940717 - why "As Input" is disabled?

[hamidi]

hi
in 2.6.10, in x265 Configuration dialog, in Output1 tab, under Pixel Aspect Ratio, why As Input option is disabled? in 2.5.6, i always used this and now can't.
anxiously waiting for you replies
best

[Jan Gruuthuse]

As 2.5.6 never had x265 encoding that is why. 2.5.6 had only H.263.