ImportError: libavcodec.so.56: cannot open shared object file: No such file or directory

Question

I was installed opencv with pacman, when i try to import opencv, i have this error:

>>> import cv2
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: libavcodec.so.56: cannot open shared object file: No such file or directory

how can I fix this error?

EDIT

sudo pacman -Ss libav
extra/gst-libav 1.4.4-1 [installed: 1.4.1-1]
    Gstreamer libav Plugin
extra/libavc1394 0.5.4-2 [installed]
    A library to control A/V devices using the 1394ta AV/C commands.
community/ffms2 2.20-2 [installed]
    A libav/ffmpeg based source library and Avisynth plugin for easy frame
    accurate access

Solution 1

This means that you don't have the correct libraries installed. Try a search using pacman -Ss libav.

On OpenSuSE this is part of libavcodec52 which says that it is related to ffmpeg. Check if you have ffmpeg installed at well as dependencies should pull in libavcodec.

EDIT

After reading the arch documentation, it looks like ffmpeg does provide the libavcodec requirement.

Solution 2

Same issues faced on centOS when checking the ffmpeg packages are installed and version :

 #/usr/local/bin/ffmpeg
/usr/local/bin/ffmpeg: error while loading shared libraries: libavdevice.so.56: cannot open shared object file: No such file or directory

or

# ldd `which ffmpeg`
    linux-vdso.so.1 =>  (0x00007fffb32d8000)
    libavdevice.so.56 => not found
    libavfilter.so.5 => not found
    libavformat.so.56 => not found
    libavcodec.so.56 => not found
    libpostproc.so.53 => not found
    libswresample.so.1 => not found
    libswscale.so.3 => not found
    libavutil.so.54 => not found
    libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f75f2ef8000)
    libm.so.6 => /lib64/libm.so.6 (0x00007f75f2c74000)
    libc.so.6 => /lib64/libc.so.6 (0x00007f75f28df000)
    /lib64/ld-linux-x86-64.so.2 (0x00007f75f3126000)

Solution:

Now, check the library path, open ld.so.conf

# vim /etc/ld.so.conf
include ld.so.conf.d/*.conf
/usr/local/lib
/usr/lib

Finally save and quit :wq!

Now, check with same command,

# ffmpeg -v
ffmpeg version N-73873-gcee7acf-syslin Copyright (c) 2000-2015 the FFmpeg developers
  built with gcc 4.4.7 (GCC) 20120313 (Red Hat 4.4.7-11)
  configuration: --enable-shared --enable-nonfree --enable-gpl --enable-pthreads --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libfaac --enable-libmp3lame --enable-libtheora --enable-libvorbis --extra-libs=-lx264 --enable-libxvid --extra-cflags=-I/usr/local/cpffmpeg/include/ --extra-ldflags=-L/usr/local/cpffmpeg/lib --enable-version3 --extra-version=syslin --enable-libass --enable-libvpx --enable-zlib --enable-gpl
  libavutil      54. 28.100 / 54. 28.100
  libavcodec     56. 50.101 / 56. 50.101
  libavformat    56. 40.101 / 56. 40.101
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 25.100 /  5. 25.100
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  2.101 /  1.  2.101
  libpostproc    53.  3.100 / 53.  3.100

Comments

[Vahid Kharazi]

@SailorCiro see my edit

[SailorCire]

@28 So it doesn't look like it is installed, unless it is in ffms2. Hmm...What is the output of ldconfig -v | grep libavcodec.so?

[Vahid Kharazi]

ldconfig: Path `/usr/lib64' given more than once ldconfig: Can't stat /usr/libx32: No such file or directory libavcodec.so.55 -> libavcodec.so.55.69.100

[SailorCire]

@28 So, you have libavcodec version 55 and you need libavcodec version 56.

[Vahid Kharazi]

how i can update it? or install 56 v?

[SailorCire]

@28 best answer is to wait until someone updates the package; however, you could download and compile by yourself. I don't recommend it. I recommend asking one of the maintainers about this