HEVC or h.265 is the most advanced codec for now because it has the lowest bitrate without losing the image quality. The codec has three main features that distinguishes it from others: parallel decoding, random access to images within the video stream and larger maximum block size. HEVC is aimed to offer the same level of video quality as AVC (h.264), but with improved compression, that is why a video file compressed with the codec will be twice smaller.

This is a lossless-format (and encoding algorithm) for Apple platforms. M4A is widely used in iPod players and as a component in QuickTime media-players. The m4a codecs decoder is found in open sources – this allows third party users to open files in that format.