Matroska MKV container file MK3D is a 3D stereoscoping video format. It contains video and audio track data. He file uses binocular vision to achieve added image depth and space.

MK3D video stream data is divided into two parts: right and left, or upper and lower. It is worth pointing out that the format, just like all Matroska formats, is distributed under GNU L-GPL open-source license.