JP2653797B2 - Electronic camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is, for example, integrated with an electronic still camera or other device for generating stored information, or separate from the device for generating stored information. The present invention relates to a signal transfer device configured and interposed and arranged in a signal transmission path between the device main body and a storage medium (for example, a solid-state memory such as a card memory) detachably mountable to the device main body. In particular, the present invention relates to an apparatus for supporting various storage media having different specifications such as an access speed.

2. Description of the Related Art A camera adapted to transmit a signal corresponding to an optical image as stored information obtained by photoelectric conversion means to the outside via a buffer memory provided in the apparatus body is disclosed in, for example, Japanese Patent Application Laid-Open No. Sho 62-1987. It is already known in, for example, Japanese Patent No. 21310. This camera has a function of transferring a signal from the buffer memory to the external device at a transfer rate corresponding to a model of a connected external device such as a TV receiver, a VTR or a printer.

On the other hand, in recent years, the development of a system for converting stored information such as image information into a signal and storing it in a storage medium such as a so-called card memory which can be removably loaded into an apparatus body having a signal conversion function has been developed. I am doing it. This type of system is the same as the camera described in the above-mentioned publication in that information to be stored is transferred to and stored in externally connected storage means. However, this type of system is configured so that the image information is temporarily stored in a buffer memory in the apparatus main body, the information is read from the buffer memory, and stored in a card memory. Various digital storage media having completely different access speeds are selectively connected to the same connection section.

[Problems to be Solved by the Invention] The above-mentioned conventional system has the following problems. Since various storage media having different access speeds are loaded in the main body of the apparatus, for example, when a card memory such as a ROM capable of low-speed transfer is loaded, the transfer speed (input system) to the buffer memory and the transfer speed to the card memory are reduced. The transfer speed becomes asynchronous. For this reason, there has been a problem that real-time processing of an image signal cannot be performed and only a single image can be shot.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a signal transfer device capable of appropriately selecting information transfer to a storage medium loaded in a device main body, performing real-time processing or asynchronous processing, and enabling continuous shooting or single shooting of image signals. Is to provide.

[Means for Solving the Problems] The present invention has taken the following measures to solve the above problems and achieve the object. In other words, in this type of electronic camera, a plurality of removable card-shaped storage medium connectors and a high-speed removable card-shaped storage medium having a relatively high access speed that is acceptable to one of the plurality of removable card-shaped storage media connectors. A high-speed transfer means for transferring stored information at a relatively high transfer rate adapted to access the high-speed removable card-shaped storage medium when the plurality of removable card-shaped storage media are connected; When a low-speed removable card-shaped storage medium having a relatively low allowable access speed is connected to the other, the stored information is transferred at a relatively low transfer rate adapted to access the low-speed removable card-shaped storage medium. And a low-speed transfer means for providing the information.

[Action] By taking such a means, the following action is exhibited. It is possible to accurately control the speed at which input information is transferred according to the type (specification, etc.) of the applied storage medium, so that real-time processing or asynchronous processing of information can be performed, and continuous shooting or single shooting of information can be performed. Becomes possible.

Embodiment FIG. 1 is a diagram showing an embodiment in which the present invention is applied to an electronic still camera. In this electronic still camera, a first card memory 2 which is a storage medium capable of high-speed transfer is connected to an electronic still camera main body 1 which is an apparatus main body by a first connection unit 3.
The second card memory 4 which is removably mounted via a USB connection and which can be transferred at a low speed is configured to be removably mounted via a second connection unit 5.

The electronic still camera body 1 is configured as follows. The first drive signal generator 11 has a relatively high first frequency.
The memory drive signal s1 having f1 (13.5 MHz) is generated. The second drive signal generator 12 generates a memory drive signal s2 having a relatively low second frequency f2 (0.5 MHz).
Is to occur. The imaging unit 13 operates in response to the drive signal s1 of the first drive signal generator 11, photoelectrically converts an image of a subject, and provides an image signal to the process unit 14. The processing unit 14 receives an image signal from the imaging unit 13 and performs γ correction, white balance adjustment processing, and the like. The A / D converter 15 receives the drive signal s1 of the first drive signal generator 11, samples the image signal at a first frequency f1 (13.5 MHz), and performs analog / digital conversion. . The buffer memory 16 stores a digital signal from the A / D converter 15 in a memory area. The write controller 17 receives the memory drive signal s1 from the first drive signal generator 11 and controls the write operation of the buffer memory 16 at the first frequency. The write control unit 18 is provided with the first drive signal generator
The digital signal from the A / D converter 15 based on the memory driving signal s1 from the
Of the card memory 2 at the first frequency. The read control unit 19 receives the memory drive signal s2 from the second drive signal generator 12 and
The digital signal stored in the memory is read and controlled. The write control unit 20 outputs the memory drive signal s2
The digital signal read from the buffer memory 16 is controlled to be written into the second card memory 4 based on the above.

The first card memory 2 is a RAM capable of high-speed transfer, and is a storage medium that responds to the access speed of the first drive signal generator 11. The second card memory 4 is the RAM
Are storage media having different access speeds, for example, ROM, and are responsive to the access speed of the second drive signal generator 12. First connection part 3 and second connection part 5
Is provided on one side surface in the longitudinal direction of the electronic still camera main body 1, the first connection portion 3 is a connection terminal dedicated to a ROM to which the first card memory 2 is connected, and the second connection portion 5 is provided. Is a connection terminal dedicated to the ROM connected to the second card memory 4.

Next, the operation of the electronic still camera according to the present embodiment thus configured will be described. First, an operation when an image signal obtained by the imaging unit 13 is written to the buffer memory 16 and the first card memory 2 will be described. When the imaging unit 13 is driven by the driving signal s1 of the first frequency f1 (13.5 MHz) generated by the first driving signal generator 11, the image of the subject is photoelectrically converted by the imaging unit 13 and the image is formed. Signal. This image signal is γ-corrected in the processing unit 14, subjected to signal processing such as white balance adjustment, and then output to the A / D converter 15. Then, in the A / D converter 15, the image signal is sampled by the first drive signal s1,
The digital signal is supplied to the buffer memory 16 after being converted into a digital signal. The digital signal supplied to the buffer memory 16 is written into the buffer memory 16 by a control signal from the write control unit 17.

On the other hand, the digital signal from the A / D converter 15 receives the drive signal s1 from the first drive signal generator 11 according to the control signal of the write control unit 18 and receives the first card via the first connection unit 3. The data is written to the memory 2. Therefore, since the image signal from the imaging unit 13 is directly written to the first card memory 2 by the writing control unit 18, the writing speed of the image signal to the first card memory 2 is synchronized with the input system.
As a result, in the first card memory 2, real-time processing can be realized, and continuous shooting of images becomes possible.

Next, the operation of reading the storage medium (digital signal) stored in the buffer memory 16 and writing it to the card memory 4 will be described. First, the read control unit 19 and the write control unit 20 are supplied with the frequency f2 (0.5 MHz) drive signal s2 of the second drive signal generator 12. Therefore, the stored information stored in the buffer memory 16 is read out at the frequency f2 (0.5 MHz) of the second drive signal generator 12 and written into the card memory 4. Accordingly, since the frequency f1 of the drive signal s1 for writing to the buffer memory 16 is different from the drive signal s2 for reading, the data is asynchronous with respect to the input system, and only single shooting is performed.

As described above, according to the present embodiment, when transferring an image signal to the first card memory 2 having a relatively high access speed, the first drive signal generator 11 corresponding to the access speed of the first card memory 2 is used. Is written to the second card memory 4 via the first connection unit 3 by the write control unit 18 receiving the drive signal s1. When transferring an image signal to the second card memory 4 having a relatively low access speed,
The write control unit 20 which receives the drive signal s2 of the second drive signal generator 12 corresponding to the access speed of the second card memory 4.
Is written to the second card memory 4 via the second connection unit 5.

Therefore, it is possible to select an appropriate information transfer unit in accordance with the type of storage medium loaded in the apparatus main body 1. In the case of the first card memory 2, real-time processing of image signals can be performed. Continuous shooting is possible, and in the case of the second card memory 4, since asynchronous processing of image signals can be performed, only single shooting is possible.

Note that the present invention is not limited to the above-described embodiment. For example, in the above-described embodiment, the first drive signal generator
The frequency of the drive signal s1 from 11 is f1 (13.5 MHz), and the frequency of the drive signal s2 of the second drive signal generator 12 is f2 (0.5 M
Hz), but any other frequency may be used as long as the frequency corresponds to the type of the second card memory 4. Although the case where the second drive signal generator 12 is a single one has been illustrated, a plurality of generators that generate drive signals of different frequencies may be provided in parallel. In addition, it goes without saying that various modifications can be made without departing from the spirit of the present invention.

[Effects of the Invention] According to the present invention, it is possible to accurately control the speed at which input information is transferred in accordance with the type (specification, etc.) of an applied storage medium, and to perform real-time processing or asynchronous transfer of information. It is possible to provide a signal transfer device which can be performed by processing and enables continuous shooting or single shooting of an image signal.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an embodiment in which the present invention is applied to an electronic still camera. 1 ... Electronic still camera body, 2 ... First card memory, 3 ... First connection part, 4 ... Second card memory,
5 ... second connection part, 11 ... first drive signal generator, 12
... A second drive signal generator, 13... An imaging unit, 14... A process unit, 15... An A / D converter, 16.
18, 20 Write control unit, 19 Read control unit, s1
Driving signal, s2 ... Driving signal.

Claims (1)

(57) [Claims] 1. A high-speed detachable card-shaped storage medium, which has a relatively high access speed, is connected to one of the plurality of detachable card-shaped storage medium connections and one of the plurality of detachable card-shaped storage medium connections. A high-speed transfer means for transferring information to be stored at a relatively high transfer rate suitable for accessing the high-speed removable card-shaped storage medium; Low-speed transfer for transferring information to be stored at a relatively low transfer rate suitable for accessing the low-speed removable card-shaped storage medium when a low-speed removable card-shaped storage medium with a relatively low access speed is connected. An electronic camera, comprising: a unit;