Codecs

These BD-ROM compatibilities attorney specifications are for certain codecs hardware decoder (athletes) and movie - on (content). In video, all the players must support mpeg-2, h.264 / AVC, SMPTE mpeg-4 VC - 1 conversion is used, allowing the CDS regularly backwards compatibility. MPEG and VCEG. VC-1 is a decoding, mainly is developed by Microsoft. Blu-ray disc titles and video must be stored using three mandatory coding. In a single decoder several titles are allowed.

The choice of codecs affects the producer's licensing/royalty costs, as well as the title's maximum runtime, due to differences in compression efficiency. Discs encoded in MPEG-2 video typically limit content producers to around two hours of high-definition content on a single-layer (25GB) BD-ROM. The more advanced video codecs (VC-1 and MPEG-4 AVC) typically achieve a video runtime twice that of MPEG-2, with comparable quality.

MPEG-2 was used by many studios, including Paramount Pictures (which initially used the VC-1 codec for HD DVD releases) for the first series of Blu-ray discs that were launched throughout 2006. Modern releases are now often encoded in either MPEG-4 AVC or VC-1, allowing film studios to place all content on one disc, reducing costs and improving ease of use. Using these codecs will also free many GBs of space for storage of bonus content in HD (1080i/p) as opposed to the SD (480i/p) typically used for most titles. Some studios (such as Warner Bros.) have released bonus content on discs encoded in a different codec than the main feature title; for example the Blu-ray release of Superman Returns uses VC-1 for the feature film and MPEG-2 for bonus content (presumably because it is simply ported from the DVD release).

Audio, BD-ROM players must support Dolby digital, DTS, linear, etc. Players can selectively support Dolby digital with high resolution and DTS - HD, as well as the voice TrueHD and DTS - HD audio nondestructive format Dolby master. BD - ROM title must adopt compulsory primary background music. A medium audio track, if present, can use any of the mandatory or optional coding.

For users of digital TV programs, this record of Blu-ray disc standard for 36 Mbit initial data rate is more than sufficient and records any source HD broadcast (IPTV, cable/satellite, the earth). Video films have maximum BD - data transfer rate of 54 Mbit/s, most of the audio bitrate 48 Mbit/s (for Video and audio data), the highest rate of 40 Mbit Video bit/SEC. There, by contrast, the largest HD DVD movie data transfer rate of 36Mbit/s 30.24 Mbit maximum AV bitrate, the biggest video bitrate 29.4 Mbit/SEC.