5Dii - semi 4:3 for 2X anamorphic lenses

Issue #758 wontfix
Eenimon
created an issue

Is there a way to take a part of the horizontal lines (4:3 window) but interpolate them down to 1920px (16:9)? In that way we could use cheap 2X anamorphic lenses, but still have a more high res source to unsqueeze, instead of horizontally cropping / wasting the 16:9 video in the post to achieve 1:2.66. As far as I know the GH1 hack can already do 4:3 video. The 16:9 output of a 4:3 window would actually have a half-unsqueezed aspect ratio and would be useless without completely unsqueezing in the post, but the resolution gain would be very helpful. Also there would be no need for altering / dealing with the 16:9 compression codec. Is the horizontal interpolation function of 5D already reverse engineered, or is it still part of the unknown territory?