Today, watching the live broadcast of Jobs's presentation in both realvideo G2 and quicktime 4 beta, We concludes that the poor quality of both is mainly due to the heavy network traffic.
We watched jobs in both QT4 and Real format from a 768 Mbps DSL. They are both set to 128 Kbps connection. We got about 48 Kbps QT4 stream and 80 Kbps RealVideo stream. The result was both suffered from the high network load (we use "get info" to observe the "percent loss" of the QT4 stream. QT4 suffered about 30% loss while RealVideo G2 had to rebuffer so much that it was not possible to follow the live event (QT4 still let us listen to the audio with lower quality video which is good for 30% loss).
Later on, we set QT4 to use 28.8K connection to get less BW (hopefully to reduce the percent loss). It worked better. Now we got about 10-15 percent loss and it gave us much better audio and video quality. RealVideo G2 now switch to 20 Kbps on its own but still it did not work!
In short, RealVideo G2 was a total failure. QT4 was quite good. It's great at surviving the overloaded network.
Bill and friends
P.S. Loss when network's jammed is normal. It's the result of either Random Early Discard (RED) or router buffer management or both. This guarantee quality of service to certain level. Network has to drop package to make sure the bandwidth/delay policy/priority is not violated.
We found the 100+ kbps QT4 stream of BBC ( http://www.apple.com/quicktime/showcase/news/bbc/bbc_world.m ov )is great! Even in double-size or full screen mode is good (240x180 in normal mode). Again, this is from 768 Kbps DSL.
[This message has been edited by MacNW (edited 05-11-99).]
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