I was having the hardest time getting various programs to echo the runtime of m2ts files in Linux, and it turns out someone wrote a parser for the files in the BDMV/PLAYLIST directory, which have all of this information.

• Get bdtools. I got Version 1.4. You can find it here.
• ./configure && make && sudo make install
• Try running mpls_dump. I got this error when running:

  mpls_dump: error while loading shared libraries: libbd-1.0.so.1: cannot open shared object file: 
  No such file or directory

• To fix it, do this:

  echo "/usr/local/lib" | sudo tee -a /etc/ld.so.conf
  sudo ldconfig