JP2004078408A - Recording device and method, recording medium and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To record continuous data such as real-time AV data in a continuous recording region. <P>SOLUTION: In a step 1, a CPU controls an information recording medium I/F through a CPU bus to copy a file allocation table (FAT) of the information recording medium in a dynamic random access memory (DRAM) for the FAT. In a step S2, the CPU refers to the FAT of the DRAM for the FAT and detects all vacant cluster groups continuous by a prescribed number or more. In a step S3, the CPU generates vacant cluster group information including the head cluster addresses and terminal cluster addresses of the vacant cluster groups detected in the step S2, and records it in FIFO. This device is applicable to a hard disk recorder, video camera using a microdrive, or the like. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a recording apparatus and method, a recording medium, and a program, and particularly to a recording apparatus and method, a recording medium, and a recording medium suitable for recording a data file on an information recording medium according to a FAT (File Allocation Table) method. About the program.
[0002]
[Prior art]
Conventionally, as a format for recording and reproducing a data file on an information recording medium such as a hard disk, the FAT method has been known. The FAT method is supported by a personal computer equipped with an OS (Operating System) such as MS-DOS, WINDOWS (registered trademark) or the like, and can be said to be the most popular file format method. .
[0003]
The FAT method will be described. As shown in FIG. 1, the recording area of the information recording medium formatted by the FAT method is divided into physical recording units called sectors. Each sector has a predetermined capacity (for example, 512 bytes), and a sector address is given to each sector. Access to the information recording medium is performed in sector units.
[0004]
Further, the recording area of the information recording medium formatted by the FAT method is divided into logical recording units called clusters each composed of a predetermined number of sectors (for example, 64 sectors). Each cluster is assigned a cluster address. The management of reading and writing of a file from and to the information recording medium is performed in cluster units.
[0005]
That is, when the size of a file to be recorded is larger than the capacity of one cluster, the file is divided into a plurality of clusters and recorded. Conversely, if the size of the file to be recorded is smaller than the capacity of one cluster, only that file is recorded in one cluster.
[0006]
In a predetermined recording area of the information recording medium, a file allocation table (hereinafter referred to as FAT) which is referred to and updated when recording or reading a file, and a directory entry are recorded.
[0007]
The FAT is provided with spaces respectively corresponding to all clusters of the information recording medium. Therefore, the larger the capacity of the information recording medium, the larger the size of the FAT. Each space of the FAT is assigned a FAT address.
[0008]
In the space of the FAT address 0, information indicating whether the cluster of the cluster address CL0 is empty or has been used is recorded. When there is data continuing from the data recorded in the cluster of the cluster address CL0, the cluster address of the cluster in which the continuing data is recorded is recorded as the information indicating that the data has been used. If there is no data continuing from the data recorded in the cluster with the cluster address CL0 (that is, if the file ends with the data recorded in the cluster with the cluster address CL0), EOF (End Of File) is recorded. ing.
[0009]
Similarly, in the spaces of the FAT addresses 1, 2, 3,..., Information indicating whether the cluster of the cluster address CL1, 2, 3,.
[0010]
The directory entry contains, for each file, the file name, extension, attribute, reservation information, file creation time, file creation date, last access date, update date and time, and the cluster of the cluster in which the data at the beginning of the file is recorded. An address (hereinafter, referred to as a start cluster address) and a file size are recorded.
[0011]
The cluster address of the cluster where the FAT is recorded and the cluster address of the cluster where the directory entry is recorded are included in the management information recorded in the first sector of the information recording medium. The management information also includes information indicating the capacity of the information recording medium and the number of sectors that one cluster is composed of.
[0012]
The directory entry and the FAT will be specifically described. For example, as shown in FIG. 2, file A is divided into files A-1 to A-18, each of which has a cluster address CL1, CL2, CL3, CL5, CL6, CL110, CL112, CL113, CL114 of the information recording medium. , CL115, CL116, CL119, CL320, CL323, CL324, CL328, CL329, and CL330.
[0013]
In this case, the cluster address CL1 is recorded in the directory entry as the start cluster address of the file A.
[0014]
On the other hand, in the FAT, as shown in FIG. 3, the cluster address CL2 is recorded in the space of the FAT address 1, the cluster address CL3 is recorded in the space of the FAT address 2, and the cluster address CL is recorded in the space of the FAT address 3. CL5 is recorded. Hereinafter, although the description is omitted, the EOF is finally recorded in the space of the FAT address 330. In FIG. 3, it is assumed that information indicating that the corresponding cluster is empty is recorded in blank spaces such as FAT address 0, FAT address 4, and FAT address 7. That is, according to the FAT shown in FIG. 3, clusters such as the cluster addresses CL0, CL4, and CL7 are empty clusters.
[0015]
In this way, the FAT and directory entry updated each time a file is recorded on the information recording medium are used when the file is read.
[0016]
For example, a process of reading the file A from the information recording medium will be described. First, the directory entry and the FAT recorded on the information recording medium are copied to a built-in memory (DRAM (Dynamic Random Access Memory) or the like) of the reproducing apparatus. Then, the start cluster (in this case, the cluster address CL1) of the file A is read by referring to the directory entry of the internal memory, and the file A-1 is read from the cluster of the cluster address CL1.
[0017]
Next, referring to the FAT of the internal memory, the next cluster address CL2 is read from the space of the FAT address 1 corresponding to the cluster address CL1, and the file A-2 is read from the cluster of the cluster address CL2. Next, referring to the FAT of the internal memory, the next cluster address CL3 is read from the space of the FAT address 2 corresponding to the cluster address CL2, and the file A-3 is read from the cluster of the cluster address CL12.
[0018]
Thereafter, similarly, the files A-4 to A-18 are sequentially read, and finally, the EOF is read from the FAT address 330 corresponding to the cluster address CL330, thereby reading the file to the end. Recognition is made, and reading is completed.
[0019]
Next, a process of recording a file on the information recording medium will be described. First, the directory entry and the FAT recorded on the information recording medium are copied to the internal memory of the recording device.
[0020]
Then, by referring to the FAT of the internal memory, one empty cluster is detected, the data of the first cluster of the file is recorded in the detected empty cluster, and the next empty cluster is detected. The cluster address of the next detected free cluster is written in the FAT space corresponding to the free cluster where the data is recorded.
[0021]
Thereafter, similarly, data for one cluster is recorded in the empty cluster, and the FAT is updated accordingly. Then, the data up to the end of the file is recorded, and the EOF is written in the FAT space corresponding to the free cluster in which the end data is recorded.
[0022]
Thereafter, the directory entry in the internal memory is updated, the directory entry and the FAT in the internal memory are overwritten by the directory entry and the FAT in the information recording medium, and the recording of the file is completed.
[0023]
As described above, when reading or writing a file according to the FAT method, the FAT is copied from the information recording medium to the internal memory, and the FAT in the internal memory is referred to. This is because, for example, if a cluster address is detected with reference to the FAT of the information recording medium and data is read / written from / to the cluster of the detected cluster address, it takes time to move the head and the pickup of the information recording medium. This is because spending may cause a delay in reading and writing data.
[0024]
[Problems to be solved by the invention]
By the way, in the conventional method of writing a file on an information recording medium in accordance with the FAT method, one empty cluster is detected by referring to the FAT in the built-in memory, and writing data to the detected empty cluster is repeated. As described above, when the free clusters are searched one by one, the addresses of the free clusters that are sequentially detected are not always continuous, and the free clusters whose cluster addresses are separated may be detected before and after. is there.
[0025]
In such a case, it takes time to move the head and the pickup of the information recording medium every time one cluster of data is written, even though the FAT in the internal memory is referred to. If the data to be written is, for example, AV (Audio and Video) data for recording video and audio in real time, the data throughput is reduced, and the recorded video and audio are interrupted or dropped. There were challenges.
[0026]
The present invention has been made in view of such circumstances, and has as its object to enable continuous data such as real-time AV data to be recorded in a continuous recording area.
[0027]
[Means for Solving the Problems]
A recording apparatus according to the present invention comprises: a reading unit that reads an FAT of an information recording medium; and a unit recording area group in an empty state that continuously exists in a predetermined number or more of the information recording medium based on the FAT read by the reading unit. Detecting means for detecting the empty unit recording area group information based on the detection result of the detecting means; holding means for holding the empty unit recording area group information generated by the generating means; A recording unit for recording a data file in an empty unit recording area group of the information recording medium with reference to the empty unit recording recording area group information held by the unit, and a reading unit corresponding to the processing of the recording unit. Updating means for updating the read FAT; and overwriting means for overwriting the FAT of the information recording medium using the FAT updated by the updating means. And wherein the Mukoto.
[0028]
The vacant unit recording area group information may include at least a head address of a vacant unit recording area group continuously present for a predetermined number or more.
[0029]
The data file may be an MPEG2 program stream, and the predetermined number of empty unit recording area groups may correspond to the data amount of one GOP.
[0030]
A recording method according to the present invention includes a reading step of reading an FAT of an information recording medium, and a unit recording of a vacant unit which is continuously present in a predetermined number or more on the information recording medium based on the FAT read in the processing of the reading step. A detection step of detecting an area group, a generation step of generating empty unit recording area group information based on a result of the processing of the detection step, and holding of the empty unit recording recording area group information generated by the processing of the generation step. A holding step, a recording step of recording a data file in an empty unit recording area group of the information recording medium with reference to the free unit recording recording area group information held in the processing of the holding step, and a recording step. Correspondingly, an updating step of updating the FAT read in the processing of the reading step and a FAT updated in the processing of the updating step are performed. There are, characterized in that it comprises a overwriting step of overwriting the FAT information recording medium.
[0031]
The program of the recording medium according to the present invention includes a reading step of reading the FAT of the information recording medium, and an empty state continuously present on the information recording medium by a predetermined number or more based on the FAT read in the processing of the reading step. A detection step of detecting a unit recording area group, a generation step of generating free unit recording area group information based on a result of the processing of the detection step, and a free unit recording recording area group information generated in the processing of the generation step. A holding step of holding, a recording step of recording a data file in an empty unit recording area group of the information recording medium with reference to the free unit recording recording area group information held in the processing of the holding step, and In accordance with the processing, an updating step of updating the FAT read in the processing of the reading step, and an updating step in the processing of the updating step. By using the FAT, you must; and a overwriting step of overwriting the FAT information recording medium.
[0032]
A program according to the present invention comprises: a reading step of reading an FAT of an information recording medium; and a unit recording area in an empty state continuously present in a predetermined number or more on the information recording medium based on the FAT read in the processing of the reading step. A detection step of detecting a group, a generation step of generating free unit recording area group information based on a result of the processing of the detection step, and a holding of holding the free unit recording recording area group information generated in the processing of the generation step Step, a recording step of recording a data file in a unit recording area group in an empty state of the information recording medium with reference to the empty unit recording recording area group information held in the processing of the holding step, and a process corresponding to the recording step. An updating step of updating the FAT read in the processing of the reading step; and an FAT updated in the processing of the updating step. Using, characterized in that to execute processing including the overwriting step of overwriting the FAT information recording medium into a computer.
[0033]
In the recording apparatus and method, and the program according to the present invention, based on the FAT read from the information recording medium, a vacant unit recording area group continuously present on the information recording medium for a predetermined number or more is detected, Based on the result of the detection, free unit recording area group information is generated and held. The data file is recorded in the empty unit recording area group of the information recording medium with reference to the held empty unit recording recording area group information, and the read FAT is stored in accordance with the recording processing. Using the updated FAT, the FAT of the information recording medium is overwritten.
[0034]
The recording device may be an independent device, or may be a block that performs recording of the recording / reproducing device.
[0035]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an AV recording apparatus according to an embodiment of the present invention will be described with reference to the drawings.
[0036]
The AV recording apparatus detects, as a pre-recording process, a free cluster group that is continuous for a predetermined number or more from the FAT, and generates continuous free cluster group information in which the start cluster address and the end cluster address are recorded. At the time of recording, video and audio data (program stream data) are recorded in the continuous free cluster group with reference to the continuous free cluster group information generated in advance.
[0037]
FIG. 4 shows a configuration example of the AV recording device. The CPU 1 controls the drive 2 via the CPU bus 16, reads a control program stored in a recording medium 3 such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory, and reads the read control program; In response to user operation information input from the operation input unit 4 via the CPU bus 16, the operation of each unit of the AV recording apparatus is controlled to start and end. In particular, the CPU 1 controls an information recording medium interface (I / F) 14 via a CPU bus 16 and controls reading and writing of program stream data and the like from and to the information recording medium 15. Further, the CPU 1 refers to the FAT copied to the FAT block SDRAM 6 and generates continuous free cluster group information in which the starting cluster address and the ending cluster address of the free cluster group continuous for a predetermined number or more are recorded. I do.
[0038]
The operation input unit 4 includes a user interface such as operation buttons, receives an operation input by the user (an operation for instructing start of recording, an operation for instructing end of recording, and the like), and is transmitted to the CPU 1 via the CPU bus 16 as operation information. Output.
[0039]
The FAT recorded on the information recording medium 15 is copied to the volatile FAT DRAM 5 under the control of the CPU 1. The FAT copied to the FAT DRAM 5 is updated every time data of the program stream is recorded in a free cluster of the information recording medium 15 and is finally overwritten on the information recording medium 15. In the FIFO 6, the continuous free cluster group information generated by the CPU 1 is recorded.
[0040]
The video camera 7 captures an image of a subject, and sequentially outputs the obtained video signals to the video encoder 8. The video encoder 8 encodes video signals sequentially input from the video camera 7 according to a predetermined method (MPEG (Moving Picture Experts Group) 2 method or the like), and outputs the encoded video data to a mixer (MUX) 11. Output. The microphone 9 sequentially outputs the collected audio signals to the audio encoder 10. The audio encoder 10 encodes an audio signal sequentially input from the microphone 9 according to a predetermined method, and outputs the obtained encoded audio data to the mixer 11. The mixer 11 multiplexes the encoded video data input from the video encoder 8 and the encoded audio data input from the audio encoder 10, generates a program stream, and outputs the program stream to the buffer controller 12.
[0041]
The buffer controller 12 buffers the program stream data input from the mixer 11 in the data buffer 13, and requests the CPU 1 to write data each time the program stream data is accumulated in the data buffer 13 for one cluster. And outputs the accumulated data to the information recording medium I / F14. The data of the program stream stored in the data buffer 13 is held until the writing to the information recording medium 15 is successful.
[0042]
The information recording medium I / F 14 reads out data (directory entry, FAT, etc.) recorded on the information recording medium 15 under the control of the CPU 1. The information recording medium I / F 14 records the data of the program stream input from the buffer controller 12 at the cluster address specified by the CPU 1 based on the control from the CPU 1. The information recording medium I / F 14 overwrites the information recording medium 15 with the FAT updated on the FAT DRAM 5 under the control of the CPU 1.
[0043]
The information recording medium 15 includes a hard disk formatted according to the FAT method.
[0044]
Next, the recording pre-processing for generating the continuous free cluster information will be described with reference to the flowchart in FIG. This pre-recording process is started when the power of the AV recording device is turned on.
[0045]
In step S1, the CPU 1 controls the information recording medium I / F 14 via the CPU bus 16 to copy the FAT recorded on the information recording medium 15 to the FAT DRAM 6.
[0046]
In step S2, the CPU 1 refers to the FAT of the FAT DRAM 5 and detects all continuous clusters of a predetermined number or more. For example, if one sector is 512 bytes, one cluster is composed of 64 sectors, and the program stream to be recorded is 9 Mbps, the data amount of one GOP (Group Of Pictures) corresponds to 18 clusters. Search for consecutive free clusters.
[0047]
In step S3, the CPU 1 generates free cluster group information including the head cluster address and the end cluster address of the free cluster group detected in step S2, and records the information in the FIFO 6.
[0048]
In step S2, instead of detecting all the free cluster groups, a predetermined number of free cluster groups are detected according to the capacity of the FIFO 6, and the free cluster group information is recorded in the FIFO 6 by the number. You may. In this case, in the recording process described later, the free cluster group information of the FIFO 6 is referred to, and while data is recorded in the cluster of the information recording medium 15 by the amount of free space in the FIFO 6, step The processing of S1 to S3 may be executed to add the free cluster group information to the FIFO 6.
[0049]
This is the end of the description of the recording pre-processing.
[0050]
Next, the recording process will be described with reference to the flowchart in FIG. In this recording process, when a user performs an operation to instruct recording start, and in response thereto, the CPU 1 instructs each unit of the AV recording apparatus to start recording, and when each unit starts its operation (for example, video) (When the camera 7 outputs a video signal, the video encoder 8 outputs coded video data, the mixer 1 outputs a program stream, and data starts to accumulate in the data buffer 13).
[0051]
In step S11, the CPU 1 refers to the free cluster group information in the FIFO 6 and acquires the start and end cluster addresses of one free cluster group.
[0052]
In step S12, the CPU 1 waits until a write request is made from the buffer controller 12, and every time a write request is made from the buffer controller 12, the CPU 1 starts from the start cluster address of the free cluster group obtained in step S11 and ends with the end cluster address. Are sequentially output to the information recording medium I / F 14 via the CPU bus 16 together with the write command, one cluster address at a time, and the data of the program stream input from the buffer controller 12 is recorded on the information recording medium I / F 14. . By the processing in step S12, for example, data of a program stream for one GOP is recorded in a continuous free cluster group.
[0053]
After the recording of the program stream data in the free cluster group is completed, in step S13, the CPU 1 updates the FAT of the FAT DRAM 5 in accordance with the processing in step S12.
[0054]
In step S14, the CPU 1 determines whether the user has instructed the end of recording. If it is determined that the end of recording has not been instructed by the user, the process returns to step S11, and the subsequent processing is repeated. Thereafter, if it is determined in step S14 that the end of recording has been instructed, the process proceeds to step S15. In step S15, the CPU 1 controls the information recording medium 14 via the CPU bus 16 to overwrite the updated FAT on the FAT DRAM 5 with the FAT recorded on the information recording medium 15. This is the end of the description of the recording process.
[0055]
As described above, according to the AV recording apparatus to which the present invention is applied, it is possible to record a program stream in a continuous free cluster for one GOP or more. Therefore, the movement of the head and the pickup of the information recording medium 15 is slight during this recording period, so that a decrease in data throughput can be suppressed.
[0056]
Note that the information recording medium 15 on which the data stream is recorded by the AV recording apparatus to which the present invention is applied completely conforms to the normal FAT format. Can be accessed directly.
[0057]
The present invention can be applied not only to an AV recording apparatus for recording a program stream as in the present embodiment, but also to an apparatus for recording arbitrary data on an information recording medium formatted in the FAT system. It is.
[0058]
Incidentally, the series of processes described above can be executed by hardware, but can also be executed by software. When a series of processes is executed by software, a program constituting the software is installed in a computer (for example, CPU 1 in FIG. 4) incorporated in dedicated hardware, or by installing various programs, It is installed from a recording medium (for example, the recording medium 3 in FIG. 4) to, for example, a general-purpose personal computer that can execute various functions.
[0059]
This recording medium is provided separately from the computer to distribute the program to the user. The recording medium is a magnetic disk (including a flexible disk) on which the program is recorded, or an optical disk (CD-ROM (Compact Disc-Read Only Memory)). , A DVD (including a Digital Versatile Disc), a magneto-optical disk (including an MD (Mini Disc)), or a package medium such as a semiconductor memory, etc. It is provided with a ROM, a hard disk, or the like in which the provided program is recorded.
[0060]
In this specification, the steps of describing a program recorded on a recording medium include, in addition to processing performed in chronological order according to the described order, not only chronological processing but also parallel or individual processing. This includes the processing to be executed.
[0061]
【The invention's effect】
As described above, according to the present invention, continuous data such as real-time AV data can be recorded in a continuous recording area.
[Brief description of the drawings]
FIG. 1 is a diagram showing a sector which is a physical recording unit and a cluster which is a logical recording unit of an information recording medium.
FIG. 2 is a diagram illustrating a state where a file is divided into a plurality of clusters and recorded.
FIG. 3 is a diagram illustrating an example of a FAT corresponding to the state illustrated in FIG. 2;
FIG. 4 is a block diagram illustrating a configuration example of an AV recording device according to an embodiment of the present invention.
FIG. 5 is a flowchart illustrating recording pre-processing.
FIG. 6 is a flowchart illustrating a recording process.
[Explanation of symbols]
1 CPU, 3 recording medium, 4 operation input unit, 5 FAT DRAM, 6 FIFO, 12 buffer controller, 13 data buffer, 14 information recording medium I / F, 15 information recording medium

Claims (6)

In a recording apparatus for recording a data file on an information recording medium formatted by the FAT method,
Reading means for reading the FAT of the information recording medium;
Detecting means for detecting, based on the FAT read by the reading means, a unit recording area group in an empty state which continuously exists in the information recording medium by a predetermined number or more;
Generating means for generating free unit recording area group information based on the detection result of the detecting means,
Holding means for holding the free unit recording recording area group information generated by the generating means,
A recording unit that records the data file in an empty unit recording area group of the information recording medium with reference to the empty unit recording recording area group information held by the holding unit;
Updating means for updating the FAT read by the reading means in response to the processing of the recording means;
An overwriting means for overwriting the FAT of the information recording medium using the FAT updated by the updating means. 2. The recording apparatus according to claim 1, wherein the vacant unit recording recording area group information includes at least a head address of a vacant unit recording area group continuously present for the predetermined number or more. . The data file is an MPEG2 program stream,
2. The recording apparatus according to claim 1, wherein the predetermined number of unit recording area groups in an empty state correspond to a data amount of one GOP. In a recording method of a recording device for recording a data file on an information recording medium formatted by the FAT method,
A reading step of reading the FAT of the information recording medium;
Based on the FAT read in the processing of the reading step, a detecting step of detecting a unit recording area group in an empty state continuously present in a predetermined number or more in the information recording medium;
A generation step of generating free unit recording area group information based on a result of the processing of the detection step;
A holding step of holding the free unit recording recording area group information generated in the processing of the generating step,
A recording step of recording the data file in an empty unit recording area group of the information recording medium with reference to the empty unit recording recording area group information held in the processing of the holding step;
An updating step of updating the FAT read in the processing of the reading step, corresponding to the processing of the recording step;
An overwriting step of overwriting the FAT of the information recording medium using the FAT updated in the processing of the updating step. A program for a recording device for recording a data file on an information recording medium formatted by the FAT method,
A reading step of reading the FAT of the information recording medium;
Based on the FAT read in the processing of the reading step, a detecting step of detecting a unit recording area group in an empty state continuously present in a predetermined number or more in the information recording medium;
A generation step of generating free unit recording area group information based on a result of the processing of the detection step;
A holding step of holding the free unit recording recording area group information generated in the processing of the generating step,
A recording step of recording the data file in an empty unit recording area group of the information recording medium with reference to the empty unit recording recording area group information held in the processing of the holding step;
An updating step of updating the FAT read in the processing of the reading step, corresponding to the processing of the recording step;
An overwriting step of overwriting the FAT of the information recording medium using the FAT updated in the processing of the updating step, wherein the computer-readable program is recorded. A computer that controls a recording device that records a data file on an information recording medium formatted in the FAT format;
A reading step of reading the FAT of the information recording medium;
Based on the FAT read in the processing of the reading step, a detecting step of detecting a unit recording area group in an empty state continuously present in a predetermined number or more in the information recording medium;
A generation step of generating free unit recording area group information based on a result of the processing of the detection step;
A holding step of holding the free unit recording recording area group information generated in the processing of the generating step,
A recording step of recording the data file in an empty unit recording area group of the information recording medium with reference to the empty unit recording recording area group information held in the processing of the holding step;
An updating step of updating the FAT read in the processing of the reading step, corresponding to the processing of the recording step;
Using the FAT updated in the process of the updating step to execute a process including an overwriting step of overwriting the FAT of the information recording medium.

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