How to do streaming video?

[Jon_King]

I have a large mpg file my client wants his customers to view in a stream as opposed to simply downloading and opening locally. Is it difficult? How or where do I find info on this?

[jpjones]

Unless both your clients' server and all of his customers have a big fat pipe to the Internet - forget about streaming the MPEG file directly - the experience for the user would be dismal. The video would be very jerky to say the least! (This is assuming the MPEG file is very very large). Of course, if quality is also of the upmost importance - the best bet is to download and view locally.

Otherwise, the best way is to encode it into a format suitable for streaming over the Internet. Which format? Well, there's really three choices:
Real
Windows Media
Quicktime

Once they are in one of the above formats - they can be streamed either via a media server (which is the better choice if you have clients connecting on both dial-up and broadband, as the MPEG can be encoded to cater for both, with the server providing the appropriate quality according to the available bandwidth), or using HTTP from a standard web server (where you can only use a single bandwidth rate).

The encoders for the above formats can be found on the appropriate sites of Real [realnetworks.com],Windows Media [microsoft.com] and Quicktime [apple.com].

HTH,
JP

[Jon_King]

Ok.. I'm starting to get it.

About the media server... how is this different than my standard server? Is this something I can serve up or do I use an outside media streaming server?

[jpjones]

A media server is different to a standard server in that:
a) It generally runs on a different port to port 80 (the HTTP port)
b) It can negotiate delivery of content according to the available bandwidth
c) It can broadcast live feeds from one PC to many clients.

A media server generally can run on the same server as a web server, as it uses different ports. Note - it can be a memory hog! You'll more than likely need root/administrator access to install it. Windows Media Server only runs on a Win2K (maybe NT4 too) platform, though the new Real Helix Server will stream WM content too, which is nice. Having just installed Helix last week on one of my boxes, it seems to do a good job of it too!

Re: b) - This is probably the major difference. Whereas a normal web server will simply (unintelligently) serve whatever it is told to fetch by the requesting client, a media server will talk to the client and deliver the content at a speed the client can reliably receive it. If the user is on a modem, the media server can serve out the content so that neither the audio or video breaks up, but instead the quality of both picture & sound will be decreased when compared with a faster link such as broadband. Also, whilst a client is viewing the content - if the available bandwidth decreases, the server can switch the content delivery to a lower quality so the clients' viewing is unaffected by pauses.

If you were to stream the file from a normal web server - the bonuses are no need to install a server and go through the installation procedure and worry about lessened security, but you'd have to build into your web interface an option to choose the connection quality before viewing, so the appropriate content can be delivered. Also, the client is more likely to experience pauses.

It all depends on the application and the viewing audience as to which route you choose.

Hope I'm not waffling too much!
JP

[hakre]

just to drop in: mpg is a stream (that's why the files are often called mpeg streams) and your webserver will stream it out for you. ;)

one example of mpeg streams in real life is the digital sattelite tv.

[Jon_King]

This is neat and easy.... yes I have encoded to different bandwidths, provided a choice via descriptive links and viola... instant video.

Thank you very much.
Jon