Some of what I see there seems like distant keyframing issues but I'm presuming you're saying you're using a gradient mask and it's not working? I see your notes appearing and a very rapid wipe effect revealing them. They don't appear to blink on so I think you were just expecting a gradient-esque mask?

Personally I would have done this in After Effects rather than Flash in the first place but that aside

If you are using mask gradients are you using the actionscript method of applying the mask so the gradient works? Exported movies (Flash File->Export Movie) doesn't utilize actionscript so that would explain that. However it not working in After Effects is probably a byproduct of the same thing. After Effects probably cannot parse ActionScript to make a proper gradient mask work.

Ok if you don't know about gradient masks lets just ignore that. Your video looks just like the SWF only there's video artifacts. Are they what you're referring to? The trail of video being left behind and not updated? That's just standard video artifacting that's only being cleaned up every keyframe.

What exaclty are you experiencing in After Effects? Are you importing the SWF into After Effects or are you exporting a movie from Flash and are importing that?

I can verify the mask doesn't import into After Effects. I tried masking text, a shape and a bitmap. I applied the mask with and without actionscript. The text was never revealed but it knew the correct amount of frames in the SWF.

I would recommend exporting a video from flash and reimporting the video into After Effects.

Set your video to export to Quicktime Animation at Best quality. Import that into AE and it should be perfect. It is a lossless codec, although the filesize will be large.

Example:

If there is no transparency you can try changing the Depth to Millions of Colors (without the +, which is alpha). Otherwise you might want to right-click on the video in AE and select Interperet Footage->Main (or hit CMD+ALT+G) and set the Alpha setting at the top to Ignore.

Perhaps my more advanced encoders can help you. They're not Adobe but if you send me the FLA I can export it and try using them to give you something back you can use. Just shoot me a link to a FLA to export for you in here or private message.

Here's the Quicktime Animation output with transparency (although remember, extremely thin lines don't do so well in low resolution:

Animation Millions+ Encoding

And here's an example showing the transparency works, not artifacting in either (using a forum screenshot underneith):

Overlay Example

I did forget to mention on that first dialog to check of to ignore the background color (produce an alpha channel). You can see it in your example images.

Nothing special actually. I'm not even at work at the moment, I did it at home using just Flash and AE. I exported using the very same settings depicted in the photos above, besides checking off to allow alpha.

I'm very familiar with that artifacting. A site like vimeo, youtube, etc will always use a very far apart keyframe to reduce the filesize, so I assumed originally vimeo was the culprit and not Flash.

This is just a file->export->movie to Quicktime Animation, Millions+ colors with Alpha checked off at best quality. Exactly like the pic.

Perhaps you have something else installed that is interfereing with your video overlay like ffdshow can intercept video? Check you add/remove programs for ffdshow. Libs like that which are safe and very common can sometimes intercept video overlays.

Glad you got what you needed and you're welcome.

I meant when you upload your video to a video service such as youtube/etc it can recompress your video and create those artifacts. You're saying Flash itself is exporting those artifacts though. Very odd considering Quicktime is an Apple product and I'm exporting it without issues on Windows .

It just may be Flash. You can always try another codec. I'd be irritated if the most universal lossless Apple Quicktime Animation didn't export correctly on a Mac . It'd be less weird if the issue persisted across multiple formats (mpeg4/h264/animation/etc). Then it's just a Flash issue to me.

Anyhow you're welcome and good luck!