Does Blu Ray use MPEG4 codecs?

[frnd08]

have been having this doubt ever since blu ray hit india. some say it uses mpeg4, and many say its mpeg2 but uses a different codec than what is used in dvds. plz clarify.

 

[moserw]

have been having this doubt ever since blu ray hit india. some say it uses mpeg4, and many say its mpeg2 but uses a different codec than what is used in dvds. plz clarify.

For HD content using MPEG2 you can go to a maximum of 2 hours on a 25GB Blu-Ray disc and initially all HD-DVD and Blu-Ray content was on MPEG2. Now all the latest Blu-Ray titles are using MPEG4 to make room for more content like commentary, Blu-Ray Live, and other additional features. HD-DVD as you know is dead. Moving to MPEG4 has given room for twice as much content i.e. 4 hours of video or rather 2 hours of video plus other stuff which is what an average Hollywood movie runs for (i.e. 2 hours).

 

[frnd08]

For HD content using MPEG2 you can go to a maximum of 2 hours on a 25GB Blu-Ray disc and initially all HD-DVD and Blu-Ray content was on MPEG2. Now all the latest Blu-Ray titles are using MPEG4 to make room for more content like commentary, Blu-Ray Live, and other additional features. HD-DVD as you know is dead. Moving to MPEG4 has given room for twice as much content i.e. 4 hours of video or rather 2 hours of video plus other stuff which is what an average Hollywood movie runs for (i.e. 2 hours).

okay. so how much does the quality suffer coz of mpeg4?

 

[moserw]

okay. so how much does the quality suffer coz of mpeg4?

Actually MPEG4 is superior. A 1GB MPEG4 file will have same PQ as a 2GB MPEG2 file. Hence a 25GB Blu-Ray can hold 4 hours of video in MPEG4. Any MPEG4 format compressed file will have better PQ than an MPEG2 file as long as they are not compressed way too much like a 700MB file etc.

 

[marsilians]

have been having this doubt ever since blu ray hit india. some say it uses mpeg4, and many say its mpeg2 but uses a different codec than what is used in dvds. plz clarify.

Blu-ray is independent of the codecs - mpeg2 or mpeg4. The main differneces are the the point where the sources are being viewed (TV vs. computer) and the compression factors (or bit rates as its referred to ).

Video for TV is not as compressed as that meant for PC (web). mp4 maintains a relatively good quality even under high compression.

mp2 sources are much more prevalent and as such DVDs, VCDs support this predominantly.

For HD DVD, Sony chose mp2 while Toshiba chose mp4. We all know how that ended