[Request] De-interlacing Option with Interpolation (using adjacent lines only)

[WhenJavaAttacks]

Hello. I'm not 100% sure if my request is possible, although it seems like it wouldn't require anything the OSSC isn't already capable of, but please correct me if wrong.

Basically, I'm wondering if it would be possible to implement a de-interlacing similar to bob, but instead of repeating lines it would use an average of the adjacent source lines to fill in the additional lines (I believe this is similar to linear scaling). This should only require the current line and previous line from the current source field, which (if I understand correctly) the OSSC currently buffers anyway, and I believe the math is simple enough to not be of any issue either.

To be clear, this method won't outright solve the issues of flicker and such that bob de-interlacing tends to have, but it should serve to soften them (the interpolated lines should differ less from the actual lines that follow in the next field). I believe it would be a nice option to have in addition to the normal, line-duplicated bob and should be a tangible improvement in many cases.