Abstract: Jitter of a Program Clock Reference (PCR) in a transport stream of an Moving Picture Experts Group (MPEG) signal transmitted over Asynchronous Transfer Mode (ATM) system is reduced by correcting PCR to PCR−(T−&dgr;) if |PCR−STC|>T−&dgr;−&Dgr; is true and (PCR−STC)>0, correcting PCR to PCR+(T−&dgr;) if |PCR−STC|>T−&dgr;−&Dgr; is true and (PCR−STC)<0, and making no correction if −PCR−STC−>T−&dgr;−&Dgr; is false. The program clock reference received is represented by PCR, a system time clock at the time when the program clock reference is received is represented by STC, a period of a transport stream packet at an output terminal of an MPEG encoder is represented by T, a packet transmission time of the transport stream packet at an input terminal of the apparatus is represented by &dgr;, and a tolerable range is represented by &Dgr;.

Abstract: In an AAL5 jitter reduction method for an image data transmission system for converting MPEG data into ATM cells and transmitting the ATM cells through an ATM line, an addition average value of system time clocks at timings for detecting starts of adjacent transport packets after AAL5 termination is obtained. A transport packet arrival time is corrected on the basis of the obtained addition average value. An AAL5 jitter reduction apparatus is also disclosed.

Abstract: A slow motion replay system comprises a data transmitting section which adds null data to picture data at every predetermined unit to make transmission data which has N (N.gtoreq.2, N: integer) times length of the picture data. A decoding section receives the transmission data and picks out the picture data from the transmitting data to decode the picture data into decoded data. The decoding section supplies the decoded data to a display N times for every frame. The display displays each frame N times.

Abstract: An analogue audio signal input to a transmission unit 1 is band limited into a frequency band lower than that of a main signal pass with a low-pass filter 21 and then converted into a digital value with a sampling clock lower than the main signal pass by an analogue/digital converter 22. All bits of the converted digital signal are inverted by an inverter 23. The digital signal input to a reception unit 3 via a transmission channel 100 is inverted by inverter 42 and is digital/analogue converted by digital/analogue converter 43 with the sampling clock lower than the main signal pass. The resultant signal is band limited into the low frequency band through a low-pass filter 44 and then output to a level comparator 45. A low-pass filter 46 band limits the signal for the main signal pass into the low frequency bang. The level comparator 45 compares the output level of the low-pass filter 44 with that of the low-pass filter 46.