Most of today's modern mobile phones have the ability to play MP4 video files. The hard part is to encode the video while maintaining the compatibility and optimising the video file for mobile phone playback. While video in 3GP container can be encoded using advanced codec (AVC/H.264 for example) and HE-AAC for audio, most of the 3GP files are encoded using H.263 for video and AMR-NB or AMR-WB for audio which is not very great compared with XViD and AAC in MP4.

Below are the steps to convert video files to MP4 for your mobile phones, while maintaining the compatibility.

1. Download and install MediaCoder. MediaCoder is a great free and open source transcoder for Windows.

2. Run MediaCoder, drag and drop the video files that you want to convert into MediaCoder. Then go to Extensions > Mobile Phones > Nokia N70. (It is not necessary to a Nokia N70 to play the MP4 files converted using this method. Read your mobile phone manual to see whether it can play MP4 video or not. Do some search on the internet if you lost the manual, Wikipedia might help you)

2. Press Yes.

3. You can choose the size of the video here (1) and the quality of the video (2). I recommend you just use the default settings since it is sufficient for most mobile phones.

4. Choose the output folder (3). Press start (4) to start the encoding process.

5. Encoding process is in progress. Wait for a few minutes for the process to finish, and then you can transfer the converted video to your mobile phone. The encoding speed is depend on your system speed.

6. The original video that I use in this post.

7. The converted video. It is blurry if you watch on your PC, but it is sufficient for your mobile phone. The final file size should be around 15MB for a 5 minutes video.

[MediaCoder] [Download: MediaCoder]