An image acquisition device and a method for capturing image data is disclosed. The method comprises exposing an image sensor to light from a scene, selecting substantially all rows of sensor pixels in an image sensor in a substantially random order, starting an exposure period for each row of sensor pixels in the image sensor in the order the rows were selected, buffering the rows of sensor pixels comprised in an image frame until all rows of the image frame have registered image data for the presently captured image frame, and outputting image data representing the image frame by outputting image data from each row of sensor pixels.