The Flash Guru: Servers, Bitrates, and Audio Syncing

Got a Flash video question? Let Stefan Richter, the Flash guru, help you out. In this monthly series, Richter will answer Flash questions sent in by readers or from the Streaming Media forums.

Stefan Richter
Richter is the founding director of Muchosmedia, a UK-based software firm specializing in rich Internet applications. The company works for an international client base that includes ITV, Unilever, and the Tate Modern, and recently launched its first product, Scribblar, an online collaboration tool which is proving popular in the eLearning community. Richter also maintains his personal blog, the popular FlashComGuru.

Stefan tackles three short questions this week. The first comes from dave3D:

Hi, I'm kind of a newbie—ran a webcasting studio a few years back, encoding with Windows Media Encoder. I'm looking at Wowza Flash as a distribution method now. We will be streaming live, sometimes time-sensitive content, but I like the versatility of Flash and of course the fact that most viewers will have the player. Any experience out there with Flash encoding? I'm a Mac man and looking at Wirecast as an editing/encoding suite. Any info appreciated.

There isn't a specific question here, but Stefan was happy to offer some advice on the topics you brought up. Wowza is basically an alternative to Flash Media Server, he says, one not made by Adobe. It can be used to stream Flash video live and is cheaper than Flash Media Server.

Depending on the size of your audience, however, you might be better served going with a content delivery network (CDN). Go with your own server is you have a small- or medium-sized audience, Stefan says, meaning under 1,000 viewers. If your audience is larger than that or is spread out around the globe, go with a CDN. A CDN offers data redundancy, which you won't get running your own single server. These numbers aren't absolute, Stefan points out, and if you're in doubt go with a professional service.

As for an encoder, he recommends Flash Media Encoder from Adobe. It only runs on Windows, but you can run Windows on a Mac using Parallels or another PC emulator, so that's an option.

If you have more specific questions as you get going, write in again.

Our second question comes from Matt:

With all online Web media, especially video when streaming, it never seems to use much of my connection at all (fluctuating between 50 – 60Kbps) and that makes it pause continuously. This happens on many Web sites including MegaVideo,, etc. I have a 1MB connection so it shouldn't be a problem streaming.

Could someone help me configure my web browser or is there a player I can use which will use the link of the stream and play it through that?

If you've got a 1MB connection, this shouldn't happen, says Stefan, but the answer isn't configuring your browser. Perhaps you're only trying to stream video at peak times and not getting the full connection speed.

To test your line speed, use an online service like . If your speed isn't close to what your Internet service provider promised you, call them and ask them to troubleshoot the line.

Craig writes in with our third question:

We are having intermittent issues with lip-syncing to video after trimming FLV files (either under H.264 or VP6). Since Adobe don't seem to have an official tool for doing this we are using third-party software such as FLV Knife and Avidemux.

I am guessing this is some sort of keyframing issue but I'm not sure.

Anyone had similar issues? Can you recommend a more solid solution?

"That's a tricky one," Stefan says, since you can't simply trim an FLV file. It's not a format for post-production work. He's not sure if you'd be better off with an H.264 format file. QuickTime Pro can trim FLV files, though, though you may have to re-export the trimmed file as a MOV file and re-encode. "I can't really offer him any quick fixes for that," he says. If you have the source material in a different format, you'd be better of editing that and then re-encoding.

When it's pointed out that the question comes from Craig Moehl of, whom Stefan knows personally, he adds, "Craig, give me a call if you want to discuss this further" and says he'll ask around for other FLV editing tools.

Submit your Flash video questions to Streaming Media’s Formats, Codecs, and Players forum, or send them directly to the author at<>

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