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Echo Fire and Digital Audio Applications

One of the most popular uses of the LiveFire (FireWire Routing) feature of Echo Fire for Macintosh is to provide a way for digital audio applications such as ProTools to output QuickTime compressed video files to a real video monitor. This frees up space on the computer monitor and provides a better client viewing experience, without requiring a PCI-bus slot and without adding a lot of PCI-bus traffic to your system.

We've collected a series of tips and tricks for getting the best results when using Echo Fire in this application.

Digitizing Video for Use with Echo Fire FireWire Routing

In order for Echo Fire to route a video file out the FireWire, the file must be in the correct format. There simply isn't enough time to convert the video on-the-fly (it would involve a CPU-hungry decompression/compression cycle), so the video needs to be ready to be sent directly to the FireWire hardware.

Echo Fire expects a QuickTime movie using a frame size of 720x480 (NTSC) or 720x576 (PAL) and the Apple DV codec.

If you are having difficulty with a specific movie and you're not certain of its format, open the movie file in QuickTime Player and do a Get Info (command + i) and QuickTime Player will display the movie format, which should be either "DV - NTSC, 720 x 480, Millions" or "DV - PAL, 720 x 576, Millions". If your movie file is in any other format, Echo Fire will not recognize it as something to route to the FireWire.

There are many programs that can capture QuickTime movies in the correct format, such as Premiere, Final Cut Pro, and iMovie. If you don't have one of these programs already, we recommend a shareware capture program called BTV Pro, which is available from www.bensoftware.com.

If you are using iMovie to perform your captures, be sure to export the captured footage as a QuickTime Movie and not a DV Stream. A DV Stream will appear to work, but may drop frames or freeze occasionally during playback.

Video Playback Performance Issues

One of the advantages of using Echo Fire and FireWire for displaying your video is that it places a relatively small load on the system, leaving resources available for your audio application. However, many systems doing primarily audio work may already be near their maximum limits, and adding any other tasks at all may cause performance issues. But there are several things to check before simply assuming that your system isn't up to the task:

  • Check to be sure that the video file you are attempting to play is in the correct format, as described above. In particular, if you are using a DV Stream (instead of a QuickTime Movie), things will appear to work, but performance will be poor, with occasional freezing of the video playback.
  • Make sure that the window on the computer monitor which shows "Video Routed to FireWire" is fully on the screen, with no parts of the window off the edge of the display.
  • Make sure that your computer monitor is set to "Thousands" or "Millions" of colors.
  • Sustained FireWire video playback requires a disk capable of around 4 MB/second sustained read performance. This is well within the ability of a modern Mac G4 with IDE drives. However, using the same disk for both video and audio, or using slower FireWire or USB drives, may not be able to sustain that data rate.

Converting Existing Video Files to Echo Fire-Compatible Format

Many times you will have existing digitized video files you will want to use with Echo Fire. If you have the tapes available, the fastest solution will usually be to simply recapture the video in the correct format, as discussed above. But if you don't have the tapes, it is possible to recompress an existing video file using QuickTime Pro, the $30 upgrade to Apple's QuickTime software.

To convert an existing file, open it in QuickTime Player Pro. Choose Export from the File menu, or press command + e. In the dialog that appears, choose "Movie to QuickTime Movie" in the Export popup. Then click the Options button.

In the Options dialog, make sure that the Video box is checked, then click Settings. Choose "DV - NTSC" or "DV - PAL" (as appropriate) as the Compressor, then click OK. Click the Size button. Select "Use custom size" and enter a width of 720 and a height of either 480 (NTSC) or 576 (PAL). Click OK.

Make sure that Sound is checked. Click Settings and set the Compressor to None and the Rate to either 32 or 48 kHz. The Size should be 16-bit Stereo. Click OK.

Click OK in the Movie Settings dialog. Enter a filename for the newly converted movie, and click Save. The export process will now begin. Depending on your system speed and the format of the original file, this may be a slow process.

Note that converting video this way will result in a loss of video quality compared to capturing the video footage directly into DV format.

Resizing the Computer Screen Video Playback Window

In audio applications which allow you to resize the video playback window on the computer screen (such as MOTU Digital Performer), you can make the playback window as small as you like. Since it will only be displaying "Video Routed to FireWire", there is no need to have it taking up a lot of screen space. You must, however, keep the window open and fully on screen.

In applications, such as ProTools, which don't allow you to resize the window, there is still an easy way to make the window smaller. Open the movie file in QuickTime Player Pro. Resize the window which appears on the screen by dragging the lower right corner of the movie window. Make it as small as you like. Then simply save the movie by choosing Save from the File menu, or pressing command + s. The only data being saved is the new window size, so this is a very quick operation. From now on, when you open this movie file in ProTools, it will open in a window with the new, smaller, size.

In order to be able to save the QuickTime movie, you will need QuickTime Pro, the $30 upgrade to QuickTime available from Apple.


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This page was last updated Saturday, August 3, 2002.