A sensor unit used in an ADV includes a sensor interface that can be coupled to cameras mounted on the ADV. The sensor unit further includes a host interface that can be coupled to a host system. The host system is configured to perceive a driving environment surrounding the ADV based on at least image data obtained from the cameras and to plan a path to autonomously drive the ADV. The sensor unit further includes one or more data acquisition modules corresponding to the cameras. Each data acquisition module includes a pixel alignment module and a frame processing module. The pixel alignment module is configured to reformat pixels of image data from an original format associated with the corresponding camera to a predetermined format. The frame processing module is configured to generate an image frame based on the image data and to transmit the image frame to the host system.