JP2002041335A - Data recorder and data reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To select cluster size depending on files to be recorded. SOLUTION: The cluster size of hard disk is originally 8K byte. When a file (large capacity file) of data for recording regarding a video signal SV and an audio signal SA is recorded, the number N of clusters to be a recording unit is set as 2 and substantial cluster size is defined as 16K byte. In addition, when data DT of a text file, etc., is recorded, the number N of clusters to be the recording unit is set as 1 and the cluster size is defined as original 8K byte. The cluster size can be selected depending on the files to be recorded. Disadvantages due to the fact that the cluster size is small, namely, a delay of speed of recording and reproduction and impairment of real time nature are prevented by increasing the substantial cluster size, for example, when the file (large capacity file) of data for recording regarding the video signal SV and the audio signal SA is recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data recording device and a data reproducing device for handling a recording medium such as a hard disk. Specifically, by providing a setting unit for setting the number of clusters serving as recording units,
The present invention relates to a data recording apparatus and the like in which a cluster size can be selected depending on a file to be recorded.

[0002]

2. Description of the Related Art In recent years, data recording / reproducing apparatuses for recording / reproducing video data, audio data, and the like using a non-linearly accessible data recording medium such as a hard disk have become widespread.

FIG. 8 shows a configuration example of a hard disk. That is, the hard disk is in boot sector 2
01, FAT (File Allocation Table) area 202,
202 ', directory area 203 and data area 2
04.

The boot sector 201 contains an OS (Operati
ng System) to load (IPL: Initia
l Program Loader) is written. Further, information for managing the hard disk (information on the start sector and capacity of the FAT area, directory area, and data area) is also written in the boot sector.

In the FAT areas 202 and 202 ',
Each FAT is recorded. Here, the FAT area 20
FAT2 recorded in 2 'is a copy of FAT1 recorded in FAT area 202. FAT2 is FAT1
Is prepared for when it breaks. The FAT includes a number of FAT entries corresponding to a plurality of clusters obtained by dividing the data area. When a file is recorded in the corresponding cluster, the content of each FAT entry is the next cluster number in which the file is further stored (also indicating the number of the FAT entry to be followed next), or A value indicating that the file is the last cluster in which the file is recorded is written.

Further, the contents of each FAT entry include a value indicating that the corresponding cluster is not yet used and is usable, and the corresponding cluster is a defective cluster (including a sector which cannot be read / written due to a flaw). Is also written. FIG. 9 collectively shows the values written as the contents of the FAT entry and their meanings.

For example, when recording a file, the OS performs the following processing. The first empty cluster is found by searching the FAT, and the number of the cluster is
The first cluster number is registered in a directory entry of a directory area described later. Thereafter, data is written to the cluster, and when further data needs to be written, the corresponding FAT entry contains F
After searching the AT, the number of the cluster to which the data is to be written next is written, and then the data is written to the cluster in the same manner as described above. On the other hand, when no further data writing is necessary, the corresponding FAT
Write a value (0xFFFF) indicating that the file is the last cluster in which the file is recorded.

[0008] In the directory area 203, a plurality of directory entries are recorded. FIG. 10 shows a configuration example in which one directory entry has 32 bytes. This directory entry includes parameters such as a file name, a top cluster number, the number of clusters, and a data length.

FIG. 11 shows a directory area 203 and F
The relationship between the AT area 202 (202 ') and the data area 204 is shown. The directory entry in the directory area 203 is a file with a file name of “EXAMPLE_FILE”, which is written in the data area 204 using clusters 2 to 3 and has a data length of 20 Kbytes. Is shown. In addition,
The cluster size is 8K bytes.

Since the first cluster number of the directory entry is 0x0002, the FAT area 202 (20
By referring to the FAT entry with the FAT entry number of 2 ') of 0x0002, the file is stored in the data area 204.
It can be known that the data is written to the cluster 3 next to the cluster 2 of the FAT area, and by referring to the FAT entry having the FAT entry number of 0x0003 in the FAT area, the file is stored next to the cluster 3 of the data area 204. In the cluster 4 can be known.

In the configuration example of the hard disk shown in FIG. 8, the FAT area 202 (20
A procedure for searching for a file using the FAT described in 2 ′) will be described. First, the first FAT entry number is found to be 0x0002 from the head cluster number of the directory entry in the directory area 203, and the contents of the FAT entry with this number indicate that the next FAT entry number is 0x0003. Next, from the contents of the FAT entry having the FAT entry number of 0x0003, it is found that the next FAT entry number is 0x0004. Next, from the contents of the FAT entry having the FAT entry number of 0x0004, it is found that the next FAT entry number is 0x0008. In this case, the FAT entry number is 0x00
05, 0x0006 and 0x0007 are used by other files. Next, from the content of the FAT entry having the FAT entry number of 0x0008, it is found that the next FAT entry number is 0x0009. Next, since the content of the FAT entry whose FAT entry number is 0x0009 is 0xFFFF, it is known that this is the last FAT entry of the file.

[0012]

In a conventional hard disk, a cluster (a cluster of sectors) indicated by an FAT is used.
Is fixed, and the cluster size for recording a file cannot be arbitrarily selected. However, there are the following advantages and disadvantages when the cluster size is large and when the cluster size is small.

When the cluster size is small Advantage: The number of files that can be handled increases because the number of unused sectors decreases. Disadvantages: Since the number of sectors as a unit of access to a storage device such as an HDD decreases, the number of accesses increases, the access time increases, and the speed of recording and reproduction decreases.

When the cluster size is large Merits: Since the number of sectors as an access unit to a storage device such as an HDD is increased, the number of accesses is reduced, the access time is reduced, and the recording and reproducing speed is increased. Disadvantage: Since the number of unused sectors increases, the number of files that can be handled decreases.

When handling large-capacity files such as image files and audio files in real time, if the cluster size is small, the speed of recording and reproduction is reduced as described above.
There is a possibility that the real-time property is impaired. On the other hand, when handling a small-capacity file such as a text file, if the cluster size is large, the number of unused sectors increases and the number of files that can be handled is reduced. Therefore, it is desired that the cluster size can be selected depending on the file to be recorded.

Accordingly, an object of the present invention is to provide a data recording device or the like which can select a cluster size depending on a file to be recorded.

[0017]

According to the present invention, a data area comprising at least a plurality of clusters and a FAT for searching a cluster of a data area in which a predetermined file is recorded by following a chain of FAT entries are recorded. A data recording apparatus for handling a data recording medium having a FAT area and a directory area in which a directory entry having information of a file recorded in the data area is recorded, wherein the number of clusters N (N is Setting means for setting an integer greater than or equal to 1) and dividing a plurality of clusters in the data area into a set of N clusters set by the setting means, and referring to the FAT recorded in the FAT area, Data of a predetermined file is stored in one or a plurality of clusters in which all clusters in each cluster are free clusters. Means for recording, changing the contents of the FAT recorded in the FAT area in accordance with the recording of the predetermined file in the data area, and having information on the predetermined file to be recorded in the data area in the directory area; Means for recording a directory entry including value information of

According to the present invention, there is provided a data area comprising at least a plurality of clusters, and a FAT area for recording a FAT for searching a cluster of a data area in which a predetermined file is recorded by following a chain of FAT entries. And a directory area in which a directory entry having information on a file recorded in the data area is recorded. In the data area, a predetermined file divides a plurality of clusters into N clusters (N is an integer of 1 or more). A data recording medium that is recorded in one or more of a plurality of sets and that includes information on the value of N in a directory entry corresponding to a predetermined file recorded in a directory area. A data reproducing apparatus which handles information, and records information in a predetermined directory entry recorded in a directory area. Means for designating a specified file as a reproduction file, and tracing a chain of FAT entries related to the predetermined file with the FAT recorded in the FAT area using the information of the value of N included in the predetermined directory entry. Means for reproducing data of a predetermined file from the data area.

In the present invention, the data recording medium comprises a plurality of clusters. When a predetermined file is recorded on this data recording medium, the number N (N is an integer of 1 or more) of clusters as recording units is set. Then, the plurality of clusters in the data area are divided into sets of N clusters, and N clusters are referred to by referring to the FAT recorded in the FAT area.
Data of a predetermined file is recorded in one or a plurality of clusters in which all clusters in the cluster set are free clusters. In this case, since the data of the predetermined file is recorded in units of N clusters, the actual cluster size is N times the original cluster size.

As described above, when a predetermined file is recorded in the data area, the FAT recorded in the FAT area is
The contents of the AT are changed, and a directory entry having information of a predetermined file is newly recorded in the directory area. The FAT includes a number of FAT entries corresponding to a plurality of clusters in the data area.
When data of a predetermined file is recorded in units of N clusters, the content is changed for every N FAT entries. When the first cluster in which the data of the predetermined file is recorded is the cluster N × M, the top cluster number written in the directory entry is, for example, M.
The directory entry contains the information of the value of N described above, and is used when following the chain of the FAT entry during reproduction.

When a predetermined file is reproduced from the data recording medium, the predetermined file is first designated as a reproduction file. Then, by using the information of the value of N included in the predetermined directory entry having the information of the predetermined file, the FAT recorded in the FAT area is used to follow a chain of FAT entries relating to the predetermined file. The file data is played. For example, when the leading cluster number written in the predetermined directory entry is M described above, the first FAT entry number is calculated as M × N, and then the FAT entry chain is traced in units of N FAT entries. To be.

As described above, when a predetermined file is recorded, the actual cluster size can be set by setting the number N of clusters as recording units. That is, the cluster size can be selected according to the file to be recorded. For this reason, when recording a large-capacity file such as an image file or an audio file, by selecting a large cluster size, disadvantages due to a small cluster size, that is, recording and playback speeds are reduced, and real-time performance is reduced. Damage can be prevented. In addition, when recording a small-capacity file such as a text file, for example, selecting a small cluster size has a disadvantage that the cluster size is large, that is, the number of unused sectors increases and the number of files that can be handled decreases. Can be prevented.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a configuration of a data recording / reproducing apparatus 100 as an embodiment.

The data recording / reproducing apparatus 100 has a microcomputer (hereinafter, referred to as "microcomputer") 101 as a controller for controlling the operation of the entire apparatus. The microcomputer 101 includes a display unit 102 which includes a liquid crystal display element or the like and displays the state of the device and the like.
An operation unit 103 provided with a plurality of input keys for user operation is connected.

The apparatus 100 also includes a video input terminal 104 for inputting an analog video signal SV, and an A / A converter for converting the video signal SV input to the video input terminal 104 into a digital signal to obtain video data VD. A D converter 105, an audio input terminal 106 for inputting an analog audio signal SA, and an audio signal AD for converting the audio signal SA input to the audio input terminal 106 into a digital signal to obtain audio data AD
/ D converter 107.

The device 100 has an encoder / decoder 108. This encoder / decoder 10
Numeral 8 performs encoding processing on the data VD and AD output from the A / D converters 105 and 107 to obtain recording data, and decodes the recording data reproduced from the hard disk as described later. To obtain the data VD and AD.

For example, video data VD output from the A / D converter 105 is converted into, for example, MPEG2 (digital recording) recording data by encoding. In this case, the user can select a recording mode with a different compression ratio by operating the operation unit 103. The higher the compression ratio is, the lower the image quality is, but the longer the recording time can be.
The audio data AD output from the A / D converter 107 is encoded by, for example, an MPE.
G1 Layer 2 (digital recording) recording data.

The device 100 converts the video data VD obtained by the decoding process of the encoder / decoder 108 into an analog signal, and converts the analog video signal SV
, A video output terminal 110 for outputting an analog video signal SV obtained from the D / A converter 109, and an encoder / decoder 10
Audio data A obtained by the decoding process of FIG.
D is converted to an analog signal and the analog audio signal S
It has a D / A converter 111 for obtaining A and an audio output terminal 112 for outputting an analog audio signal SA obtained from the D / A converter 111.

The apparatus 100 has a data input / output terminal 113 for inputting and outputting data DT such as a text file and a program file. The data input / output terminal 113 is connected to the microcomputer 101.

Further, the apparatus 100 records the recording data obtained by the encoding process of the encoder / decoder 108 and the data DT inputted to the data input / output terminal 113 on the hard disk. It has a hard disk drive (HDD) 114 for reproducing DT. The recording / reproducing operation in the drive 114 is performed by the microcomputer 10
1 is controlled through the HD controller 115.

Here, the hard disk is configured as shown in FIG. That is, the hard disk
Boot sector 201, FAT (File AIIocation Tabl)
e) It has areas 202 and 202 ', a directory area 203 and a data area 204.

The data area 204 is composed of clusters having a size of 8 Kbytes. When data of a predetermined file is recorded in the data area 204, in the present embodiment, the number N of clusters as recording units is set. As will be described later, in the present embodiment, N = 1 is set when data DT input to the data input / output terminal 113 is recorded in the data area 204, while the encoder / decoder 108 is stored in the data area 204. When recording the recording data obtained by the encoding process, N = 2 is set.

When the number N of clusters as recording units is set as described above, a plurality of clusters in the data area are divided into sets of N clusters, and the FAT area 202
With reference to the FAT recorded in (202 '), data of a predetermined file is recorded in one or a plurality of clusters in which all clusters in the group are free clusters among the clusters of N clusters. In this case, the data of the predetermined file is N
Since recording is performed in units of clusters, the actual cluster size is N times the original cluster size.

The FAT recorded in the FAT area 202 (202 ') includes a plurality of clusters (8K
FAT entries each corresponding to one byte cluster. As described above, when data of a predetermined file is recorded in units of N clusters, N F
The contents are changed for each AT entry.

For example, when N is set to 2 (the actual cluster size is 16 Kbytes), an example of changing the contents of the FAT entry when recording data of a 48 Kbyte file is shown in FIGS. 3 will be described. It is assumed that the number of the user's use start FAT entry is 2.

Since one FAT entry of a 16 Kbyte cluster corresponds to two FAT entries of an 8 Kbyte cluster, the first free area search FAT entry is 1. In this case, when the contents of FAT entry 1 (two FAT entries with FAT entry numbers of 0x0002 and 0x0003) are examined, it is found that 0x0004 is already used and the process proceeds to FAT entry 2 (FIG. 2A). . FAT entry 2 (FAT entry number is 0x0004, 0x0
Examining the contents of the two FAT entries of 005, 0x000
FAT
Proceed to entry 3 (FIG. 2B).

When the contents of the FAT entry 3 (two FAT entries with FAT entry numbers of 0x0006 and 0x0007) are examined, both of them are 0x0000, and it is found that a continuous area of a 16-Kbyte cluster can be secured. Write data to clusters 6 and 7 corresponding to
Proceed to AT entry 4 (FIG. 2C). FAT entry 4 (FAT entry number is 0x0008,0x0
When the contents of the two FAT entries of 009 are checked, 0xFFF
Since F is known to be used already, FAT
Proceed to entry 5 (FIG. 3A).

Examination of the contents of FAT entry 5 (two FAT entries having FAT entry numbers of 0x000A and 0x000B) shows that both are 0x0000, indicating that a continuous area of 16 Kbyte cluster can be secured. FAT entry number corresponding to clusters 6 and 7 is 0x000
0x00 as the content of each of the 6,0x0007 FAT entries
At the same time as writing 05, data is written to the clusters A and B corresponding to the FAT entry 5, and the process proceeds to the FAT entry 6 (FIG. 3B). FAT entry 6 (FAT entry number is 0x000C, 0x0
When the contents of the two FAT entries of 00D are examined, both of them are 0x0000, and it is known that a continuous area of a 16-Kbyte cluster can be secured.
F whose FAT entry number corresponding to B is 0x000A, 0x000B
0x0006 is written as the content of each AT entry, and data is written to the clusters C and D corresponding to the FAT entry 6 (FIG. 3C). As a result, since all the data of the file of 48 Kbytes have been written, the FAT entry numbers corresponding to the clusters C and D are 0x000C and 0x000.
As the contents of each FAT entry of D, the final FA
Write 0xFFFF indicating T entry.

As described above, by changing the contents of the FAT entry, the FAT for the 8-Kbyte cluster in the FAT area 202 (202 ') functions as the FAT for the 16-Kbyte cluster. Figure 4 shows the 8K
Each FA when the FAT for the byte cluster is made to function as the FAT for the 16K byte cluster
The correspondence of T is shown.

In the directory area 203, a plurality of directory entries are recorded. When a predetermined file is recorded in the data area 204, the directory area 203
A directory entry having information on a predetermined file is newly recorded. FIG. 5 shows the directory entry (32
Byte). This directory entry contains the file name, starting cluster number, number of clusters,
It consists of parameters such as data length.

In this case, the data of the predetermined file is recorded in the data area 204 in units of N clusters. If the first cluster to be recorded is the cluster N × M, the head written in the directory entry The cluster number is, for example, M. The number of clusters written in the directory entry is the number of sets of N clusters in which data is recorded. In the present embodiment, this directory entry further includes the above-described information of the N value.

FIG. 6 shows the directory area 203 and the FA
The relationship between the T area 202 (202 ') and the data area 204 is shown. The directory entry 203a of the directory area 203 has a file name "EXAMPLE_FILE
a ". In this directory entry 203a, the file is set to N = 1, written in the data area 204 using clusters 2 to 3 in units of 8 Kbyte clusters, and has a data length of 20 Kbytes. It is shown that.

FIG. 7 shows a directory area 203.
, FAT area 202 (202 ′) and data area 20
4 is shown. The directory entry 203b of the directory area 203 has the file name "EXAMPL
"E_FILEb". This directory entry 203b indicates that the file is N =
2, the data area 204 is written in clusters 3 to 3 in units of 16 Kbyte clusters, indicating that the data length is 48 Kbytes.

The operation of the data recording / reproducing apparatus 100 shown in FIG. 1 will be described. By the operation of the operation unit 103 by the user,
An operation in the case where an instruction to record the signals SV and SA input to the input terminals 104 and 106 will be described. In this case, N = 2 is automatically set since the file capacity to be recorded generally increases. As a result, the cluster size as a recording unit is substantially 8 Kbytes × 2 = 16 Kbytes.

The analog video signal SV input to the video input terminal 104 is supplied to an A / D converter 105 and converted into a digital signal.
05 is supplied to the encoder / decoder 108. Also, audio input terminal 1
The analog audio signal SA input to A / D
The audio data AD is supplied to the converter 107 and converted into a digital signal. The audio data AD obtained from the A / D converter 107 is supplied to the encoder / decoder 108. In the encoder / decoder 108, the data V
An encoding process is performed on D and AD to generate recording data.

Then, the recording data is transferred to the hard disk drive 114 through the HD controller 115 and recorded on the hard disk. The operation of the microcomputer 101 when the recording data file is recorded on the hard disk as described above will be described in further detail (see FIGS. 2 and 3).

First, an empty cluster (8 Kbyte cluster × 2) is found by searching the FAT (functioning as a FAT for a 16 Kbyte cluster) recorded in the FAT area 202 (202 ′), and the cluster is found. (First cluster) number in the directory area 203
Is written as the leading cluster number in the directory entry corresponding to the file recorded in the. In this directory entry, "0x000
2 "is written.

Thereafter, data is written to the first cluster, and when no further data writing is necessary, a file is recorded in the corresponding FAT entry (two FAT entries for an 8 Kbyte cluster). Write a value (0xFFFF) indicating the last cluster. When it is necessary to write further data following the first cluster, the corresponding FAT entry contains the number of the next cluster (second cluster) to which data is to be written next after searching and finding the FAT. (Which also indicates the number of the FAT entry to be tracked).

Thereafter, data is written to the second cluster, and when no further data writing is required, a value (0xFFFF) indicating that this is the last cluster in which the file is recorded is stored in the corresponding FAT entry. )
Write. When further data needs to be written following the second cluster, the number of the cluster (third cluster) to which data is to be written next after the FAT has been searched and found is written in the corresponding FAT entry.
Thereafter, data is written to the third cluster, and the same operation as described above is repeated.

Next, a text file input to the input / output terminal 113 by the operation of the operation unit 103 by the user,
An operation when an instruction to record data DT such as a program file is given will be described. In this case, N = 1 is automatically set. As a result, the cluster size as a recording unit remains at 8 Kbytes.

The data DT input to the data input / output terminal 113 is transmitted to the microcomputer 101 and the HD controller 11.
5, transferred to the hard disk drive 114,
Recorded on the hard disk. As described above, the operation of the microcomputer 101 when the file of the data DT is recorded on the hard disk is as described above except that the FAT recorded in the FAT area 202 (202 ') functions as an original 8 Kbyte cluster. This is the same as when recording data is recorded. In the directory entry recorded in the directory area 203 corresponding to the file, “0x0001” is written as N value information.

Next, the operation at the time of reproduction will be described. At the time of this reproduction, a predetermined file in which information is recorded in a predetermined directory entry recorded in the directory area 203 is designated as a reproduction file by an operation of the operation unit 103 by the user.

A case where the information of the N value included in the predetermined directory entry having the information of the reproduction file is “0x0002” will be described. In this case, the reproduction file is a file of the recording data described above,
Are recorded with a cluster size of substantially 16 Kbytes.

Under the control of the microcomputer 101, in the hard disk drive 114, the data of the reproduction file is reproduced from the data area 204 of the hard disk. In this case, the FAT recorded in the FAT area 202 (202 ') functions as a FAT for a 16-Kbyte cluster, and the FAT traces a chain of FAT entries related to the reproduction file to thereby form a data area 204.
The data of the reproduction file is sequentially reproduced from one or a plurality of clusters (16 KB size).

For example, a file search procedure in a case where the areas have the relationship shown in FIG. 7 will be described. First, by multiplying the head cluster number 0x0003 of the directory entry 203b of the directory area 203 by 0x0002, the first F
It can be seen that the data is recorded in the cluster (8 Kbyte cluster) corresponding to the FAT entry with the AT entry number of 0x0006 and the FAT entry numbers of 0x0006 and 0x0007.

Next, the FAT entry numbers are 0x0006 and 0x00.
By multiplying 0x0005 which is the content of the FAT entry of 07 by 0x0002, the next FAT entry number is 0x000A,
It can be seen that data is recorded in the cluster (8 Kbyte cluster) corresponding to the FAT entry having the AT entry number of 0x000A and 0x000B.

Next, if the FAT entry number is 0x000A, 0x00
By multiplying 0x0006 which is the content of the FAT entry of 0B by 0x0002, the next FAT entry number is 0x000C,
It can be seen that data is recorded in the cluster (8 Kbyte cluster) corresponding to the FAT entry having the AT entry number of 0x000C and 0x000D. Since the contents of the FAT entries having the FAT entry numbers of 0x000C and 0x000D are 0xFFFF, it can be known that the final FAT entry number is 0x000D.

The recording data reproduced from the hard disk is transferred to the encoder / decoder 108. The encoder / decoder 108 decodes the recording data to generate video data VD and audio data AD. The video data VD generated by the encoder / decoder 108 is supplied to a D / A converter 109 and converted into an analog signal. The analog video signal SV obtained from the D / A converter 109 is output to a video output terminal 110. You. Also,
The audio data AD generated by the encoder / decoder 108 is supplied to a D / A converter 111 and converted into an analog signal. An analog audio signal SA obtained from the D / A converter 111 is output to an audio output terminal 112.

A case where the information of the N value included in the predetermined directory entry having the information of the reproduction file is “0x0001” will be described. In this case, the reproduction file is a file of the data DT described above,
Is recorded with an original cluster size of 8 Kbytes.

Under the control of the microcomputer 101, in the hard disk drive 114, the data of the reproduction file is reproduced from the data area 204 of the hard disk. In this case, the FAT recorded in the FAT area 202 (202 ') functions as an original FAT for an 8 Kbyte cluster, and the FAT traces the chain of the FAT entry relating to the reproduction file to form the data area 2
The data of the reproduction file is sequentially reproduced from one or a plurality of clusters 04 (8 KB size). The data DT thus reproduced from the hard disk is output to the data input / output terminal 113.

For example, a file search procedure in a case where the areas have the relationship shown in FIG. 6 will be described. First, from the first cluster number 0x0002 of the directory entry 203a of the directory area 203, the FA of the first FAT entry number is 0x0002 and the FAT entry number is 0x0002.
Cluster corresponding to T entry (8K byte cluster)
It can be seen that the data is recorded in.

Next, the FA with the FAT entry number of 0x0002
It can be seen that the content of the T entry is 0x0004, the next FAT entry number is 0x0004, and data is recorded in a cluster (8 Kbyte cluster) corresponding to the FAT entry with the FAT entry number of 0x0004.

Next, the FA with the FAT entry number of 0x0004
It can be seen that the content of the T entry is 0x0008, the next FAT entry number is 0x0008, and data is recorded in a cluster (8 Kbyte cluster) corresponding to the FAT entry with the FAT entry number of 0x0008. And
The content of the FAT entry whose FAT entry number is 0x0008 is
Since it is 0xFFFF, the final FAT entry number is 0x00
It turns out that it is 08.

As described above, in the present embodiment, when recording a file (large-capacity file) of recording data relating to the video signal SV and the audio signal SA, the number N of clusters as a recording unit is used. Is set to 2,
The substantial cluster size is 16 Kbytes. Therefore, in this case, the disadvantage of the small cluster size, that is, the speed of recording and reproduction is reduced,
It is possible to prevent the real-time property from being impaired. When data DT such as a text file or a program file is recorded, the number N of clusters as a recording unit is set to 1, and the cluster size is originally 8 Kbytes. Therefore, in this case, it is possible to prevent a disadvantage caused by a large cluster size, that is, it is possible to prevent the number of unused sectors from increasing and the number of files that can be handled from decreasing.

In the above embodiment, 1 or 2 is set as the number N of clusters as recording units. However, the value of N is not limited to this. For example, when recording a file of recording data relating to the video signal SV and the audio signal SA, N = 32
The actual cluster size is 8 Kbytes × 32 =
It may be 256K bytes. In the above-described embodiment, N depends on the type of file to be recorded.
Although the value is set automatically, the user may operate the operation unit 103 to set the value arbitrarily.

In the above embodiment, the recording medium is a hard disk. However, the present invention can be applied to the case where the recording medium is another FAT type recording medium. It is.

[0067]

According to the present invention, when a predetermined file is recorded, the actual cluster size can be set by setting the number N of clusters as recording units, and the cluster size can be selected according to the file to be recorded. become able to. Therefore, for example, when recording a large-capacity file such as an image file or an audio file, by selecting a large cluster size, a disadvantage due to a small cluster size, that is, the speed of recording and reproduction is reduced,
It is possible to prevent the real-time property from being impaired. Also, when recording a small capacity file such as a text file, by selecting a small cluster size,
The disadvantage of the large cluster size, that is, an increase in the number of unused sectors and a decrease in the number of files that can be handled can be prevented.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a data recording / reproducing apparatus as an embodiment.

FIG. 2 is a diagram showing an example (1/2) of changing the content of a FAT entry when N = 2 is set.

FIG. 3 is a diagram illustrating an example (2/2) of changing the content of a FAT entry when N = 2;

FIG. 4 is a diagram showing a relationship between FAT entry numbers of an 8-Kbyte cluster and a 16-Kbyte cluster.

FIG. 5 is a diagram illustrating a configuration example of a directory entry.

FIG. 6 is a diagram showing a relationship (8 Kbyte cluster) between a directory area, a FAT area, and a data area.

FIG. 7 is a diagram showing a relationship between a directory area, a FAT area, and a data area (substantially 16 Kbyte cluster).

FIG. 8 is a diagram illustrating a configuration example of a hard disk.

FIG. 9 is a diagram illustrating values written as contents of a FAT entry and their meanings.

FIG. 10 is a diagram illustrating a configuration example of a directory entry.

FIG. 11 is a diagram showing a relationship among a directory area, a FAT area, and a data area.

FIG. 12 is a diagram illustrating a procedure for searching for a file.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 data recording / reproducing device 101 microcomputer 102 display unit 103 operation unit 104 video input terminal 105, 107 A / D converter 106 audio input terminal 108 encoder / decoder 109, 111 D / A converter 110 video output terminal 112 audio output terminal 113 data I / O terminal 114 Hard disk drive 115 HD controller 201 Boot sector 202, 202 'FAT area 203 Directory area 203a, 203b Directory entry 204 Data area

Claims (2)

[Claims] 1. A data area comprising at least a plurality of clusters; a FAT area for recording a FAT for searching a cluster of the data area on which a predetermined file is recorded by following a chain of FAT entries; A data recording apparatus for handling a data recording medium comprising a directory area in which a directory entry having information of a file recorded in an area is recorded, wherein the number N of clusters as a recording unit (N is an integer of 1 or more)
Setting means for setting a plurality of clusters of the data area into a set of N clusters set by the setting means, and referring to the FAT recorded in the FAT area, Means for recording data of a predetermined file in one or a plurality of sets in which all clusters in the set are empty clusters; and transferring the contents of the FAT recorded in the FAT area to the data area. Means for changing corresponding to the recording of the predetermined file, and recording a directory entry having information of the predetermined file recorded in the data area in the directory area and including information of the value of N. A data recording device, characterized in that: 2. A data area comprising at least a plurality of clusters; a FAT area in which a FAT for searching a cluster of the data area in which a predetermined file is recorded by following a chain of FAT entries is recorded; A directory area in which a directory entry having information of a file recorded in the area is recorded. In the data area, a predetermined file is formed by dividing a plurality of clusters into N clusters (N is an integer of 1 or more). A data recording medium recorded in one or more of a plurality of sets and a directory entry corresponding to the predetermined file recorded in the directory area includes information of the value of N. A data reproducing apparatus which handles information stored in a predetermined directory entry recorded in the directory area. Means for designating a predetermined file in which the FAT entry is recorded as a reproduction file; and using the information of the value of N included in the predetermined directory entry, the FAT of the FAT entry relating to the predetermined file in the FAT recorded in the FAT area. Means for reproducing the data of the predetermined file from the data area by following a chain.