Offering Multiple Bitrates

[kieranmullen]

I am new to streaming but it seems a bit silly if one wishes to offer multiple bit rates to have to stream those individual streams from the point of origin. Would it not make more sense to stream HD to the server and have the server transcode to lower bitrates (yes with compression loss of course) We are only on a T1 which is normally a good solid connection but it is preventing us from offering multiple bit rates. Thanks!

[bwalls]

That is the direction things are going. That was one of the major trends I noticed at this year's National Association of Broadcasters' Expo. Wowza now offers transcoding on the server, Haivision premiered an "in the cloud" transcoding and publishing solution, Livestream was showing a service as well. Lots of opportunity to transcode in the cloud are popping up as an additional service from CDNs.

The thing is that transcoding costs a lot in CPU/GPU horsepower. Since you're already investing in what's hopefully an excellent encoder on the source end, it doesn't cost a lot more to be able to do several smaller streams. A Wowza server could serve dozens of adaptive live streams to hundreds or thousands of users, but could likely only do the transcoding for one. There's lots of horsepower "in the cloud" at reasonable prices, but you start having to deal with issues of latency and synchronization. So, it's all a trade off. In your case, where bandwidth is a hard limitation, you probably are better off going with one high quality stream and paying for transcoding on the other end, rather than do a set of lower quality adaptive streams. For users with ample bandwidth, it may still make sense to do all the encodes at the source.