JPH04336893A - Data write system for still camera - Google Patents

Abstract

PURPOSE:To realize the data write system by which a deleted picture data is easily revived. CONSTITUTION:A new picture data is written by selecting a picture data area not in use with priority. Thus, so long as a picture data not in use is in existence, the new picture data is not written to a picture data area subject to delete processing. Thus, since a picture data being an object of delete is saved by retarding the write of the picture data to the picture data subject to delete processing, even when some new picture data is written after delete processing, the picture data being a delete object is revived.

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 from a low address area to a high address area of a recording medium in the order of photography. A typical recording medium consists of an area where the image data itself is recorded and an information area for managing the image data. Information indicating whether or not image data is recorded in the corresponding data area is set in the information area. FIG. 4 shows an example of a conventional data writing method. This example shows a state in which five pieces of image data are recorded on a recording medium that can record eight pieces of image data. In this state, the process of erasing already recorded image data is usually achieved by rewriting only the information in the information area corresponding to this image data, without rewriting the image data itself. FIG. 5 shows an example in which image data 3 is deleted. In this example, the information area corresponding to image data 3 is rewritten with information that allows the user to recognize that this area is an empty area. therefore,
Following the principle that image data generated by new shooting is written in order from the empty area with the lowest address,
It is written in the image data 3 area.

0003

By the way, some of the erased image data may have been erased by mistake by the user, and there may be cases where the user wishes to restore this image data at a later date. However, with the conventional data writing method,
In the data area where the image data of the erased data remains, image data generated by new photography is preferentially written. This has caused a problem in that it has become impossible to restore the erased image data.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a data writing method that can solve these problems and easily restore erased image data.

[0005]

[Means for Solving the Problems] In order to solve the above problems, in the data writing method of the present invention, writing processing corresponds to writing of image data to a selected image data area and the image data area. A first flag is set in the information area, a second flag is set in the information area corresponding to a predetermined image data area in the erasure process, and an image data area to be written in the write process is selected. Search each information area,
If there is an information area for which neither flag is set, select the image data area corresponding to that information area, and select information for which there is no information area for which neither flag is set and the second flag is set. If there is an area, the image data area corresponding to the information area is selected.

[0006]

According to the data writing method of the present invention, when writing image data into an image data area, a first flag is set in the corresponding information area. Since this first flag is a flag that prohibits overwriting of the image data area, the image data area to which this flag is set will not be selected as the image data area to be written in the write process. Further, when image data is deleted 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 is performed, the image data to be erased can be restored until new image data is overwritten. By the way, when selecting the image data area to be written in the writing process, an unused image data area is selected preferentially, so as long as there is still an unused image data area, the second flag is set. 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]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 to 3 of the accompanying drawings.

This embodiment relates to a method for writing image data photographed with a digital still camera into a storage device such as an IC memory card built into the digital still camera. The memory map of this storage device is shown in Figure 3 (
Shown in a). According to the figure, the storage device 10 has 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 each image data. Eight information area groups are provided. Access processing such as writing and reading to each area of the image data area group and information area group is performed by the control device 2.
This is done with an instruction of 0. Each information area of the information area group is
It consists of an area where flags are stored and an area where additional information such as the date and time of photography is stored. 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. 3(b), these four types of flags are each defined as 8-bit data (first flag = '00000011', second flag = '00000').
010', 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 erasing processing for deleting image data from the image data area. In this erasing process, only the flag is set without actually erasing the image data. The third flag is set when writing image data to the image data area fails, and the fourth flag is set for an unused image data area. These flags are then used to specify the image data area in which image data is to be written.

Next, the processing procedure of the data writing method according to an embodiment of the present invention will be explained using the flowcharts of FIGS. 1 and 2. As a process, first, the information area corresponding to each image data area is examined to find whether there is an unused image data area. In other words, it is checked whether there is a fourth flag set in the information area of the unused image data area. Specifically, the pointer n to the image data area is set to an initial value of 1 (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 is set, the process moves to step 113, if it is not set, the pointer n is incremented (step 102), and if the pointer n is less than 8 (step 103), the process returns to step 101. . Thereafter, the process continues from step 101, and it is checked whether the fourth flag is set after the second information area. If the fourth flag is not set by the eighth information area, step 10
3, the pointer n becomes 8, and the process moves to step 104. The processing from step 104 to step 107 is as follows:
This is done by searching for an image data area where writing of image data has failed. In other words, by performing a process similar to the loop process from step 100 to step 103, it is checked whether the third flag is set in any information area. If it is found in this process that there is an information area in which the third flag is set, the process moves to step 113. Step 108 to Step 1
Similarly to the processing up to step 11, each information area is checked for the presence of the second flag, and an erased image data area is searched. If the second to fourth flags are not found in the above three loop processes, it is determined that the first flag is set in all information areas. In this state, image data has been written in all the image data areas, so it is assumed that there is no empty area and the process ends (step 112).
. If the second to fourth flags are found, the process moves to step 113 and the pointer number is set to n.

Next, the process waits until there is a request for photography (step 114), and when there is a request for photography, 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 will be set if writing of image data fails. Next, photographing is started (step 116), and image data of scenery, people, etc. is written into the image data area indicated by the pointer number. Then, the photographing ends when the photographing ends (step 118). Furthermore, additional information such as the 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). Even if the process ends between step 116 and step 120, for example because the battery is removed, the third flag set in step 115 remains, indicating that the image data area is the area where writing failed. I understand.

[0011]

As described above in detail, according to the data writing method of the present invention, new image data is written by preferentially selecting an unused image data area. Therefore, as long as there is an unused image data area, new image data will not be written to the erased image data area.

In this way, the image data to be erased can be saved by delaying the writing of image data into the erased image data area.
Even if some new image data is written, the image data to be erased can be restored.

[Brief explanation of the drawing]

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

FIG. 2 is a flowchart of the data writing method of this embodiment.

FIG. 3 is a conceptual diagram showing a memory map of the storage device of this 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

Claims (2)

[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 a storage device for writing image data to the storage device. In a data writing method for a still camera that has a control device that commands writing processing and erasing processing, the writing processing includes writing image data to a selected image data area and writing image data to an information area corresponding to the image data area. A first flag is set, a second flag is set in an information area corresponding to a predetermined image data area in the erasing process, and a second flag is set in an information area corresponding to a predetermined image data area in the writing process. When searching for an area, if there is an information area for which no flag is set, select the image data area corresponding to that information area, and select a second image data area that does not have any information area for which any flag is set. A data writing method for a still camera, characterized in that, if there is an information area with a flag set, an image data area corresponding to the information area is selected. 2. 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 a storage device for writing image data to the storage device. In a data writing method for a still camera that has a control device that commands writing processing and erasing processing, a fourth flag is set in all information areas as initial processing, and the writing processing is performed by setting a fourth flag in all information areas. Writing image data and setting the first flag to the information area corresponding to the image data area if the writing is successful; if writing fails, setting the first flag to the information area corresponding to the image data area. In the erasing process, a second flag is set in an information area corresponding to a predetermined image data area, and in the writing process, the image data area is selected by searching each information area. If there is an information area with the fourth flag set, the image data area corresponding to that information area is selected, and information where there is no information area with the fourth flag set and the third flag is set is selected. If there is an area, select the image data area corresponding to the information area, and if there is no information area with the fourth and third flags set and there is an information area with the second flag set, select the image data area corresponding to the information area. A data writing method for a still camera is characterized in that an image data area corresponding to the information area is selected.