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Streaming DVD Video over the Internet
Sexy Commando writes "According to this article on ZDNet, the new codec, H.264, is able to stream DVD quality video using bandwidth as little as less than 1Mbps. The new codec requires 3 to 4 times as much CPU power than MPEG-2 to process the video. Now we can have two movies on 1 CD. Cheers."
Here is the VideoLocus press release for H.264/MPEG-4 AVC.
I once shot a man who posted too many, "Imagine a beowulf cluster of these"
No. Dolby AC3 would take 384 kbit/s, for all channels.
H.264 exists as MPEG-4 part 10, basically using the AVC rather than the ASP profile for encoding.
Supposedly, it offers up to 2-4x size reduction over the MPEG-4 ASP.
However...
For anyone who has extensively played with the existing ASP codecs available (basically XVID, DIVX, RV9, and WM-whatever), the quality matters a *lot* based on the implementation. And not in any consistent way, letting you pick "codec X does the best job". Nope, more like "on low-motion sequences, codec X does best. For detail, codec Y. For minimal artifacts but some bluring, codec Z", and so on.
I see no reason to expect H.264 will follow any substantially different path. In another 5 years, it might well let us get a DVD quality movie onto 1 CD. For now, don't hold your breath about this changing the scene overnight. By the time this really does make good on its potential, we'll have the bandwidth and storage to make it unnecessary.
Deep Fritz wins game 5!!
remember how fast CSS was cracked
Yeah, I remember. DeCSS came out end-1999, years after DVDs were released until. And it was only possible because a DVD player manufacturer screwed up in their design and allowed their private key to be sniffed out, allowing them to generate all the other "secret" keys.
AC3 streams use lossy compression. They can use as much as 640kbps, but typical DVDs use either 384 or 448 kbps.
Sorry, here's your reference.
Uh...probably because they're generally talking about DVD players/set-top boxes? You know, devices that don't have x86 or PowerPC processors, and are generally spec'd to have a processor that is barely adequate for the job (for power, heat, and cost issues, they usually only want a tiny headroom, hence why the current crop of set-top boxes would largely be insufficient for this new codec).
The economist has a great article reviewing the latest codec offerings from different players. Specifically DivX 5.0 "is said to be particularly good at preventing tearing, a playback error that occurs when the software cannot render the video for display at the same pace that it is being decompressed and fed into the media player. And a new codec from supersecretive Pulsent claims to be object rather than block based. Whereas block-based compression and object-oriented codecs slice up backgrounds and foregrounds into grids, the Pulsent approach actually pinpoints real-world items in the frame--such as a person, tree or building--and processes each element separately. story here
1-Players capable of playing multiple soundtracks, for multiple languages and/or commentary.
That has nothing to do with divx. There are other audio codecs out there that support multiple soundtracks. I have a film that has the normal soundtrack and you can take the codec configuration and swap it to the "making of" soundtrack. Another film has two languages. This isn't popular yet, but you can definitely do it.
Except that the movie only has to be encoded ONCE and shared. As long as the decoding is easy enough for an average computer it will be widely adopted.
It's just that the lower bitrate will still get you good quality encoding, where before your quality went to hell as your bitrate went below 700 kbps.
Codecs like these ARE in fact lossy -- but that's not a bad thing, really. Most of the time you don't lose anything you notice, or really care about. Ok, let's think about this in a different way: You have a 747 and a cessna single engine plane. Each can carry a payload, but the 747 can carry much more. Both the 747 and the cessna are travelling at an imaginary speed, say, 700kbps. The 747 travelling at 700kbps will carry more than the cessna travelling at 700kbps. Now, to apply this to this story, instead of the cessna it's DiVX and instead of the 747 it's H.264. You can't "PKZip" a dvd and expect it to get much smaller, mainly because most lossless compression algorithms don't compress binary data too tightly.
An open source implementation is already in the works.