Advice for best FLV performance

M

mlacher

New member
I'm delivering 30sec-2min FLV clips within flash animations for a client. The clips are of talking actors: 15fps, 256kbps, On2 VP6, with alpha channel (they're composited atop interactive backgrounds in Flash). They're preloaded before the user sees them, and they play through NetStream objects. Neither I nor anyone else working on this project has seen any problems in performance, but the client keeps complaining that the video is jerky sometimes.

I'm fairly certain it's just due to watching it on slower computers, but they're adamant about fixing it. I've tried numerous things which have led to the current settings, the best so far. I've tried ditching the alpha channel and comping in the background in the video, but it didn't help (it seemed worse to them. sigh...).

Does anybody have more ideas about how to make the FLVs perform better? I'd appreciate any ideas.

Thanks,

Mike
 
the client is complaining about 15fps at 256kbps?? good grief... i'd be asking what cpu their computer has.

what frame size are you using? what encoder? are they doing the playback on their local computer?

vp6 has newish profile that affects the decoding complexity of the flv... but at that bitrate, it shouldn't be an isse.
 
Thanks for the reply. I'm continually unable to tease out specs, but I'm pretty positive their computer is slow or deeply troubled. I know I've seen them working on microscopic netbooks. They're of the belief it should run flawlessly on every computer, which is of course a pipe dream.

The frame size varies somewhat, but one of the most troublesome videos is 776x504. I used After Effects to encode all the videos. Users access the Flash app over the internet, but all of the flash content and videos are preloaded, so it should be running off their hard drive.

Would changing the videos to H.264 make any difference (i'd have to lose the alpha channel and comp in backgrounds)? My understanding is that's actually more CPU intensive, but I'm looking for any shot in the dark at this point.

Thanks!

Mike
 
Using H.264 will use more CPU and does not support alpha channel.

Tell your client that they will either have to reduce frame sizes, or live with the fact that people with slower, broken computers will have playback issues. Its a technical issue that you cannot control, and not every PC will be able to play back the content (for example, people on Legacy Mac OS 9 or less will not be able to play back the flash content, since its not updated for Mac OS 9)

Try getting your clients to install Flash 10 on their computers. Flash 10 has some speed improvements for all flash content.
 
the flash encoding profile that i was referring to is known as vp6-e... if you encode using the vp6-s profile, the picture quality won't be quite as good, but it will play back easier... those are options that are available on pro encoding software packages like squeeze 5, i don't know if you can do that with after affects.

streaming media magazine did a comparison test on the overhead required to playback vp6 vs. h.264 vs. silverlight, and surprisingly, according to them, h.264 didn't require more cpu, at internet bitrates... fwiw, since h.264 has better picture quality, you can lower the bitrate, vs. vp6.

what encoder does ae use? if it's the quicktime encoder, the quality will suck, you won't be able to select vp6 profiles, etc... if there is no other way to placate this weird client, you might have to get the job professionally encoded, or tell them to put the content online at a couple of different bitrates.
 
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