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Hi10P (also called "10-bit") is a profile of the h.264 video codec. It has recently become popular in the anime scene for video encodes. The previous release of XBMC (v11 "Eden") did not support the h.264 Hi10P profile, but the current v12 "Frodo" version does.
The first stable version with Hi10P support is XBMC v12 (Frodo).
1 Hardware requirements
Hi10P won't work on ARM or even Intel ATOM processors (maybe one day, but none of the current ones in 2013 can do it). Hi10P can't be hardware decoded (which is to say, no one makes hardware decoders for them and no company plans to add Hi10P hardware decoding in the foreseeable future), which is what Raspberry-Pi, Android, ATOM processors, and some AMD APU systems require for smooth playback of demanding video (Hi10P is very demanding). Thus, Hi10P requires CPU/software decoding.
A safe bet would be at least a Core 2 Duo/Celeron G530 processor (or equivalent AMD) or higher.