Digital vtr

Abstract

A playback device for replaying a bit stream digitally transmitted which includes detecting means for detecting only intra-picture data in the bit stream that is replayed; extracting means for extracting the detected intra-picture data from the replayed bit stream, according to the result of the detection at the detecting means; replay mode designating means for selecting and designating one of normal replay, slow replay and still replay, as a replay mode; and replay data outputting means for storing the extracted intra-picture data, and outputting the detected intra-picture data as replay picture data, according to a mode signal output by said replay mode designating means.

1 . A playback device for replaying a bit stream comprised of a plurality of transport stream packets and recorded on a medium, the playback device comprising:
 a data decoding circuit for decoding at least intra-picture data from the bit stream which has been read from the medium;   a bit stream forming circuit for forming a bit stream used for fast replay using the intra-picture data decoded by the data decoding circuit; and   a buffer for storing the bit stream formed by the bit stream forming circuit to output the bit stream at a predetermined rate;   wherein the bit stream recorded on the medium is formatted into a plurality of data units, each of which comprises a predetermined number N of data segments formed by a predetermined number M of said plurality of transport stream packets, wherein M≠N and the ratio of M to N is constant.   
   
   
       2 . A playback device according to  claim 1 , further comprising:
 a speed selection circuit for selecting a speed of fast replay;   wherein the bit stream forming circuit forms a bit stream used for fast replay in accordance with the speed selected by the speed selection circuit.   
   
   
       3 . A playback device according to  claim 1 , wherein each of the transport stream packets includes a header containing information indicating a type of data contained in the corresponding packet. 
   
   
       4 . A method for replaying a bit stream comprised of a plurality of transport stream packets and recorded on a medium, the method comprising:
 decoding at least intra-picture data from the bit stream which has been read from the medium;   forming a bit stream used for fast replay using the decoded intra-picture data; and   storing the bit stream to output the bit stream at a predetermined rate;   wherein the bit stream recorded on the medium is formatted into a plurality of data units, each of which comprises a predetermined number N of data segments formed by a predetermined number M of said plurality of transport stream packets, wherein M+N and the ratio of M to N is constant.   
   
   
       5 . A method according to  claim 4 , wherein the bit stream used for fast replay is formed in accordance with a selected speed. 
   
   
       6 . A method according to  claim 4 , wherein each of the transport stream packets includes a header containing information indicating a type of data contained in the corresponding packet.