JP7619602B2 - Electronic device, computer program, data writing method, and data recovery method - Google Patents

Description

This disclosure relates to electronic devices and repair devices.

When data corruption occurs in a recording medium, technology is already known for repairing the damaged area. For example, technology is already known for recovering the VTOC (Volume Table Of Contents) in a magnetic disk device based on an auxiliary label (see, for example, Patent Document 1).

This technology targets magnetic disk devices that manage file management information as an area following the beginning of the magnetic disk, and at the same time store the management information of the corresponding file as an auxiliary label in the beginning area of each file. The VTOC is restored by writing the auxiliary label into the VTOC as a file label.

Japanese Patent Application Publication No. 2-62624

Conventional technology simply places the management information of a file as a backup at the beginning of the file in a data area separate from the management area (e.g., VTOC). Therefore, if the only backed-up management information in the data area is lost, the management area cannot be properly restored. In other words, conventional technology leaves room for improvement in terms of the likelihood of successful data restoration.

Therefore, according to one aspect of the present disclosure, it is desirable to provide a technology that can improve the likelihood of successful data recovery.

An electronic device according to one aspect of the present disclosure is an electronic device that is detachably connected to a data-writable recording medium, and includes a processing unit configured to execute a process of writing multiple pieces of special data for data repair to the recording medium as a special writing process. The special writing process is a process of writing each of the multiple pieces of special data to the recording medium so that they are scattered throughout the recording medium.

By distributing special data for data repair in advance within the recording medium through the special write process, even if some of the special data is lost within the recording medium, it is possible to repair the data on the recording medium based on the remaining special data. Therefore, according to one aspect of the present disclosure, it is possible to improve the chances of successful data repair on the recording medium.

According to one aspect of the present disclosure, the plurality of special data may include multiple overlapping pieces of the same special data. In this case, in the special write process, each of the multiple pieces of the same special data may be written to the recording medium such that they are positioned apart from one another within the recording medium.

By distributing multiple identical special data across the recording medium, even if some of the special data is lost, data on the recording medium can be repaired based on the remaining special data, increasing the chances of successful data repair.

According to one aspect of the present disclosure, a processing unit of an electronic device may execute a special write process to repair data on a recording medium having a data storage area and a management area for managing the storage location of data stored in the data storage area. In this case, in the special write process, special data for repairing the management area may be written to the data storage area. By distributing multiple pieces of special data in the data storage area, the likelihood that the management area can be properly repaired increases even if some of the special data is lost in addition to damage to the management area.

According to one aspect of the present disclosure, the special data may include information for identifying the type of device that uses the recording medium. Alternatively, the special data may include information for identifying the method of storing data on the recording medium by the device that uses the recording medium. According to one aspect of the present disclosure, the processing unit may appropriately repair the recording medium based on the information included in the special data and prior knowledge regarding the data structure in the recording medium.

According to one aspect of the present disclosure, the processing unit may be configured to execute a special write process following an initialization process on the recording medium. By sporadically writing the special data following the initialization process, it is possible to appropriately prepare for data corruption (including data loss) that may occur thereafter.

According to one aspect of the present disclosure, the processing unit may be configured to repeatedly execute a write operation of generated data, which is data generated by a predetermined process, to the recording medium. The processing unit may be configured to write multiple pieces of special data to the recording medium by repeatedly executing an operation of writing one or more pieces of special data in conjunction with the write operation of the generated data. With such a writing method, the processing load associated with writing the special data can be reduced.

According to one aspect of the present disclosure, the processing unit may be configured to repeatedly execute an operation of writing video data generated based on an input signal from a camera to a recording medium as a writing operation of generated data. By providing the technology of the present disclosure to an electronic device that records video data, it is possible to reduce the possibility that the video data stored in the recording medium becomes impossible to view due to an inability to repair the data.

According to one aspect of the present disclosure, the electronic device may further include a setting unit that sets the allocation density of special data to be realized in each of the multiple areas in the recording medium based on the number of times data has been corrupted in each of the multiple areas.

According to one aspect of the present disclosure, the electronic device may be configured such that the processing unit writes special data to each of a number of areas such that the number of special data pieces corresponds to the arrangement density set by the setting unit in each of the multiple areas. Such density setting for each area can improve data recovery capabilities.

According to one aspect of the present disclosure, the electronic device may further include a data repair unit that selects a repair method based on special data in the recording medium and repairs the data in the recording medium using the selected repair method.

According to one aspect of the present disclosure, there may be provided a repair device that is detachably connected to a recording medium on which multiple special data have been written by the electronic device, and that includes a data repair unit that selects a repair method based on the special data in the recording medium and repairs the data in the recording medium using the selected repair method. With this repair device, data repair in the recording medium can be appropriately performed based on the special data scattered throughout the recording medium.

According to one aspect of the present disclosure, a computer program may be provided for causing a computer to realize at least a portion of the functions of the electronic device or the repair device. According to one aspect of the present disclosure, a computer program may be provided for causing a computer to execute a special write process executed by the processing unit. According to one aspect of the present disclosure, a computer program may be provided for causing a computer to realize a function as a data repair unit in the repair device.

According to one aspect of the present disclosure, a computer-implemented method may be provided that relates to a method executed by the electronic device or repair device. For example, according to one aspect of the present disclosure, a computer-implemented data writing method may be provided that includes a procedure for writing a plurality of pieces of special data for data repair on a data-writable recording medium to the recording medium, the procedure including a procedure for writing each of the plurality of pieces of special data to the recording medium so as to be scattered within the recording medium. This data writing method can improve the likelihood of successful data repair on the recording medium.

According to one aspect of the present disclosure, there may be provided a data repair method executed by a computer, which selects a repair method based on special data in a recording medium to which multiple special data have been written by the data writing method, and repairs the data in the recording medium using the selected repair method. This data repair method can improve the chances of successful data repair on the recording medium.

FIG. 2 is a block diagram showing a configuration of a drive recorder. 11 is a flowchart showing a format-related process executed by a control unit. FIG. 2 is a diagram illustrating areas generated on a recording medium by formatting. FIG. 2 is an explanatory diagram regarding the arrangement of markers written to a recording medium. 11 is a flowchart showing a process executed by a control unit when writing data to be saved. FIG. 13 is a diagram illustrating a first arrangement of markers after data to be saved has been written; FIG. 13 is a diagram illustrating a second arrangement of markers after data to be saved has been written; FIG. 2 is a block diagram showing a configuration of a restoration device. 11 is a flowchart showing an analysis and repair process executed by a processor of the repair device. 10 is a flowchart showing a process executed by a control unit 10 in the second embodiment when data to be saved is written. 11A and 11B are explanatory diagrams regarding writing of data to be saved and markers. 11 is a flowchart showing a damage recording process executed by a control unit.

Exemplary embodiments of the present disclosure will now be described with reference to the drawings.
[First embodiment]
1 is a drive recorder that is mounted on a vehicle such as a four-wheeled automobile, etc. The drive recorder 1 is disposed, for example, in a position inside the vehicle cabin that allows it to record an image of the area ahead of the vehicle.

This drive recorder 1 includes a control unit 10, a camera 21, a microphone 23, an image processing circuit 25, a media reader/writer 30, a display 40, a speaker 50, and an input interface 60.

The control unit 10 includes a processor 11 and a memory 13. The processor 11 controls each part of the drive recorder 1 by executing processing according to a computer program stored in the memory 13. The processing executed by the control unit 10 described below may be understood as processing executed by the processor 11 according to a computer program.

Memory 13 includes RAM, ROM, and NVRAM, which is non-volatile RAM. The ROM stores computer programs. The RAM is used as a working area when executing processes according to the computer programs. The NVRAM is used to store setting data.

The camera 21 is installed so that it can capture images of the area in front of the vehicle. The camera 21 may be equipped with multiple cameras in order to capture images of multiple locations around the vehicle and inside the vehicle cabin. The microphone 23 is installed so that it can collect audio from the space in which the drive recorder 1 is installed.

The image processing circuit 25 generates video data for recording, including audio, based on the video signal input from the camera 21 and the audio signal input from the microphone 23, and inputs the video data to the control unit 10. The control unit 10 operates to record the video data on the recording media 35.

The recording medium 35 is a general-purpose recording medium that is manually attached to the media reader/writer 30 by the user. The recording medium 35 may be, for example, a recording medium that incorporates a NAND-type flash memory and a memory controller IC. An example of this recording medium 35 is an SD card.

The media reader/writer 30 is used by the control unit 10 to record video data on the recording media 35 and to read video data to be played back. The media reader/writer 30 is configured so that the recording media 35 can be attached/detached, and is configured to read and write data from/to the recording media 35 under the control of the control unit 10.

When writing data, the data specified by the control unit 10 is written via the media reader/writer 30 to an area in the recording medium 35 that corresponds to the data storage destination address specified by the control unit 10. In the recording medium 35, the data specified by the control unit 10 can be written to a physical address that corresponds to the logical address specified by the control unit 10.

The display 40 is, for example, a liquid crystal display, and is controlled by the control unit 10 to display various screens for the user, such as a setting screen and a playback screen. The speaker 50 is controlled by the control unit 10 to output various sounds.

The input interface 60 is configured to input operation signals from a user who operates the drive recorder 1 to the control unit 10. The input interface 60 may include operation switches and a touch panel on the display 40 as components.

The drive recorder 1 of this embodiment requires a recording medium 35 for recording video data, which is its main purpose. Therefore, before using the drive recorder 1, the user manually loads the recording medium 35 into the media reader/writer 30. The recording medium 35 is initialized, i.e., formatted, before recording video data.

When the control unit 10 recognizes the recording medium 35 attached to the media reader/writer 30 and a format command is input through the input interface 60, the control unit 10 executes the format-related processing shown in FIG. 2.

When formatting-related processing is started, the control unit 10 formats the recording medium 35 (S110). Formatting may be performed, for example, to build a specified file system. The file system may be a dedicated file system or a general-purpose file system. By formatting, a management area 35A and a data storage area 35B are generated in the recording medium 35, for example, as shown in FIG. 3.

The management area 35A is an area for managing the data stored in the data storage area 35B, and is used, for example, to store and manage the storage position of data in the data storage area 35B. The management area 35A is generated, for example, in an area following the first address of the recording medium 35. The data storage area 35B is generated in an area following the management area 35A within the recording medium 35.

When a known file system, such as the FAT system, is used, depending on the format, an area including a file allocation table is generated as the management area 35A. In this case, the file allocation table stores the storage location of each piece of data on a file-by-file basis in the data storage area 35B.

A characteristic feature of this embodiment is that after formatting the recording medium 35 in S110, the control unit 10 operates to write multiple markers, which are special data for data recovery, in a scattered manner within the recording medium 35, particularly within the data storage area 35B following the management area 35A, in preparation for data corruption that may occur in the recording medium 35 (S120, 130).

Specifically, following formatting of the recording medium 35, the control unit 10 executes a process of determining write positions in the data storage area 35B for a plurality of markers (S120). The control unit 10 can determine positions in the data storage area 35B to write the markers so that the markers are scattered at a preset density throughout the entire data storage area 35B, for example.

For example, the control unit 10 can determine the positions in the data storage area 35B where the markers are written so that the markers are spaced apart at regular intervals corresponding to the density. Alternatively, the control unit 10 can randomly determine a number of write positions corresponding to the product of the area size and density of the data storage area 35B using a random number generator. The determination of the write positions of the markers can be achieved, for example, by determining the clusters or sectors in the data storage area 35B where the markers are written.

Then, the control unit 10 executes a process of writing markers to each write position determined in the process of S120 in the recording medium 35 (S130). Figure 4 conceptually shows the data storage area 35B in which the markers are scattered. The hatched areas in Figure 4 and Figures 6 and 7 described below indicate the positions where the markers are stored.

The markers written to each write location may all be the same data. That is, multiple identical markers may be placed in the data storage area 35B. The marker may have a header that indicates that it is a marker. Following the header, the marker may have data describing an identification code for the model of the drive recorder 1 (hereinafter referred to as the "model ID").

Alternatively, the marker may have data describing the data storage method in data storage area 35B, for example, data describing the type or arrangement of data to be written to data storage area 35B. The marker may be simple data with a small amount of data, and may be data with a size smaller than the sector size in data storage area 35B.

According to this embodiment, as described above, in addition to initializing the recording medium 35, data recovery markers are written to the recording medium 35 in a scattered manner throughout the entire data storage area 35B.

After executing the format-related processing, when the control unit 10 writes the video data to be saved in the recording medium 35 to the data storage area 35B of the recording medium 35, the control unit 10 executes the processing shown in FIG. 5 to write the video data to the data storage area 35B while maintaining the marker in the recording medium 35. The video data is generated in predetermined units, such as a predetermined data size or a predetermined time interval. In accordance with the generation of the video data, the control unit 10 repeatedly executes the processing shown in FIG. 5.

That is, each time data to be saved to the recording medium 35 occurs, the control unit 10 starts the process shown in FIG. 5. When this process starts, the control unit 10 judges whether the destination area for the data to be saved contains a marker (S210). Here, "containing a marker" means that a continuous destination area contains an area in which a marker has been written.

When the control unit 10 determines that the destination area does not include a marker (No in S210), it writes the data to be saved to the destination area (S220). On the other hand, when the control unit 10 determines that the destination area includes a marker (Yes in S210), it generates data to be written that includes a marker in the data to be saved, and writes the generated data to be written to the corresponding destination area (S230).

As is well known, in recording media 35 including flash memory, the data erasure unit is larger than the sector size. Therefore, when the write destination area includes a marker, this area, including the marker, is erased in a predetermined erasure unit, and then the marker and the data to be saved are written, thereby writing the data to be saved while maintaining the state in which the marker is written to the recording media 35.

In S230, the data to be written is generated so that the marker is written again at the same position, and this can be written to the recording medium 35. Figure 6 conceptually shows the state of the data storage area 35B when the data to be saved is written. The areas shaded in black in Figure 6 and Figure 7 described below correspond to the areas where the data to be saved has been written.

As another example, the control unit 10 may operate in S230 to change the position of the marker so that the marker is placed at the end or beginning of the data to be saved, and write the data to be saved and the marker to the data storage area 35B.

In the example shown in FIG. 7, the marker is repositioned to the end of the data to be saved. By placing the marker before and after the data to be saved, the marker can indicate the division of the data to be saved. In this way, the control unit 10 writes the data to be saved to the data storage area 35B so as to maintain the state in which the marker is stored.

Next, a method for repairing the recording medium 35 using a marker will be described. Data repair of the recording medium 35 is achieved, for example, by a repair device 100 separate from the drive recorder 1.

The restoration device 100 shown in FIG. 8 is configured by installing a computer program for data restoration on a general-purpose personal computer. The computer program for data restoration is provided to a user, for example, via a wide area network.

The exemplary repair device 100 includes a processor 110, a memory 120, a storage 130, a user interface 140, a communication interface 150, and a media reader/writer 160.

The processor 110 executes processing according to a computer program stored in the storage 130. The memory 120 is used as a working area when the processor 110 executes processing.

The user interface 140 includes a display for displaying various information to the user and an input device for inputting user operation signals. The communication interface 150 is configured to be capable of communicating with an external server device via a wide area network.

The media reader/writer 160, like the media reader/writer 30 of the drive recorder 1, is configured to allow the recording media 35 to be attached/detached, and is configured to enable data reading and writing to the attached recording media 35.

The user can remove the recording medium 35 from the drive recorder 1, load the recording medium 35 into the media reader/writer 160 of the repair device 100, and then input a repair command via the user interface 140 to cause the repair device 100 to execute processing related to data repair of the recording medium 35.

When a repair instruction is input through the user interface 140, the processor 110 of the repair device 100 executes the analysis and repair process shown in FIG. 9. When the analysis and repair process starts, the processor 110 reads the marker recorded in the data storage area 35B of the recording medium 35 (S1010).

Then, the processor 110 determines whether the data structure of the management area 35A and the data storage area 35B in the recording medium 35 is normal based on the model ID or data storage method described by the marker (S1020).

To make this determination, a computer program for data repair can be distributed along with data describing the normal data structure for each model that has the capability of recording markers. Alternatively, the processor 110 can obtain the data describing the normal data structure from an external server device.

Then, the processor 110 analyzes the data structure in the recording medium 35 and compares it with a normal data structure to determine where the data is corrupted in the recording medium 35 (S1030).

If the processor 110 determines through this analysis that there is no damage (No in S1040), it ends the analysis and repair process. On the other hand, if it determines that there is damage (Yes in S1040), it executes data repair processing for the corresponding model and repairs the damaged data area in the recording media 35 (S1050).

Specifically, the processor 110 can repair the damaged portion according to a predetermined repair method corresponding to the combination of the model, the damaged portion, and the damaged state (S1050). The repair method can be predefined for each combination of the model, the damaged portion, and the damaged state.

Repairing the damaged area includes repairing the management area 35A and the data storage area 35B. If data corruption occurs in the management area 35A, even if the video data stored in the data storage area 35B is not damaged, it will be impossible to identify the storage location of the video data based on the information in the management area 35A, and the video data will not be able to be read from the recording media 35.

According to this embodiment, the management area 35A can be repaired based on the model ID or data storage method indicated by the marker, so that if the management area 35A is damaged, the recording medium 35 can be repaired to make the video data readable with a higher probability than before. The repair of the management area 35A can be realized based on prior knowledge of the data storage method so as to eliminate inconsistencies between the state of the data storage area 35B and the information stored in the management area 35A.

According to this embodiment, even if the video data in the data storage area 35B is corrupted, the video data can be appropriately repaired using a repair method based on prior knowledge of the data storage method, such as the recording format and data size of the video data. Repair can be achieved, for example, by removing the corrupted data portion and performing end-stage processing on the video data.

In addition, the term "repair" does not necessarily mean completely returning the recording medium 35 to the state it was in before the data was corrupted. Repair here also includes removing abnormal data that prevents the recording medium 35 from being used normally and putting the recording medium 35 back into a state where it can be used normally, for example, restoring the file system.

According to another example, the processor 110 can execute the processing from S1020 onwards based on the model ID or data storage method indicated by the marker read in S1010, using an inspection program and a repair program corresponding to the model ID or data storage method.

In other words, inspection programs and repair programs may be prepared for each model or data storage method, and the processor 110 can selectively use these inspection programs and repair programs based on information obtained from the marker to repair corrupted data in the recording medium 35.

Furthermore, the drive recorder 1 may be provided with a computer program for causing the processor 11 to realize functions similar to those of the computer program for data recovery installed in the recovery device 100.

That is, the control unit 10 of the drive recorder 1 may be configured to repair the data in the recording medium 35 attached to the media reader/writer 30 by executing the analysis and repair process shown in FIG. 9 as a process according to the computer program in accordance with an instruction from a user.

In addition, the repair device 100 may be provided at a facility of the manufacturer or seller of the drive recorder 1. A user of the drive recorder 1 can send the recording medium 35 to a facility that provides customer service, for example. The facility can use the repair device 100 to repair the data in the recording medium 35 received from the user, and return the repaired recording medium 35 to the user.

The technology of the first embodiment may be used not only for the recording medium 35 that is detachable from the media reader/writer 30, but also for data recovery in the memory 13 built into the drive recorder 1. That is, a marker may be written into the memory 13, and data recovery may be realized based on the marker.

[Second embodiment]
Next, the configuration of the drive recorder 1 of the second embodiment will be described. However, the drive recorder 1 of the second embodiment differs from the drive recorder 1 of the first embodiment only in the timing of writing a marker to the recording medium 35. Therefore, in the configuration of the drive recorder 1 of the second embodiment, the configuration different from the first embodiment will be selectively described below, and the description of the configuration common to the first embodiment will be omitted.

According to this embodiment, when an instruction to format the recording medium 35 is input, the control unit 10 of the drive recorder 1 executes only formatting of the recording medium 35. In other words, the control unit 10 executes the process of S110 among the format-related processes shown in FIG. 2, but operates not to execute the processes of S120 and S130.

Instead, the control unit 10 operates to write the markers to the recording medium 35 in stages in conjunction with writing the video data. To achieve this, when writing the video data to the data storage area 35B of the recording medium 35, the control unit 10 executes the process shown in FIG. 10 instead of the process shown in FIG. 5.

That is, each time data to be saved to the recording medium 35 is generated, the control unit 10 starts the process shown in FIG. 10, and first, as in the first embodiment, determines whether the destination area for the data to be saved includes a marker (S410).

When the control unit 10 determines that the write destination area includes a marker (Yes in S410), it generates write target data that includes a marker in the data to be saved, similar to the processing in S230, and writes the generated write target data to the corresponding write destination area (S430).

On the other hand, if the control unit 10 determines that the destination area does not include a marker (No in S410), it determines whether a marker has already been written in a predetermined range of area adjacent to the destination area (hereinafter referred to as the adjacent area) (S450). The predetermined range is predefined to a range according to the density of markers to be realized in the data storage area 35B.

When the control unit 10 determines that a marker has not been written in the adjacent area (No in S450), it generates write target data by adding a marker to the data to be saved, and writes the generated write target data to the corresponding destination area (S460). For example, the write target data may be data with a marker added to the beginning and/or end of the data to be saved.

Figures 11A and 11B are diagrams illustrating an example in which the control unit 10 sequentially writes a marker together with writing data to be saved, by adding a marker to the end of the data to be saved. As in the first embodiment, the blackened areas in Figures 11A and 11B indicate the write positions of the data to be saved, and the shaded areas indicate the write positions of the marker. Figure 11B shows a state in which further data has been written to data storage area 35B from the state shown in Figure 11A.

The marker is not limited to being added to the beginning and/or end of the data to be saved, but may be inserted at a midpoint between the beginning and the end of the data to be saved. In S450, it is possible to determine whether a marker has already been written in an adjacent area within a predetermined range based on the writing position of the marker when the marker is to be written.

In addition, if the control unit 10 determines that a marker has already been written in the adjacent area (Yes in S450), it writes the data to be saved to the destination area without adding a marker (S470).

Compared to the first embodiment, which performs a process of placing multiple markers scattered throughout data storage area 35B in a single operation following formatting, this embodiment has the advantage that markers can be written efficiently to data storage area 35B while distributing the processing load.

[Other embodiments]
Although the exemplary embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments and can adopt various aspects.

For example, in the second embodiment, the control unit 10 is configured to determine whether to write a marker together with the data to be saved based on the distance between adjacent markers. However, the control unit 10 may also determine whether to write a marker probabilistically.

For example, instead of the process of S450, the control unit 10 may be configured to acquire a random number, and if the acquired random number is a winning value, execute a process (S460) of writing a marker together with the data to be saved to the recording medium 35, and if the random number is a losing value, execute a process (S470) of writing only the data to be saved to the recording medium 35 without writing a marker. The winning value may be set to a number according to the density of the markers to be realized in the recording medium 35.

In addition, in the second embodiment, the write position of the marker may be predetermined, and instead of the process of S450, the control unit 10 may execute a process of determining whether the write destination area includes the predetermined write position of the marker, and if the write destination area includes the write position of the marker, proceed to S460 and execute a process of writing the marker to the write position together with writing the data to be saved. If the write destination area does not include the write position of the marker, the control unit 10 may proceed to S470 and write the data to be saved to the write destination area.

In addition, the density of the markers to be realized does not have to be a fixed value. For example, the density may be set to a value according to the number of occurrences of data corruption in the data storage area 35B. For example, the density may be set to a larger value as the number of occurrences of data corruption increases.

Moreover, the density of markers to be achieved may be determined for each partition when data storage area 35B is divided into multiple partitions. The density of markers for each partition may be determined according to the number of occurrences of data corruption in the corresponding partition. In other words, the density of markers may be set to a higher value for partitions with more data corruption.

To set the density of the markers according to the number of occurrences, the control unit 10 can repeatedly execute the corrupted recording process shown in FIG. 12. In the exemplary corrupted recording process, the control unit 10 determines whether data corruption has occurred in the recording medium 35 (S510).

When the control unit 10 determines that data corruption has occurred (Yes in S510), it updates the corruption history (S520) and further updates the marker density setting value for each partition (S530). The control unit 10 can store the number of data corruption occurrences and the marker density setting value for each partition in, for example, NVRAM.

Specifically, the control unit 10 can update the number of data corruptions stored in the NVRAM so as to increase the number of data corruptions in the section where data corruption has occurred by 1 (S520), and update the setting value of the marker density to a setting value corresponding to the updated number of data corruptions (S530). The update of the number of data corruptions and the setting value in the NVRAM can be performed simultaneously.

Alternatively, the recording medium 35 may be provided with an area for storing the number of data corruptions and the marker density setting value for each partition, and the control unit 10 may operate to update the number of data corruptions and the marker density setting value for each partition stored in the recording medium 35.

In addition, the writing of the markers may be performed immediately after formatting, or at a time other than when the video data is written. For example, the marker writing process may be performed when the usage rate of the processor 11 is low.

In the above embodiment, all the markers written to the data storage area 35B are the same data, but the information that should be written in one marker may be written in multiple markers.

For example, the first information may be written in a first marker, and the second information following the first information may be written in a second marker. A plurality of first markers and a plurality of second markers may be prepared, and these plurality of first markers and second markers may be recorded in the recording medium 35 in a distributed manner, either according to a certain rule or randomly. The second marker may be located at a position away from the first marker.

The markers written to the data storage area 35B may be configured as data having different information. For example, each marker may have a consecutive identification number in the order in which they are arranged on the recording medium 35. Each marker may have information about the creation time of the corresponding marker.

Each marker may have information about the type of data that will be stored in the area following the marker. Each marker may have information about the recording format of the video data that will be stored in the area following the marker. A marker may have information that describes the size to the next marker.

The drive recorder 1 may employ both a method of writing markers immediately after formatting as in the first embodiment, and a method of writing markers together with the data to be saved as in the second embodiment. For example, a conceivable method is to write markers at half the target density to the recording medium 35 immediately after formatting, and then write the remaining markers together with the data to be saved.

It goes without saying that the technology disclosed in the above embodiment is not limited to application to the drive recorder 1. This technology can be applied to various electronic devices that are detachably connected to a data-writable recording medium. The recording medium is not limited to a flash memory.

The functions of one component in the above embodiments may be distributed among multiple components. The functions of multiple components may be integrated into one component. Part of the configuration of the above embodiments may be omitted. At least part of the configuration of the above embodiments may be added to or substituted for the configuration of another of the above embodiments. All aspects included in the technical ideas identified from the wording of the claims are embodiments of the present disclosure.

1...Drive recorder, 10...Control unit, 11...Processor, 13...Memory, 21...Camera, 23...Microphone, 25...Image processing circuit, 30...Media reader/writer, 35...Recording media, 35A...Management area, 35B...Data storage area, 40...Display, 50...Speaker, 60...Input interface, 100...Repair device, 110...Processor, 120...Memory, 130...Storage, 140...User interface, 150...Communication interface, 160...Media reader/writer.

Claims (14)

An electronic device that is detachably connected to a data-writable recording medium,
a processing unit that executes a special write process for writing a plurality of special data for data recovery on the recording medium, the special data being written on the recording medium so as to be scattered within the recording medium ;
the specific data includes information for identifying a type of device that uses the recording medium,
An electronic device , wherein the information for identifying the type of device is information for repairing data in the recording medium using a repair method corresponding to the type of device . 2. The electronic device according to claim 1,
The plurality of special data include a plurality of duplicates of the same special data,
In the special writing process, a plurality of identical special data are written onto the recording medium so that the data are positioned apart from one another within the recording medium. 3. The electronic device according to claim 1,
the recording medium includes a data storage area and a management area for managing a storage location of data stored in the data storage area;
In the special write process, special data for repairing the management area is written into the data storage area as the special data. The electronic device according to any one of claims 1 to 3 ,
The processing unit is configured to execute the special writing process following an initialization process on the recording medium. The electronic device according to any one of claims 1 to 3 ,
The processing unit repeatedly executes a write operation of generated data, which is data generated by a predetermined process, onto the recording medium, and in the special write process, the electronic device writes the multiple special data onto the recording medium by repeatedly executing an operation of writing one or more special data in conjunction with the write operation of the generated data. 6. The electronic device according to claim 5 ,
The electronic device is configured so that the processing unit repeatedly executes an operation of writing video data generated based on an input signal from a camera onto the recording medium as the operation of writing the generated data. An electronic device that is detachably connected to a data-writable recording medium,
a processing unit that executes a special write process for writing a plurality of special data for data recovery on the recording medium, the special data being written on the recording medium so as to be scattered within the recording medium;
a setting unit that sets an allocation density of the special data to be realized in each of a plurality of areas in the recording medium based on the number of times data is corrupted in each of the plurality of areas ;
Equipped with
An electronic device in which the processing unit writes the special data to each of the multiple areas so that the special data is scattered in each of the multiple areas in a number corresponding to the placement density set by the setting unit. 8. The electronic device according to claim 7 ,
The special data includes information for identifying the type of device that uses the recording medium, or information for identifying the method of storing data on the recording medium by the device that uses the recording medium. The electronic device according to any one of claims 1 to 8,
The electronic device further comprises a data repair unit that selects a repair method based on the special data in the recording medium and repairs the data in the recording medium using the selected repair method. 7. A computer program for causing a computer to execute the special writing process in the electronic device according to claim 1. 9. A computer program for causing a computer to realize functions as the processing unit and the setting unit in the electronic device according to claim 7. 1. A computer-implemented method for writing data, comprising the steps of:
A procedure for writing a plurality of special data for data recovery on a data-writable recording medium, the procedure including a procedure for writing each of the plurality of special data on the recording medium so as to disperse the data within the recording medium;
the specific data includes information for identifying a type of device that uses the recording medium,
A data writing method , wherein the information for identifying the type of device is information for repairing data in the recording medium using a repair method corresponding to the type of device . 1. A computer-implemented method for data recovery, comprising:
a step of writing a plurality of pieces of special data for data recovery on a data-writable recording medium, the plurality of pieces of special data including information for identifying a type of device using the recording medium, onto the recording medium so as to be scattered within the recording medium;
a step of repairing the data in the recording medium using a repair method corresponding to a type of device identified from the special data in the recording medium;
Data recovery methods including . 1. A computer-implemented method for writing data, comprising the steps of:
a procedure for writing a plurality of special data for data recovery on a data-writable recording medium, the plurality of special data being written to the recording medium so as to be scattered within the recording medium ;
a setting step of setting a placement density of the special data to be realized in each of a plurality of areas in the recording medium based on the number of times data is corrupted in each of the plurality of areas;
Including,
A data writing method in which, in the writing step, the special data is written to each of the plurality of areas so that the special data is scattered in each of the plurality of areas in a number corresponding to the placement density set by the setting step .