Transmission, recording and reproduction of digital data and time information in transport packets using a compression ratio

• US 5,859,949 A
• Filed: 05/22/1997
• Issued: 01/12/1999
• Est. Priority Date: 11/14/1994
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Yanagihara, Naofumi
• Primary Examiner(s): TRAN, THAI Q
• Application Number:
  US08/862,065
• Time in Patent Office: 600 Days
• Field of Search: 348/423, 348/384, 348/390, 386/33, 386/111, 386/112, 386/95, 386/98, 386/68, 386/81-82
• US Class Current: 386/314
• CPC Class Codes: G11B 15/125 conditioned by the operating function of the apparatus
• CPC Class Codes: G11B 15/1875 adaptations for special effects or editing signal processing or indexing therefor G11B27/00
• CPC Class Codes: G11B 15/4671 by controlling simultaneously the speed of the tape and the speed of the rotating head
• CPC Class Codes: G11B 15/4678 superimposed on the main signal track
• CPC Class Codes: G11B 15/4733 with provision for information tracking, e.g. for time base correction
• CPC Class Codes: G11B 2220/90 Tape-like record carriers
• CPC Class Codes: G11B 27/005 Reproducing at a different information rate from the information rate of recording for television signals H04N5/783
• CPC Class Codes: G11B 27/3027 used signal is digitally coded
• CPC Class Codes: G11B 27/3036 Time code signal
• CPC Class Codes: G11B 27/3063 Subcodes
• CPC Class Codes: G11B 5/0086 using cyclically driven heads providing segmented tracks
• CPC Class Codes: H04N 21/4135 external recorder interface circuits between an apparatus for recording television signals and a television receiver H04N5/775
• CPC Class Codes: H04N 21/4305 Synchronising client clock from received content stream, e.g. locking decoder clock with encoder clock, extraction of the PCR packets arrangements for synchronising receiver with transmitter by comparing receiver clock with transmitter clock H04L7/0012; arrangements for synchronising receiver with transmitter wherein the receiver takes measures against momentary loss of synchronisation H04L7/0083
• CPC Class Codes: H04N 21/4325 by playing back content from the storage medium reproduction of recorded television signals H04N5/76; reproduction of recorded television signals H04N9/79
• CPC Class Codes: H04N 21/4334 Recording operations recording of a television signal H04N5/76; arrangements for recording or accumulating broadcast information or broadcast-related information H04H60/27
• CPC Class Codes: H04N 21/4344 Remultiplexing of multiplex streams, e.g. by modifying time stamps or remapping the packet identifiers
• CPC Class Codes: H04N 21/4402 involving reformatting operations of video signals for household redistribution, storage or real-time display details of conversion of video standards at pixel level H04N7/01; video transcoding H04N19/40; adapting incoming signals to the display format of the display terminal G09G5/005; media handling at the source in data packet switching networks H04L65/764
• CPC Class Codes: H04N 5/78263 for recording on tracks inclined relative to the direction of movement of the tape
• CPC Class Codes: H04N 5/783 Adaptations for reproducing at a rate different from the recording rate
• CPC Class Codes: H04N 5/9262 using predictive coding
• CPC Class Codes: H04N 5/9264 : using transform coding
• CPC Class Codes: H04N 7/56 : Synchronising systems therefor
• CPC Class Codes: H04N 9/7921 : for more than one processing mode
• CPC Class Codes: H04N 9/797 : for recording the signal in a plurality of channels, the bandwidth of each channel being less than the bandwidth of the signal H04N9/804, H04N9/81, H04N9/82 take precedence
• CPC Class Codes: H04N 9/8042 : involving data reduction
• CPC Class Codes: H04N 9/8227 : the additional signal being at least another television signal

Abstract

A data packet which contains time information is time compressed and the time information is extracted from the time compressed data packet. A system clock is synchronized with the extracted time information and is multiplied by a predetermined compression ratio to produce replacement time information which replaces the time information in the time compressed data packet. The time compressed data packet that now contains the replacement time information is modulated and transmitted or recorded.

Claims

1. A data reproducing apparatus for reproducing a time compressed data packet, comprising:

means for reproducing said data packet which was time compressed at a predetermined compression ratio, said data packet containing time information which replaced original time information originally present in said data packet prior to time compression thereof, said time information having been generated by multiplying a reference clock by said predetermined compression ratio such that said data packet is read out at a speed dependent upon said compression ratio;

a memory for buffering said reproduced data packet;

a capture circuit for recovering said time information from said reproduced data packet; and

a controller for controlling the buffering of said reproduced data packet in accordance with said recovered time information.

2. A data reproducing method for reproducing a time compressed data packet, said method comprising the steps of:

reproducing said data packet which was time compressed at a predetermined compression ratio, said data packet containing time information which replaced original time information originally present in said data packet prior to time compression thereof, said time information having been generated by multiplying a reference clock by said predetermined compression ratio such that said data packet is read out at a speed dependent upon said compression ratio;

buffering said reproduced data packet;

recovering said time information from said reproduced data packet; and

controlling the buffering of said reproduced data packet in accordance with said recovered time information.