Abstract: The video signal data of one of the three primary color signals having the maximum level is adjusted with regard to the amplitude level and the DC level thereof in accordance with a predetermined control data. A difference between the adjusted video signal data and a predetermined threshold level is calculated, and the control data is corrected by ones complement of the differential data. The video signal data of the three primary color signals are adjusted respectively, with regard to the amplitude level and DC level thereof in accordance with the corrected control data. In other words, merely with respect to the digital video signal data with the maximum level, the control and brightness controls are conducted. Then, a difference between the resultant video signal data and a predetermined threshold level is obtained for adjusting the respective contrast levels of the three primary color signals by using ones complement of the obtained differential data.

Abstract: An image reproduction apparatus which converts a sampling frequency from a first frequency to a second frequency, performs interfield interpolation at a third frequency, and converts the sampling frequency from the third frequency to the first frequency, wherein the interfield-interpolation is performed at the first frequency between signals one field apart from each other. The apparatus also converts a number of vertical scanning lines to convert a high definition TV signal of the MUSE format to a signal of NTSC format, sets a scanning period used in the vertical scanning line conversion, and generates a coefficient used in the vertical scanning line conversion.

Abstract: A deflection distortion correcting circuit which produces a predetermined parabolic wave as an output of an integration circuit previously correcting data used for producing the parabolic wave.

Abstract: A device for measuring a retina reflected light amount is provided with a light source for emitting a infrared ray, an image pick-up unit for receiving the infrared ray from a light emitting range at the same position as the light source, a reading unit for reading a pupil area from a face image picked up by the image pick-up unit, and an integrating unit for integrating an amount of light represented by signals which are generated by the image pick-up unit and are located at addresses within the read pupil area. This device is applicable to a gaze detecting apparatus, and provides data which can be used in medical and psychological fields.