How to convert .mp4 videos to .j2k format.
Converting MPEG-4 Videos directly to JPEG 2000 Images (.mp4 to .j2k conversion) might perhaps be possible, even though your options are limited.
Try using media editing programs or (online) conversion tools, such reaConverter or Filestar, which should allow users to import MP4 videos and export them in J2K format.
A file conversion and management software.
A popular burning and multimedia suite from Nero
A dedicated conversion software