of HEVC. Tiers and levels The HEVC standard defines two tiers, Main and High, and thirteen levels. A level is a set of constraints for a bitstream. For levels below level 4 only the Main tier is allowed. The Main tier is a lower tier than the High tier. The tiers were made to deal with applications that differ in terms of their maximum bit rate. The Main tier was designed for most applications while the High tier was designed for very demanding applications. A decoder that conforms to a given tier/level is required to be capable of decoding all bitstreams that are encoded for that tier/level and for all lower tiers/levels. The maximum bit rate of the profile is based on the combination of bit depth, chroma sampling, and the type of profile. For bit depth the maximum bit rate increases by 1.5× for 12-bit profiles and 2× for 16-bit profiles. For chroma sampling the maximum bit rate increases by 1.5× for 4:2:2 profiles and 2× for 4:4:4 profiles. For the Intra profiles the maximum bit rate increases by 2×. The maximum frame rate supported by HEVC is 300 fps. The MaxDpbSize is the maximum number of pictures in the decoded picture buffer. Decoded picture buffer Previously decoded pictures are stored in a decoded picture buffer (DPB), and are used by HEVC encoders to form predictions for subsequent pictures. The maximum number of pictures that can be stored in the DPB, called the DPB capacity, is 6 (including the current picture) for all HEVC levels when operating at the maximum picture size supported by the level. The DPB capacity (in units of pictures) increases from 6 to 8, 12, or 16 as the picture size decreases from the maximum picture size supported by the level. The encoder selects which specific pictures are retained in the DPB on a picture-by-picture basis, so the encoder has the flexibility to determine for itself the best way to use the DPB capacity when encoding the video content. Containers MPEG has published an amendment which added HEVC support to the MPEG transport stream used by ATSC, DVB, and Blu-ray Disc; MPEG decided not to update the MPEG program stream used by DVD-Video. MPEG has also added HEVC support to the ISO base media file format. HEVC is also supported by the MPEG media transport standard. Support for HEVC was added to Matroska starting with