Atlas TVI has two modes.
Both "A" and "B" are not related with resolution.
Since there is no standard aliment protocol for TVI , each manufacturer just copy each other .
"A" is most common aliment and "B" is kind of rare now.
Because of that we made two different aliment setting in the DVR and named them "A" and "B".
Both "A" and "B" work with 720 & 1080.