HD-DVD 30 Go et Vc1 récent
BR 25 Go et Mpeg2 vieux
malgré la propagande de Sony
Don Eklund, executive vice president of advanced technologies de Sony Pictures Home Entertainment a écrit:However, Eklund says the company has discovered other advantages to using MPEG-2. "Since then, we've also done some testing with VC-1 and MPEG-4 AVC. We're finding they have some advantages when encoding at very low bit rates, but those low bit rates, as compared with MPEG-2, do not yield transparent picture quality to the original master. When you're encoding, you need to encode the noise that is part of the film grain of that master as well."
"What makes the films most difficult to encode, actually, is noise. And to make the best approximation of it, you need to use the highest available bit rate," Eklund says. "The bit rate we use for our typical releases is 18 mbps [megabits per second] average, with a 30-mbps maximum. And that is one of the key differences for HD DVD and Blu-ray: We have a higher bandwidth available for encoding than HD DVD has. It gives us a lot of flexibility even when we're working with the most difficult video masters."
As with DVDs today, and as other studios are doing with HD DVD releases, Sony will be using variable-bit-rate encoding on its discs, to optimize image quality. "The encoder can increase the bit rate selectively for difficult scenes," explains Eklund.
"Our goal from the outset is that we wanted the viewer to look at the video master on one side and the Blu-ray Disc on the other--and not be able to tell the difference."
http://www.pcworld.com/news/article/0,aid,126163,00.asp
Ben Feingold, president de Sony Pictures Home Entertainment a écrit:Content makers have a choice of three video compression systems to choose from on Blu-ray Disc, including MPEG2, which is used on current DVDs, and the newer VC1 and MPEG4 AVC formats.
Sony will employ the MPEG2 system because it can provide a better picture.
The new codecs are interesting but unproven.
http://www.blu-ray-disc-blog.com/?p=55
Et c'est bien les disques BR qui posent problème.
Test du disque Blu-Ray Hitch avec un lecteur Blu-Ray Sony Vaio (PC portable) et un projo Sony Rubis.
Les bruits vidéo sont tjs là.
http://www.avsforum.com/avs-vb/showthread.php?t=690190