Ask questions to BD authoring and compression insider "2themax"

[2themax]

Originally Posted by patrick99

A question that has been the subject of some controversy here lately is the question of at what point the length of a movie begins to raise a possible need to use more than one BD50 disc. Paidgeek has said that LoA will fit on one disc with no compromise in PQ or AQ. There was a recent heated discussion here about whether the LOTR EE's would benefit in terms of PQ and AQ from being spread over two discs each. It would seem this issue would be presented in every case with any TV series.

Are there any insights you can offer us from your perspective on this subject?

Many thanks once again for your participation here.

How about I offer some numbers. We'll assume a few things first. Each title would be on BD50, there would be 3 Dolby Digital 5.1 @ 640kbps tracks, 1 Dolby TrueHD 5.1 track, and no extras on the disc with the feature. Also, LOA would be a 16bit audio track and LOTR would be at 24bit.

LOA:
- ABR: 24-25Mbps
- PBR: 40Mbps

LOTR EE (ROTK):
- ABR: 18-19Mbps
- PBR: 39Mbps

If you drop each to a single lossless track, it'll jump about 2Mbps on the ABR and the PBR on LOTR would jump to 40Mbps.

Granted, this is all speculation. Each studio may have completely different thoughts on what the disc should contain. For instance, New Line would more than likely do DTS-MA on LOTR. My opinion, LOA is fine as it is and LOTR should be split across 2 BD50s. With that split though, I'd add PIP and 7.1 lossless to the feature.