2006-02-22

Chaptify

I had amazing functionality within reach since iTunes 4.9 and I didn't even know it. This goodness I speak of is the ability to enhance AAC files.

I'm sure to many of you, this is old news, but this slipped right by me. Earlier this week, I was listening to a podcast from Sasha that I found while browsing the podcasts on iTMS. I happened to look down and noticed a bunch of vertical lines in the time bar for the mix.




I quickly found that I could skip back and forth between tracks within the mix. I was elated. I'm pretty new to the podcasts, so I had never seen this before. After some googling, I found that what I was seeing, was an enhanced podcast. Enhanced podcasts allow you to do all sorts of cool things like set images, make chapters, add text pages, and even embed web links.

The items I found most intriguing were the chapter markers and notes page that could be displayed on my iPod.

I have been wishing for things like this for years. The chapters could allow me to break up long mixes and effectively remove the need for gapless playback. The notes page would allow me to include setlists and other useful information and have it just a couple of button pushes away, instead of in a text file loaded off under the notes menu item as I currently do.

Further googling led me to discover that Apple has released a command line tool for adding enhanced podcast content to AAC files. The tool is called ChapterTool (sorry, Mac only) and you can find a good collection of info about it over at the VoxMedia wiki. I grabbed ChapterTool and it is great. All you have to do is create a simple XML file describing the chapter cuts and specifiying any pictures and links you'd like to embed. Then point ChapterTool at your XML and source AAC and boom, enhanced goodness.

At first, I wasn't sure I could enhance anything but a podcast. Sure, a podcast is no more than a specially wrapped audio file, but I didn't know how iTunes/iPod would handle it. To test it out, I decided to enhance my recent DJ Mix, Hot Winter. Enhancing it allows me to add track infomation and allow skips between tracks, within the set. Here is a tast of the XML that I used.

<chapters version="1">
<chapter starttime="00:00">
<title>James Zabiela - Robophobia</title>
<picture>pictures/hot_winter.jpg</picture>
</chapter>
<chapter starttime="07:15">
<title>John Kelley - Force Ten</title>
</chapter>

It worked great. You can enhance "regular" files, they don't have to be podcasts. Apple should be making a big deal about this feature. Do other players on the market support this kind of thing? Apple should commission DJs to mix tracks from the iTMS and make them available at a reduced cost. These would be enhanced with album art for the individual tracks and would include iTMS links to the tracks. As you are listening on your computer, when you hear something you like, you simply click the hot link on the left and you can go buy that track. I guarantee that amateur DJs are going to make use of this. The professionals might as well be doing it too.

Back to the experiment. Within a few minutes, I had all of the enhancements added. I'm going to have to take this further. My next task is to write an app to take an AAC and a CUE file and automagically add the cuts and track info. I desperately need something like this to make the sets I grab from Hybridized.org that much better. As it is now, when I'm listening to one of these, I have to keep a browser open to the setlist. I haven't yet figured out how to add a text page like in the Sasha podcast, but I'm still looking :)

Finally, for your listening (and chapter mark testing) pleasure, I present, enhanced Hot Winter. If you don't have an iPod that can make use of the enhancements, be sure to try it out in iTunes. You'll get an extra button at the top that drops down to show the track info.

2 comments:

matt said...

Did you ever write an app to take an AAC and a CUE file and automagically add the cuts and track info?

matt said...

BTW, you can use my cue2chapters tool to convert a .cue sheet to a ChapterTool .xml file and then use something like AudioBinder to import it and an AAC (.m4a) file and spit out a chapterized file.