Avconv is an open source package used of fast video and audio converter including grab from a live audio/video source, also can be convert between arbitrary sample rates and resize the videos.

Basic Process of Avconv

Install basic packges before go to prceed further steps,

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

Note : Do you need latest version snapshot use http://libav.org/releases/libav-snapshot.tar.bz2

Download the package using wget command and extract that tar file,
#  wget http://libav.org/releases/libav-10.1.tar.gz

#  tar -xvzf libav-10.1.tar.gz

#  cd libav-10.1

Configure the packages as you need,
# ./configure --extra-cflags=-I/opt/local/include --extra-ldflags=-L/opt/local/lib --enable-gpl --enable-version3  --enable-libvpx

# make

# make install

INSTALL libavcodec/dv_profile.h
INSTALL libavcodec/dxva2.h
INSTALL libavcodec/vaapi.h
INSTALL libavcodec/vda.h
INSTALL libavcodec/vdpau.h
INSTALL libavcodec/version.h
INSTALL libavcodec/xvmc.h
​# whereis avconv
avconv: /usr/local/bin/avconv

For more help:
# man avconv