Yes, it can -- but I don't recommend mixing the two formats in the same project.
You're best to open a DV project, place your standard def AVIs on the timeline and Share/Personal Computer/MPEG as 1440x1080. This will create a hi-def HDV file.
You don't say what your source is for hi-def video, so I can't make specific recommendations in this regard. But if you convert it also to HDV (if it isn't already) you can then mix the two videos together and output a BluRay.
I'm just curious though -- if you've got no hi-def gear, no hi-def camcorder and no BluRay player -- where your hi-def video is coming from and how you're planning to play this video when it's done. It's hard to give you anything but general advice otherwise.
well I think material is going to be from blu ray discs, hd camcorders and small hdv decks. I know may way around a video TS folder now, and thanks to streamclip its easy to ready a vob clip for use in a DV project, but I have no idea about the file structure of a blu ray disc - yet. Are there a dozen different HD codecs already or can we convert them into a Prem El friendly clip?
PRE likes HDV, so take a look at this entry in FAQ, it should help you out: How can I convert my AVCHD footage to more traditional HDV?
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