Posts Tagged ‘mac’

Convert NTSC video to PAL with smooth motion

Sunday, January 16th, 2011

When converting NTSC digital video to PAL the pixel aspect ratio needs to change from 720 x 480 (NTSC) to 720 x 576 (PAL). Depending on your project the more important problem is the transition from 29.97 (NTSC) frames per second to 25 (PAL).

I found Final Cut Pro and QuickTime both convert 29.97 to 25 frames per second by cutting the five extra frames to make it fit. This results in a loss of temporal resolution, making motion in the footage jerk and skip because the frames which created the illusion of motion are missing.

There are a few commercial applications that can convert NTSC to PAL with smooth motion, but I followed advice on this forum which suggested using Compressor for the standards conversion:

  1. Export an NTSC Quicktime movie from Final Cut Pro without compression
  2. In Compressor, select a DV PAL preset
  3. Turn on Frame controls and set resizing and retiming to “better” or “best.”
  4. Run Compressor. This took >3 hours for 12 minutes of uncompressed footage.

This should give you a 720 x 576 (PAL CCIR 601) with 25 frames per second. Finally, in DVD Studio Pro make sure you choose PAL before you import any footage, and leave all the regions selected which is the default.

UNIX: List open files

Saturday, January 15th, 2011


Can’t eject a CD or unmount an external hard drive on your mac because of this error: The disc is in use and could not be ejected. Try quitting applications and try again.?

This UNIX command reports a list of all open files and applications that opened them. Open Terminal and replace the name of your volume below to test.

$ lsof | grep /Volumes/media/

Thanks

Addendum: Here’s an even more helpful command: eject the disk with UNIX when the GUI won’t allow it.

$ diskutil eject [Mount Point|Disk Identifier|Device Node]

Oh, and a final tip nestled in this addition: If you have a space in the name (for example you had two disks mounted named “backup” and OSX named the second one to mount “backup 1”) then you can easily reference the name (or any file or directory name with a space) with a backslash which “escapes” the character. Typing the first few characters and then type the tab key will do it automatically.

$ diskutil eject /Volumes/backup\ 1/