HandBrake is a tool for converting video from nearly any format to a selection of modern, widely supported codecs. This support article will show you how to transcode your video file into an MP4 video file format, which is a great universal video format.
Download HandBrake here at https://handbrake.fr/
Steps to Transcode Videos Using HandBrake
1. Open HandBrake and Choose Your File
When HandBrake is opened, it will immediately ask which file desired for transcoding.
Choose the file and click Open. 
If it does not automatically ask for a file, click the Source button in the top left corner.
2. Choose The Output Format
Under Output Settings select MP4 from the Format drop down menu.
3. Choose The File Destination
For Destination click Browse and select where you want the MP4 stored upon completion of the transcoding process.
4. Lower Video Quality (optional)
If the source video file is large in file size, HandBrake can be used to compress the video quality. Click the Video tab and move the Constant Quality slider to the left. The further the slider is moved to the left, the more compressed the output video file will be. The default setting is at 20, which should yield a file size similar to the original. When set to 23, the size of our test video file was reduced by 20%. Feel free to experiment.
| Note: Do not touch the Audio tab, to compress the audio. The audio is what is most important for 3Play Media to transcribe videos. |
5. Click Start
Once the destination has been assigned, and any compression settings have been changed, the video is ready to be transcoded into an MP4.
Click Start to begin the transcoding process. 
Depending on the duration of the file, this can take some time. Once it has finished, it will be located in the folder selected for its Destination.
You now have successfully transcoded your video into an MP4!