ago for an easy introduction to FFmpeg. You can then buy my book for more.

Subscribe to my newsletter

The details are mentioned in my author newsletter blogpost. Full/sample PDF ebooks of several books are listed in it. You do not have to subscribe to download them. However, if you do subscribe, you get a FREE 200-puzzle combined ebook version of my World of Word Ladders books.

Videos for the code examples in the book

The following videos are available in this online video playlist.

All-in-one video demo at the end of the book

This video uses several FFmpeg techniques described in the book.

How to fade in fade out audio and video

# Create the fade-in-fade-out video
ffmpeg -y \
  -i Do-Aliens-Exist-We-Asked-a-NASA-Scientist.mp4 \
  -i irs-tax-advice-for-alien-mates.mp4 \
  -filter_complex \
  "[0:v:0]trim=start=0:end=6, setpts=PTS-STARTPTS[v1];
  [1:v:0]trim=start=3:end=9, setpts=PTS-STARTPTS[v2];
  [0:v:0]trim=start=6:end=9, setpts=PTS-STARTPTS[v3];
  [1:v:0]trim=start=0:end=3, setpts=PTS-STARTPTS[v4];
  [v3]fade=t=out:d=3:alpha=1, setpts=PTS-STARTPTS[nasafade];
  [v4]fade=t=in:d=3:alpha=1, setpts=PTS-STARTPTS[irsfade];
  [nasafade][irsfade]overlay, setpts=PTS-STARTPTS[fading];
  [v1][fading][v2]concat=n=3:v=1:a=0[v]" \
  -map '[v]' \
  aliens-r-us.m4v

# Create the fade-in-fade-out audio
ffmpeg -y \
  -i Do-Aliens-Exist-We-Asked-a-NASA-Scientist.mp4 \
  -i irs-tax-advice-for-alien-mates.mp4 \
  -filter_complex \
  "[0:a:0]atrim=start=0:end=6, asetpts=N/SAMPLE_RATE/TB[a1];
  [1:a:0]atrim=start=3:end=9, asetpts=N/SAMPLE_RATE/TB[a2];
  [0:a:0]atrim=start=6:end=9, asetpts=N/SAMPLE_RATE/TB[a3];
  [1:a:0]atrim=start=0:end=3, asetpts=N/SAMPLE_RATE/TB[a4];
  [a3]afade=t=out:d=3, asetpts=N/SAMPLE_RATE/TB[nasafade];
  [a4]afade=t=in:d=3, asetpts=N/SAMPLE_RATE/TB[irsfade];
  [nasafade][irsfade]amix[afading];
  [a1][afading][a2]concat=n=3:v=0:a=1[a]" \
  -map '[a]' \
  aliens-r-us.m4a

# Mixes the fade-in-fade-out video and audio
ffmpeg -i aliens-r-us.m4v -i aliens-r-us.m4a aliens-r-us.mp4

The video for this example will be available soon.

How to convert a video into a GIF?
This is my software implementation of Chandler Bing's Run, Yasmine! Run! problem.
```
ffmpeg -y -i baywatch.m4v \
  -filter_complex
  "fps=7,scale=w=320:h=-1:flags=lanczos,split[v1][v2];
  [v1]palettegen=stats_mode=diff[p];
  [v2][p]paletteuse=dither=bayer:bayer_scale=4" \
run-yasmine-run-4.gif
```
This gives you good frame quality and file size, but the motion is not smooth.

If you change the filter to paletteuse=dither=bayer:bayer_scale=0, you get smoother motion but bigger file size and a dotted texture.

How to generate noise in audio and video

ffmpeg -y -i barbara.mp4 \
  -filter_complex \
     "[0:v:0]noise=alls=100:allf=a+t:enable='between(t,6,12)'[v]; 
      [0:a:0]atrim=start=0:end=6, asetpts=N/SAMPLE_RATE/TB[fa]; 
      anoisesrc=color=brown:d=6[ma]; 
      [0:a:0]atrim=start=12:end=20, asetpts=N/SAMPLE_RATE/TB[la];
      [fa][ma][la]concat=n=3:v=0:a=1[a]" \
  -map "[v]" -map "[a]" \
  -t 0:0:20 \
  barb-intermission.mp4

How to bleep part of a video

ffmpeg -y -i barbara.mp4 \
  -filter_complex \
    "[0:a:0]atrim=start=0:end=5, asetpts=N/SAMPLE_RATE/TB[a1];
     sine=frequency=1000:duration=2[a2]; 
     [0:a:0]atrim=start=7:end=10, asetpts=N/SAMPLE_RATE/TB[a3];
     [a1][a2][a3]concat=n=3:v=0:a=1[a]" \
  -map 0:v:0 -map '[a]' \
  -t 0:0:10 \
  barb-bleep.mp4; totem barb-bleep.mp

How to add audio waveforms to video

ffmpeg -i ace-ventura-reversed.mp4 \
  -filter_complex \
    "[0:a:0]showfreqs=s=200x100:mode=bar[chartf];
     [0:a:0]showvolume=w=200:h=40[chartv];
     [0:a:0]showwaves=s=200x40[chartw];
     [0:v:0][chartw]overlay=x=20:y=60[v1];
     [v1][chartv]overlay=x=20:y=120[v2];
     [v2][chartf]overlay=x=20:y=200[v]" \
  -map '[v]' -map 0:a:0 \
  ace-charts.mp4

How to reverse audio and video

ffmpeg -y -i ace-ventura-reverse.mp4 \
  -filter_complex \
     "[0:v:0]reverse[v]; [0:a:0]areverse[a]" \
  -map '[v]' -map '[a]' \
  ace-ventura-reverse-reversed.mp4

MP3-to-MP4 or audio-to-video conversion using audio power spectrum filter

ffmpeg -i ace-ventura-reverse-reversed.mp3 \
   -filter_complex "showfreqs=s=640x320:mode=bar[v]" \
   -map '[v]' -map 0:a:0 \
   -vcodec mpeg4 -b:v 466k -r:v 24 \
   ace-freq.mp4

How to add echo to a video

ffmpeg -y -i barbara.mp4 \
  -filter_complex \
   "[0:a:0]atrim=start=0:end=5, asetpts=N/SR/TB[a1];
    [0:a:0]atrim=start=6:end=12,, asetpts=N/SR/TB, aecho=0.8:0.9:1000:0.3[a2];
    [0:a:0]atrim=start=13:end=16, asetpts=N/SR/TB[a3];
    [a1][a2][a3]concat=n=3:v=0:a=1[a]" \
  -map 0:v:0 -map '[a]' \
  -t 0:0:16 \
  barb-echo.mp4

Blurring a portion of a video

ffmpeg -y -i fallon.mp4 \
  -filter_complex \
    "[0:v]crop=220:220:340:20[cropped];
     [cropped]boxblur=6:6[blurred];
     [0:v][blurred]overlay=340:20[overlaid]" \
   -map '[overlaid]' -map 0:a -acodec copy \
   -ss 0:0:10 -t 0:0:10 \
  fallonbb.mp4

Write text on video

ffmpeg -y -i tl.mp4 \
  -filter:v \
    "drawtext=x=30:y=100:fontcolor=yellow:alpha=0.6:shadowx=7:shadowy=7:text='THEY LIVE:fontsize=112:fontfile=FingerPaint.ttf" \
  tlt.mp4

Render transparent GIF on video with infinite looping

ffmpeg -y  \
   -i fallon.mp4  \
   -ignore_loop 0 -i world.gif \
   -shortest \
   -filter_complex \
     "[0:v:0]overlay=300:60[v]" \
   -map '[v]' -map 0:a:0 -t 0:0:10 \
   -vcodec libx264 -acodec copy \
   beto-animated.mp4

Replace green-screen background on another video

ffmpeg -y -i fallon.mp4 -i van-damme.mp4  \
   -filter_complex \
     "[0:v:0]pad=1920:360[frame];         
      [frame][1:v:0]overlay=640:0[v1];
      [1:v]colorkey=0x008000:0.2:0.2[v2];
      [0:v:0][v2]overlay[v3];
      [v1][v3]overlay=1280:0[v4];
      [v4]scale=960:180[v];
      [0:a:0][1:a:0]amerge=inputs=2[a]" \
   -map "[v]" -map '[a]' \
   -ac 2 -t 0:0:20 \
   green-screen-eliminated.mp4

Fade into another video using a transition effect

ffmpeg -y -i beto.mp4 -i fallon.mp4 \
  -filter_complex \
    "[0:v:0][1:v:0]xfade=hrslice:offset=10:duration=6[v];
     [0:a:0]atrim=start=0:end=16, asetpts=N/SR/TB[a1];
     [a1][1:a:0]acrossfade=duration=6[a]" \
  -c:v libx264 -crf 31 -preset slow -pix_fmt yuv420p \
  -c:a libmp3lame \
  -map '[v]' -map '[a]' \
  beto-fallon-slice.mp4

Slow down a video

ffmpeg -y -i Laurie-Lennon-Original.mp4 \
  -filter_complex \
  "[0:v]setpts=PTS*1.1228[v];
  [0:a]atempo=0.8906[a]" \
  -map '[v]' -map '[a]' \
  Laurie-Lennon-Slow.mp4

Subtitle a video

ffmpeg -y -i duffy.mp4 \
   -filter_complex "subtitles=duffy.ass" \
   -c:a copy \
   -t 0:1:0  \
   duffys.mp4

In the subtitle file (SSA), I used the following style for using my own custom font and other subtitle display settings.

Style: Default,Florentia,30,&H2200CCCC,&H000000FF,&H220000EE,&HAA00CCCC,-1,-1,0,0,100,100,0,30.00,3,2,3,1,20,20,40,1

Acknowledgements & Thanks

"Rowdy" Roddy Piper/John Carpenter (They Live)
Amazing Lucas, Alaska Granny, Barbara 2.0, Sara Gonzales Unfiltered, Joking.com,
Laurie Lennon
Pamela Anderson/Yasmine Bleeth (Baywatch)
Jack Benny (The Jack Benny Program)
Jimmy Fallon (Tonight Show)
'Beto' O'Rourke
Jean-Claude Van Damme