U.S. patent number RE37,808 [Application Number 09/513,696] was granted by the patent office on 2002-07-30 for disc recording medium having subsidiary data in which is stored an identifier.
This patent grant is currently assigned to Sony Corporation. Invention is credited to Teppei Yokota.
United States Patent |
RE37,808 |
Yokota |
July 30, 2002 |
**Please see images for:
( Certificate of Correction ) ** |
Disc recording medium having subsidiary data in which is stored an
identifier
Abstract
A disc-shaped recording medium and a reproducing apparatus for
the disc-shaped recording medium in which the letter information,
such as a title, pertinent to a program recorded on the disc-shaped
recording medium, is recorded as subsidiary data in a management
area or in a program area. In the subsidiary data, there is
recorded an identified for specifying whether or not the subsidiary
data is allowed to be duplicated on an other recording medium so
that inhibition or permission of duplication of the subsidiary
information may be controlled at the time of duplication of the
program.
Inventors: |
Yokota; Teppei (Chiba,
JP) |
Assignee: |
Sony Corporation (Tokyo,
JP)
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Family
ID: |
18104873 |
Appl.
No.: |
09/513,696 |
Filed: |
February 24, 2000 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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Reissue of: |
753675 |
Nov 27, 1996 |
05825731 |
Oct 20, 1998 |
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Foreign Application Priority Data
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Jul 12, 1995 [JP] |
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7-318956 |
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Current U.S.
Class: |
369/47.12;
369/53.21 |
Current CPC
Class: |
G11B
27/3063 (20130101); G11B 27/329 (20130101); G11B
20/00688 (20130101); G11B 20/00086 (20130101); G11B
27/105 (20130101); G11B 2020/10592 (20130101); G11B
27/34 (20130101); G11B 7/00745 (20130101); G11B
2220/2545 (20130101); G11B 7/0037 (20130101) |
Current International
Class: |
G11B
27/10 (20060101); G11B 27/30 (20060101); G11B
27/32 (20060101); G11B 20/00 (20060101); G11B
27/34 (20060101); G11B 027/22 () |
Field of
Search: |
;369/48,47.1,47.12,47.14,47.15,32,33,59.1,54,58,275.3,53.21 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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4312922 |
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Oct 1993 |
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DE |
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0406021 |
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Jan 1991 |
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EP |
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0553545 |
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Aug 1993 |
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EP |
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0626689 |
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Nov 1994 |
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EP |
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0635835 |
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Jan 1995 |
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EP |
|
0668695 |
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Aug 1995 |
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EP |
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95/12200 |
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May 1995 |
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WO |
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Primary Examiner: Dinh; Tan
Attorney, Agent or Firm: Oblon, Spivak, McClelland, Maier
& Neustadt, P.C.
Claims
What is claimed is:
1. A .[.disc.]. reproducing apparatus for reproducing .[.from a
disc.]. main data, management data for managing the main data, and
subsidiary data ancillary to the main data, comprising: readout
means for reading out the main data, the management data, and the
subsidiary data from .[.the disc.]. .Iadd.a recording
medium.Iaddend.; outputting means for digitally outputting the main
data and the subsidiary data; detection means for detecting a flag
specifying one of inhibition and permission of digitally outputting
the subsidiary data read out by the readout means; and control
means for controlling one of the inhibition and permission of
digitally outputting the subsidiary data by the outputting means in
accordance with the flag detected by the detection means, so as to
prevent copying of the subsidiary data to another medium.
2. The .[.disc.]. reproducing apparatus as claimed in claim 1
wherein the .[.disc-shaped.]. recording medium is made up of a
management area and a program area; said management area has the
subsidiary data and the management data recorded therein; and
wherein outputting of the subsidiary data by the outputting means
is one of inhibited and permitted based on a flag specifying one of
the inhibition and permission of the digital output included in the
subsidiary data recorded in the management area.
3. The .[.disc.]. reproducing apparatus as claimed in claim 1
wherein the .[.disc-shaped.]. recording medium is made up of a
management area and a program area; said management area has the
subsidiary data and the management data recorded therein; said
program area has recorded therein said subsidiary data along with
the main data; and wherein outputting of the subsidiary data by the
outputting means is one of inhibited and permitted based on a flag
specifying one of inhibition and permission of the digital output
included in the subsidiary data recorded in the program area.
4. The .[.disc.]. reproducing apparatus as claimed in claim 1
wherein the subsidiary data is letter information concerning the
.[.disc-shaped.]. recording medium and the program recorded on the
.[.disc-shaped.]. recording medium.
5. The .[.disc.]. reproducing apparatus as claimed in claim 1
wherein the main data is audio data and wherein said subsidiary
data is at least one of the name of the .[.disc-shaped.]. recording
medium, name of the performer, name of the composer, name of the
lyricist, name of the arranger, name of the publisher and date of
production.
6. In a .[.disc-shaped.]. recording medium comprising main data,
management data for managing the main data, and subsidiary data
ancillary to the main data, the improvement comprising: a flag
present in the subsidiary data, said flag being digitally outputted
by a .[.disc.]. reproduction apparatus and being capable of
detection by the .[.disc.]. reproduction apparatus for one of
inhibiting and permitting duplication of subsidiary data present on
the .[.disc.]. .Iadd.recording medium.Iaddend..
7. The .[.disc-shaped.]. recording medium as claimed in claim 6
wherein the recording medium is made up of a management area and a
program area, said management area has the subsidiary data and the
management data recorded therein, and wherein the identifier for
one of inhibiting and permitting duplication of said subsidiary
data is included in the subsidiary data recorded in the management
area.
8. The .[.disc-shaped.]. recording medium as claimed in claim 6
wherein the recording medium is made up of a management area and a
program area, said management area has the subsidiary data and the
management data recorded therein, said subsidiary data is recorded
along with the main data in said program area, and wherein the
identifier for one of inhibiting and permitting duplication of said
subsidiary data is included in the subsidiary data recorded in the
program area.
9. The .[.disc-shaped.]. recording medium as claimed in claim 6
wherein the subsidiary data is the letter information concerning
the .[.disc-shaped.]. recording medium and the program recorded on
the .[.disc-shaped.]. recording medium.
10. The .[.disc-shaped.]. recording medium as claimed in claim 6
wherein the main data is audio data and wherein said subsidiary
data is at least one of the name of the .[.disc-shaped.]. recording
medium, name of the performer, name of the composer, name of the
lyricist, name of the arranger, name of the publisher and date of
production..Iadd.
11. A method for transmitting from a recording medium main data and
subsidiary data ancillary to the main data, the method comprising
the steps of: detecting a flag specifying one of inhibition and
permission of digitally outputting the subsidiary data from the
recording medium, and controlling one of inhibition and permission
of digitally outputting the subsidiary data in accordance with the
detected flag so as to prevent copying of the subsidiary data to
another medium..Iaddend..Iadd.
12. The method as claimed in claim 11 wherein the step of detecting
a flag comprises the step of: detecting a flag included in the
subsidiary data..Iaddend..Iadd.
13. The method as claimed in claim 11 wherein the step of detecting
a flag specifying one of inhibition and permission of digitally
outputting the subsidiary data comprises the step of: detecting a
flag stored in the recording medium..Iaddend..Iadd.
14. The method as claimed in claim 11 wherein the step of
controlling one of inhibition and permission of digitally
outputting the subsidiary data is based on a flag specifying one of
inhibition and permission of digitally outputting the subsidiary
data..Iaddend..Iadd.
15. The method as claimed in claim 11 wherein the subsidiary data
is letter information concerning the recording medium and the
program recorded on the recording medium..Iaddend..Iadd.
16. The method as claimed in claim 11 wherein the main data is
audio data and wherein said subsidiary data is at least one of the
name of the recording medium, name of the performer, name of the
composer, name of the lyricist, name of the arranger, name of the
publisher and date of production..Iaddend..Iadd.
17. A method for reproducing from a recording medium main data,
management data for managing the main data, and subsidiary data
ancillary to the main data, comprising the steps of: reading out
the main data, the management data, and the subsidiary data from a
recording medium; digitally outputting the main data and the
subsidiary data; detecting a flag specifying one of inhibition and
permission of digitally outputting the subsidiary data; and
controlling one of the inhibition and permission of digitally
outputting the subsidiary data in accordance with the detected flag
so as to prevent copying of the subsidiary data to another
medium..Iaddend..Iadd.
18. The method as claimed in claim 17 wherein the recording medium
is made up of a program area and a management area having the
subsidiary data and the management data recorded therein, and
wherein the step of outputting of the subsidiary data is one of
inhibited and permitted based on a flag specifying one of the
inhibition and permission of digitally outputting included in the
subsidiary data recorded in the management area..Iaddend..Iadd.
19. The method as claimed in claim 17 wherein the recording medium
is made up of a management area having the subsidiary data and the
management data recorded therein, and a program area having the
subsidiary data and the main data recorded therein, and wherein the
step of outputting of the subsidiary data one of inhibited and
permitted based on a flag specifying one of inhibition and
permission of digitally outputting included in the subsidiary data
recorded in the program area..Iaddend..Iadd.
20. The method as claimed in claim 17 wherein the subsidiary data
is letter information concerning the recording medium and the
program recorded on the recording medium..Iaddend..Iadd.
21. The method as claimed in claim 17 wherein the main data is
audio data and wherein said subsidiary data is at least one of the
name of the recording medium, name of the performer, name of the
composer, name of the lyricist, name of the arranger, name of the
publisher and date of production..Iaddend.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a disc reproducing apparatus for
reproducing a disc-shaped recording medium.
2. Description of the Related Art
In a reproducing apparatus for a compact disc (CD), which is a
disc-shaped recording medium having the audio information recorded
thereon, various sorts of indication based on the disc reproducing
information are used for enhancing convenience in use.
It has been known to reproduce and display the program number, that
is called track number, recorded on a Q-channel subcode as later
explained as a mode 1, or the elapsed time allocated to each track
number, as the display information based on the disc reproducing
information in a conventional CD reproducing apparatus.
FIG. 1 shows an example of an optical disc, such as CD.
Referring to FIG. 1, an optical disc 101 has a center aperture 102
and, looking from the inner rim towards the outer rim of the disc
101, includes a lead-in area 103, as a table-of-contents (TOC) area
or a program management area, a program area 104 having program
data recorded therein, and a program end area or a so-called
lead-out area 105. In an audio reproducing optical disc having the
audio information recorded therein, audio data is recorded in the
program area 104, while the total recording time, the total number
of recorded programs and the program-based recording time and so
forth, are managed by the lead-in area 103. When the readout of the
audio data in the program area 104 by the disc reproducing
apparatus has come to a close, and an optical pickup has reached
the lead-out area 105, the disc reproducing apparatus completes the
reproducing operation for the optical disc designed for audio
reproduction.
FIG. 2 shows an example of the above-described disc reproducing
apparatus.
The disc reproducing apparatus reads out the audio data of the
optical disc 101 designed for audio reproduction with an optical
pickup 102 and processes the audio data with a digital signal
processing circuit 116 to generate playback data which is outputted
at a digital signal output terminal 125 or at left and right
channels of an analog signal output terminal, not shown.
The optical pickup 112 of the disc reproducing apparatus reads out
the audio data of the optical disc 101, that is the so-called RF
signals, and sends the signals to an analog waveform shaping
circuit 114, while sending a focusing servo signal to a focusing
servo circuit 120 and sending tracking servo signals and thread
servo error signals to a tracking servo circuit 121.
The analog waveform shaping circuit 114 shapes the waveform of the
RF signals from the pickup 112 and sends the shaped signals to a
synchronization detection circuit 115 and a clock generating
circuit 117. The clock generating circuit 117 generates reproducing
clocks for the RF signals based on the RF signals from the analog
waveform shaping circuit 114. The generated reproducing clocks are
sent to the synchronization detection circuit 115, digital signal
processing circuit 116 and to a rotation servo circuit 122. The
synchronization detection circuit 115 detects a frame
synchronization pattern from the RF signals and sends the signal,
from which frame synchronization pattern has been detected, to the
digital signal processing circuit 116. The digital signal
processing circuit 116 decodes the RF signals, from which the frame
synchronization pattern from the digital signal processing circuit
116 has been detected, based on the reproducing clocks from the
clock generating circuit 117 and reference clocks sent from the
quartz oscillator 119, and sends the decoded signals to a subcoding
detection circuit 118, a D/A conversion circuit 123 and to a
digital signal output terminal 125. The D/A conversion circuit 123
converts the digital signals into analog signals which are sent to
an audio amplifier 124. The audio amplifier 124 amplifies the
analog audio signal from the D/A conversion circuit 123 and send
the amplified signal to the right and left channels of the analog
signal output.
The subcoding detection circuit 118 detects data of subcode P and Q
channels, as later explained, and sends the data of the respective
channels to the tracking and thread servo circuit 121.
The subcoding detection circuit 118 detects data of the subcode P
and Q channels from the digital signal of the digital signal
processing circuit 116 and sends the data of the respective
channels to a tracking and thread servo circuit 121.
The focusing servo circuit 120 generates a focusing operation
driving signal, based on the focusing error signal from the optical
pickup 112, and sends the focusing operation driving signal to the
pickup 112 for controlling the focusing operation of the optical
pickup 112. The rotation servo circuit 122 generates a rotation
driving control signal, based on playback clocks from the clock
generating circuit 117 and the reference clocks from the quartz
oscillator 119, and sends the rotation driving control signal to
the spindle motor 113 for controlling the rotational operation of
the spindle motor 112.
The tracking and thread servo circuit 121 generates tracking
control driving signals based on the tracking servo error signals
and the thread servo error signals from the pickup 112 and sends
the generated tracking control driving signals to the pickup 112
for controlling the tracking operation of the pickup 112. The
tracking and thread servo circuit 121 generates track position
control signals based on data from the P and Q channels supplied
from the subcoding detection circuit 118 and sends the position
control signals to the pickup 112 for controlling the track
positions of the pickup 112 for the programming mode.
The data of the subcode and the P and Q channels as described above
are now explained.
The signals recorded on the optical disc designed for audio
reproduction are sampled with the sampling frequency of 44.1 kHz,
with each sample or word being of 16 bits. The 16-bit-per-word
sampled data is split into a symbol of upper 8 bits and another
symbol of lower 8 bits and error correction coded or scrambled on
the symbol basis so that every 24 symbols of the data make up a
frame. This corresponds to 12 original samples, that is 6 samples
each of the stereo left and stereo right channels.
The signals assembled into one such frame are of such a format in
which each frame 135 has a synchronization pattern data area 131 of
24 channel bits, a subcoding area 132 of 14 channel bits, a program
data area 133, a parity data area 134, another program data area
133 and another parity data area 134. The program data area 133 is
made up of 12 symbols D1 to D12 each being of 14 channel bits,
while the parity data area 134 is made up of parity data P1 to P4
each being of 14 channel bits. The areas or data portions are
interconnected by junction areas each being of 3 channel bits.
Thus, each frame 135 is made up of a sum total of 588 channel bits
of data.
FIG. 4 shows 98 of the above frames 135 collected together and
re-arrayed so that the above areas and data portions of each frame
will be contiguous to one another in the vertical direction. The
set of data shown in FIG. 4 in its entirety is also termed a frame.
However, for distinction from the frame made up of 588 channel
bits, the set of data of FIG. 4 in its entirety, made up of 98
frames, is termed a subcoding frame. This subcoding frame is made
up of a frame synchronization pattern portion 136, a subcoding
portion 137 and a data/parity portion 138. The subcoding frame is
equivalent to 1/75 second of the usual CD reproducing time.
The subcoding data, inclusive of the P-channel data and the
Q-channel data sent from the subcoding detection circuit 118 of
FIG. 12, is recorded on the subcoding portion 137 of FIG. 4. The
subcoding portion 137 is of a structure such that 98 frames of from
frame F0 to frame F98 make up one block, that is the above
subcoding frame, as shown in FIG. 15. The frames F01 and F02 are
block synchronization patterns, while representing out-of-rule
patterns S0 and S1 of the eight-to-fourteen modulation (EFM)
system. The subcoding detection circuit 118 detects the above
synchronization patterns to form a one block of the subcoding
portion 137. The respective bits of the that frames form frame F01
to frame F98 make up channels of from channel P to channel W. For
example, the P-channel is constituted by portions of the patterns
S0 and S i and P01 to P98.
The data of the six channels of from channel R to channel W are
used for special uses, such as still pictures or representation of
karaoke letters. The data of the P-channel and the Q-channel are
used for controlling the pickup track position control, that is for
controlling the accessing operation for the pickup.
The P-channel is used exclusively for recording a signal .ae
butted.0' in the lead-in area 103, a signal .ae butted.1' and a
signal .ae butted.0' between the music and music and otherwise in
the program area 104, respectively, and a signal repeated between
.ae butted.0' and .ae butted.1' at a pre-set period in the lead-out
area 105. The P-channel information is used as the information for
locating the program leading end portion.
The Q-channel information is used as the address information used
by the pickup 112 of FIG. 2 to perform the above accessing
operation. Each block of the Q-channel, that is each subcoding
frame, has a structure made up of a synchronization bit block 141,
a control bit block 142, an address bit block 143, a data bit block
144 and a cyclic redundancy code (CRC) bit block 145, as shown in
FIG. 6.
The synchronization bit block 141 is made up of 2-bit data for
recording a portion of the synchronization pattern. The control bit
block 142 includes 4-bit data for recording the number of audio
channels, emphasis or data used for identifying digital data. The
4-bit control bit data in the control bit block 142, that is the
control bit data, is now explained. FIG. 7 shows the 4-bit control
bit data. In the control bit data 142a, "0000" denotes 2-channel
audio without preemphasis. In the control bit data 142b, "1000"
denotes 4-channel audio without pre-emphasis. In the control bit
data 142c, "0001" denotes 2-channel audio with pre-emphasis. In the
control bit data 142d, "1001" denotes 4-channel audio data with
pre-emphasis. In the control bit data 142e, "0100" denotes a data
track other than an audio track in a data read-only optical disc,
such as a CD-ROM.
In FIG. 6, the address bit block 143 has 4-bit data for recording a
control signal specifying the format or a sort of data in the data
bit block 144.
In FIG. 6, the data bit block 144 has 72-bit data. If, for example,
the address bit is "0001", the data bit block 144 is made up of a
program number portion 151, an index portion 152, an elapsed time
minute component portion 153, an elapsed time second component
portion 154, an elapsed time frame number portion 155, a 0-portion
156, an absolute time minute component portion 157, an absolute
time second component portion 158 and an absolute time frame number
portion 159, as shown in FIG. 8. Each portion is comprised of 8-bit
data. Meanwhile, a frame of the frame number recorded in the
elapsed time frame number portion 155 and in the absolute time
frame number portion 159 denotes the subcoding frame.
The program number portion is represented by two digits in the
binary coded decimal notation. For example, "00" denotes a at a
beginning portion of data readout, that is a so-called lead-in
track, while "01" to "99" denote the program numbers. The number in
the hexadecimal notation "AA" denote data read-out end, that is a
so-called lead-out track. In the following description, a suffix
"h" is appended to a number represented in hexadecimal notation
such as, for example, "AAh".
The index portion 152 is represented by two-digit BCD. For example,
"00" denotes transient stop, that is pause, while "00" to "99"
denote finer divisions of the program unit.
The elapsed time hour component portion 153, the elapsed time
second component portion 154 and the elapsed a time frame number
portion 155 denote the elapsed time in the track each by two
digits, that is a sum total of 6 digits. Since one second is 75
frames, the elapsed time frame portion 155 is represented by "00"
to "74". The elapsed time frame number is decremented between
tracks so that the number will start from zero at the initial
position of each track. The 0-portion 156 is stuffed with "0"s.
The absolute time hour component portion 157, absolute time second
component portion 158 and the absolute time frame number portion
159 are each represented by 2-digit BCD, totaling at 6-digit BCD.
In the lead-in area 103 of FIG. 1, if the index portion 152 is
"A0h", the absolute time component portion 157 is represented by
the first program number, whereas, if the index portion 152 is
"A1h" "A1h", the absolute hour component portion 157 is represented
by the last program number. Both in case the index portion 152 is
"A0h" and in case the index portion 152 is "A1h", the absolute time
second component portion 158 and the absolute time frame number
portion 159 are both "0". If the index part 152 is "A2h", the
absolute time with which the lead-out area 105 of FIG. 1 starts is
recorded in the absolute time minute component portion 157,
absolute time second component portion 158 and in the absolute time
frame number portion 159.
In the program area 104 of FIG. 1, the time which advances in an
additive sense each time 0 comes from the start position of pause
of the first program that is the absolute time, is recorded in the
absolute time minute component portion 157, absolute time second
component portion 158 and in the absolute time frame number portion
159.
The CRC bit block 145 of FIG. 16 is a portion having 16-bit data.
In the CRC bit block 145 is recorded data for error detection of
the CRC.
The programming mode is realized by detecting the information
employing data of the Q-channel data as described above by the
subcoding detection circuit 118 of the disc reproducing apparatus
as shown in FIG. 2, decoding the information and by controlling the
accessing operation of the pickup 121 by the tracking and thread
servo circuit 121 based on the decoded signal.
Since the number of programs and the time information concerning
the individual programs are recorded in the subcode Q-channel, this
information may be displayed on a display device, such as LCD, the
serial number of the currently played program in the sequence of
the program numbers of the audio reproducing optical disc, the
elapsed play time or the absolute time from the beginning can be
checked visually.
Meanwhile, the text information, recorded in the subcode, is
necessarily digitally outputted during readout of the TOC
information. If rights are accrued in the text information, the
information may be illicitly duplicated, since there lacks means
for controlling the digital outputting of the text information,
thus raising troubles in connection with such rights.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a
disc reproducing apparatus in which at least a digital output of
the text information can be interrupted for a pre-set time.
The present invention provides a disc reproducing apparatus in
which main data, management data for managing the main data and
subsidiary data ancillary to the main data are digitally outputted
from a disc-shaped recording medium having the main data,
management data and the subsidiary data recorded thereon. The disc
reproducing apparatus includes readout means for reading out the
main data, management data and the subsidiary data from the
disc-shaped recording medium, detection means for detecting a flag
specifying inhibition of permission of digitally outputting the
subsidiary data from the subsidiary data read out by the read-out
means, and control means for inhibiting or permitting the
outputting of the subsidiary data from the digital output terminal
based on the flag detected by the detection means.
The present invention also provides a disc-shaped recording medium
including main data, management data for managing the main data and
subsidiary data ancillary to the main data, wherein an identifier
inhibiting or permitting duplication of the subsidiary data is
included in the subsidiary data.
With the disc reproducing apparatus according to the present
invention, if, when reproducing the disc-shaped recording medium
having main data and the subsidiary data recorded thereon, the
specified information, such as text data, is recorded as the
subsidiary data, and a specified flag pertinent to the specified
information, such as a copying inhibiting flag, is set in making
the recording, it becomes possible to selectively invalidate only
the subsidiary data in transmitting the main data and the
subsidiary data, such that, if rights have been accrued to the
specified information, it becomes possible to inhibit illicit
copying of the specified information.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing a conventional disc-shaped
recording medium.
FIG. 2 is a block diagram showing a conventional disc reproducing
apparatus.
FIG. 3 shows a data structure of a frame as a recording unit of the
disc-shaped recording medium shown in FIG. 1.
FIG. 4 shows a data structure of an entire subcoding frame formed
by blocking a pre-set number of frames.
FIG. 5 shows a data structure of the entire channels of the subcode
signal.
FIG. 6 shows a data structure of the Q-channels in the subcode.
FIG. 7 shows a control bit data included in the Q-channel.
FIG. 8 shows a data structure of data bits in the conventional
channel.
FIG. 9 s a block diagram showing a disc reproducing apparatus
according to the present invention.
FIG. 10 shows an illustrative arraying example of the Q-channel in
a subcode of the disc-shaped recording medium according to the
present invention.
FIG. 11A shows another illustrative arraying example of the
Q-channel in a subcode of the disc-shaped recording medium
according to the present invention.
FIG. 11B shows another illustrative arraying example of the
Q-channel in a subcode of the disc-shaped recording medium
according to the present invention.
FIG. 12A shows an illustrative arraying example in case an item of
a second management area of the disc-shaped recording medium
according to the present invention represents the size.
FIG. 12B shows a format of ID1 and ID2 when the item of the second
management area of the disc-shaped recording medium according to
the present invention represents the size.
FIG. 13 shows an illustrative example of an identifier of an ID1 of
an item of the second management area
FIG. 14A shows an illustrative arraying example in case an item of
the second management area of the disc-shaped recording medium
according to the present invention represents the album.
FIG. 14B shows a format of ID1 and ID2 and an auxiliary control
code when the item of the second management area of the disc-shaped
recording medium according to the present invention represents the
album.
FIG. 15A shows the transmission format of a digital interface.
FIG. 15B shows the channel-based transmission format of the digital
interface according to the present invention.
FIG. 16 s a flowchart for inhibiting a digital output according to
the present invention.
FIG. 17 is a flowchart for partially inhibiting duplication of a
digital output in case of recording the recording contents of an
optical disc on a magneto-optical disc.
FIG. 18 is an illustrative block diagram of a signal processing
circuit 3 of FIG. 9 according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings, preferred embodiments of the disc
reproducing apparatus according to the present invention will be
explained in detail.
The disc reproducing apparatus is such an apparatus designed for
reproducing an optical disc 1, having recorded thereon main data
and subsidiary data appended to the main data, for digitally
outputting the main and subsidiary data. The disc reproducing
apparatus includes a control circuit 4 and an interruption switch 7
responsive to a detection output of the control circuit 4 to
obstruct a digital output for transmission. The control circuit 4
is designed so that, if there is the specified information in at
least a portion of the subsidiary data, and also if there is a
specified flag pertinent to the specified information, the control
circuit can detect such flag.
Before proceeding to the description of the operation of the disc
reproducing apparatus, data recorded on the optical disc 1 of FIG.
9 is explained.
The optical disc 1 has recorded thereon a program made up of audio
data as main data, and at least one of the type of the disc-shaped
recording medium, name of a performer, name of a composer, a name
of a lyricist, name of an arranger, program title, identification
number of the disc-shaped recording medium, genre of the musical
number, publisher and the date of production, as the
above-mentioned specified information recorded in at least a
portion of the subsidiary data annexed to each program.
FIG. 10 shows an illustrative arraying example of the subcode
channel information in the lead-in area 103 which is an area
designed for writing the table-of-contents (TOC) information as the
management information for the optical disc 1.
FIGS. 11A and 11B show the format for a main portion of one block
of the subcode Q-channel in the lead-in area, that is the one
subcoding frame.
Referring to FIG. 10, the first management information 11, as the
conventional TOC information, is recorded in triplicates across
three blocks, while the second management information 12, inclusive
of letter data concerning the program, is recorded in terms of
three blocks as a unit, next to the triplicate blocks of the first
management information. That is, one block of the first management
information 11, a recorded in triplicates across three blocks, is
followed by the second management information 12 recorded across
three blocks, this recording pattern of the first management
information and the second management information being repeated
alternately.
FIG. 11A shows the format for 96 bits corresponding to the one
block of the first management information 11, that is the subcoding
frame, less the synchronization bit block 141 of FIG. 16.
In FIG. 11A, the control bit area 16 and the address area 17
correspond to the control bit block 141 and the address bit block
142 of FIG. 6, respectively, while the CRC area 18 of FIG. 11A
corresponds to the CRC bit block 145 of FIG. 6.
In FIG. 11A, areas 21 to 29 correspond to the data bit block 144 of
FIG. 16, and are equivalent to the areas 151 to 159 of FIG. 8. As
the TOC information of the lead-in area, the track number of the
area 21 is fixed at "00h", while the index area 152 of FIG. 8 is
the point area 22 and the figures of the areas 23 to 25 of the
elapsed time minute component, elapsed time second component and
the elapsed time frame component are all fixed at "00h".
Specifically, the first management information 11 in the lead-in
area specify, similarly to the conventional TOC information, the
number of programs recorded in the CD recording area, the total
recording time and the addresses corresponding to the recorded
programs. If the contents POINT of the point area 22 is "A0h" in
hexadecimal notation, the contents PMIN of the absolute time minute
area 27 specify the first program number. Similarly, if the
contents POINT of the area 22 is "A1h", the contents PMIN of the
minute component area 27 specify the last program and, if the
contents POINT of the area 22 is "A2h", the contents PMIN, PSEC and
PFRM of the areas 27 to 29 for the minute component, second
component and the frame component of the absolute time specify the
absolute time at which begins the lead-out. If the contents POINT
of the point area 22 are a 2-digit value of "00" to "99" in binary
coded decimal (BCD) representation, the contents PMIN, PSEC and
PFRM of the areas 27, 28 and 29 of the minute, second and frame
components of the absolute time denote the address at which begins
the program represented by the numerical figure in absolute time.
The address ADR of the address area 17 in the first management
information 11 in such lead-in area is "1".
FIG. 11B shows the format for 96 bits corresponding to one block of
the second management information in the lead-in area, that is the
sub-coding block, less the synchronization bit block 141 of FIG. 6.
In the second management information, the contents ADR of the
address area 17 is set to "6" and the information inclusive of the
letter data pertinent to the above program is recorded therein.
Therefore, in the lead-in area, the first management information 11
and the second management information 12 can be distinguished from
each other depending on the contents ADR of the address area
17.
In FIG. 11B, the item codes, letter codes and the serial numbers of
the contents of the letter information are recorded as the binary
code information ID1, ID2 in the areas 31 and 32, respectively. In
the next following areas 33 to 35 are recorded the binary code
information data ID3, ID4, ID5 or the text information data txt0,
txrt1 and txt2 representing letter data, depending on the items. In
the next following areas 36 to 39 are recorded text information
data txt3 to txt6, respectively.
By reading out the second management information in the lead-in
area, having alternately arrayed three blocks of the first
management information 11 and the second management information 12
recorded therein as shown in FIG. 10, the program recorded on the
recording medium, for example, letter data for an audio program,
can be read out and displayed as desired.
Since the letter information, such as the program name, is recorded
in the lead-in area, it can be read out directly after insertion of
the disc, thus conveniently reducing the waiting time for the user
and reducing the time of quality control during disc production. By
recording the letter information, such as the disc title, album
name, disc ID or the performer, the letter information can be
utilized in musical number selection for a car-laden disc changer,
a disc changer for household user or FM multiplied text
broadcast.
In a conventional usual CD, containing 14 musical numbers, as an
example, the time information is recorded nearly 700 times as the
TOC information for the inner lead-in area. This number of
repetitive recording can be halved in the present embodiment and
the redundant portion is used for recording letter data.
Thus, there is no necessity of developing new LSIs (large rescale
integrated circuits), such that the letter information can be read
out solely by changing a portion of the software program for
displaying the playback time. There is no adverse effect on the
main recording portions, such as the subcode R to W channels other
than the subcode area in the lead-in area, while future extension
possibility is also assured.
Moreover, with the conventional disc reproducing apparatus having
the text display function, the letter information of the present
embodiment can be displayed without increasing the cost.
By way of illustrative examples of the standards of the letter
information of the present embodiment, the recording contents
include the album name, performers, disc IDs, such as the disc
production number, genre specifying the sort or the field of the
program, the size of the subsidiary information specifying the size
of the subsidiary letter information and the publisher. The
recording contents may also optionally include the program name,
composers, lyricists, arrangers, date of production, other 1 and
other 2. The total number of the items of the recording contents
thus is equal to 13. The number of the letter sorts are four. The
letter sort can be managed by the country code. The number of
letters is 224 bytes at the maximum per item and may be optionally
enhanced to 672 at the maximum. The letter reading rate is 262
bytes per second. In addition, the binary code on information data
ID1 to ID5 of the areas 31 to 35 can be used for expansion, such
that reproduction control or multi-lingual reproduction is also
feasible.
The respective items of the recording contents are further
explained in detail.
FIGS. 12A and 12B illustrate one block for the case in which the
above item is "size". In these figures, areas 31 to 39 correspond
to the areas 31 to 39 of FIGS. 11A and 11B.
In FIG. 12A, an MSB 341 of the binary code information ID1 of the
area 31 is used as the last text block flag. The MSB 341 equal to
"1" represents the last block of a series of blocks of an item.
Since the item of the "size"of FIG. 12A is constituted by one block
this block is the last block, with the MSB 341 being "1". The next
following 7 bits (7-bit portion 342) are used as an item code
(contents ID) for identifying the respective items, and is set as
shown for example in FIG. 13.
That is, FIG. 13 shows the value of the contents of the 7-bit
portion 342 of the binary code information ID1 of FIG. 12A in
hexadecimal notation and the corresponding item. This item is
"size" if the contents of the 7-bit portion 342 are "00h". If the
contents of the 7-bit portion 342 are "01h to 63h", that is 1 to 99
in decimal notation, the 7-bit portion specifies the item "program"
corresponding to the program number. Similarly, the contents of the
7-bit portion "64h", 66h", 67h", 68h", 69h", 6Bh", 6Ch" and 6Dh"
denote the disc 40 ID publisher, genre code/test, date (date of
production)/country code, album name, performer, composer, lyricist
and arranger, respectively. The contents of the 7-bit portion "70h
to 7Fh" are used for expanding the number of contiguous blocks of
an item. If a block in subject is the last block of a series of
contiguous blocks in an item, the MSB 341 of the binary code
information ID1 of FIG. 12A becomes "1", so that, if x is an
arbitrary one-digit hexadecimal number (x=0h to Fh), the 8-bit
binary code information ID 1 of "6xh" and "7xh" become "Exh" and
"Fxh", respectively.
Returning to FIG. 12A, if the item is "size", the item is completed
in one block, so that the binary code information ID 1 of the area
31 is "80h". In the next area 32, an upper 3-bit portion 343 and a
lower 5-bit portion 344 are used as the letter code and as the
serial number of the contents, respectively. As for the letter
codes of 3-bit portion 343, the letter code "000", "001", "010",
"011" denote an ASII code, an European letter code inclusive of
special letters, a katakana JIS code and a shift JIS 2-byte code,
respectively. The letter code "1xx" specifies that a letter
corresponding to the country code for the item code "67h" is used.
Therefore, since the text data in one block is 7 bytes, 32 blocks
at the maximum can record letters of 224 (=7.times.32) bytes.
The next area in FIG. 12A specifies the number of items, which s
"06" that is 6, in the present case. Although the number of items
does not include the item "program", it is possible to include the
"program" item. The areas 34 to 37 specify the number of blocks
used for items "size", "album name", "performer" and "program",
respectively. In the embodiment of FIG. 12A, the areas denote "75",
"04", "03" and "62", respectively. The "size" of the area 34
denotes the number of blocks of the entire item and includes items
of "disc ID/publisher", "genre code/text", and "date/country code",
so that it is larger than the sum of the number of blocks of the
items "album name", performers and .ae butted. program".
The next two areas 38, 39 denote the state of expansion. The 8 bits
of each byte are associated with the state of expansion of the
eight items and "1" is set if the state is the expanded state. That
is, if, for items having the item codes of the 7-bit portion 342 of
the binary code information ID1 of the area 31 of "68h to 6Fh", it
is desired to record the text beyond the range of 32 blocks per
item at the maximum, represented by the serial number of the
contents of the 5-bit portion 344, expansion of further 32 blocks
becomes possible by setting the item code of the 7-bit portion 342
to "70h to 77h". For example, if it is desired to expand the name
of album of the item code of "68h" to 32 block or more, the item
code is set to "70h" as from the 33rd block and 32 blocks are
annexed contiguously for enabling 64 blocks at the maximum to be
used. If it is desired to record the text in a range exceeding 64
blocks, the item code of the 7-bit portion 342 is set to "78h to
7Fh" for enabling the text to be recorded for further 32 blocks up
to the maximum of 96 blocks. At this time, "1" is set at an
associated bit of the 8 bits of the area 39. By performing the
expansion twice in this manner, it becomes possible to record
letters of up to 96 blocks, that is 672 bytes at the maximum, since
each block is made up of 7 bytes. If both the areas 38 and 39 are
"00h", no expansion has been made.
Referring to FIGS. 14A and 14B, an recording example of the letter
information of the item "album name" is explained. The same applies
for other items of "disc ID/publisher", "genre code/text",
"date/country code", performer", "composer", "lyricist", and .ae
butted.arranger".
In the embodiment of FIG. 14A, since the item code of the 7-bit
portion 342 of the binary code information ID1 of the area 31 is
the "album name" of "68h" and is completed with one block, the last
text block flag of the MSB 341 is "1", with the 8 bits of the
binary code information ID1 being "E8h". As for the contents of the
binary code information ID2 of the area 32, the letter code of the
bit portion 343 is the ASCII code of "000", while the serial number
of the contents of the 5-bit portion 344 is "00000", as in the
embodiment of FIG. 4.
The next area 33 ff. are allocated as a principle to text letters.
In an initial block of an item, only the area 33 is a subsidiary
control area. Of the 8 bits, an MSB 345 is a copying inhibition
flag, the next following two-bit portion 346 is letter sorts and
the lower 5-bit portion 347 is ultimate serial numbers.
The copying inhibition flag of the MSB 345 of "1" and "0" denote
copying inhibition and copying permission for the text letters,
respectively. Since the flag is "1" in FIG. 14B, copying of the
text letter is inhibited.
The next following 2-bit portion 346 denotes the number of sorts of
letters used in this item. The number of sorts that is denoted by
"00" and "11" denote one sort and up to four sorts, respectively.
For different blocks, plural sorts, more precisely, up to four
sorts, of the letter codes in a string of letters are allowed. The
letter codes of each block are specified by the 3-bit portion 343
in the binary code information ID2. This renders it possible to
reduce the total number of blocks in case the Chinese characters
and alphabetical letters co-exist. The ultimate serial numbers of
the lower 5-bit portion 347 denotes the serial number of the
contents of the last block of contiguous blocks making up a string
of letters. In the present embodiment, the serial number is 0
because the item is completed in one block. The next area 34 ff. is
used for text letters. In the embodiment of FIG. 14A, the string of
letters "ABC" is stated. The area of the remaining bytes in the
block is stuffed with the so-called null-codes "00h".
As for the items of the "disc ID/publisher", "genre code/text" and
"date/country code" having the item codes of "64h", "66h .ae
butted. and "67h", it is provided that these be completed within
three blocks, that is within 21 bytes. As for the item of "genre
code/text" of "66h", the genre is prescribed in association with a
1-byte code, such that the genre codes for the genre of "05h" and
"17h" are set to, for example, classics and rock music,
respectively. If genre classification for the pre-set codes is
insufficient, 20 bytes of the letter text and "," may be appended
in continuation to the 1-byte code. As for the "date/country code"
of "67h", it is represented by four digits of the years of A.D.
(Y), 2-digit month (M), 2-digit day (D) and the country code with
roughly two letters. As for the country code, the United States,
Japan and Netherlands are denoted with US, JP and NL, pursuant to
the International Standard Organization (ISO), respectively. The
date is usually represented by the date of production. If the date
is not known, "mmdd" is entered in alphabetical letters.
Returning to FIG. 9, the operation of the disc reproducing
apparatus for reproducing the optical disc 1 is explained.
An optical pickup 2 reads out data recorded on the optical disc 1
and sends the read-out data or playback signals to a signal
processing circuit 3. The signal processing circuit 3
waveform-shapes the reproduced signals and takes out audio data and
subcoding data ancillary thereto from the playback signals and
sends the data thus taken out to a D/A converting circuit and to a
fixed terminal a of the interruption switch 7. The subcoding data
is also supplied to the control circuit 4.
The format of the digital output fed to the interruption switch 7
is now explained.
This format is pursuant to a signal format standardized as to the
digital transmission signal by the International Electrotechnical
Commission (IEC).
FIGS. 15A and 15B illustrate the signal format of the digital
interface.
In the signal format of the digital interface, each word is
comprised of 32 bits in one sub-frame.
The left and right channels are not transmitted separately but are
time-divisionally multiplexed in the order of left-right-left-right
so that each sub-frame will be transmitted beginning from the
lowermost bit. The signals are modulated in accordance with the
so-called bi-phase mark and each bit of the original signal is
represented by two bits.
Each sub-frame 200 is made up of a 4-bit synchronization preamble
portion 201 from the LSB 0 to the third bit, a 4-bit spare portion
202 from the fourth bit to the seventh bit, a 20-bit audio data
portion 203 from the 8th bit to the 27th bit, a one-bit V-bit
portion 204 of the 28th bit, a one-bit V-bit portion 205 of the
29th bit, a 1-bit C-bit portion 206 comprised of the 30th bit, and
a one-bit P-bit portion 207 comprised of the MSB.
The synchronization preamble portion 201 records synchronization
data used for locating synchronization and for discrimination of
the sub-frame 200.
The audio data portion 203 records audio data read out from the
optical disc 1.
The V-bit portion 204 is used as a flag specifying whether or not
the sub-frame data is valid, that is whether or not an error has
been made.
The V-bit portion 205 is an area used for recording the subcode
information. In the present embodiment, the LT-bit portion is used
as an area for recording the subcoding data having "6" recorded in
the address bit block.
The C-bit portion 206 is an area used for recording the channel
status, that is the properties of transmitted data, such as the
sampling frequency, whether or not emphasis has been used, and so
forth.
The P-bit portion 207 is an area in which parity bits are recorded,
and is provided for detecting the error of data being transmitted
and for perpetually maintaining the constant polarity of the
synchronization signal.
Returning to FIG. 9, the control circuit 9 has a sub-Q processor
13, an address bit processor 14 and a pulse generator 15, and
outputs processed data of the subcode Q-channel to the memory 5.
The control circuit also controls the switching operation of the
interruption switch 7.
The sub-Q processor 13 extracts data of the above-mentioned
sub-code Q-channel from the subcoding data sent from the signal
processing circuit 3 and sends the sub-code Q-channel data to the
address bit processor 14.
The address bit processor 14 processes the above-mentioned address
bit block of the sub-code Q-channel data to detect a subcoding
frame which is "6" in order to output an operation on/off control
signal to the pulse generator 15 depending on the results of
detection. The subcoding frame is referred to hereinafter simply as
text data.
That is, if there is such text data, and such text data has letter
data, it is checked whether or not "1" is set in the MSB 345 of the
subsidiary control area 33.
If "1" is set at the MSB 345, that is if the copying inhibition
flag is set, an operation-on control signal is issued. If the
copying inhibition flag is not set, an operation-off control signal
is issued.
The pulse generator 15 is responsive to the operation on/off
control signal to generate a pulse which is outputted as a
changeover signal to the interruption switch 7. This pulse has a
period and a width of 1/75 msec and 1 mm sec, respectively.
Each subcoding frame is recorded at a period of 1/75 second, as
stated above. By interrupting the digital output every 1/75 msec,
part of each subcoding frame is invalidated. Moreover, interruption
of the digital output for 1 msec each time invalidates about 10% of
the subcoding frame which is 1/75 sec or 13 msec long. If the
digital output is invalidated to this extent, the digital output
can be invalidated without the necessity of completely interrupting
the digital output.
The flowchart of FIG. 16 shows the operation of the control circuit
4 during the time of interruption of the digital output of the
above-mentioned disc reproducing apparatus.
After starting the readout of the TOC information, the sub-Q
processor 13 judges at step S1 of FIG. 16 whether or not there is
the subcoding frame having "6" written in the address bit block,
that is the text data.
If the result of decision at step S1 is NO, that is if there is no
text data, processing transfers to step S6 and, if the result of
decision at step S1 is YES, that is if there is the text data,
processing transfers to step S2.
At step S2, it is checked by the address processor 14 whether or
not a copying inhibiting flag has been set for the text data having
the letter data.
If the result of check at step S2 is NO, that is if no copying
inhibition flag has been set for pre-set data of the text data,
processing transfers to step S4. If the result of check at step S2
is YES, that is if the copying inhibition flag has been set for
pre-set data of the text data, processing transfers to step S3.
At step S3, an output-obstructing pulse of 1 msec in width and 1'75
msec in period is outputted by the pulse generator 15 for
interrupting the digital output of the text data for which the
above-mentioned copying inhibition flag has been set.
At step S4, it is checked whether or not the readout of the text
data has come to a close, that is whether or not the subcoding data
being read out is the last part of the text data.
If the result of check at step S4 is NO, that is if there is left
any text data to be read out, processing reverts to step S2. If the
result of check at step S4 is YES, that is if the text data being
read out is the last data, processing transfers to step S5.
At step S5, it is checked whether or not readout of the remaining
portion of the TOC information has come to a close, that is if the
subcoding frame being read out is the last subcoding frame.
If the result of check at step S5 is NO, that is if there is left
any TOC information to be read out, processing at step S5 is
continued. If the result of check at step S5 is YES, that is if the
last subcoding frame of the TOC information has been read out,
readout of the TOC information comes to a close.
Returning to FIG. 9, the subcode information produced by processing
by the control circuit 4 is seized and stored by the memory 5. The
subcode information is sent if necessary to a display apparatus,
not shown, or to an output terminal of the digital signal, also not
shown.
The D/A converter 6 converts the digital audio signals outputted by
the signal processing circuit 3 into address audio signals, which
are sent to an audio signal output terminal 8.
The interruption switch 7 has its fixed terminals a and b connected
to the signal processing circuit and to ground, respectively. The
interruption switch 7 operates for switching between one of these
fixed terminals and a terminal c connecting to a digital terminal
9.
The switching operation occurs based on a switching signal sent
from a pulse generator 15 in the control circuit 4. That is, in the
present embodiment, the fixed terminal b and the terminal c are
interconnected only for one second every 1/75 msec of the period
responsive to the pulse sent from the pulse generator 15.
Otherwise, the fixed terminal a and the terminal c are
interconnected at all times.
By this switching operation, the digital output sent from the
signal processing circuit 3 is interrupted and invalidated
periodically. The digital output is not interrupted completely for
relieving the load otherwise imposed on the pulse-generating PLL
circuit generating a pulse used for synchronization with the
digital signals on the reception side of the digital output sent
from the digital terminal 9.
The flowchart of FIG. 17 shows another example of the operation of
copying from an optical disc to a magneto-optical disc in the
above-mentioned disc reproducing apparatus.
After starting the operation, it is checked at step S11 whether or
not a pre-set sound-recording command that is the a command
exclusively used for commanding reproduction of the optical disc
having recorded thereon the subcode information inclusive of the
text data and concurrent recording on the magneto-optical disc has
been entered.
If the result of check at step S11 is NO, that is if the pre-set
recording command has not been entered, processing transfers to
step S20 from which processing transfers to step S0 of the
flowchart of FIG. 16 to perform the above-mentioned processing.
If the result of check at step S11 is YES, that is if the pre-set
recording command has been entered, processing transfers to step
S12.
At step S12, the TOC information is read out after waiting for the
recording waiting time for the magneto-optical disc of, for
example, approximately 1.5 sec.
At step S13, it is checked whether or not the above text data is
present in the above-mentioned sub-code Q-channel.
If the result of check at step S13 is NO, that is if there is no
text data, processing transfers to step S17. If the result of check
at step S13 is YES, that is if there is the text data, processing
transfers to step S14.
At step S14, it is checked whether or not the above-mentioned
copying inhibiting flag has been set for the text data having
letter data.
If the result of check at step S14 is NO, that is if no copying
inhibition flag has been set at a pre-set data of the text data,
processing transfers to step S16. If the result of check at step
S14 is YES, that is if the copying inhibition flag has been set at
a pre-set data of the text data, processing transfers to step
S15.
At step S15, an output obstructing pulse of the period of 1/75 msec
and a period of 1 msec as stated above is outputted for
interrupting a digital output of the text data for which the copy
inhibiting flag has been set as described above.
At step S16, it is checked whether or not readout of the text data
has come to a dose, that is whether or not the subcoding frame
being read out is the last text data.
If the result of check at step S16 is NO, that is if there is any
text data yet to be read out, processing reverts to step S14. If
the result of check at step S16 is YES, that is if the text data
being read out is the last text data, processing transfers to step
S17.
At step S17, it is checked whether or not readout of the remaining
portion of the TOC information has come to a close, that is if the
subcoding frame being read out is the last subcoding frame.
If the result of check at step S17 is NO, that is if there is left
any TOC information to be read out, processing at step S17 is
continued. If otherwise, that is if the last subcoding frame of the
TOC information has been read out, processing transfers to step
S18.
At step S18, it is checked whether or not readout of the entire
text data has come to a close.
If the result of check at step S18 is NO, that is if there is left
any text data to be read out, processing returns to step S13. If
the result of check at step S18 is YES, that is if there is no text
data to be read out, processing transfers to step S19.
At step S19, readout of the TOC information comes to a close. After
pause of about one second, reproduction of the first number of the
optical disc and concurrent recording on the magneto-optical disc
is started.
In the conventional system, when an optical disc in which a pre-set
flag, such as "6", is set in a portion of the TOC information, for
example, in the address bit block of the subcode Q-channel, and the
text data has been recorded in the subcoding frame where the
address 6 flag has been set, is reproduced, the conventional
practice has been to output the above sub-code channel
unconditionally along with other audio data for digital
transmission. With the above-described structure of the disc
reproducing apparatus, a copying inhibiting flag may be set in a
pre-set data of the subcoding frame where the above address 6 flag
is set, this flag so set may be detected and the digital output may
be invalidated responsive to the result of detection for a pre-set
time, for example, during the time of outputting the TOC
information.
For example, if rights are accrued in the above text data, and the
data recorded on the optical disc is transmitted, only the portion
of the TOC information may be selectively invalidated if the
specified flag inhibiting copying of the text data where the rights
have accrued is set. Since the audio data can be digitally
transmitted while the text data remains invalid, the text data in
which the rights have accrued can be prevented from being copied
illicitly.
In the foregoing, setting a copying inhibiting flag in a subcoding
frame of a portion of the management area of the optical disc has
been explained. Recently, researches into setting a copying
inhibiting flag in the program area is also underway.
In such case, if the interruption switch 7 is provided outside of
the signal processing circuit 3, and the digital output obtained on
processing by the signal processing circuit 3, as shown in FIG. 9,
there is a risk of interruption of audio signals recorded in the
program area.
In this consideration, an interruption switch 44 is provided within
the signal processing circuit 3 for interrupting only the subcode
information, as shown in FIG. 18.
Referring to FIG. 18, a signal read out by the optical pickup 2 is
sent via an input terminal 45 to a main signal processor 41.
The main signal processor 41 shapes the waveform of the signal sent
via an input terminal 45 for conversion into a bi-level signal. The
main signal processor 41 sends the subcode information portion to a
subcode signal processor 42, while sending the audio signal portion
to a digital output synthesis unit 43 and to an audio output
terminal 48.
The audio signal portion is sent from the audio signal output
terminal 48 to the DIA conversion circuit 6 for conversion into an
analog audio signal.
The subcode signal processor 42 extracts the subcode Q-channel data
from the subcode portion and sends the extracted signal to an
output terminal 46, while sending the subcode Q-channel data to a
fixed terminal d of the interruption switch 44.
The subcode Q-channel data is also sent from the output terminal 46
to the control circuit 4 for detecting the copying inhibition
flag.
The digital output synthesis unit 43 synthesizes the audio signal
sent from the main signal processor 41 and the data of the subcode
Q-channel sent via the interruption switch 44 to form a signal for
transmission, based on the signal format of the digital interface
shown in FIG. 15, and sends the synthesized signal as a digital
output to an output terminal 49. Meanwhile, the data of the
subcode-Q channel is handled as data of the above-mentioned U-bit
portion 205.
The interruption switch 44 switched between the fixed terminal d
and another fixed terminal e, the opposite end of which is
grounded, based on the above-mentioned switching signal, for
interconnection with the terminal f. That is, the data of the
subcode-Q channel is interrupted periodically.
As the switching signal, the above-mentioned pulse having the
period of 1/75 msec and a width of approximately 1 msec is
used.
Referring to FIG. 10, if the copying inhibiting flag is written in
an area other than the TOC information, for example, in the program
area, it becomes possible to select and invalidate only the data of
the subcode Q-channel where the copying inhibiting flag is
recorded. Therefore, if its attempted to invalidate the text data,
there is no ill effect on the audio data as the main data.
The text data having the copying inhibiting flag recorded therein
can be invalidated in the case of an optical disc in the subcoding
frame of a portion of the management area of which the copying
inhibiting flag has been recorded.
* * * * *