animation - iOS uiscrollview rotate images as the user scrolls -

i have horizontal scrollview image need rotate user scrolls left or right. needs rotate user moves scroll across screen. if user scrolls half way , stops image should rotate halfway etc. have looked @ few examples nothing seems giving me correct result. can 1 please help.

thanks in advance

you'll need implement scrollviewdidscroll method , apply rotation matrix image. rotate uiimage can outline here. how rotate uiimage 90 degrees?

however, better accomplished in pan gesture recognizer. pan gesture give information how far user panned, , can rotate image based on distance.