How can I play PC video on my Nokia cellphone?

[I do have a clue, luckily, and that clue is called Nokia Smartphone Hacks, a cool book full of slick tricks like this from Michael Yuan. With the permission of the publisher, I'm reproducing Hack #71: Play PC Video Clips on the Phone. --DT]

Watching video on your mobile phone is cool! Once considered the killer application for broadband wireless networks (e.g., 3G networks), mobile video holds great promise for a whole new mobile lifestyle, with the mobile phone as your entertainment center. If you have a Nokia phone, you can probably watch a lot of video on your device today. Most recent Nokia Series 40 and Series 60 phones, regardless of whether they have cameras, support playback of 3gpp-format video files. The default video player on Nokia Series 60 phones is the Symbian version of RealPlayer.

TIP: An undocumented feature in RealPlayer on Series 60 phones is that you can use the navigation keys (a.k.a. joystick) to fast forward or rewind the movie. Up is fast forward and Down is rewind. You cannot do this with the Nokia video player on Series 40 phones.

Most existing video files are not in the 3gpp format. They need to be resized and re-encoded for mobile phone video players.

Use QuickTime Pro

If you are using a Windows or Mac OS X computer, QuickTime Pro is the best editing tool for video content. You can open any video file and save it as a 3gpp file. Figure 11-12 shows the conversion process.

Figure 11-12. Converting a PC/Mac movie file to 3gpp format for phone playback in QuickTime Pro

Clicking the Options button, you can bring up the dialog box for 3gpp movie export. Figure 11-13 shows the video options. You can choose the video size for Series 40 (128 x 96 pixels) or Series 60 (172 x 144 pixels) phones. The data rate setting is used to limit the size of the final video file. The low data rate gives you smaller files but also lower video quality (e.g., skipped frames and mosaic effects).

Figure 11-13. The 3gpp video export options in QuickTime Pro

Figure 11-14 shows the audio options of the exported 3gpp movie. Most Nokia phones can only play mono audio via the phone speaker or headset. If that is the case for your phone, make sure you export the movie audio as "mono" to save space.

Figure 11-14. The 3gpp audio export options in QuickTime Pro

For each video file, you have to search for the best compromise of data rates. Table 11-1 lists the data rate settings I typically use. I found them able to produce movies that are of reasonable quality and yet are still small enough to fit into a typical MMC card.

Table 11-1. Example settings for exported 3gpp movies

TIP: Feature-length movie files are much larger than the 4MB size limit imposed by the phone memory. To transfer movie files to the device via Bluetooth, you need to configure the device message Inbox to save received messages in the MMC card [Hack#21].

The 3gpp standard provides mechanisms for content providers to limit how the user uses the 3gpp movie on the phone (a.k.a. DRM protection controls). For instance, you can forbid the user to forward the movie from the phone, or limit the number of times the movie can be played on the phone. Figure 11-15 shows such options supported by QuickTime Pro.

Figure 11-15. The 3gpp advanced options in QuickTime Pro

Use FFmpeg

If you use Linux or prefer a free cross-platform command-line tool, the open source FFmpeg program is best. You can specify the video size, frame rate, data rate, and other configuration options on the command line.

The preceding command converts the movie.avi file to a 3gpp file. The video is resized to 172 x 144 to match the Series 60 screen. The frame rate is 10 fps. The audio track is set to be mono (-ac 1). The data rates are 48 kbps for video and 12 kbps for audio.

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