How to extract MOOV atom/metadata from MP4 file?
Maybe I'm a bit late, but I'd use bento4 mp4dump, it's really easy to install on mac with brew brew install bento4

mp4dump 1.mp4 

[ftyp] size=8+16
  major_brand = iso5
  minor_version = 200
  compatible_brand = iso6
  compatible_brand = mp41
[moov] size=8+740
  [mvhd] size=12+96
    timescale = 1000
    duration = 0
    duration(ms) = 0
....