As of version 1.0a8, the Macintosh version of ViewMovie supports URL Tracks: a QuickTime movie can contain a track with URLs and target window specifications spaced out over time, and as the movie plays, ViewMovie will invoke the URL from Netscape. Due to limitations in QuickTime for Windows, URL Tracks will not be supported on that platform.

How do I create them?

URL Tracks require QuickTime 2.1, and take advantage of two key features: the improved text import functionality, and the ability to name tracks. URL Tracks are actually standard QuickTime text tracks that have been extended to support URLs. Be forewarned, while it's not horribly hard, it is pretty involved. Let's walk through a sample:

• If starting with an existing movie, open it in MoviePlayer 2.1. Open the Get Info window (under the Movie menu), and use the right popup menu to show the Time panel. Shuttle through the movie, and take note of the value of the "Current Time" display as you reach the points where you'd like a URL to pop up.

  

  In this walk-through, let's say you want to put a URL reference to "http://quicktime.apple.com/" at 30 seconds, one to "http://home.netscape.com/" at 1 minute and 20 seconds, and "http://www.well.com/user/ivanski/" at 2 minutes and 10 seconds.

• Create a text file using the Text Descriptor syntax as described in the QT 2.1 documentation. Text Descriptors are a simple text markup language that allows you to specify charateristics (most usefully time stamps) for text to be imported into a QuickTime text track. Here's an example, based on the previous discussion. Note the key portions affecting URL tracks:
  • The text file must start with the tag {QTtext}.
  • The timestamp format is [HH:MM:SS.FFF], where HH are hours, MM are minutes, SS are seconds, and FFF are the fractional portions of the seconds.
  • Use the {timeScale:} tags to specify the units that the fractional seconds in the timestamps will be expressed. For example, a timeScale of 30 specifies that each fraction is one-thirtieth of a second; thus, the timestamp [00:00:25.15] specifies 25.5 seconds (15/30=0.5).The parser is very picky. If the timescale you specify requires that you use two digits for the fraction (i.e., timescale=100, with fractions ranging from 00 to 99), always use two digits, adding a leading zero if necessary.
  • You may find the {timeStamps:} tag handy; it allows you to specify whether the timestamps are absolute or relative. That is, with {timeStamps:absolute} each timestamp specifies an absolute time (relative to time zero); with {timeStamps:relative} each timestamp specifies a time relative to the previous timestamp (one could also say that in this case each timestamp specifies the duration).
  • Insert the time stamps in the text file, followed by the URL information in the following format: <VMURL HREFABS=theHREF TARGET=theTarget>. The required HREFABS parameter works just like ViewMovie's and has the same restrictions (the URL must be absolute). The optional TARGET parameter allows you to specify a named Netscape target for the URL, whether a window or a frame. If unspecified, it will use "_current", which means that the current URL will be replaced by the one specified (and the movie will likely go away). Needless to say, use of TARGET is strongly encouraged.
  • Make sure you insert a final dummy timestamp after your last URL - otherwise, that last URL will last for, oh, zero seconds or so, and will never come up. Again, see the example.
  • Finally, another neat feature is that you can use the {language:} tag to specify the language for the URL track - thus, when the movie is ran under, say KanjiTalk, the user could get a different set of URLs, or different pacing altogether. Note that the {language:} tag expects as a parameter the language numberas defined in the MacOS.

  You can also take a look at another Text Descriptor example (the one used for the visible text in the demo movie) to get a better idea for the syntax; the best thing, however, is to get a hold of the QuickTime 2.1 docs.

• Use MoviePlayer's Import (under the File menu) to import the text file. Select the file and click on Convert..., and when presented with the Save dialog box, click on the Options... button to display the following window:

  

  In most cases you will want to force the size to be 0x0, although leaving the size intact is useful for testing purposes, since it allows you to see the URLs displayed as the movie plays.

• With your newly converted movie frontmost, open the Get Info window; use the left popup menu to display the characteristics for your newly created text track, and use the right popup menu to display the "General" settings panel. Change the track's name to something starting with "__VMURLTrack" - this is used by ViewMovie to distinguish URL Tracks from normal text tracks.

  

• Select the entire duration of the movie using either the controller or the Select All command under the Edit menu, and use the Copy command to copy the movie to the clipboard.
• Open the movie to which you wanted to add the URL timestamps. Use the Add command to paste your URL movie without shifting your original movie around. The Add command is found under the Edit menu when the option key is held down.
• Save the movie. You be done. When ViewMovie opens that movie, it will detect the track you just created and bring up the specified URLs.

Why only on the Mac?

The subset of QuickTime available for Windows is not sufficient to support URL Tracks; apologies.

Can I see them work?

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