How to compile FFMPEG with h.265, h.264 and vp9 support on CentOS
You should install the latest nasm version using yum by adding the repository:
yum-config-manager --add-repo http://www.nasm.us/nasm.repo
Then:
yum install nasm
This gives you nasm ≥ 2.13.
With this, the rest of the ffmpeg guide should work. I updated the guide on the FFmpeg Wiki, too.
If you like to compile things yourself:
curl -LO https://www.nasm.us/pub/nasm/releasebuilds/2.13.01/nasm-2.13.01.tar.gz
tar xzvf nasm-2.13.01.tar.gz
cd nasm-2.13.01
./configure --prefix=/opt/nasm
make
sudo make install
export PATH=/opt/nasm/bin/:$PATH