Thanks to PS Vita’s OLED wide screen, we can play movies on PS Vita in a pretty good visual experience. However, something went wrong when you try to play some AVI or MKV videos on PS Vita, these two formats aren’t compatible well with PS Vita. From the official website of PS Vita, we can clearly learn that PS Vita only supports h.264 or MPEG-4 videos, and no mention of mkv or avi supported.
So if you plan to watch mkv or avi videos on PS Vita, you should do something in advance, to be honest, you have to convert avi or mkv videos to PS Vita supported video formats. H.264 mp4 format is a good choice. which is really a good balance between quality and video size. Meanwhile, i know a pretty good video converter to help you realizing it. Which is named Pavtube video converter.