JP3080682B2 - Still camera data writing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for writing data to a storage medium in a still camera.

[0002]

2. Description of the Related Art Image data photographed using a digital still camera is sequentially recorded in the order of photographing from a lower address area to a higher address area of a recording medium. An ordinary recording medium includes an area in which image data itself is recorded and an information area for managing the area. In the information area, information as to whether image data is recorded in the corresponding data area is set. FIG. 4 shows an example of a conventional data writing method. This example shows a state in which five image data are recorded on a recording medium on which eight image data can be recorded. In this state, the process of erasing the already recorded image data is usually realized by rewriting only the information in the information area corresponding to the image data without rewriting the image data itself. FIG. 5 shows an example in which the image data 3 is deleted. In this example, the information area corresponding to the image data 3 is rewritten with information that can recognize that this area is an empty area. Therefore,
According to the principle that the image data generated by the new shooting is written in order from the empty area of the lower address,
The data is written in the area of the image data 3.

[0003]

By the way, among the erased image data, there is an image data which has been erased by a user by mistake, and there is a case where it is desired to restore the image data at a later date. However, in the conventional data writing method,
In the data area where the image data of the erased data remains, the image data generated by the new shooting is preferentially written. This makes it impossible to recover the erased image data, which is a problem.

An object of the present invention is to solve such a problem and to provide a data writing system capable of easily recovering erased image data.

[0005]

In order to solve the above-mentioned problems, in the data writing method according to the present invention, the writing process corresponds to writing of image data to a selected image data area and corresponding to the image data area. The first flag is set in the information area, the erasing processing sets the second flag in the information area corresponding to the predetermined image data area, and the selection of the image data area to be written in the writing processing is When each information area is searched, and there is an information area in which none of the flags are set, an image data area corresponding to the information area is selected, and there is no information area in which none of the flags are set, and If there is an information area for which the second flag is set, an image data area corresponding to the information area is selected.

[0006]

According to the data writing method of the present invention, the first flag is set in the corresponding information area when the image data is written in the image data area. Since the first flag is a flag for prohibiting overwriting of the image data area, the image data area to which this flag is set is not selected as the image data area to be written in the writing process. Also, at the time of erasing the image data from the image data area,
A second flag is set in the corresponding information area. In the erasing process, only this flag is set, and the image data to be erased is erased when new image data is overwritten. Therefore, even after the erasing process, the image data to be erased can be restored until new image data is overwritten. By the way, in the selection of the image data area to be written in the writing process, since the unused image data area is preferentially selected, the second flag is set as long as the unused image data area still remains. No new image data is written to the set image data area. Therefore, even if some new image data is written after the erasing process, the image data to be erased can be restored.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

This embodiment relates to a method of writing image data photographed by a digital still camera to a storage device such as an IC memory card built in the digital still camera. The memory map of this storage device is shown in FIG.
(A). As shown in the figure, the storage device 10 stores eight image data area groups from the first image data area to the eighth image data area and the first information area to the eighth information area corresponding to the respective image data. Eight information area groups are provided. Access processing such as writing and reading to and from the image data area group and the information area group is performed according to an instruction from the control device 20. Each information area of the information area group includes an area in which a flag is stored and an area in which additional information such as a shooting date and time is stored. Flags include
There are four types of flags from a first flag to a fourth flag depending on the importance of the image data written in the image data area. As shown in FIG. 3B, these four types of flags are respectively defined as 8-bit data (first data).
Flag = '00000011', second flag = '00000010', third flag = '00000001', fourth flag = '00000000'). Here, the first flag is set when image data is written in the image data area, and the second flag is set during erasure processing for deleting image data from the image data area. In this erasing process, the actual image data is not actually erased, but only the flag is set. The third flag is set when writing of image data to the image data area has failed,
The fourth flag is set for an unused image data area. Then, the image data area in which the image data is to be written is specified using these flags.

Next, the processing procedure of the data writing method according to one embodiment of the present invention will be described with reference to the flowcharts of FIGS. As processing, first, an information area corresponding to each image data area is checked to search for an unused image data area. That is, it is checked whether or not there is a fourth flag set in the information area of the unused image data area. Specifically, an initial value 1 is set to a pointer n to the image data area (step 100), and it is checked whether the fourth flag is set in the first information area corresponding to the first image data area (step 101). ). If the fourth flag has been set, the process proceeds to step 113; if not, the pointer n is incremented (step 102). If the pointer n is less than 8 (step 103), the process returns to step 101. . Thereafter, the process is continued from step 101, and it is checked whether or not the fourth flag is set in the second information area and thereafter. If the fourth flag has not been set up to the eighth information area, step 10
At 3, the pointer n becomes 8, and the process proceeds to step 104. The processing from step 104 to step 107 is as follows:
A search is performed to determine whether there is an image data area in which writing of image data has failed. That is, by performing the same processing as the loop processing from step 100 to step 103, it is checked whether the third flag is set in any of the information areas. If it is determined in this process that there is an information area in which the third flag is set, the process proceeds to step 113. Step 108 to Step 1
In the processes up to 11, as in the past, each information area is checked for a second flag, and the image data area that has been erased is searched. If the second to fourth flags are not found in the above three loop processes, it is determined that the first flags are set in all the information areas. In this state, since the image data has been written in all the image data areas, it is assumed that there is no empty area, and the processing is terminated (step 11).
2). Step 11 when the second to fourth flags are found
3 and the pointer number is set to n.

Next, the process waits until a photographing request is made (step 114). When a photographing request is made, a third flag is set in the information area of the image data area indicated by the pointer number (step 115). . By setting the third flag in advance, this flag is set when writing of image data has failed. Next, photographing is started (step 116), and image data of a landscape, a person, or the like is written in the image data area indicated by the pointer number. Then, the shooting ends when the shooting ends (step 118). Further, additional information such as a date is stored in the information area of the image data area indicated by the pointer number (step 119). If the writing is normal, the first flag is reset in this information area (step 120). If the processing is completed between steps 116 and 120, for example, because the battery is removed, the image data area is an area where writing failed because the third flag set in step 115 remains. I understand.

[0011]

As described above in detail, according to the data writing method of the present invention, writing of new image data is performed by preferentially selecting an unused image data area.
Therefore, as long as there is an unused image data area, no new image data is written to the erased image data area.

As described above, the image data to be erased can be stored by delaying the writing of the image data to the image data area that has been erased.
Even when some new image data is written, the image data to be erased can be restored.

[Brief description of the drawings]

FIG. 1 is a flowchart of a data writing method according to the present embodiment.

FIG. 2 is a flowchart of a data writing method according to the present embodiment.

FIG. 3 is a conceptual diagram illustrating a memory map of the storage device of the present embodiment.

FIG. 4 is a conceptual diagram showing a memory map of a conventional storage device.

FIG. 5 is a conceptual diagram showing a memory map of a conventional storage device.

[Explanation of symbols]

 10 storage device 20 control device

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Ikuyoshi Ito 1-1-21-17 Takashima, Suwa-shi, Nagano Chino Corporation (72) Inventor Masayuki Uchiyama 1-12-117 Takashima, Suwa-shi, Nagano Chino (56) References JP-A-3-220983 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04N 5/907 H04N 5/91-5/956

Claims (2)

(57) [Claims] 1. A storage device comprising an image data area group consisting of a plurality of image data areas and an information area group consisting of a plurality of information areas corresponding to each image data area, and writing of image data to the storage apparatus. In the data writing method of a still camera having a control device for instructing a write process and an erase process, the write process includes writing image data to a selected image data area and writing information to an information area corresponding to the image data area. The first flag is set, the erasing process sets a second flag in an information area corresponding to a predetermined image data area, and the selection of the image data area to be written in the writing processing is performed by selecting each information. If an area is searched and there is an information area in which none of the flags are set, an image data area corresponding to the information area is selected, and no flag is set. If there is no information area and there is an information area for which the second flag is set, an image data area corresponding to the information area is selected. 2. A storage device comprising an image data region group consisting of a plurality of image data regions and an information region group consisting of a plurality of information regions corresponding to each image data region, and writing of image data to the storage device. In a still camera data writing system having a control device for instructing a writing process and an erasing process, a fourth flag is set in all information areas as initial processing, and the writing processing is performed for a selected image data area. If the writing is successful, the first flag is set to the information area corresponding to the image data area. If the writing is successful, the first flag is set to the information area corresponding to the image data area. 3 is set, the erasing process sets a second flag in an information area corresponding to a predetermined image data area, and the selection of an image data area in the writing When the information area is searched for, and there is an information area in which the fourth flag is set, an image data area corresponding to the information area is selected, and there is no information area in which the fourth flag is set and the third flag is set. Is selected, an image data area corresponding to the information area is selected, and there is no information area in which the fourth and third flags are set and an information area in which the second flag is set. If there is a data writing method for a still camera, an image data area corresponding to the information area is selected.