KR20050023354A - Recorder, recording method, reproducer, reproducing method, and recording medium - Google Patents

Abstract

The redundancy of data recorded on the CD is reduced. For example, for recording onto a CD, the bit pattern of the combined bit is determined based on the sub data. Then, the combined bits having the bit pattern determined in this way are inserted at predetermined positions of the recorded coded audio data (and subcodes). The code string thus obtained is recorded on the recording medium. As a result, the sub data can be filled with the combined bits that are not related to the data.

Description

Recording device, recording method, reproducing device, reproducing method and recording medium {Recorder, recording method, reproducer, reproducing method, and recording medium}

The present invention relates to a recording apparatus and method for recording information on a recording medium, a reproducing apparatus and method for reproducing information from a recording medium, and a recording medium.

As an optical disk-type recording medium, for example, in the case of a CD-format disk, the EFM (Eight to Fourteen Modulation) modulated data is recorded on the disk.

EFM modulation is performed by Run Length Limited (RLL) encoding, which is one of recording encoding methods. The run length limited code is prescribed | regulated so that the minimum run d and the maximum run k may become predetermined, as it is well-known. In addition, "run" means the number of consecutive "0s" between "1" and "1" in the code string by the binary value of "0" and "1". In addition, as EFM modulation, it is prescribed | regulated as minimum run d = 2 and maximum run k = 10. This corresponds to the fact that the minimum inversion interval T _min is 3T and the maximum inversion interval T _max is 11T, corresponding to the NRZI technique.

The EFM modulation is performed so as to satisfy the condition of the run length described above, and converts a single 8-bit signal into an EFM word of 14 channel bits. However, when connecting each EFM word, the run length condition may not be satisfied by the combination of the bit patterns of the EFM words in the front-rear relation. Therefore, in order to satisfy the condition of run length normally, a coupling bit is inserted between every 14 channel bit EFM words.

In the case of CD format, the combination bit is 3 bits, so as a bit pattern, in accordance with the rules of run length,

000

100

101

Four patterns of 001 can be used. Among these patterns, a pattern capable of satisfying the condition of the run length is usually selected and inserted as a combination bit.

In addition, since the combination bit is 3 bits, it can be said that the degree of freedom in which a bit pattern to be inserted between EFM words can be arbitrarily selected from a plurality of patterns is provided.

Therefore, by using this, as the bit pattern of the combined bit, after the above run length condition is satisfied, the DSV (Digital Sum Value) is selected to be as close to zero as possible. In other words, the combined bit is used for DSV control.

DSV is a value indicating the direct current balance of the digital signal in unit time, and is represented by an integral value when bit 1 is set to +1 and bit 0 is set to -1.

For example, as the recording encoding process, it is known that direct current noise is generated by, for example, garbage or scratches attached to the recording medium during data signal reading. Therefore, if the digital signal recorded on the recording medium does not contain a direct current component, it is also possible to remove the direct current noise component later with a filter, so that the direct current component is preferably zero. This DC component generation is judged based on the DSV value. When the value of DSV converges to 0, no DC component is generated. On the contrary, a DC component is generated.

In addition, when performing the Non Return to Zero Inverted (NRZI) modulation on the EFM coded code string into which the combining bits are inserted as described above, inversion / non-inversion of the code string is controlled by the inserted combining bits. do. As a result, the DSV value of the EFM modulated code string is controlled to be as low as possible.

The combined bits are used only to satisfy conditions such as run length, DSV, and the like of the data encoded as described above. In view of the fact that the data is recorded on the recording medium by digital signals, the combined bits can be said to be redundant, which is not used as data in the digital signals recorded on the CD.

As is well known, in the CD format, recording is performed in frame units of 588 channel bits. One frame consists of a Sync code of 24 channel bits, an EFM word (14 channel bits) of 33 symbols (including subcoding for one symbol), and 34 combined bits arranged before and after each EFM word. Therefore, the total capacity of the combined bits in one frame is 3x34 = 102 channel bits, and the number of bits occupying about 17% in the frame is not used as data.

1 is an explanatory diagram showing a frame structure of a signal recorded on a CD.

2A, 2B, 2C, 2D and 2E are explanatory diagrams showing the format of a signal recorded on a CD by the state of a reproduction signal.

3 is an explanatory diagram showing a bit pattern of combined bits.

4 is an explanatory diagram showing a structure of a subcoding frame.

5 is an explanatory diagram showing a code string of a sync code and a sub code sync and the combined bits inserted therebetween.

6 is an explanatory diagram showing a bit pattern of a sync code and a sub code sync and the combined bits inserted therebetween.

7 is an explanatory diagram showing an encoded string of combined bit correspondence data in this embodiment.

8 is an explanatory diagram showing another example of the encoding of the combined bit correspondence data in this embodiment.

9 is a block diagram showing the configuration of a recording system according to the present embodiment.

10 is a block diagram showing the configuration of a playback system according to the present embodiment.

Accordingly, the present invention has been made in view of the above-described problems, and an object of the present invention is to enable at least a part of the combined bits to be inserted into the recorded coded main data to be effectively used as data.

Therefore, the bit pattern of the combined bit to be inserted into the predetermined position of the main data encoded by the predetermined recording encoding method is determined. Based on the sub data to be recorded on the recording medium together with the main data, Bit pattern determination means capable of determining the bit pattern, combined bit insertion means for inserting the combined bits of the bit pattern determined by the bit pattern determination means into predetermined positions of the encoded main data, and inserting the combined bits into the main data, It is assumed that a recording apparatus is constituted by recording means for recording the formed information on a recording medium.

In addition, as a recording method, a bit pattern of a combined bit to be inserted into a predetermined position of the main data encoded by a predetermined recording encoding method is determined, and based on the sub data to be recorded on the recording medium together with the main data. Bit pattern determination means capable of determining the bit pattern of the combined bit, a combined bit insertion order for inserting the combined bit of the bit pattern determined by the bit pattern determination procedure into a predetermined position of the encoded main data, and the main data. The recording order of recording the information formed by inserting the coupling bits into the recording medium is performed.

According to each of the above configurations, after determining the bit pattern of the combined bit in accordance with the sub data, the combined bit is inserted into a predetermined position in the recorded encoded main data. This makes it possible to match the bit pattern of the combined bit recorded on the recording medium with the data value of the sub data.

Reading means for extracting and reading out the combined bits from at least a recording medium on which the main data encoded by the predetermined recording encoding method and the combined bits inserted into the predetermined positions of the main data are recorded; It is assumed that a reproducing apparatus is provided having data value obtaining means for obtaining a data value as sub data by using the bit pattern of the combined bit read out by the means.

Further, as a reproduction method, at least, the combined bits can be extracted and read out from a recording medium on which the main data encoded by the predetermined recording encoding method and the information consisting of the combined bits inserted into the predetermined positions of the main data are recorded. The reading order and the bit pattern of the combined bits read out according to the reading order are used to execute a data value acquisition procedure for obtaining a data value as sub data.

According to each of the above configurations, the data value is obtained using the bit pattern of the combined bit read out from the recording medium. In other words, it is possible to obtain a value as meaningful sub data from the bit pattern of the combined bit.

In addition, as a recording medium, the information which consists of the main data encoded by the predetermined | prescribed recording encoding method, and the combined bit inserted in the predetermined position of this main data is recorded, and a combined bit according to the data value as sub data is recorded. It is configured to be recorded with a bit pattern.

In the above configuration, the bit pattern of the combined bit recorded on the recording medium represents the data value as the sub data. In other words, a recording medium using the combined bit area together with the recorded coded main data and recording the sub data is obtained.

1. Signal Format of CD

2. Combination bit correspondence data

 2-1. Consideration of Insertion Location of Data for Combined Bits

 2-2. Encode Example

3. System Configuration

 3-1. Record system

 3-2. Playback system

1. Signal Format of CD

In this embodiment, the case where the recording medium is a CD (Compact Disc) is taken as an example. First, the format of the signal recorded on the CD will be described.

Fig. 1 shows the structure of one frame as a signal recorded on a CD. The digital signal is recorded on the CD by the sequence of frames shown in this figure.

As shown in this figure, one frame is formed of 588 channel bits.

It consists of a 24-channel bit Sync code, 32 symbols (32) EFM words (14 channel bits), and 34 combined bits (3 bits) arranged before and after each EFM word.

The Sync code is a code for frame synchronization.

This Sync code is formed by a bit pattern which becomes an inversion interval of 11T + 11T + 2T as shown below in FIG. In other words, the maximum inversion interval T _max = 11T specified in the EFM modulation is continuous twice, and a pattern in which 2T other than the rule is added is added.

An EFM word is a signal unit obtained by converting an 8-bit symbol into 14 bits by EFM modulation.

In EFM modulation, the run length rule is the maximum inversion interval T _max = 11T to the minimum inversion interval T _min = 3T. According to this rule, if a bit pattern of 14 bit length is made, 267 patterns can be obtained as well known. As the EFM modulation, 256 patterns are used and assigned to 8-bit data of one symbol.

The combined bits of 3 bits are inserted for the purpose of ensuring that the EFM-encoded signal does not violate the run length rule and to perform DSV control.

In other words, when the EFM words are simply connected, the combination of bit patterns of the EFM words in the context may violate the run length rule. Thus, for example, in the case of CD, as the coupling bit, a bit pattern that satisfies a run length condition of maximum inversion interval T _max = 11T and minimum inversion interval T _min = 3T is selected. At the same time, the bit pattern of the combined bit is selected such that the value as the DSV converges to 0 as much as possible.

In this way, when performing Non Return to Zero Inverted (NRZI) modulation on the code string of the EFM word in which the combined bits are inserted, inversion / non-inversion of the code string is controlled by the bit when inserted. As a result, control is performed so that the DV value of the EFM-modulated code string is as zero as possible. That is, DSV control is performed.

For example, as an EFM word in a frame, first, the first EFM word has contents as a sub code.

Subsequently, the main data is recorded by the 12th EFM words from the 2nd to the 13th, followed by the 4th through the 14th to 17th EFM words. Parity with respect to the main data by 12 EFM words is recorded.

In the same way, the main data is recorded by the 12th EFM words from the 18th to 29th, followed by the 4th EFM words from the 30th to 33rd, and by the 18th to 29th EFM words. Parity with respect to the main data is recorded.

2 shows an example in the case where a signal recorded in the above-described signal format is read out from the CD.

The signal read out from the CD is obtained as an RF signal, for example, as shown in Fig. 2A.

This RF signal is run-length modulated on the basis of one cycle of the channel clock shown in FIG. 2B, and is obtained as a non-return to zero inverted (NRZ) modulated code string as shown in FIG. 2C.

When the NRZ code sequence shown in Fig. 2C is viewed as an NRZI modulated signal, as shown in Fig. 2D, each inversion interval is a maximum inversion interval T _max = 11T to a minimum inversion interval T _min = 3T. You can see that it stays within the range. In other words, the condition of run length in EFM modulation is satisfied.

Incidentally, as a correspondence with the frame structure of the reproduction signal shown in Fig. 2, it is shown in Fig. 2E.

That is, it is divided into the first 11T + 11T + 2T section shown in FIG. 2D and the following section of 3T. The signal in the section of 11T + 11T + 2T forms the bit pattern of the Sync code, and the signal in the remaining 3T section forms the combined bit. Here, when the bit pattern of the Sync code is represented by the NRZI technique, as shown in Fig. 2C,

Sync code = 100000000001000000000010

It becomes

Subsequently, in FIG. 2D, a signal in a section of 14T consisting of 7T? 3T? 4T forms a bit pattern of one EFM word. In addition, since the EFM word at this position is the first EFM word following the Sync code, data as a sub code is stored as shown in FIG.

In addition, a combination bit is formed by the signal of the first 3T section in the 7T section, and the remaining 10T portion of the next 4T section and the next 11T section is formed by the signal of the first 3T section. The bit pattern of the next EFM word is formed by the signal of the total 11T section formed from the section.

3 shows a bit pattern of the combined bits inserted before and after the EFM word as described above.

Since the combined bit is three bits, simply according to the NRZ technique,

000

001

101

011

100

101

110

8 patterns of 111 are obtained. However, according to the run length rule in the EFM modulation, since the minimum inversion interval T _min = 9T, at least two '0's must be contiguous between the bit values'1' and '1'. Therefore, as the combined bit, a bit pattern in which '1' is continuous and a bit pattern in which only one '0' exists between '1' and '1' cannot be used.

As a result, of the eight patterns,

011

101

110

The bit pattern of 111 is excluded. As a result, as shown in FIG. 3,

000

100

010

Four patterns of 001 can be used as combined bits. In other words, as the combined bit, the randomness of the selection is given among these four patterns.

4 shows a format of a sub code formed by an EFM word located immediately after the Sync code of each frame.

The frame first has the structure shown in FIG. At the time of reproduction, for example, an EFM word of a sub code is extracted from 98 consecutive frames. Then, after EFM demodulation of each EFM word as a sub code into an 8-bit symbol, one sub-coding frame shown in Fig. 4 is formed by collecting the symbols of the sub codes for these 98 frames.

In 98 frames forming one sub-coding frame, the sub code data of the first and second frames at the beginning is a synchronization pattern for sub code extraction. Here, this sync pattern will be referred to as a sub code sync.

The subcode sync of the first frame is referred to as S0, and the subcode sync of the second frame is referred to as S1.

As described above, the EFM transformation uses 256 patterns among the 267 patterns according to the run length rule. Therefore, as shown by 267-255 = 11, 11 patterns are prescribed | regulated as not using.

However, for these subcode sinks S0 and S1, as is well known, as the bit pattern of the EFM word, two specific patterns out of the 11 patterns other than the above-described regulations are used and are used for this pattern. .

The bit pattern described by NRZ for each of the subcode sinks S0 and S1 is shown in Fig. 4, but is as follows.

S0 = 00100000000001

S1 = 00000000010010

In FIG. 4, channel data of 96 bits is formed by 96 frames from the remaining third frame to the 98th frame. That is, P-channel data, Q-channel data (Q1-Q96), R-channel data (R1-R96), T-channel data (T1-T96), U-channel data (U1-U96), and V-channel data (consisting of P1-P96) Subcode data of V1 to V96 and W channel data W1 to W96 are formed.

As is well known, the P channel and the Q channel are used for management of access and the like. However, the P channel only shows the pause portion between the track and the track, and more detailed control is performed by the Q channels Q1 to Q96. The data of the R channel to the W channel are provided to form text data, for example.

2. Data for combining bit

 2-1. Consideration of Insertion Location of Data for Combined Bits

First, as understood from the description of Figs. 1 and 2, the coupling bit in the CD format is a signal that satisfies the condition of run length and is used for DSV control.

Although the bit pattern of the combined bit has been described with reference to FIG. 3 as four patterns exist, as described above, the bit pattern of the combined bit may be arbitrarily selected as long as it satisfies the run length rule and the DSV control. It becomes.

Thus, on the premise that the bit pattern of the combined bit is arbitrarily selected in this manner, it can be said that it is possible to associate a value of data having a meaning with a bit pattern of the arbitrarily selected combined bit. That is, in selecting the bit pattern of the combined bit, it is good to determine the bit pattern according to the data value, insert the combined bit of the determined bit pattern into the code string, and perform recording.

In this way, the bit pattern of the combined bit has a meaning as a data value. In other words, data can be filled in the area of the combined bit. That is, in addition to the main data recorded as the EFM word, it is possible to record the sub data in the area of the combined bit.

In addition, since main data here is data recorded as an EFM word, it becomes digital audio data in case of CD. In this case, the subcode data obtained as the subcoding frame (Fig. 4) can also be considered as being included in the main data.

Hereinafter, description will be made on the sub data as the present embodiment recorded using the combined bits. In addition, in this specification, the sub data recorded using the combined bit shall be referred to as "combined bit correspondence data".

First, the position of the combined bit into which the combined bit corresponding data is to be inserted will be described.

First, the bit pattern of the combined bit is described as being arbitrarily selective. However, the bit pattern of the EFM word changes depending on the contents of the actual audio data. The combination of the bit patterns of the two EFM frames described above may cause the case where only one bit pattern can be selected as long as the condition of the run length is satisfied. That is, it is considered as a possibility that the arbitrary selectivity with respect to the bit pattern of the combined bit may be lost.

Therefore, for example, in the case where data is recorded by the combination bit, it is reasonable to use the combination bit at the insertion position where the arbitrary selectivity is assuredly at least as possible as possible.

Therefore, in the CD format described so far, the insertion position of the bits will be considered when the arbitrary selectivity of the combined bits is reliably obtained.

Here, in the frame structure shown in FIG. 1, the Sync code has the bit pattern shown in FIG. 2C in the NRZ technique. That is, in the NRZI technique, an inversion interval of 11T + 11T + 2T is obtained. This bit pattern is the same for each frame. That is, this Sync code can be said to be normally constant without depending on the contents of the main data.

In the frame, the subcode is stored in the first EFM word following the Sync code as described in FIG. Here, when data of P channel to W channel as a sub code is stored, the pattern of the EFM word changes in accordance with the data contents.

However, when the subcodes stored in the EFM word are the subcode sinks S0 and S1, as described in Fig. 4, the subcodes S0 and S1 are also constant for each subcode sink S0 and S1, and furthermore, the EFM modulation is performed. Bit patterns other than those specified in the above are used. Therefore, the EFM word that stores the sub code sinks S0 and S1 is usually referred to as a constant bit pattern.

Here, in Fig. 5, the state of the code string of the part including the Sync code and the sub code sync in the frame in which the sub code sync SO or S1 is stored in the EFM word as the sub code is shown by the NRZ technique.

As shown in this figure, first, the Sync code and the EFM word as the sub code sync SO are inserted with three bits of combined bits [xxx] interposed therebetween to form a code string.

Similarly, the code string is also formed by inserting and connecting the 3-bit combining bit [yyy] between the Sync code and the EFM word as the sub code sync S1.

As the coupling bit, four patterns exist as shown in FIG. After that, in the case of the bit pattern of the code string by [Sync code combining bit (xxx)-subcode sync (S0)) of the two code strings shown in FIG. 5, the condition of the run length of the EFM modulation is satisfied. As a bit to say, as shown in FIG.

Pattern A: 000

Pattern B: 010

Pattern C: 001

3 patterns can be selected and used.

In addition, in the case of the bit pattern of the code string by [Sync code-combined bit (yyy)-sub code sync (S1)], as shown in Fig. 6, the combination that satisfies the condition of the run length of the EFM modulation is also shown. As a bit,

Pattern D: 010

Pattern E: 001

2 patterns can be selected and used.

In this way, it can be said that the arbitrarily selectivity of three patterns is given to the combined bit xxx forming the code string formed by the [Sync code combined bit (xxx) -sub code sync (S0)]. .

Further, for the combined bit yyy forming the code string formed by [Sync code-combined bit yyy-sub code sync S1], three patterns of arbitrary selectivity are provided. As for any code string, the combination of the sync code and the bit pattern of the sub code sync SO or S1 does not change, and it can be said that the arbitrary selectivity shown in Fig. 6 is usually obtained.

Thus, in the present embodiment, in this manner, the combining bit xxx forming the code string by [Sync code combining bit (xxx)-sub code sync S0) and the [Sync code combining bit (yyy) ? -Subcode sink S1] is given meaning by a predetermined rule to the combined bits yyy forming the code string, and stores data values as sub data for encoding.

In the case shown in Fig. 6, since 3 patterns are provided to the combining bit xxx of the subcode sink S0, and 2 patterns are provided to the combining bit yyy of the subcode sink S1, so that 3x2 = It is possible to record data having a significance of about 6 in every 98 frames.

In addition, as described above, the coupling bit should be selected so as to satisfy not only the run length condition but also the DSV control condition. Therefore, as described above, only when the combining bit xxx of the subcode sink S0 and the combining bit yyy of the subcode sink S1 are provided with arbitrary selectivity based on the condition of run length. There is a possibility that the DSV value becomes unbalanced.

However, since the combining bit xxx of the sub code sync S0 and the combining bit yyy of the sub code sync S1 appear only once every 98 frames, unbalanced DSV values are problematic. It can be suppressed to the extent that it is not. In addition, if it is also possible to cancel the unbalance by the bit in other cases, since it is considered to be sufficient, there is no problem in particular.

 2-2, Encode Example

As described above, as the format of the combined bit correspondence data of this embodiment, the combined bit xxx inserted immediately before the EFM word as the sub code sink S0 and the immediately inserted EFM word as the sub code sink S1 are inserted. The combined bits yyy are filled with data as combined bit correspondence data (sub-data).

Therefore, since the combined bit correspondence data is filled in the combined bit, the encoding example will be described first with reference to FIG.

In FIG. 7, a data unit as one combined bit corresponding data is formed by five subcoding frames.

In this case, since the data unit as one combined bit correspondence data is formed by five subcoding frames, S0 [0] to S0 [4 for the subcode syncs S0 and S1 stored in each subcoding frame. ] And S1 [0] -S1 [4].

In addition, the 1-byte data to which the combined bit correspondence data should be filled is set to K here, and each bit which forms this 1-byte data is K [7]-K [0] through the LSB on the MSB side, respectively. It is described as.

In addition, the patterns A-E described in the following description refer to the combining bit pattern demonstrated by FIG.

As shown in FIG. 7, first, the pattern A is selected for the combining bit corresponding to the subcode sync SO [0]. This pattern A is specified to be a synchronization signal Sync added to each data unit with respect to the combined bit correspondence data.

As can be seen from FIG. 3, the pattern A is a pattern in which the inversion of the signal does not occur only among the bit patterns as the combined bits. Therefore, by looking at the polarity of the Sync code pattern and the sub code sync, it is possible to more accurately distinguish the patterns B and C which are patterns of other S0 corresponding coupling bits. That is, in the case of the sub code sync S0, if the last bit of the Sync code and the first bit of the sub code sync exist in the same polarity in the case of the sub code sync S0, the combined bit is present. You can see that it is A.

By using the synchronization signal as the pattern A as a trigger, it becomes possible to more accurately obtain the order of the data strings corresponding to each subcode sink described below.

In addition, the coupling bit corresponding to the sub code sync S1 [0] is supposed to function as the parity P. In this case, therefore, any of the patterns D and E is selected as the value of the parity P to be stored. Here, the patterns D and E are defined as corresponding to (0, 1) as data values, that is, by selecting one of the patterns D and E, the parity bit P is selected as (0, 1). Any value of 1) will be selected.

Then, the remaining subcode sinks (S0) [1]-(S1) [1], (S0) [2]-(S1) [2]-(S0) [3]-(S1) [3], (S0 Each of the combined bits corresponding to [4]-(S1) [4] indicates the value of bits K [7] to K [0], and the data contents of one byte are represented.

Here, in response to the subcode sync SO, the patterns B and C are defined as corresponding to (0, 1) as values taken by one bit as shown in the figure.

So, for example, if the bit value takes '1' as the bit K [7] (MSB), the pattern C is selected as the combining bit corresponding to the subcog sink S0 [1]. It becomes.

In addition, as described above, the patterns D and E are defined as corresponding to the bit values 0 and 1, corresponding to the subcode sink S1, so that following the MSB If bit K [6] which is the lower bit takes '0', pattern D is selected.

Subcode sync (S0) [2], S1 [2], (S0) [3], S1 [3], (S0) [4] corresponding to the following lower bits (K) [5]-[0] The same applies to S1 [4]. That is, although the bit K corresponds to the bits [5] to [0], a combination bit corresponding to the subcode sync SO is selected according to the value to be taken. In the combination bit corresponding to the subcode sink S1, one of the patterns D and E is selected.

In such an encoding method, 15 (= 75/5) bytes of data can be filled in, for example, for one second (= 75 sub-coding frames).

Subsequently, with reference to FIG. 8, another example of the encoding for filling the combined bit correspondence data (sub-data) will be described.

In this case, one data unit corresponding to nine sub-coding frames to be connected is formed as combined bit corresponding data. Here, the subcode sinks S0 and S1 stored in these nine subcoding frames are referred to as S0 [0] to S0 [8] and S1 [0] to S1 [8].

Also in this case, the pattern A is selected as the coupling bit corresponding to the sub code sync SO [0] to function as a synchronization signal Sync. In addition, any of the patterns D and E (0, 1) is selected as the parity bit P as the combining bit corresponding to the sub code sync S1 [0].

Even in this case, the data length filled with the combined bit correspondence data (sub-data) for this data unit is one byte (8 bits). In this case, however, in order to provide correction capability for data, inverting bits are provided corresponding to each of the bits K [7] to K [0]. These inversion bits are shown as inversion bits K: inv [7] to K: inv [0], respectively.

In this case, bits K [7] to K [0] are assigned to subcode sinks S0 [1] [2] [3] [4] [5] [6] [7] [8], respectively. Each corresponding combination bit is adapted to correspond. Inverted bits K: inv [7] to K [0] correspond to subcode sinks S1 [1] [2] [3] [4] [5] [6] [7] [8], respectively. Each combination bit is made to correspond. That is, a group of two bit bits and a group of inverted bits corresponding to the bit value are obtained by the group of two combined bits corresponding to the sub code sinks S0 and S1 stored in the same subcoding frame.

Then, for each of the combination bits corresponding to the subcode sink S0 [1] [2] [3] [4] [5] [6] [7] [8], bits K [7] to Some of the patterns B and C are selected according to the values K [0] should each actually take.

In addition, the bits K [7] to K [0 are assigned to respective combined bits corresponding to the subcode sinks S1 [1] [2] [3] [4] [5] [6] [7] [8]. According to the value to be taken by the inversion bits K: inv [7] to K [0] obtained by inverting the value of].

With this encoding, bits K [7] to K [0] and inverted bits K: inv [7] to K [0], respectively, from the data on the subcode sink S0 and the data on the S1 side, respectively. By this, two bytes of data in which the bit values of each other are inverted are obtained, and the parity bit P can be obtained.

Thus, for example, it is possible to determine whether or not there is an error with respect to the bit K based on the data sequence of the bit K and the parity P. When it is determined that there is an error, an exclusive logical sum is applied to each data string of the bit K and the inverted bits K: inv, thereby making it possible to identify and correct the error location.

In addition, as a data encoding example here, in order to make description easy to understand, only a simple example is shown to fill in 1 byte of data. In order to improve the reliability of data, it is easy to perform more complex data encoding, for example, by using an appropriate method according to the purpose of writing data, such as spreading data using scramble or interleaving, repetitive recording of the same data, and the like. It is possible to.

3. System Configuration

 3-1. Record system

Subsequently, the recording system of the present embodiment for encoding the combined bit correspondence data as sub data and recording it on the CD will be described with reference to FIG. In this figure, a signal processing process is shown as a block.

As shown in this figure, for example, main data, which is digital audio data, is moved to the C2 encoding process 2 after the scramble process is performed by the scramble process 1 according to a predetermined rule.

As the C2 encoding process 2, a process for adding C2 parity is executed as an error correcting code based on the CIRC (Cross Inter Leaved Reed-Solomon Code) method. Then, interleaving is performed on data to which C2 parity has been added by the following interleave processing (3). Then, C1 parity, which is another error correcting code based on the CIRC method, is added to the interleaved data by the C1 encoding process (4).

After odd delay is performed by the odd delay process 5, data to which C1 parity is added is inverted with respect to the parity value by the next parity inversion inversion process 6. Then, EFM modulation is performed on the data that has undergone the parity inversion processing 6 by the EFM modulation processing 7. As a result, for example, a 14-channel bit EFM word forming a frame shown in FIG. 1 is obtained. The EFM word obtained by the EFM modulation process 7 also includes an EFM word as the first subcode in the frame. Therefore, the EFM words as the word sinks S0 and S1 are also obtained as EFM-modulated EFM words at intervals corresponding to every 98 frames.

In this way, the EFM word obtained by the EFM modulation process 7 is passed to the synthesis process 11.

On the other hand, the combined bit correspondence data (sub-data) to be filled in and recorded in the combined bits is encoded by the combined bit correspondence data encoding process (8). That is, for example, as described with reference to FIG. 7, the bit pattern of the combined bit located immediately before the subcode syncs S0 and S1 corresponding to the data value of the synchronization signal and the parity insertion and combined bit correspondence data. The process for determining In the case of corresponding to the encoding shown in Fig. 8, the bit pattern of the combined bit corresponding to the inverted bit is also determined.

In the combined bit generation process 9, as a general rule, a bit pattern of a combined bit that satisfies the run length rule and the conditions of the DSV control while referring to the bit pattern of the EFM word obtained by the EFM modulation process 7 is generated. Let's do it.

However, for the combined bits immediately before the subcode sinks S0 and S1, a bit pattern is generated in accordance with the bit pattern of the combined bits determined by the combined bit correspondence data encoding process 8 as described above.

Then, the combined bits of the bit pattern generated in this manner are passed to the synthesis process 11.

In addition, the sync code pattern generation processing 10 first generates a bit pattern as a Sync code having an inversion interval of 11T + 11T + 2T as described with reference to Figs. 11).

As the synthesis process 11, for example, the EFM words obtained by the EFM modulation process 7 are arranged with the Sync code generated by the Sync code pattern generation process 10 at the head. That is, the code string of the EFM word headed by the Sync code is obtained. Then, the combined bits of the appropriate bit pattern generated by the combined bit generation process 9 are inserted before and after the EFM word in the code string thus obtained. As a result, the recording signal having the frame structure shown in FIG. 1 is obtained. The recording signal according to the sequence of the frame is recorded on the CD.

As the CD on which the recording signal processed as described above is recorded, not only the original audio data (including sub code data) which is main data, but also sub data other than this are recorded in the combined bit area. do.

 3-2. Playback system

Subsequently, a configuration of a reproducing system for reproducing in response to the CD of the present embodiment in which sub data is recorded in the combined bit area will be described with reference to FIG. Also in this figure, each reproduction signal process is indicated by a block.

The signal read out from the disk as the CD detects the Sync code pattern by the synchronous detection process 21. In addition, as is well known, so-called sink protection processing such as window protection, insertion processing, and front / rear protection is actually performed.

By the synchronization detecting process 21, the frame synchronization can be performed and subsequent processing can be executed. Then, signal processing as the EFM demodulation process 22 is performed for each frame unit. As a result, the EFM word of 14 channel bits is modulated so as to be returned to the signal of one symbol in 8 bits. In the even delay process 23, the parity inversion process 24, the C1 decode process 25, the deinterleave process 26, the C2 decode 27, and the descramble process 28, operations inversely to those of the above-described recording process are performed. The main data is read out, and the same processing as in the prior art is performed.

In the case of this embodiment, the signal in units of frames obtained by the synchronous detection process 21 is also passed to the sub code sync detection process 29. FIG. Here, the sub code syncs S0 and S1 are detected from the input signal. When the sub code sinks S0 and S1 are detected, the detection timing is notified to the combined bit correspondence data decoding process 30.

As the combined bit correspondence data decoding process 30, for example, the sub code in the signal of the frame after the synchronous detection is based on the notification of the sub code sync S0 and S1 detected from the sub code sync detection process 29. The positions of the sinks S0 and S1 are specified, and the combined bits inserted immediately before the subcode sinks S0 and S1 are identified. When extracted, the decoding process is performed on the combined bits.

The combined bits extracted in this step can identify which of the subcode sinks S0 and S1 has been inserted. Then, the combined bit correspondence data decoding processing 30 performs the following processing, for example, based on the correspondence with the subcode sinks SO and S1 and the bit pattern of the extracted combined bit.

For example, if it is assumed that the sub data to be reproduced is data encoded by the method shown in Fig. 7, first, the pattern A is used as a bit pattern of the combined bits corresponding to the sub code sync SO [0]. ) Is detected. That is, the synchronization signal is detected to synchronize the data unit as the combined bit corresponding data.

Subsequently, if this synchronization signal is detected, the next sub code sync S1 [0] is detected by the sub code sync detection process 29, and the effect thereof is notified. In the combined bit correspondence data decoding process 30, therefore, the bit value as the parity bit P is obtained by determining which of the patterns D and E is the combined bit corresponding to the subcode sink S1.

Subsequently, by the subcode sync detection process 29, the subcode sync S0 [1] → S1 [1] → S0 [2] → S1 [2] → S0 [3] → S1 [3 ] Is detected from S0 [4] → S1 [4]. Therefore, whenever the combined bit correspondence data decode processing 30 is notified that the respective subcode sinks S0 and S1 have been detected, the bit pattern of the combined bit extracted in correspondence with this is the pattern (B, C) or the pattern. One of (D, E) is determined, and the values of each bit K [7] (MSB) to K [0] (LSB) are obtained.

By such a process, for example, one-byte combined bit correspondence data (sub-data) is obtained. By repeating this process, the following combined bit correspondence data can be obtained by one byte.

Here, the recording and reproducing apparatuses corresponding to the recording and reproducing systems shown in Figs. 9 and 10 may be configured such that the respective processes described with reference to Figs.

For example, as the recording apparatus, a circuit for generating a bit pattern of the combined bits in correspondence with the combined bit corresponding data (sub-data) may be added as an encoding function. In addition, the reproducing apparatus may add a decode function so as to extract the combined bits, analyze the bit patterns of the extracted combined bits, and substitute the data values as the combined bit corresponding data.

That is, for example, there is no need for physical processing such as wobble (meander) of the track and phase modulation of the pit formed on the disk. For example, only a design change that adds a circuit having a simple configuration to the LSI mounted in the actual recording device and the reproduction device may be performed. Therefore, in addition of the function as this embodiment, the fall of manufacturing efficiency, such as a design, and a cost amplifier are suppressed.

By the way, as an actual use for the combined bit correspondence data (sub-data) recorded and reproduced in this way, for example, it is considered to be applied to an encryption system such as scramble and masking. In this case, for example, the main data is encrypted to perform a process from the scramble process 1 to the EFM modulation process 7 shown in Fig. 9 to generate a recording signal.

Thereafter, as the combined bit correspondence data (sub data), an encryption key used when the main data is encrypted is used, and the data of the encrypted key is recorded in the combined bit. On the reproduction side, the encryption key, which is data filled in the combined bits, is reproduced and decoded. As a result, the system configuration can be obtained by reproducing the encryption key, decrypting the encryption key, and reproducing and outputting the main data normally only by the reproducing device having a decoding function for the encryption key. have.

Also, for copyright protection, recording of copy prohibition / permission information or the like as combined bit correspondence data (sub-data) is also considered.

In addition, if a system capable of recording sub data can be constructed corresponding to recordable media such as CD-R / RW, for example, recording of information as combined bit-corresponding data so as to be able to identify the type of the disc created. do. This makes it possible to make the efficiency of the follow-up of the illegal radiation higher.

In this way, the use of the combined bit correspondence data according to the present embodiment is considered in various ways, and it should not be particularly limited.

In the above embodiment, the CD system is taken as an example. For example, a signal having a format in which a combined bit is inserted so as to be represented by an MD (mini-disc) system or the like corresponding to a magneto-optical disk and recording and reproducing compressed audio data. The present invention can be applied to the overall system in which is recorded and reproduced. Therefore, the present invention can be applied to a case where the recording medium is other than the disk media, for example, having a tape-type recording medium or a memory element.

In addition, in the case of filling as a bday, the insertion position of the bit is not limited between the sync code (frame synchronization signal) and the sub code sync as in the embodiment.

That is, in the embodiment, as a representative example in which the bit pattern of the signal unit before and after the combined bit is fixed, the butcher is filled between the Sync code (frame synchronization signal) and the sub code sync.

Therefore, the position to be filled in the sub-data in the present invention may be any insertion position where the arbitrary selectivity can be reliably obtained with respect to the bit pattern of the combined bit, for example, in accordance with the bit pattern of the signal unit before and after the combined bit.

As described above, in the present invention, after determining the bit pattern of the combined bits based on the sub data, the combined bits are inserted at predetermined positions of the recorded coded main data. The information thus obtained is recorded on the recording medium.

That is, according to the present invention, the function as data is given by selecting the bit pattern for the combined bit. In other words, the sub-data is filled with the combined bits for recording.

This makes it possible to use the combined bit area which has not been meaningful as data so far as the data area, so that the redundancy of the data is lowered by that much, and the recording capacity of the recording medium can be effectively used.

In addition, since data is recorded with respect to the combination bit which was not originally related, the original main data is not affected in recording the sub data. Therefore, for example, even if it is desired to record any additional information on the package media that already exists, no further processing is performed on the contents already recorded as the main data, and then the additional information is recorded by recording the sub data. Can record That is, for example, it is also possible to easily provide extensibility to the existing package media.

In the present invention, the information is read from the recording medium on which the sub data as the combined bit is recorded together with the main data as described above, the combined bit is extracted, and the data value as the sub data is obtained by using the bit pattern of the extracted combined bit. To get That is, the sub data recorded by combining bits is decoded and obtained.

In this way, the sub data recorded as the combined bits can be reproduced, and depending on the method of applying the sub data, for example, it is possible to add a function such as copyright protection or encryption, and provide a system with higher added value than ever before. Can be.

In this way, as described above, as the recording medium on which the sub data is recorded as the combined bits, the contents are effectively used.

In addition, since data is recorded using the existing combination bits, in particular, there is no need to change or newly define the physical format of the recording medium.

Claims (15)

The bit pattern of the combined bit to be inserted at the predetermined position of the main data encoded by a predetermined recording encoding method is determined. Based on the sub data to be recorded on the recording medium together with the main data, Bit pattern determination means capable of determining a bit pattern, Combined bit inserting means for inserting a combined bit of the bit pattern determined by the bit pattern determining means into a predetermined position of the encoded main data; And recording means for recording the information formed by inserting the combined bit into the main data on a recording medium. The method of claim 1, The bit pattern determination means, And among the signal units forming the main data, a bit pattern is determined on the basis of the sub data with respect to a combined bit having a fixed bit pattern together and inserted between two signal units in a front-rear relation. The recording apparatus, characterized in that. The method of claim 2, The two signal units are a frame synchronization signal and a sub code sync. The bit pattern of the combined bit to be inserted at a predetermined position of the main data encoded by a predetermined recording encoding method is determined. Based on the sub data to be recorded on the recording medium together with the main data, A bit pattern determination procedure for determining a bit pattern, Combined bit inserting means for inserting combined bits of the bit pattern determined by the bit pattern determination procedure into a predetermined position of the encoded main data; And a recording procedure for recording the information formed by inserting the combined bit into the main data on a recording medium. The method of claim 4, wherein The bit pattern determination means, And among the signal units forming the main data, a bit pattern is determined on the basis of the sub data with respect to a combined bit having a fixed bit pattern together and inserted between two signal units in a forward and backward relationship. Recording method characterized in that. The method of claim 5, And the two signal units are a frame synchronization signal and a sub code sync. Reading means for extracting and reading the combined bits from at least a recording medium on which information consisting of the main data encoded by a predetermined recording encoding method and combined bits inserted into a predetermined position of the main data is recorded; And a data value obtaining means for obtaining a data value as sub data by using the bit pattern of the combined bit read by the reading means. The method of claim 7, wherein The reading means, From among the signal units forming the main data, a combination bit having a fixed bit pattern together and inserted between two signal units in the front-rear relation is extracted, The data value obtaining means And a data value as the sub-data based on a combination of at least one of the bit patterns included in the two signal units and the bit pattern of the combined bit. The method of claim 8, And the sub-synchronization signal and the frame synchronization signal. Reading means for extracting and reading the combined bits from at least a recording medium on which information consisting of main data encoded by a predetermined recording encoding method and combined bits inserted into a predetermined position of the main data is recorded; And a data value acquisition procedure as sub data using the bit pattern of the combined bit read out by the reading means. The method of claim 10, The reading order is Among the signal units forming the main data, a combination bit having a fixed bit pattern together and inserted between two signal units in a forward and backward relationship is extracted, The data value acquisition order is And a data value as the sub-data based on a combination of at least one of the bit patterns included in the two signal units and the bit pattern of the combined bit. The method of claim 11, The two signal units are a frame synchronization signal and a sub code sync. Information comprising main data encoded by a predetermined recording encoding method and combined bits inserted into a predetermined position of the main data is recorded; The combined bit is recorded with a bit pattern corresponding to a data value as sub data. The method of claim 13, The combined bit having a bit pattern according to the data value as the sub data is A recording medium, characterized in that it is inserted between two signal units in a front-rear relation having a fixed bit pattern among the signal units forming main data. The method of claim 14, And the two signal units are a frame synchronization signal and a sub code sync.