Apparatus for magnetic recording and reproducing digital audio data allocates upper bits and lower bits on an alternating basis among pair of tracks

• US 5,424,879 A
• Filed: 10/22/1993
• Issued: 06/13/1995
• Est. Priority Date: 10/30/1992
• Status: Expired due to Term

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Yamada, Makoto, Noguchi, Masayoshi
• Primary Examiner(s): Sniezek, Andrew L.
• Application Number:
  US08/140,320
• Time in Patent Office: 599 Days
• Field of Search: 360/29, 360/22, 360/32, 360/47, 360/48, 360/53, 360/8, 360/18, 360/10.1, 360/10.3, 371/37.4, 371/37.7, 371/40.1
• US Class Current: 360/22
• CPC Class Codes: G11B 20/10527 Audio or video recording; Data buffering arrangements G11B20/12 - G11B20/18 take precedence
• CPC Class Codes: G11B 20/1809 by interleaving
• CPC Class Codes: G11B 2220/90 Tape-like record carriers
• CPC Class Codes: G11B 2220/913 Digital audio tape [DAT] format
• 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 27/3063 Subcodes
• CPC Class Codes: G11B 5/0086 using cyclically driven heads providing segmented tracks
• CPC Class Codes: G11B 5/09 Digital recording

Abstract

A recording and/or reproducing apparatus divides long bit-length data into upper bit data and lower bit data, and records both data along with discriminating data in a manner that the upper-bit data and the lower-bit data are allocated and recorded, on an alternating basis, onto the scan start side areas and the scan end side areas of a plurality of pairs of recording tracks, in order to obtain more high-quality digital audio signal to be recorded and reproduced.

Claims

1. A recording and reproducing apparatus for recording and/or reproducing left channel and right channel audio data with a high it rate, wherein a running speed of a magnetic tape and a number of revolutions of a rotary head round which said magnetic tape is wrapped are controlled to "N" times in case of normal mode (N≧

2;

"N" is a positive integer), and processing speeds of a reproducing signal processing unit, a modulating circuit, a demodulating circuit, and a recording signal processing unit are "N" times in case of the normal mode, said recording and reproducing apparatus comprising;

dividing means for dividing quantized data a number of bits of which is "m" into upper-bit data a number of bits of which is "m₁ " and lower-bit data a number of bits of which is "m₂ " for each left and right channel;

discriminating data generating means for generating discriminating data for discriminating between said upper "m₁ " bits data and lower "m₂ " bits data;

data converting means for converting each of said upper "m₁ " bits data and lower "m₂ " bits data into "n" bits data (n≧

m₁, n>

m₂), and sequentially outputting them at said N times processing period;

recording signal generating means for interleaving an output from said data converting means at said N times interleaving period, and then converting them into recording data with error correcting codes; and

recording data recording means for forming N pairs of recording tracks having a positive or a negative azimuth angle at said N times interleaving period, and sequentially recording said recording data and discriminating data in a predetermined area onto said N pairs of recording tracks (N, m, m₁, m₂, and n are positive integers);

wherein

said data converting means further operates for setting said processing period to twice said interleaving period, and dividing each of recording tracks into a scan start side recording area and a succeeding scan end side recording area, with respect to two pairs of said recording tracks formed by said processing period;

in said two pairs of recording tracks consisting of first, second, third, and fourth recording tracks;

one of said left channel or said right channel upper-bit data of the first half of said processing period is allocated to said scan start side recording area of the first recording track, and the other of said left channel or said right channel lower-bit data of the first half of said processing period is allocated to said succeeding scan end side recording area;

said other of said left channel or said right channel upper-bit data of the first half of said processing period is allocated to said scan start side recording area of the second recording track, and said one of said left channel or said right channel lower-bit data of the first half of said processing period is allocated to the succeeding scan end side recording area;

one of said left channel or said right channel lower-bit data of the second half of said processing period is allocated the said scan start side recording area of the third recording track, and the other of said left channel or right channel upper-bit data of the second half of said processing period is allocated to the succeeding scan end side recording area; and

said other of said left channel or said right channel lower-bit data of the second half of said processing period is allocated to said scan start side recording area of the fourth recording track, and said other of said left channel or right channel upper-bit data of the second half of said processing period is allocated to the succeeding scan end side recording area.

2. A recording and reproducing apparatus according to claim 1, wherein;

said data converting means adds discriminating data from the discriminating data generating means with a redundant bit when each of upper "m₁ " bits data and lower "m" bits data is converted into "n" bits data (here, n>

m₁, n>

m₂).

3. A recording and reproducing apparatus according claim 2, further comprising:

means for reproducing said reproducing signal from said magnetic tape;

means for demodulating said reproducing signal;

signal processing means for error-correcting said demodulated reproducing signal, which is de-interleaved thereafter and is output; and

wherein

said data converting means links said upper bits and lower bits which have been separated and recorded, based on said discriminating data included in said output data.

4. A recording and reproducing apparatus according to claim 3, wherein;

said data converting means selects upper-bit data from said demodulated reproducing signal based on said discriminating data, in a variable speed reproducing mode, and outputs the selected upper-bit data.

5. A recording and reproducing apparatus according to claim 4, wherein:

said data converting means selectively inputs upper-bit data output from said reproducing apparatus in the variable speed reproducing mode, expands the received data along the time axis, and outputs the time-expanded data in the sequence as they are recorded.

6. A recording and reproducing apparatus according to claim 5, said data converting means further comprising:

a delay circuit for delaying said reproducing signal output from said reproducing means by a predetermined interleaving period and producing delayed output data; and

selective processing means for processing selectively output data from said delay circuit or said reproducing signal output from said reproducing means wherein;

in the variable speed reproducing mode, a processing object of said selective processing means is switched at said interleaving period corresponding to a reproducing speed, so that said upper-bit data provided in a sequence different from that taken for recording, are output in the sequence as they are recorded.

7. A recording and reproducing apparatus according to claim 1, wherein:

said discriminating data generating means comprises means for generating sub-code data including a sampling frequency information and a time information, and allocates the discriminating data to said sub-code data output thereafter from said discriminating data generating means;

said recording signal generating means interleave processes said sub-code data which is error-correct processed thereafter, and then converts said sub-code data into recording data; and

said recording data recording means sequentially records said recording data onto a predetermined area of said N pairs of recording tracks.

8. A recording and reproducing apparatus according to claim 1, wherein:

space="preserve" listing-type="equation">N=2, m=20, m.sub.1 =16, m.sub.2 =4, and n=16.

9. A recording and reproducing apparatus for recording and/or reproducing left channel and right channel audio data with a high bit rate, wherein a running speed of a magnetic tape and a number of revolutions of a rotary head round which said magnetic tape is wrapped are controlled to "N" times in case of normal mode (N≧

2;

"N" is a positive integer), processing speeds of a reproducing signal processing unit, a modulating circuit, a demodulating circuit, and a recording signal processing unit are "N" times in case of the normal mode, said recording and reproducing apparatus comprising;

dividing means for dividing quantized data a number of bits of which is "m" into upper-bit data a number of bits of which is "m" and lower-bit data a number of bits of which is "m" for each left and right channel;

discriminating data generating means for generating discriminating data for discriminating between said upper "m₁ " bits data and lower "m₂ " bits data;

data converting means for converting each of said Upper "m₁ " bits data and lower "m₂ " bits data into "n" bits data (n≧

m₁, n>

m₂), and sequentially outputting them at said N times processing period;

recording signal generating means for interleaving an output from said data converting means at said N times interleaving period, and then converting them into recording data with error correcting codes; and

recording data recording means for forming N pairs of recording tracks having a positive or a negative azimuth angle at said N times interleaving period, and sequentially recording said recording data and discriminating data in a predetermined area onto said N pairs of recording tracks m, m₁, m₂, and n are positive integers);

wherein;

said data converting means further operates for setting said processing period to twice said interleaving period, and dividing each of said recording tracks into a scan start side recording area and a succeeding scan end side recording area;

in two pairs of said N pairs of recording tracks consisting of first, second, third, and fourth recording tracks formed in said processing period;

one of said left channel or said right channel upper-bit data of the first half of said processing period is allocated to said scan start side recording area of the first recording track, and the other of said left channel or said right channel lower-bit data of the first half of said processing period is allocated to the succeeding scan end side recording area;

said one of said left channel or said right channel lower-bit data of the first half of said processing period is allocated to said scan start side recording area of the second recording track, and said other of said left channel or right channel upper-bit data of the first half of said processing period is allocated to the succeeding scan end side recording area;

said other of said left channel or said right channel upper-bit data of the second half of said processing period is allocated to said scan start side recording area of the third recording track, and said one of said left channel or right channel lower-bit data of the second half of said processing period is allocated to the succeeding scan end side recording area;

said other of said left channel or said right channel lower-bit data of the second half of said processing period is allocated to said scan start recording area of the fourth recording track, and said one of said left channel or said right channel upper-bit data of the second half of said processing period is allocated to the succeeding scan end side recording area; and

converting data in which said upper-bit data and lower-bit data are continuous are generated.

10. A recording and reproducing apparatus according to claim 9, further comprising:

means for reproducing said reproducing signal from said magnetic tape;

means for demodulating said reproducing signal;

signal processing means for error-correcting said demodulated reproducing data which is de-interleaved thereafter, and separating thus de-interleaved reproducing signal into sampling frequency information and reproducing data; and

wherein

said data converting means extracts discriminating data based on said sampling frequency information, and links said upper bits and said lower bits which are output thereafter.

11. A recording and reproducing apparatus according to claim 10, wherein:

said data converting means selects upper-bit data from said demodulated reproducing signal based on said discriminating data, in a variable speed reproducing mode, and outputs the selected upper-bit data.

12. A recording and reproducing apparatus according to claim 11, wherein:

said data converting means selectively receives the upper-bit data output from said reproducing circuits, expands the received data along the time, axis, and then outputs the time-expanded data in the sequence as they are recorded.

13. A recording and reproducing apparatus according to claim 12, said data converting means further comprising:

a delay circuit for delaying said reproducing signal output from said reproducing means by a predetermined interleaving period and producing delayed output data; and

selective processing means for processing selectively output data from said delay circuit or said reproducing signal output from said reproducing means, wherein;

in the variable speed reproducing mode, a processing object of said selective processing means is switched at said interleaving period corresponding to reproducing speed, so that said upper-bit data provided in a sequence different from that taken for recording, are output in the sequence as they are recorded.

14. A recording and reproducing apparatus according to claim 9, wherein:

space="preserve" listing-type="equation">N=2, m=24, m.sub.1 =16, m.sub.2 =8, and n=16.

15. A recording and reproducing apparatus for recording and/or reproducing left channel and right channel audio data with a high bit rate, wherein a running speed of a magnetic tape and a number of revolutions of a rotary head round which said magnetic tape is wrapped are controlled to "N" times in case of normal mode (N≧

2;

"N" is a positive integer), and processing speeds of a reproducing signal processing unit, a modulating circuit, a demodulating circuit, and a recording signal processing unit are "N" times in case of the normal mode, said recording and reproducing apparatus comprising;

dividing means for dividing quantized data a number of bits of which is "m" into upper-bit data a number of bits of which is "m₁ " and lower-bit data a number of bits of which is "m₂ " for each left and right channel;

discriminating data generating means for generating discriminating data for discriminating between said upper "m₁ " bits data na lower "m₂ " bits data;

data converting means for converting each of said upper "m₁ " bits data and lower "m₂ " bits data into "n" bits data (n≧

m₁, n>

m₂), and sequentially outputting them at said N times processing period;

recording signal generating means for interleaving an output from said data converting means at said N times interleaving period, and then converting them into recording data with error correcting codes; and

recording data recording means for forming N pairs of recording tracks having a positive or a negative azimuth angle at said N times interleaving period, and sequentially recording said recording data and discriminating data in a predetermined area onto said N pairs of recording tracks (N, m, m₁, m₂, and n are positive integers);

wherein;

said data converting means further operates for setting said processing period to twice said interleaving period, and dividing each of said recording tracks into a scan start side recording area and a scan end side recording area;

in two pairs of said N pairs of recording tracks consisting of first, second, third and fourth recording tracks formed in said processing period;

one of said left channel or said right channel upper-bit data of the first half of said processing period is allocated to said scan start side recording area of the first recording track, and the other of said left channel or said right channel upper-bit data of the first half of said processing period is allocated to the succeeding scan end side recording area;

said other of said left channel or said right channel lower-bit data of the first half of said processing period is allocated to said scan start side recording area of the second recording track, and said one of said left channel or said right channel lower-bit data of the first half of said processing period is allocated to the succeeding scan end side recording area;

said one of said left channel or said right channel lower-bit data of the second half of said processing period is allocated to said scan start side recording area of the third recording track, and said other of said left channel or said right channel lower-bit data of the second half of said processing period is allocated to the succeeding scan end side recording area;

said other of said left channel or said right channel upper-bit data of the second half of said processing period is allocated to said scan start side recording area of the fourth recording track, and said one of said left channel or said right channel upper-bit data of the second half of said processing period is allocated to the succeeding scan end side recording area; and

converting data in which said upper-bit data and said lower-bit data are continuous are generated.

16. A recording and reproducing apparatus according to claim 15, wherein:

space="preserve" listing-type="equation">N=2, m=24, m.sub.1 =16, m.sub.2 =8, and n=16.

17. A recording and reproducing apparatus according to claim 15, wherein:

space="preserve" listing-type="equation">N=2, m=20, m.sub.1 =15, m.sub.2 =5, and n=16.