A hologram reproduction apparatus includes a light-receiving unit such as
a two-dimensional sensor which obtains two-dimensionally modulated image
data, and an A/D converter which A/D-converts analog data obtained by the
light-receiving unit into digital data. In addition, the hologram
reproduction apparatus detects a number of pixels having a digital value
larger than a first defined value in the A/D-converted image data for one
page, by a first pixel number detecting unit. The hologram reproduction
apparatus controls a magnitude value of the image data at the time of the
A/D conversion by the first control unit so that the number of detected
pixels is within a predetermined range. Thereby, a dynamic range of the
A/D conversion to the two-dimensional modulated image data can
effectively be used. Therefore, a quantization noise due to the A/D
conversion can be reduced, and also a reproduction S/N can be improved.