Can Android v2.3 Play MP4 files?

I have an MP4 file that I play with the MediaPlayer example in API demos on the emulator. Only the sound is played. No video. Why would this be and how do开发者_JAVA百科 i get it to play?

BTW: .3gp files to play both audio and video in the same example.

Thanks!

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The supported media formats are listed here: http://developer.android.com/guide/appendix/media-formats.html . Make sure your mp4 file uses the right format (H.264 AVC or H.263).