This technology relates to an image processing apparatus, a method thereof, and a program making it possible to cut out an area in a desired direction of a panoramic image more easily and rapidly.When the image processing apparatus cuts out an area in a predetermined eye direction of a panoramic image projected on a spherical surface to display, this displays an area of the panoramic image projected on a virtual screen determined by a specified eye direction as an output image. That is, the image processing apparatus calculates a pixel position of the panoramic image projected on a position on the screen by an approximation function to generate the output image. At that time, the image processing apparatus evaluates an approximation error by the approximation function. Specifically, the image processing apparatus determines a range of a writing area such that the approximation error is not larger than an allowance when this obtains the pixel position of the panoramic image corresponding to each position in the writing area on the screen by using one approximation function. This technology may be applied to the image processing apparatus.