JP2007013691A - Imaging device, controlling method thereof and program performing the same, and storage media - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging device capable of improving shooting performance while preventing a write failure to a storage media due to electromagnetic noise generated by the emission of a strobe light. <P>SOLUTION: A digital camera 100 comprises a frame memory 103 which buffers A/D converted image data and image data compression-coded by a later-described moving-image/still-image codec 108, a CPU 104 which controls various behaviors of the digital camera 100, a strobe light 105 which emits light to illuminate an object, and a control unit 109 to which instructions such as a sequential shooting mode setting etc. are inputted. External to the digital camera 100, there is provided a memory card 107 for storing image data transmitted from the frame memory 103. In the case of continuous shooting of still images, the CPU 104 controls the frame memory 103 so as to halt the writing of data into the memory card 107 upon an emission of the strobe light 105. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an imaging apparatus that stores captured moving images and still images in an external storage medium such as a memory card, a control method thereof, a program that executes the method, and a storage medium.

  In recent years, imaging devices such as digital cameras and digital video cameras that record captured data on an external storage medium such as a memory card have become widespread and their performance has been improved year by year. In such an imaging device, when continuous shooting is performed, usually, the image data captured in the buffer inside the imaging device is held immediately and the next shooting operation is started immediately, and the writing operation of the image data to the memory card is not performed. This is performed in parallel with the shooting operation in the background. That is, the continuous shooting speed is improved by continuing the shooting operation without waiting for the end of writing to a storage medium having a relatively low transfer speed such as a memory card.

  Here, in the imaging apparatus as described above, access to the memory card is often executed simultaneously with the shooting operation, and when shooting with strobe light emission, electromagnetic noise generated by the strobe light emission causes the memory card to generate electromagnetic noise. May be transmitted to the memory card via a signal line connected to, and a write error may occur in the memory card.

  In order to solve such a problem, Patent Document 1 includes a digital camera and a portable hard disk device as an example of an external device. The digital camera serves as a master and the hard disk device serves as a slave. An imaging system is disclosed that is configured to be able to transmit and receive various signals related to data and communication processing by known wireless communication.

This photographing system interrupts communication with the hard disk device when it detects a photographing preparation operation such as completion of charging of the strobe in the digital camera or an eyepiece operation to the optical viewfinder. As a result, it is possible to prevent a write error due to electromagnetic noise generated by strobe light emission.
JP 2003-198901 A

  However, in the above photographing system, communication with the hard disk device is interrupted when the photographing preparation operation is detected, so that the hard disk device cannot be accessed until the photographing operation is completed after the photographing preparation operation is performed. There is a problem that writing of data to the apparatus is delayed, and as a result, the photographing performance of the digital camera is lowered.

  An object of the present invention is to provide an imaging apparatus capable of improving shooting performance while preventing an error in writing to a storage medium due to electromagnetic noise generated by strobe light emission, a control method thereof, a program for executing the method, and It is to provide a storage medium.

  In order to achieve the above object, an imaging apparatus according to the present invention is an imaging apparatus that includes a read / write unit that reads / writes data from / to an external storage medium and a light-emitting unit that emits light toward a subject. And a control means for controlling the read / write means to interrupt the writing of data to the storage medium when the light emitting means emits light.

  According to the present invention, when the light emitting means emits light, the read / write means is controlled so as to interrupt the writing of data to the storage medium. Therefore, the storage medium caused by electromagnetic noise generated by light emission of the light emitting means such as a strobe Shooting performance can be improved while preventing errors in writing to the camera.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram schematically showing a configuration of an imaging apparatus according to an embodiment of the present invention.

  In FIG. 1, a digital camera 100 as an imaging apparatus includes an imaging unit 101 that converts a subject image and sound into an electrical signal to shoot a moving image or a still image, and a signal processing unit that performs A / D conversion on the converted electrical signal. 102, a frame memory (read / write means) 103 for buffering the converted image data and image data compressed and encoded by a moving image / still image codec 108 to be described later, and a moving image / still image for compressing or expanding the image data Codec 108, CPU 104 that controls the shooting operation by driving each member in digital camera 100, strobe (light emitting means) 105 that emits light toward the subject, card I / F 106, and recording / reproduction of image data , An interface for inputting instructions such as setting the continuous shooting mode, which will be described later, and manual setting for turning on / off the flash. An operation unit (setting unit) 109 serving as a case and a menu necessary for displaying a subject image captured by the imaging unit 101 or image data stored in a memory card 107 described later and making various settings of the digital camera 100 And a display unit 110 that performs display. A memory card (storage medium) 107 that is connected to the digital camera 100 via the card I / F 106 and stores the image data transferred from the frame memory 103 is provided outside the digital camera 100.

  The digital camera 100 also includes a charger (charging means) 105a for charging electricity used for light emission of the strobe 105, and a charge amount detecting means 105b for detecting the charging level of the charger 105a.

  Further, the digital camera 100 includes a shutter button 111a and a pressed position detecting unit 111b that detects a pressed position of the shutter button, for example, a fully pressed position or a half pressed position.

  When the shutter button 111a is pressed halfway, if the strobe is usable, the strobe 105 is turned on according to the exposure amount, and the charger 105a is charged. Subsequently, when the shutter button is fully pressed, the strobe 105 emits light based on the electricity charged in the charger 105 a and the subject image is taken into the imaging unit 101. The electrical signal converted by the imaging unit 101 is subjected to A / D conversion and appropriate image processing in the signal processing unit 102 and buffered in the frame memory 103 as image data. The image data buffered in the frame memory 103 is compression-encoded by the moving image / still image codec 108, buffered again in the frame memory 103, and then stored in the memory card 107 via the card I / F 106. Alternatively, uncompressed image data not subjected to compression encoding processing can be stored in the memory card 107 from the frame memory 103 via the card I / F 106.

  When transferring image data from the frame memory 103 to the memory card 107, a single block transfer (first writing mode) for transferring a single data block constituting a part of the image data at a predetermined time interval, and a plurality of data are transferred. Multiple block transfer (second write mode) in which a data block group of data blocks is transferred at a predetermined time interval is possible.

  The image data buffered in the frame memory 103 is transferred to the memory card 107 by single block transfer or multiple block transfer. The memory card 107 includes, for example, a Multi Media Card or an SD Memory Card, and is configured to be compatible with both single block transfer and multiple block transfer methods.

  Next, the two types of transfer methods will be described with reference to FIG.

  FIGS. 2A and 2B are diagrams for explaining a data block transfer method to the memory card 107 in FIG. 1. FIG. 2A shows single block transfer and FIG. 2B shows multiple block transfer.

  As shown in FIG. 2, the single block transfer shown in (1) transfers one data block as a unit. On the other hand, in the multiple block transfer shown in (2), data blocks consisting of n data blocks (n is a predetermined constant) are transferred as a unit, so that data can be transferred faster than single block transfer. It is. However, since multiple block transfer requires a long transfer time, reading and writing to the memory card 107 cannot be interrupted immediately. Even in multiple block transfer, it is possible to forcibly terminate the reading / writing to the memory card 107 during the transfer of the data block. However, since the subsequent return operation becomes complicated, the reading / writing is performed in the blank portion of the transferred data block group. It is desirable to interrupt.

  When the digital camera 100 performs a shooting operation, for example, continuous shooting of still images, the image data is held in the frame memory 103 before the data stored in the frame memory 103 is written to the memory card 107. Then, take the next picture. By performing writing to the memory card 107 in parallel with the shooting operation, continuous shooting performance during continuous shooting is improved.

  However, as described above, when continuous shooting is performed and multiple block transfer is selected, data transfer can be interrupted immediately in order to prevent mixing of electromagnetic noise due to flash emission. As a result, continuous shooting performance may be degraded.

  Therefore, in the present embodiment, the CPU 104 controls the frame memory 103 and the like so as to interrupt the writing of data to the memory card 107 when the strobe 105 emits light when taking a still image. On the other hand, in a situation where the strobe does not emit light, control is performed so that multiple block transfer is performed as much as possible. Further, the CPU 104 executes data writing processing shown in FIGS. 3 to 5 to be described later, and instructs to set a predetermined shooting operation, for example, a continuous shooting (continuous shooting) mode input to the operation unit 109, and the flash 105 to emit light. The frame memory 103 and the like are controlled so as to appropriately select single block transfer or multiple block transfer according to the possible state or the pressed position of the shutter button 111a detected by the pressed position detection unit 111b.

  Note that the flashable state of the strobe 105 indicates, for example, a state where the charging level of the charger 105a is equal to or higher than a predetermined value or a strobe light emission being in a standby state. The CPU 104 executes single block transfer or multiple block transfer according to the charge level of the charger 105a detected by the charge amount detection means 105b and the on / off setting of strobe light emission.

  Next, the data writing operation to the memory card 107 will be specifically described.

  FIG. 3 is a flowchart for explaining the first data writing process executed by the digital camera 100 of FIG.

  In FIG. 3, first, it is determined whether or not data that has not been written to the memory card 107 is stored in the frame memory 103 (step S <b> 31), and when data that has not been written is stored in the frame memory 103. Then, it is determined whether or not the continuous shooting mode is set by the operation unit 109 (step S32). When the continuous shooting mode is set, it is determined whether or not the flash 105 is set to be able to emit light ( In step S33), if the strobe 105 is set to emit light, single block transfer is executed (step S34).

  If the continuous shooting mode is not set in step S32 or if the strobe 105 is not set to emit light in step S33, multiple block transfer is executed (step S35), and the process returns to step S31.

  If the data not written in step S31 is not stored in the frame memory 103, this process is terminated.

  According to the first data writing process of FIG. 3, when the continuous shooting mode is set by the operation unit 109 (YES in step S32), and the strobe 105 is set to be able to emit light (YES in step S33). ), Since single block transfer is selected, single block transfer can be executed when the strobe 105 is ready to emit light. Thereby, the data writing to the memory card 107 can be interrupted immediately in accordance with the flash emission. In a setting situation where the strobe is not fired, data can be transferred at high speed by multiple block transfer.

  FIG. 4 is a flowchart for explaining the second data writing process executed by the digital camera 100 of FIG.

  In FIG. 4, first, it is determined whether or not data that has not been written to the memory card 107 is stored in the frame memory 103 (step S41), and when data that has not been written is stored in the frame memory 103. Then, it is determined whether or not the strobe is in a standby state, that is, whether or not charging of the strobe 105 has been completed (step S42). When charging of the strobe 105 has been completed, single block transfer is executed. (Step S43).

  If charging of the flash 105 is not completed in step S42, multiple block transfer is executed (step S44), and the process returns to step S41.

  When the data not written in step S41 is not stored in the frame memory 103, this process is terminated.

  According to the second data writing process of FIG. 4, when charging of the strobe 105 is completed (YES in step S42), single block transfer is selected, and charging of the strobe 105 is not completed (step S42). NO), multiple block transfer is selected, so that single block transfer can be executed when the strobe 105 is fully charged. Thereby, the data writing to the memory card 107 can be interrupted immediately in accordance with the flash emission. In addition, at the timing when the strobe is not emitted, data can be transferred at high speed by multiple block transfer.

  FIG. 5 is a flowchart for explaining a third data writing process executed by the digital camera 100 of FIG.

  In FIG. 5, first, it is determined whether or not data that has not been written to the memory card 107 is stored in the frame memory 103 (step S 51), and when data that has not been written is stored in the frame memory 103. Then, it is determined whether or not the shutter button 111a has been pressed (step S52). When the shutter button 111a is pressed, it is determined whether or not the shutter button 111a is pressed half or more (that is, half pressed or fully pressed) (step S53). It is determined whether or not the charging level of the device 105a is equal to or higher than a predetermined value (step S54). When the charging level is higher than the predetermined value, single block transfer is executed (step S55).

  When the shutter button 111a is not pressed in step S52, when the shutter button 111a is not pressed half or more in step S53 (that is, when the shutter button 111a is not half-pressed or fully pressed), or the charging level of the charger 105a in step S54 Is less than the predetermined value, multiple block transfer is executed (step S56), and the process returns to step S51.

  If data that has not been written in the memory card 107 is not stored in the frame memory 103 in step S51, the present process is terminated.

  According to the third data writing process of FIG. 5, when the shutter button 111a is depressed more than half and the charge level of the charger 105a is equal to or higher than a predetermined value, single block transfer is selected, and the shutter button is Since multiple block transfer is selected when half or more of the buttons are not pressed or when the charge level of the charger 105a is less than a predetermined value, single block transfer is executed according to the pressed position of the shutter button 111a and the charge level of the charger 105a. can do. Thereby, the data writing to the memory card 107 can be interrupted immediately in accordance with the flash emission. In addition, data can be transferred at high speed by multiple block transfer until just before the strobe light is emitted.

  6A and 6B are diagrams for explaining data block transfer when the data writing process of FIG. 5 is executed. FIG. 6A shows a case of a conventional digital camera, and FIG. 6B shows the present embodiment. The case of the digital camera 100 is shown.

  As shown in FIG. 6A, in the conventional digital camera, normally, multiple block transfer is performed at a speed higher than single block transfer, and when the shutter button is half-pressed, the data transmitted this time is transmitted. After transferring the block group, the transfer of the next data block group is interrupted until the shutter button is fully pressed. After the shutter button is fully pressed and flash is emitted to the subject, multiple block transfer is performed again.

  On the other hand, as shown in FIG. 6B, in the digital camera 100 according to the present embodiment, multiple block transfer is performed in a state in which no photographing operation is performed, and when the shutter button is half-pressed, After the data block group transmitted this time is transferred, the transfer is continued by switching from the next transfer to a single block transfer with a short time per transfer. Furthermore, when the user presses the shutter button fully to instruct the shooting operation, after transferring one data block transmitted this time, the next and subsequent data blocks are transferred until the flash is emitted to the subject. Interrupt. After the flash is emitted to the subject, multiple block transfer is performed. Therefore, as compared with the data block transfer by the conventional digital camera, the time for interrupting the transfer is shortened, and the writing to the memory card 107 can be performed at high speed and efficiently.

  As described above, according to the present embodiment, when the strobe 105 emits light, the frame memory 103 is controlled so as to interrupt the writing of data to the memory card 107, so that electromagnetic noise generated by the strobe light emission is prevented. Shooting performance can be improved while preventing a writing error to the memory card 107 caused by the error.

  Further, according to the present embodiment, since the frame memory 103 is controlled so as to select single block transfer or multiple block transfer according to a predetermined shooting operation, transfer of data to the memory card 107 is immediately stopped. By switching to a transfer method that can perform the transfer and continuing the transfer, it is possible to reliably improve the shooting performance.

  Another object of the present invention is to supply a storage medium recording software program codes for realizing the functions of the above-described embodiments to the imaging apparatus, and store the computer (or CPU, MPU, etc.) in the imaging apparatus in the storage medium It is also achieved by reading and executing the programmed program code.

  In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the program code and the storage medium storing the program code constitute the present invention.

  Examples of the storage medium for supplying the program code include a floppy (registered trademark) disk, a hard disk, a magneto-optical disk, a CD-ROM, a CD-R, a CD-RW, a DVD-ROM, a DVD-RAM, and a DVD. -RW, DVD + RW, magnetic tape, nonvolatile memory card, ROM, etc. can be used. Alternatively, the program code may be downloaded via a network.

  Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an OS (operating system) running on the computer based on the instruction of the program code. A case where part or all of the actual processing is performed and the functions of the above-described embodiments are realized by the processing is also included.

   Further, after the program code read from the storage medium is written in a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function expansion is performed based on the instruction of the program code. This includes the case where the CPU or the like provided in the board or the function expansion unit performs part or all of the actual processing, and the functions of the above-described embodiments are realized by the processing.

1 is a block diagram schematically showing a configuration of an imaging apparatus according to an embodiment of the present invention. FIGS. 2A and 2B are diagrams illustrating a method of transferring data blocks to the memory card 107 in FIG. 1, where (1) indicates single block transfer and (2) indicates multiple block transfer. 3 is a flowchart for explaining a first data writing process executed by the digital camera of FIG. 1. 7 is a flowchart for explaining a second data writing process executed by the digital camera of FIG. 1. 7 is a flowchart illustrating a third data writing process executed by the digital camera of FIG. 1. FIGS. 6A and 6B are diagrams for explaining data block transfer when the data writing process of FIG. 5 is executed, in which FIG. 5A shows the case of a conventional digital camera, and FIG. This case is shown.

Explanation of symbols

100 Digital Camera 101 Imaging Unit 102 Signal Processing Unit 102
103 Frame memory 104 CPU
105 Strobe 106 Card I / F
107 Memory Card 108 Video / Still Image Codec 109 Operation Unit 110 Display Unit

Claims (14)

In an imaging apparatus comprising a read / write unit for reading / writing data from / to an external storage medium and a light emitting unit for emitting light toward a subject,
An image pickup apparatus comprising: control means for controlling the read / write means so as to interrupt writing of data to the storage medium when the light emitting means emits light. The read / write means has a first write mode for writing a single data block to the storage medium at a predetermined time interval, and a second write mode for writing a data block group consisting of a plurality of data blocks to the storage medium at a predetermined time interval. Write mode,
The imaging apparatus according to claim 1, wherein the control unit controls the read / write unit to select the first writing mode or the second writing mode according to a predetermined photographing operation. It has setting means to set the continuous shooting mode for continuous shooting,
The control means controls the reading / writing means so as to select the first writing mode when the setting means sets the continuous shooting mode and the light emitting means is capable of emitting light. The imaging apparatus according to claim 2. Charging means for charging electricity used for light emission of the light emitting means, and charge amount detecting means for detecting a charge level of the charging means,
The predetermined photographing operation includes a charging operation of the charging means,
The control means selects the first writing mode when the charging of the charging means is completed, and selects the second writing mode when the charging of the charging means is not completed. The image pickup apparatus according to claim 2, wherein the means is controlled. A pressing position detecting means for detecting a pressing position of the shutter button;
The predetermined photographing operation includes a pressing operation of the shutter button,
The control means selects the first writing mode when the shutter button is pressed half or more, and selects the second writing mode when the shutter button is not pressed. The image pickup apparatus according to claim 2, wherein the means is controlled.   The control means sets the first writing mode when the shutter button is pressed more than half and the charge level of the charging means is equal to or higher than a predetermined value, and when the shutter button is not pressed. 6. The imaging apparatus according to claim 4, wherein the read / write unit is controlled to select the second writing mode when a charge level of the light emitting unit is less than a predetermined value. A method for controlling an imaging apparatus, comprising: a reading / writing unit that reads / writes data from / to an external storage medium; and a light emitting unit that emits light toward a subject,
A control method comprising: a control step of controlling the read / write means so as to interrupt the writing of data to the storage medium when the light emitting means emits light. The read / write means has a first write mode for writing a single data block to the storage medium at a predetermined time interval, and a second write mode for writing a data block group consisting of a plurality of data blocks to the storage medium at a predetermined time interval. Write mode,
8. The control method according to claim 7, wherein the control step controls the read / write unit to select the first writing mode or the second writing mode in accordance with a predetermined photographing operation. It has a setting step to set the continuous shooting mode for continuous shooting,
The control step controls the read / write unit to select the first write mode when the continuous shooting mode is set by the setting step and the light emitting unit is in a state capable of emitting light. The control method according to claim 8, wherein: A charging step of charging the charging means with electricity used for light emission of the light emitting means, and a charge amount detecting step of detecting a charge level of the charging means,
The predetermined photographing operation includes a charging operation of the charging means,
The control step selects the first writing mode when the charging of the charging unit is completed, and selects the second writing mode when the charging of the charging unit is not completed. 9. The control method according to claim 8, wherein the means is controlled. A pressing position detecting step for detecting a pressing position of the shutter button;
The predetermined photographing operation includes a pressing operation of a shutter button,
The control step selects the first writing mode when the shutter button is pressed halfway or more, and selects the second writing mode when the shutter button is not pressed. 9. The control method according to claim 8, wherein the means is controlled.   In the control step, the first writing mode is set when the shutter button is pressed more than half, and the charge level of the light emitting means is a predetermined value or higher, and the shutter button is not pressed. 12. The control method according to claim 10, wherein the read / write unit is controlled to select the second write mode when a charge level of the light emitting unit is less than a predetermined value. A program that causes a computer to execute a control method of an imaging apparatus including a read / write unit that reads / writes data from / to an external storage medium and a light-emitting unit that emits light to illuminate a subject,
A program comprising a control module for controlling the read / write means so as to interrupt the writing of data to the storage medium when the light emitting means emits light.   A computer-readable storage medium storing the program according to claim 13.

Images