的 Flash Guru: Servers, Bitrates, and Audio Syncing

有一个Flash视频问题? Let 斯特凡•里希特, the Flash guru, help you out. In this monthly series, Richter will answer Flash questions sent in by StreamingMedia.Com阅读器或来自 流媒体论坛.

Richter is the founding director of Muchosmedia, a UK-based software firm specializing in rich Inter网 applications. 的 company works for an international client base that includes ITV, 联合利华, 泰特现代美术馆, and recently launched its 第一个 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. 的 第一个 来自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. 我们将进行直播, 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. 欢迎提供任何信息.

的re 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, 然而, you might be better served going with a content delivery 网work (CDN). Go with your own server is you have a small- or medium-sized audience, 斯蒂芬说, 意思是小于1,000观众. 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. 这些数字不是绝对的, 斯特凡指出, and if you're in doubt go with a professional service.

As for an encoder, he recommends Flash Media Encoder from Adobe. 它只在Windows上运行, but you can run Windows on a Mac using Parallels or another PC emulator, 这是一种选择.

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

我们的 第二个问题 出自马特:

与所有在线网络媒体, 尤其是流媒体视频, 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, Justin.电视等. 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?

如果你有1MB的连接, 这不应该发生, 斯蒂芬说, 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 Speedtest.网 . If your speed isn't close to what your Inter网 service provider promised you, call them and ask them to troubleshoot the line.

克雷格写信给我们 第三个问题:

We are having intermittent issues with lip-syncing to video after trimming FLV files (either under H.264或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.

有人有类似问题吗?? Can you recommend a more solid solution?

"That's a tricky one," 斯蒂芬说, 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格式文件. QuickTime Pro can trim FLV files, 虽然, 虽然 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 GroovyGecko.com, 斯特凡认识的人, 他补充说, “克雷格, 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 流媒体’s Formats, Codecs, and Players forum, or send them directly to the author at tdreier@zjkept.com<>