DaViD Boulet
Senior HTF Member
- Joined
- Feb 24, 1999
- Messages
- 8,826
Amir at AVS has already confirmed that bandwidth limitations of HD DVD would not permit more than one lossless audio track for most films if optimal picture quality was to be preserved.
Here's how bandwidth matters. And this is true for all disc formats like DVD, HD DVD, and BD:
All content that can be accessed on-the-fly, like multiple angles, subtitles, and soundtracks, is recorded to be read off the disc as a *single stream* and therefore shares (must fit into) the same "read rate" or bandwidth of the disc. Think of a Disney DVD with 3 languages... even though your listening to just one language, the other two 5.1 Dolby signals for French and English are being read off the disc at the same time and are simply not being sent out your digital output. But they're there taking up precious bandwidth space all the same. That's why sometimes DTS has to be scrapped to preserve picture quality etc.... there just isn't enough room along side a 5.1 English mix, 2 other languages, and 2 commentary tracks given the bit space that the video needs. Not enough bandwidth.
Because all video and audio tracks that need "toggle" ability need to be streamed simultaneously they all share the same bandwidth. Were Peter Jackson to decide to give us LOTR on some sort of HD disc in 1080p with lossless 24/96 or 24/48 audio, HD DVD wouldn't have enough bit-space in available bandwidth left over for an additional lossless music-only track of the score (confirmed by Amir at AVS).
Jackson wanted to provide music-only tracks on his last extended cut DVD releases but had to remove them from the featureset because it used too much bitspace and compromised picture quality. With BD, those kinds of "rob Peter to pay Paul" bit-allocation concessions would be much less of a problem. With HD DVD, we have the same tug-of-war for bandwidth as we do on DVD, only in High-defintion.
Here's how bandwidth matters. And this is true for all disc formats like DVD, HD DVD, and BD:
All content that can be accessed on-the-fly, like multiple angles, subtitles, and soundtracks, is recorded to be read off the disc as a *single stream* and therefore shares (must fit into) the same "read rate" or bandwidth of the disc. Think of a Disney DVD with 3 languages... even though your listening to just one language, the other two 5.1 Dolby signals for French and English are being read off the disc at the same time and are simply not being sent out your digital output. But they're there taking up precious bandwidth space all the same. That's why sometimes DTS has to be scrapped to preserve picture quality etc.... there just isn't enough room along side a 5.1 English mix, 2 other languages, and 2 commentary tracks given the bit space that the video needs. Not enough bandwidth.
Because all video and audio tracks that need "toggle" ability need to be streamed simultaneously they all share the same bandwidth. Were Peter Jackson to decide to give us LOTR on some sort of HD disc in 1080p with lossless 24/96 or 24/48 audio, HD DVD wouldn't have enough bit-space in available bandwidth left over for an additional lossless music-only track of the score (confirmed by Amir at AVS).
Jackson wanted to provide music-only tracks on his last extended cut DVD releases but had to remove them from the featureset because it used too much bitspace and compromised picture quality. With BD, those kinds of "rob Peter to pay Paul" bit-allocation concessions would be much less of a problem. With HD DVD, we have the same tug-of-war for bandwidth as we do on DVD, only in High-defintion.