Unknown encoder 'libx264'

I installed ffmpeg 0.8.9 on ubuntu11 by

./configure --enable-gpl --enable-nonfree --enable-pthreads --enable-libfaac --enable-libmp3lame --enable-libx264

When I run it

ffmpeg -y -i test.mp4 -f mpegts -acodec libmp3lame -ar 48000 -ab 64k -vcodec libx264 -b 250k -flags +loop -cmp +chroma -partitions +parti4x4+partp8x8+partb8x8 -subq 5 -trellis 1 -refs 1 -coder 0 -me_range 16 -keyint_min 25 -sc_threshold 40 -i_qfactor 0.71 -bt 250k -maxrate 250k -bufsize 250k -rc_eq 'blurCplx^(1-qComp)' -qcomp 0.6 -qmin 10 -qmax 51 -qdiff 4 -level 30 -aspect 320:240 -g 30 -async 2 a.ts 

It said

Unknown encoder 'libx264'

(Note: the same error could occour with avconv)

How can I fix this? Thanks!

3 Answers

I am using Ubuntu 11.04, and I also came across this error - Unknown encoder 'libx264'. Installing the package libavcodec-extra-53 resolved the problem.

In Ubuntu 14.04 LTS the package that is needed is called libavcodec-extra-54 (and libav-tools)

start by installing these libraries

sudo apt-get install libfdk-aac-dev libass-dev libopus-dev \ libtheora-dev libvorbis-dev libvpx-dev libssl-dev 

For Ubuntu 20.04 issue

sudo apt-get install nasm 

and hop over this manual nasm install ... yet as of Ubuntu 17.04 sudo apt-get install nasm does not supply a new enough nasm so install that manually

get source for nasm at download the latest then

cd ~/src/nasm-2.13.02 # update to release you just downloaded ./configure make -j $(nproc) sudo make install 

Then for x264 :

git clone cd x264 ./configure --enable-static --enable-shared make -j $(nproc) sudo make install 

For mp3 get LAME (libmp3lame)

sudo apt-get install libmp3lame-dev 

or install manually from version v3.100, then give it the normal

cd lame-3.100/ ./configure make -j $(nproc) sudo make install 

Finally download ffmpeg source and do install :

git clone git:// cd ffmpeg ./configure --enable-gpl --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-nonfree --enable-shared --enable-openssl make -j $(nproc) sudo make install 

I feel your pain, but this works - still valid on Ubuntu 18.10

I got this error with Ubuntu 18 while using OpenAI Gym. You need correct versions of ffmpeg and x264 encoder. To get them, I used following and it worked:

conda install x264=='1!152.20180717' ffmpeg=4.0.2 -c conda-forge