AVC/H.264 profiles designed for distribution process video as 4:2:0 8-bit. Since the SDI links transport 4:2:2 10-bit signals, video components need to be downscaled and sub-sampled prior to encoding and up-scaled and up-sampled after decoding.
This 40% reduction in information was originally intended to simplify encoder and decoder designs, which is highly desirable in consumer application. Whether it pertains to production or contribution applications, video quality has to be kept to the highest possible level in order to handle several encoding decoding steps. A mismatch in the chroma sampling and video component bit-depth can introduce degradations that worsen with each generation.
For this reason, the ability to process natively 4:2:2 10-bit signals was added to the AVC/H.264 standard in the High422 profile. ATEME has managed to develop its codec thru open standard and bring it to the real time processing world enabling native video compression for transport or archiving purposes at never seen before bandwidth use.