PCM signal recording system

• US 5,260,840 A
• Filed: 03/16/1992
• Issued: 11/09/1993
• Est. Priority Date: 03/18/1991
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Hatanaka, Yuji, Takeuchi, Toshifumi, Arai, Takao
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Clark, Jhihan
• Application Number:
  US07/851,879
• Time in Patent Office: 603 Days
• Field of Search: 360/48, 360/32, 360/47, 360/53, 360/19.1, 360/33.1
• US Class Current: 360/48
• CPC Class Codes: G11B 20/10527 Audio or video recording; Data buffering arrangements G11B20/12 - G11B20/18 take precedence
• CPC Class Codes: G11B 20/1262 with more than one format/standard, e.g. conversion from CD-audio format to R-DAT format
• CPC Class Codes: G11B 20/1809 by interleaving
• CPC Class Codes: G11B 20/1876 Interpolating methods
• CPC Class Codes: G11B 2020/1087 wherein a selection is made among at least two alternative ways of processing
• CPC Class Codes: G11B 2020/10879 the kind of record carrier being the selection criterion
• CPC Class Codes: G11B 2220/90 Tape-like record carriers
• CPC Class Codes: G11B 5/00839 using cyclically driven heads providing segmented tracks
• CPC Class Codes: G11B 5/00891 formats only, e.g. analog and digital
• CPC Class Codes: H04N 5/78213 involving recording in different depths of the magnetic tape
• CPC Class Codes: H04N 5/928 the sound signal being pulse code modulated and recorded in time division multiplex with the modulated video signal
• CPC Class Codes: H04N 9/802 involving processing of the sound signal H04N9/806, H04N9/835 take precedence

Abstract

A segmentation system in which, in recording a PCM audio signal on a magnetic tape or the like, a signal divided in 5 per field is divided into 4 segments per field with high capabilities of error correction and a mean value interpolation for burst errors etc. Regarding the signal of a deep-layer record PCM format, in which each subframe (3 in FIGS. 1(a)-1(c)) is formed of 30 blocks of only even data or odd data and in which data frames (4) each including 1 subframe of the even data and 1 subframe of the odd data in combination are formed in the number of 5 per frame, the even data items are arranged in the first half part of a PCM record area on the tape, and the odd data items in the latter half part. Further, each superblock (1) is constituted by 2 blocks adjacent to each other, a C2 parity (22) of 3 superblocks being an error correcting parity is extracted from 1 subframe, with every 4 of the remaining 12 superblocks forming 1 area block (2), and the 3 area blocks are located in 3 segments differing from one another. In the case where the PCM audio signal is recorded by an HD VTR or the like by utilizing the signal processing of the deep-layer record PCM format, the segmentation warrants high capabilities for mean value interpolation and error correction for burst errors etc.

Claims

1. A PCM signal recording system which records a digital signal on a recording medium by the use of recording heads, comprising:

signal processing means to generate M data frames (where M denotes an integer of at least

     2) every predetermined period T from digital data indicative of sample values of a signal to be recorded within said period T;

said M data frames being generated such that said digital data is divided into M data pieces of M time units, that each of the resulting data piece within each time unit is sub-divided into two, even data item E corresponding to the even-numbered samples and odd data item O corresponding to the odd-numbered samples, and that each of said data frames is formed by a selected combination of said even data item E, said odd data item O and an error correcting code C attached to the both data items; and

segmentation means to rearrange said M data frames generated from said signal processing means, into N segments (where N denotes an integer of at least 2 differing from said integer M);

the segmentation being performed such that each of said even data E, said odd data O and said error correcting code C of each of said M data frames is divided into a plurality of elements, that the elements of all the even data items E, those of all the odd data items O and those of all the error corresponding codes C are respectively distributed into N groups, and that each of said segments is formed by combining the corresponding ones of said groups of said even data items E, said odd data items O and said error correcting codes C, while locating said error correcting code C between said corresponding groups of said even data items E and said odd data items O.

2. A PCM signal recording system as defined in claim 1, wherein said integer M is equal to 5, while said integer N is equal to 8.

3. A PCM signal recording system as defined in claim 1, wherein said segmentation means divides said even data item E into three elements E1, E2 and E3, while dividing said odd data item O into three elements O1, O2 and O3.

4. A PCM signal recording system as defined in claim 3, wherein the elements of said even data item E and the corresponding elements of said odd data item O, said even and odd data items in the same time unit, are contained in segments different from each other.

5. A PCM signal recording system as defined in claim 3, wherein said segmentation means causes said three elements E1, E2 and E3 of said even data item E to be stored in three segments different from one another and also causes said three elements O1, O2 and O3 of said odd data item O to be stored in three segments different from one another.

6. A PCM signal recording system as defined in claim 2, wherein an error correction is completed with three of said eight segments.

7. A PCM signal recording system as defined in claim 6, wherein a case coexists where an error correction is completed with four of said eight segments.

8. A PCM signal recording system as defined in claim 3, wherein said each data frame is composed of said even data item of 24 blocks, said odd data item of 24 blocks and said error correcting code of 12 blocks;

each of said elements of said even data item and said odd data item is composed of 8 blocks;

each of said elements of said error correcting code is composed of 2 blocks; and

said each segment is composed of 2 elements of said even data item 2 elements of said odd data item and 4 elements of said error correcting code.

9. A PCM signal recording system as defined in claim 8, wherein 2 blocks constitute a super block, and the superblocks belonging to the different elements are located in adjacency to each other within said segment.

10. A PCM signal recording system as defined in claim 1, wherein said each segment has an area of fixed length which stores therein the elements of said even data item and said odd data item and the elements of said error correcting code, and dummy data is stored in a part of said area to which no element is assigned.

11. A PCM signal recording system as defined in claim 1, wherein said each segment has an area of fixed length which stores therein the elements of said even data item and said odd data item and the elements of said error correcting code, and the same element located in a part of said area is stored in another part of said area to which no element is assigned.

12. A PCM signal recording system as defined in claim 1, wherein said signal to be recorded is an audio signal, said digital signal is a PCM audio signal, said recording heads are rotary heads, and said recording medium is a magnetic tape.