How to install libav/avconv on Mac OS X or macOS 11?

Question

OSX comes with a command line video conversion utility avconvert but this tool provides limited functionality compared to the avconv provided by libav.

How can I install avconv on OS X (or macOS 11)?

Answer 1

Just install it with brew:

brew install libav

Answer 2

First grab the library:

 wget http://libav.org/releases/libav-10.1.tar.gz
# use http://libav.org/releases/libav-snapshot.tar.bz2 for the latest snapshot
tar -xvzf libav-10.1.tar.gz 
cd libav-10.1

Set up the dependencies with MacPorts (or other package managers such as Homebrew):

sudo port install yasm zlib bzip2 faac lame speex libogg libvorbis libtheora libvpx x264 XviD openjpeg15 opencore-amr freetype

Build libav:

./configure \
--extra-cflags=-I/opt/local/include --extra-ldflags=-L/opt/local/lib \
--enable-gpl --enable-libx264 --enable-libxvid \
--enable-version3 --enable-libopencore-amrnb --enable-libopencore-amrwb \
--enable-nonfree --enable-libfaac \
--enable-libmp3lame --enable-libspeex --enable-libvorbis --enable-libtheora --enable-libvpx \
--enable-libopenjpeg --enable-libfreetype --enable-doc --enable-gnutls --enable-shared

make && sudo make install

Then you can run avconv:

avconv -i input.avi -c:v libx264 -preset slow -crf 18 output.mp4

---

• x264 +asm seems to be required to get working cpu-capabilities, so if you don't get them (ie. [libx264 @ 0x7fe66101a800] using cpu capabilities: none!) run:

sudo port upgrade --enforce-variants x264 +asm

You should get sth like: [libx264 @ 0x7fc62401b600] using cpu capabilities: MMX2 SSE2Fast SSSE3 FastShuffle SSE4.2 AVX

Answer 3

For those without brew - and until macports come up with a port for libav, here are my notes for installing libav on OSX 10.8.5 from source (libav version 12_dev0, from github).

The main problem I faced was that libav uses sem_timedwait() (semaphore.h in linux) which is not defined in macos.

This post https://stackoverflow.com/a/15163760 mentions that Keith Shortridge of the Australian Astronomical Observatory's software group (thanks) have written an implementation of said function for macos which can be found here https://github.com/attie/libxbee3/tree/master/xsys_darwin

Download the two files into ${LIBAVDIR}/libavdevice and then add the following line in the header file sem_timedwait.h:

int sem_timedwait(sem_t *sem, const struct timespec *abs_timeout);

Then edit the Makefile in ${LIBAVDIR}/libavdevice and add sem_timedwait.o at the end of the OBJS variable

configure and make all

you are good to go.

for the record, I used the following configure command:

./configure --extra-cflags=-I/opt/local/include --extra-ldflags=-L/opt/local/lib --enable-gpl --enable-libx264 --enable-libxvid --enable-version3 --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-nonfree --enable-libfaac --enable-libmp3lame --enable-libspeex --enable-libvorbis --enable-libtheora --enable-libvpx --enable-libopenjpeg --enable-libfreetype --enable-doc --enable-gnutls --prefix=/opt/local

WARNING: I can not say or guarantee whether the said implementation of sem_timedwait() is the correct one and/or will have no side-effects to the working of libav or indeed any other part of the system which links to libav libraries which have now a sem_timedwait() implementation in there!!!! For the latter may I suggest renaming sem_timedwait() everywhere in your copy of libav and Keith's implementation. Also check if any other symbols are exported from sem_timedwait.o and rename them also.

Here are the new, renamed symbols from Keith Shortridge's implementation of sem_timedwait():

sem_timedwait_keith, timeoutThreadMain_keith, triggerSignal_keith, ignoreSignal_keith, timeoutThreadCleanup_keith

(remove _keith to get the original names). The only reference to sem_timedwait() in libav (for said version) is in jack.c.

Answer 4

For videos hosted on https (many, these days), make sure you build avconv with OpenSSL support:

brew install libav --with-openssl