Exporting to FLV with trasparent background

Question

Hello all,
I am finding myself in a bit of a delema...I have hundreds of little movie clips with trasparent backgrounds that need to be exported as FLV's.  From my experience (or lack there of) and knowledge, to find the best export settings to create a FLV that looks good with the lowest file size comes down to the good old trial and error method.  I've tried numerous different settings and to be quite honest, I can't really tell that big of a difference in the video when it's be exported at 200 kbps compared to 600 kbps.  Maybe I'm blind.  But, I do notice the size of the file(s) go up quite a bit.
The quesions are...
1. When exporting to FLV's with transparentcys, is it worth it to crop the frame size?  I've tried this a few different times and in fact noticed the file size go up after cropping the frame size.  One would think that the a file that is "smaller" in dimensions would be smaller in size.  Although, I guess it's more about the information being translated in the video.
2. Is there a trick to this exporting to FLV beast?
Thanks in advance!

Answer 1

I'm kind of wondering if it might be better to just include the backgrounds into the videos and export them as H.264
That would be an option. It really depends on what the page looks like that you'd be embedding these into. That's the nice thing about the transparency--you only really have to be concerned with the foreground. But, if your page is something simple, like a solid color, you'd probably get the same visual result by putting a color solid behind your keyed subject in Premiere, and exporting to a non-alpha clip, like an H.264 MP4.
do you know if you can dynamically load H.264 into a swf?
Umm... no I'm just a measly video guy
Seriously, though, you may want to have a look at F4V; that will probably do exactly what you need, as it's H.264 compressed video in an Adobe-ized container format. It's available in the FLV/F4V options you've been working with. Just note that, since it's H.264, it does not support an alpha channel.
Or, could I export to H.264, import the H.264 file back into Premiere and re-export as a flv?  I assume I'd still be stuck in the same position at the end of all of that though...
Worse You'll have applied a second round of compression rather needlessly. You can use some third-party trickery to rewrap an H.264 stream into an FLV--I've actually done this before for HTTP pseudo-streaming web videos--but you still won't have alpha.
I think this is just a matter of deciding how you want to fit the videos into the rest of the design. If it were me, and I had the flexibility, e.g. a solid background, I'd forgo FLV and use H.264 in an MP4 container or F4V instead.