Archive for November, 2007

AppleScript Code for Converting an AVI to an MP4 in QuickTime Pro

Monday, November 19th, 2007

Anther Simple Answer to a Specific Quesion:

As part of my ongoing obsession with converting and storing video on the Mac, one of the obvious tools I’ve looked at for converting from .avi files .mp4 files QuickTime. Assuming you can get your video to play (hint:, Quicktime Pro has an Export feature that produces very acceptable video using the H.264 codec.

Since there didn’t seem to be any mechanism for batch processing, I looked into using Applescript to automate the task. I found numerous examples online that almost did what I needed, but nothing that was exactly right. In every case, the format was wrong, and the script in question did way more than I wanted. So here’s the bare bones, stripped down AppleScript code for…

…saving MPEG4 export settings to an external file:

tell app "QuickTime Player"
    tell first movie
        save export settings for MPEG4 to file "Users:yourname:MPEG4 Settings"
    end tell
end tell

…and converting an .avi file to an .mp4 using a saved external settings file:

tell application "QuickTime Player"
    close every window
end tell
tell application "QuickTime Player"
    open "Data:Upload:Harvey Birdman - 4x02 - Incredible Hippo.avi"
    if (can export front movie as MPEG4) then
        set theTime to duration of front movie
        with timeout of theTime seconds
            export front movie to ("Data:Upload:Harvey Birdman - 4x02 - Incredible Hippo.mp4") as MPEG4 using settings file "Users:yourname:MPEG4 Settings"
        end timeout
    end if
end tell
quit application "Quicktime Player"

How Documentation Can Impede Development

Sunday, November 18th, 2007

I’ve had this noble desire to document my development work for a long time, but whenever I try, the first casualty always seems to be productivity.

One of the projects I’ve been working on for a while now, for example, is documentation on encoding DVDs and AVI files for iTunes/AppleTV. So far, I’ve documented my hardware setup, and the method I use for ripping and encoding DVDs, as well as tools I use to convert AVI files to compatible MP4 files. This documentation, though, only accounts for half, maybe a quarter of what I’ve implemented. I’ve got scripts for automating the converting process and moving the files back and forth between several computers, scripts for grabbing Plot, Relase Dates, Ratings and Posters from iMDB and automatically adding them to iTunes. I’ve got scripts for displaying parsing iTunes and uploading all that data to my web page, so I have remote access to view the movies in my collection.

None of this is documented yet. In fact, I find myself reluctant to continue to develop new features and new scripts because I don’t want the divide between the code and the documentation to grow any more than it already has. At the same time, the weight of the documentation is high, the desire do it is low, and the call of Oblivion is strong.

Doing nothing isn’t even a guaranteed method to preventing the Documentation Divide1 from growing. My windows system started to go south, so I was forced to buy a new computer ahead of a schedule (a shiny new Intel-basic Mac mini; I call it Cletus).

Not only does this render most of my existing documentation obsolete (or at least irrelevant), it means that my model changes from a cross-platform, Frankenstein style system running on multiple machines to an integrated application running on a single box. Development gets easier, new features are possible, and my audience goes from three people who happen to be running the same outdated, multi-cultural hardware setup as me to anyone running a halfway decent Mac. The gulf between what’s documented and what I’m running is wider than ever, and finally having the speedy new Mac I wanted probably means it will continue to grow.

… and maybe that’s the lesson here. When I started this blog, I made the slogan “The Blog is Not the Point” as a reminder to myself that this was a web log, and that my projects were more important than usage statistics, getting Dugg, or trying to generate ad revenue. That same slogan can be equally effective in reminding myself that I don’t have to wait for my blog to catch up with the code before I get back to work: the Blog is Not the Point.

  1. Someone make a note of the term “Documentation Divide”. If there isn’t already a phrase for this phenomenon, I want to nominate this. []