Mobile Video: Working with MPEG-4 Clips on Mobile Phones
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Creating 3GPP Video

Finally, there's moving movies in the other direction--converting your own video clips to 3GPP format to download and play on mobile phones (and other fun gadgets).

Again, QuickTime Pro provides an easy and handy solution--just choose to export as "Movie to 3G," and choose your desired format:

• Video
  • MPEG-4
  • H.263
  • H.264
• Size
  • 96 by 80
  • 128 by 96 SubQCIF
  • 176 by 144 QCIF
  • 320 by 240 QVGA
• Frame Rate
  • 8
  • 10
  • 12
  • 15
• Audio
  • AAC-LC (Music)
  • AMR-NB (Music)
  • QCELP (Speech)

To make this a bit easier, QuickTime Pro offers general presets for both 3GPP and 3GPP2 (only 3GPP2 enables the lowest 96 by 80 resolution and QCELP audio).

There are also specific presets for three profiles: 3GPP (Mobile MP4) and 3GPP2 (EZmovie) at 176 by 144 and 15 fps with AMR-NB audio, and AMC (EZmovie) at 128 by 94 and 7.5 fps with QCELP audio.

QuickTime Pro, 3G Export Settings dialog for exporting to 3GPP and 3GPP2 formats

Unfortunately, the mobile carriers and handset manufacturers are not particularly focused on this kind of use for their devices, and do not provide handy documentation of supported formats in these technical terms. You'll have to experiment to see what works on your specific device, obviously starting with what you learn from examining the properties of files captured on your camera phone.

And don't forget your other devices that create and play MPEG-4 files. For example, you can use your digital camera as a portable video player by downloading clips to the memory card. These are more likely to be basic MPEG-4 files, not 3GPP (for mobile phones) or the new H.264/AVC version.

Besides the 3GPP formats, QuickTime Pro provides a variety of export options for MPEG-4 video:

• Video
  • MPEG-4 Basic
  • MPEG-4 Improved
  • H.264
• Size
  • 160 by 120
  • 176 by 144 QCIF
  • 320 by 240 QVGA
  • 352 by 288 CIF
  • 640 by 480 VGA
  • 720 by 576 SD
  • 1280 by 720 HD
  • 1920 by 1080 HD
• Audio
  • AAC-LC VBR (Music)
  • AAC-LC (Music)
  • CELP (Speech)

It also provides a preset for the ISMA version of MPEG-4--the Internet Streaming Media Alliance is another industry alliance developing standards for streaming rich media.

Tiny Clips

MPEG-4 has been slow to gather momentum as a widely supported format, delayed by licensing issues and the process of gathering industry consensus though a standardization process. Meanwhile, commercial alternatives, including Microsoft Windows Media and Real Networks RealVideo, have leapt ahead with concentrated efforts in compression technology, efficient implementations, marketing promotion, and commercial implementations. MPEG-4 now is catching up with the new improved H.264/AVC codec, and Apple's leadership with QuickTime 7.

But less visibly, tiny MPEG-4 files have been infiltrating our devices over the past few years, appearing in digital cameras, camcorders, and now mobile phones. However, these have been little more than cute little curiosities, with such short low-resolution clips, and the difficulty of doing anything more with the MPEG-4 format.

Now the possibilities are opening up. Better lenses and larger-capacity cards make it more reasonable to shoot higher-resolution and longer clips. Mobile phones make it easier to shoot and share these clips, and memory cards and Bluetooth make it more reasonable to move them around. And stronger support for MPEG-4 and 3GPP formats in tools like QuickTime Pro make it possible to edit these clips in with other kinds of footage.

Just as streaming video has exploded beyond its origins as choppy postage-stamp videos, these tiny MPEG-4 clips are growing into a more interesting part of our multimedia lives.

Doug Dixon is an independent technology consultant, author, and speaker specializing in digital media.

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