01_ffmpeg

Example code

Typical video conversion command:

ffmpeg -hide_banner -loglevel warning -i input.webm \
-c:a aac -b:a 128k \
-c:v libx264 -b:v 1000k \
-s 1920x1080 -r 25 output.mp4

remove audio from file:

ffmpeg -i 1.mp4 -c copy  -an out.mp4

Video to audio

ffmpeg -i 1.mp4 -vn out.mp3

speed up/down:

speed up video only:

ffmpeg -i 1.mp4 -vf "setpts=PTS/10" output.mp4

speed up audio only:

ffmpeg -i input.mp4 -af "atempo=1.1" out.mp4

you can use both flags together

concat file from file list:

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

content of list .txt:

file '/home/davood/Desktop/video/out.mp4'
file '/home/davood/Desktop/video/out2.mp4'

remove extra text:

ffmpeg -hide_banner ...

use cuda:

ffmpeg -hwaccel cuda ...

just copy audio:

ffmpeg -c:a copy ...

just copy video:

ffmpeg -c:v copy ...

set audio container to AAC and bitrate to 128k:

ffmpeg -i input.mp4 -c:v copy -c:a libfdk_aac -b:a 128k output.mp4

it might not work in windows, so use built-in AAC:

... -c:a aac ...

set video container to H.264 and bitrate to 1MB/s:

ffmpeg -i input -c:v libx264 -c:a copy output.mp4

two pass encoding:

Windows users should use NUL instead of /dev/null and ^ (in command prompt) or ` (in PowerShell) instead of .

ffmpeg -y -i input -c:v libx264 -b:v 2600k -pass 1 -an -f null /dev/null && \
ffmpeg -i input -c:v libx264 -b:v 2600k -pass 2 -c:a aac -b:a 128k output.mp4

change dimension:

ffmpeg -i input.mp4 -s 1920x1080 output.mp4

change frame rate:

ffmpeg -i input.mp4 -r 25 output.mp4

rotation:

ffmpeg -i in.mov -vf "transpose=1" out.mov

0 = 90CounterCLockwise and Vertical Flip (default)
1 = 90Clockwise
2 = 90CounterClockwise
3 = 90Clockwise and Vertical Flip

cut a part of file:

//// with start and stop time:
ffmpeg -i input.mp4 -ss 00:01:00 -to 00:02:05 output.mp4

//// with start and duration(in seconds):
ffmpeg -i input.mp4 -ss 00:01:00 -t 100 output.mp4

//// from second 3 to end:
ffmpeg -i input.mp4 -ss 3 -c copy output.mp4

set encoding preset:

... -preset ultrafast ...
... -preset veryslow ...

set quality

greater numbers lead to less quality and size (constant rate factor):

... -crf 23 ...

set lossless H.264:

... -qp 0 ...

restict CPU usage

to use 2 cores:

- threads 2

Log levels

ffmpeg -loglevel <LEVEL>

defaul level is warning. available log levels, from less info to more info:

quiet
panic
fatal 
error 
warning 
info 
verbose 
debug

Make a video form a list of images

ffmpeg -framerate 10 -pattern_type glob -i '*.png' -c:v libx264 -pix_fmt yuv420p output.mp4

Convert images

ffmpeg -i input.png output.jpg

changing quality:

-q:v 2: sets the quality of the output JPEG. The value can range from 2 to 31, where 2 is the highest quality and 31 is the lowest.

ffmpeg -i input.png -q:v 2 output.jpg

Using percentage based compression

ffmpeg -i input.png -compression_level 100 output.jpg

changing size:

ffmpeg -i input.png -vf "scale=iw*0.5:ih*0.5" output.jpg

reference

reference on presets and encoding