1. An image capturing apparatus comprising: a storing module, storing a look-up table; an image capturing module, capturing an image, the image comprising a plurality of pixels; and a processing module, performing a rotation calibration and a tilt calibration for the plurality of pixels to output a calibrated image after searching the look-up table; wherein, the tilt calibration comprises a focusing calibration and a trapezoid calibration, and the processing module performs the focusing calibration for the pixels by a sharpness manner, and performs the trapezoid calibration for the pixels by pixel mapping, interpolation or extrapolation.