Tim,
Let me try to help here. Avid Meridiens do not take in video via FW. Only through the BOB or as an imported file. All imported files have to be converted into OMF. A QuickTime file using an Avid codec still has to be rewrapped as OMF, hence the import process. If everything is done correctly in the conversion to the Avid-formatted file, then the software engages a Fast Import mode, which is essentially a file copy/wrapping step. If something is slightly wrong, it takes longer. Generally about the same, as if you had used the animation codec or something similar.
The JFIF 2:1 codec means that the resulting video is encoded as 720×486, 8-bit, 4:2:2, D1 aspect ratio, value-rate Motion JPEG at 2:1 compression (max) at 29.97 (in NTSC). Your file size should be around an average of 2 min./GB with this codec, but since it is a variable-rate codec, this isn’t an exact amount (plus audio, of course).
The 2GB file limit has to do with dealing with legacy OS types and versions, since you might create a file that is intended to run on an older machine and, therefore would have a problem. It’s an Avid thing, but mainly to protect older systems.
Unfortunately, you’d probably get the best results by simply going component analog SD out to a DBeta deck (or similar) and then ingest via SDI into the Avid. That would be real-time (twice). Remember also that in Avid land, you can mix any of the 2-field compressed codecs, any of the 1-field compressed codecs, but you cannot mix compressed and uncompressed media, nor 2-field and single-field media. Hope this helps.
Sincerely,
Oliver
Oliver Peters
Post-Production & Interactive Media
Orlando, FL
http://www.oliverpeters.com