I do not think you can use filters from the Filter Gallery which is stored in the Effects folder of PS.
Am I looking to do the impossible?
Sort of. The CS4 suite will allow you to open video clips in Photoshop and apply filters that way. In CS3, this is simply not possible.
Wow, this just seems like the most obvious function to include in the Suite.
I'm not a programmer, but I'd bet it's more than just a few lines of code to implement your request.
Well, neither am I (a programmer) but there's a long list of video effects that I can apply (including Mosiac, Posterize and Texturize) in Premiere, just not the specific filters that I'm looking for. It's like they've included a selected subset of filters from Photoshop and I just don't get why they're not all available.
Because there is a tremendous difference between PrPro and PS, this is not possible.
Now, some similar Filters (Effects in PrPro) exist, and there are some 3rd party providers, that write similar.
If you notice the files, you'll see that the Filters in PS are mostly .8BF files. In PrPro, they are .PRM's and mostly .AEX files, which stem from AfterEffects.
Sorry, though you can use Layer Comps and Import as Sequence to animate Paint Daubs, and many, many more, but this is at the image level, not the program level.
there's a long list of video effects that I can apply (including Mosiac, Posterize and Texturize) in Premiere, just not the specific filters that I'm looking for
While the base names sound similar, if you check the file extensions of each, in each program, you'll see a big difference. Now, you could try renaming a copy of a PS Filter from .8BF to .AEX and see what happens. I'd not expect PrPro to even open, so remember where it is, as I'll bet that you will be quickly deleting it.
To get close to what you want, you'll need to get PS Extended and do the work in PS, then Export/Import to PrPro.