Abstract: A video signal recording and reproducing apparatus for recording a video signal whose information amount is compressed using a high-efficiency encoding employing an orthogonal transform, wherein encoded data obtained by encoding only low-frequency coefficients are recorded separately from normal encoded data. When the amount of information after compression falls short of a presdetermined amount available for recording, the encoded data of low-frequency coefficients are added to fill the vacancy. For the low-frequency coefficients, check words are appended that which provide a greater minimum distance compared with other coefficients. The low-frequency coefficients are doubly encoded for error-correction.

Abstract: A magnetic recording and reproducing apparatus wherein synchronizing separation of a reproduction video signal can be performed accurately and a stabilized reproduction video signal can be obtained. The magnetic recording and reproducing apparatus includes a switch device for selectively inserting, upon recording, a PCM modulated audio signal into a blanking period of an FM modulated video signal, a PCM region signal generator for identifying a region of a PCM modulated audio signal in a reproduction signal reproduced by a rotary head and generating a control signal representative of a PCM audio signal region, an FM demodulator for FM demodulating a reproduction signal from the rotary head into a reproduction FM demodulation signal, and a clip circuit for clipping a lower end portion of a PCM audio signal region of a reproduction FM demodulation signal from the FM demodulator in accordance with a control signal generated from the PCM region signal generator.

Abstract: When recording HD video signals, twice the number of tracks are used as compared to recording the conventional NTSC video signals, and video signals are recorded in the audio sector. HD video signals are encoded with the same number of checks as the error-correcting code of the present video signals, with the number of information symbols being increased. When recording HD video signals and present video signals, these signals are encoded so that the shortest recording wavelength is the same with either signal.

Abstract: A magnetic recording and reproducing apparatus wherein synchronizing separation of a reproduction video signal can be performed accurately and a stabilized reproduction video signal can be obtained. The magnetic recording and reproducing apparatus includes a switch device for selectively inserting, upon recording, a PCM modulated audio signal into a blanking period of an FM modulated video signal, a PCM region signal generator for identifying a region of a PCM modulated audio signal in a reproduction signal reproduced by a rotary head and generating a control signal representative of a PCM audio signal region, an FM demodulator for FM demodulating a reproduction signal from the rotary head into a reproduction FM demodulation signal, and a clip circuit for clipping a lower end portion of a PCM audio signal region of a reproduction FM demodulation signal from the FM demodulator in accordance with a control signal generated from the PCM region signal generator.

Abstract: Specified modular arithmetic is applied to input digital data to divide the input data into two main codes and a subcode. Otherwise, input digital data is divided into two pieces of digital data according to a specified rule. The digital data is divided so that the original input digital data can be completely restored if the two main codes and the subcode or both of the divided data are used, and the original input digital data can be nearly correctly restored even when one of the main codes or one of the divided data is used.