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Re: Intelligent Streaming and SureStream

Sorry. I thought you were confusing MS's and Real's approaches to bandwidth usage with QT's. I think Ben's book on compression talks about these technologies.
He does cover it but out of 447 pages it's just half a page for SureStream and one sentence for Intelligent Streaming :-(
I have to add that I'm talking about the part in which he describes the technologies in general. I'm sure that there is a wealth of information on how to use it and also information on the two technologies spread throughout the book. Don't get me wrong here, I think it's a great book for compressionists. The problem is that I need information like "does Intelligent Streaming use a sender-based or reciever-driven approach for bitrate adaption" or "How do they seamlessly switch between the streams" etc.
I do have a some information on SureStream but nearly nothing at all on Intelligent Streaming. The only usefull information I got on Intelligent Streaming came from Ben via this list.

The reason I mentioned these is because they're used to deal with different bandwidth situations.
Ah, now I get it. But aren't those two basically about buffering (which isn't really something special or unique)?

As for stream switching QTSS does "thinning" of the stream, which is not switching much though.
Any idea how that "thinning" is done? This would mean that there is at least some kind of congestion detection and rate control implemented in DSS/QSS. I always thought that QT Player simply buffers a couple of seconds to reduce dropouts due to bandwidth fluctuation. I also don't understand how B-Frame dropping with Sorenson Video 3 is implemented.

My understanding is that the main difference between "Intelligent Streaming" and "SureStream" is that SureStream encodes all video versions at the same window size while Intelligent Stream actually contains more than one resolution.
From the compressionist point of view it certainly is but I'm pretty sure that it's implemented differently and there is my problem. According to "Video Coding for Streaming Media Delivery on the Internet" by Conklin et al. SureStream uses a reciever-driven approach which means that the client monitors the actual bandwidth and loss characteristics of its connection and instructs the server to switch to another stream if needed. I guess that Intelligent Streaming works the same way but I don't know it for sure. After all it's also possible that the server monitors the network characteristics.

My understanding is that the MPEG-4 spec does allow for stream switching in a very powerful way (kind of a mix between thinning and intelligent stream) but AFAIK QTSS/QT has no support yet.
MPEG-4 features layered scalability which is a different aproach to the one currently used by Real and Microsoft. Instead of multiple versions MPEG-4 uses multiple layers. Especially the Fine-Granular Scalability (FGS) originally proposed by Radha et al. features a powerfull way to adapt to bandwidth variations and fluctuations. Just google for "The MPEG-4 Fine-Grained Scalable Video Coding Method for Multimedia Streaming Over IP". Interestingly there is a lot of work done on layered video coding by Microsoft Research Asia :-)

Gru_
Marc
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References: 
 >Re: Intelligent Streaming and SureStream (From: Francesco Schiavon <email@hidden>)



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