Apparatus and method for recording or reproducing digital data using speed information

An apparatus for controlling recording in a video cassette tape recorder comprising:

• frame extracting means for receiving compressed digital data input thereto and extracting specific data for a speed-varied reproduction from said compressed digital data;
• frame recording position controlling means for generating a multiplexing timing signal and multiplexing said compressed digital data and said extracted specific data from said frame extracting means based on said multiplexing timing signal;
• frame position information recording means for recording index information and position information of specific tracks for recording said specific data for the speed-varied reproduction on a magnetic tape based on said multiplexing timing signal;
• and
• digital recording means for recording digital signals including said digital data and specific data from said frame recording position controlling means on the magnetic tape.

A method for controlling recording and reproduction in a video cassette tape recorder, comprising the steps of:

• extracting specific data for a speed varied reproduction from compressed digital data;
• calculating a number of tracks for recording said digital data and outputting a multiplexing timing signal based on said calculated number of tracks;
• recording position information of specific tracks for the speed varied reproduction and index information on a magnetic tape based on said multiplexing timing signal;
• recording digital signals including said digital data and said index information on the magnetic tape;
• reproducing said digital signals recorded on the magnetic tape;
• detecting said position information of the specific tracks for the speed varied reproduction and said index information;
• controlling the speed of a capstan motor based on said detected index information and position information of the specific tracks;
• and
• removing unnecessary bit streams from said specific data.

A method of controlling recording in a video cassette tape recorder, comprising the steps of:

• extracting specific data for a speed-varied reproduction from compressed digital data;
• generating a multiplexing timing signal and multiplexing said compressed digital data and said extracted specific data based on said multiplexing timing signal;
• recording index information and position information of specific tracks for recording said specific data for the speed-varied reproduction on a magnetic tape based on said multiplexing timing signal;
• and
• recording digital signals including said multiplexed digital data and specific data on the magnetic tape.

A method for processing a digital signal stored on a digital storage medium, the method performed by at least one device and comprising:

• receiving digital data,
• wherein the digital data includes video data compressed as at least one of intra-frame and predictive frame, stuffing data capable of being detected and removed, synchronous signals, and at least one relative position information associated with an I-frame, wherein the relative position information indicates position information associated with the I-frame relative to position information associated with a current frame;
• detecting the synchronous signals for decoding the video data;
• obtaining the video data from the digital data by removing the stuffing data based on stuffing code information;
• determining a position associated with the I-frame by using the relative position information;
• determining whether a speed-varied reproduction mode is selected for reproduction of the video data in a varied speed;
• and
• reproducing the video data based on the determined position associated with the I-frame, the synchronous signals, and a result of the step of determining whether the speed-varied reproduction mode is selected.