What is difference between MKV and MP4?

Problem of Converting MKV to MP4 with Handbrake?

• Hello, I am trying to convert a 720P MKV (AC3) file to MP4 with Handbrake. It did the conversion smoothly but the converted video (h.264/mp4) is not intact. MP4 file picture looks great, but the sound is as if every other word is missing. BTW, I’m using HB to convert AVI to mp4 conversion works easily but why does it struggle with the mkv files?

• Answer:

  I finally figured out how to convert mkv to mp4 using Handbrake. Instead of using the Apple presets I now use the Normal preset with the following preferences: - MP4 files - Large file size - H.264 codec - Single pass encoding - Target size equal to the source files size - Picture settings: Anamorphic: none/loose and setting the size to the source files size. If I choose strict anamorphic, the file doesn't open with Quicktime. Also, if you are not familiar with the parameter setting, the other options you can take glimpse of Squared 5 or MacX Video converter pro, no complex setting.