Abstract: An electronic still camera which photographs an object by image pickup means such as a solid image pickup element or the like and records the video signal of the object into a rotary recording medium such as a magnetic disc or the like. The electronic still camera includes a mechanical shutter and an electronic shutter function to control electrically the accumulation time of the image pickup means and it is adapted such that, when the shutter speed is slower than a predetermined value, it controls a time for exposure to the image pickup means by the mechanical shutter and, when the shutter speed is higher than the predetermined value, it controls the exposure time to the image pickup means by means of the electronic shutter function and also controls the mechanical shutter to remain open at least for the exposure time.

Abstract: A digital signal magnetic recording/reproducing apparatus converts a digital signal into multi-value digital signals and performs recording/reproducing of a multi-value quadrature amplitude-modulated signal. By using the multi-value quadrature amplitude modulation, it is possible to remove the DC component in the recording signal and improve the utilization efficiency of the recording frequency band. Further, using a system to memorize the frequency characteristic of the magnetic recording/reproducing unit and effect Viterbi decoding regarding the intersymbol interference caused by the frequency as a convolutional coding, it is possible to detect the level without necessitating frequency equalization. Accordingly, there arises no deterioration of the S/N ratio by frequency equalization. Furthermore, by providing an encoder for error control coding by increasing the number of multi-values and a corresponding decoder, the error rate can be improved against the deterioration of the S/N ratio.