An image pickup apparatus includes an image sensor array, a scaling circuit, an output circuit and a timing control circuit. The image sensor array reads N pixel lines according to a read timing control signal to capture N lines of pixel data of a source image. The scaling circuit receives the N lines of pixel data according to a scaling timing control signal, and refers to a scaling factor to scale up the source image to generate an upscaled image having M lines of pixel data. M is a positive integer greater than N. The output circuit outputs the M lines of pixel data according to an output timing. The timing control circuit determines a receiving timing according to the output timing and the scaling factor to generate the scaling timing control signal, and determines a read timing according to the receiving timing to generate the read timing control signal.