Length of a folder with MP4 files

mp4du.sh

mp4sum() {
  TOTAL=0
  for x in $1/*.mp4
  do
    size=`mp4box -std -diso $x | grep 'TimeScale="1000"' | awk 'BEGIN{FS="\""};{ print $8 }'`
    TOTAL=`expr $TOTAL + $size / 1000`
  done
  x='obase=60;'$TOTAL
  print $x | bc
}

for x in *
for> do
for> print $x
for> mp4sum $x
for> done

http://www.catonmat.net/blog/wp-content/uploads/2008/09/awk1line.txt

http://stackoverflow.com/questions/1555173/gnu-awk-accessing-captured-groups-in-replacement-text
http://www.adp-gmbh.ch/unix/awk/
http://www.thegeekstuff.com/2010/01/8-powerful-awk-built-in-variables-fs-ofs-rs-ors-nr-nf-filename-fnr/