Although FCP can work and render float type data via a setting in the video setup dialogue box, it will only work as a functional editor with data well suited to video playback. I was shocked when FCP opened and played avi and mpg files, but I can not edit with them in an efficient manor. in out cards can work in 8, 10, and 12 bit resolutions, but the video needs to be in a codec that FCP will function with. On the io, apple and aja support the Apple UC 10bit codec. This is a true 1024 color per channel codec without alpha in a 4:2:2:0 YUV arrangement. The io also supports the black magic codecs in both 8 and 10 bit depths. The kona 2 cards can work with 12 bit video (4096 colors per channel) via there own 12bit codecs. All of this can be rendered and processed in a float setup with most filters and codecs, but FCP will only run well when the quicktime based codec meshes well with the hardware that supports it.
FCP nor QT supports natively “frame stack” data like what you describe. Instead, use a QT codec that supports 10-12bits and turn on float in the settings. Then any work that you do in FCP will be processed in a float environment, but in the codec transition you will loose the “cary over” or “greater than” information in the original file. Float based rendering will greatly slow down FCP’s operation. FCP 5 will have a full “shake 3” like implementation of float FPU based information.
Adam