JP2885246B2 - 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 conversion device configured and interposed and disposed 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) removably mountable in 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 such that various digital storage media having similar external shapes but completely different access speeds can be selectively connected to the same connection portion, so that the loaded storage media can be connected. Must be identified each time. [Problems to be Solved by the Invention] The above-mentioned conventional system has the following problems. There is a drawback that information cannot be transferred accurately at a required speed according to the access speed of various storage media having different access speeds loaded into the apparatus main body. An object of the present invention is to identify the type of a storage medium loaded in an apparatus main body by itself, and to accurately and easily transfer information to the storage medium at a required speed according to the identification result. It is an object of the present invention to provide a signal conversion device capable of real-time processing or asynchronous processing. [Means for Solving the Problems] The present invention has taken the following measures to solve the above problems and achieve the object. That is, in this type of electronic camera, a detachable card-shaped storage medium having an identification unit for holding identification information indicating the specification or the like as a recording medium therein, and a drive signal of a first drive signal generator are received. An imaging unit that photoelectrically converts an image of a subject to generate an image signal, and receives the first drive signal and converts the image signal into a first signal.
An A / D converter which performs sampling and analog / digital conversion at a frequency of the following, and controls writing of a digital signal from the A / D converter to the removable card-shaped storage medium at the first frequency. A first write control unit;
A first dedicated connection terminal for integrating the digital signal of the A / D converter and the output signal of the first write control unit and outputting the integrated signal to the removable card-shaped storage medium; and the A / D converter Buffer memory for storing digital signals from the memory, and writing control of the digital signals read from the buffer memory to the removable card-shaped storage medium at a second drive frequency lower than the first drive frequency. A second write control unit for integrating the digital signal read from the buffer memory with the output signal of the second write control unit and outputting the integrated signal to the removable card-shaped recording medium. Switching operation according to the identification information held in the identification section of the removable card-shaped storage medium, the first dedicated connection terminal or the second dedicated connection terminal. A selection switching circuit for selectively switching a child, when the first dedicated connection terminal is selected by the selection switching circuit, performs continuous shooting of an image, and the second dedicated connection terminal is selected by the selection switching circuit. When is selected, a single image is taken. [Action] By taking such a means, the following action is exhibited. When writing storage information to a storage medium, the speed at which input information is written can be accurately controlled in accordance with the type (specification, etc.) of the loaded storage medium, real-time processing or asynchronous processing can be performed, and It is possible to provide a signal conversion device that enables continuous shooting or single shooting of a signal. 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 card memory 2 as a storage medium is detachably mounted on an electronic still camera main body 1 as an apparatus main body. 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). 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 and converts the image signal to a first frequency.
It samples at 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 of the buffer memory 16 at the first frequency f1. The write control unit 18 controls the A / D converter 15 based on the memory drive signal s1 from the first drive signal generator 11.
A digital signal from the memory is controlled to be written at a first frequency to the card memory 2 via a RAM dedicated connection terminal 21 and a selection switching circuit 23. Read control unit 19
Is for reading and controlling the digital signal stored in the buffer memory 16 with the memory drive signal s2 from the second drive signal generator 12. Write control unit 20
Is for writing and controlling a digital signal read from the buffer memory 16 on the basis of the memory drive signal s2 to the card memory 2 via the ROM dedicated connection terminal 22 and the selection switching circuit 23. RAM dedicated connection terminal 21 is A / D
The digital signal from the converter 15 and the write control signal from the write control unit 18 are integrated and output to the point a of the selection switching circuit 23. The ROM dedicated connection terminal 22 integrates the digital signal from the buffer memory 16 and the write control signal from the write control unit 20 and outputs the integrated signal to the point b of the selection switching circuit 23. The card memory 2 is made of a storage medium having a different access speed, for example, a RAM or a ROM, and includes an identification unit 31. When the card memory 2 is loaded into the electronic still camera main body 1 and the card memory 2 is a RAM, the identification unit 31 supplies an identification signal “L” to the selection switching circuit 23 when the card memory 2 is a RAM.
In the case of a ROM, the identification signal “H” is applied to the selection switching circuit 2
3 to give. The selection switching circuit 23 performs a switching operation in accordance with the identification signal from the card memory 2, and selectively switches the RAM-only connection terminal 21 or the ROM-only connection terminal 22. 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 will be described. First frequency generated by first drive signal generator 11
When the imaging unit 13 is driven by the driving signal s1 of f1 (13.5 MHz), the image of the subject is photoelectrically converted by the imaging unit 13 to be an image 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. And A / D converter 15
The image signal is sampled by the first drive signal s1, converted from analog to digital, and supplied to the buffer memory 16, and the digital signal supplied to the buffer 16 is supplied to the buffer 16 by a control signal from the write control unit 17. Written in memory 16. On the other hand, when the card memory 2 is loaded into the electronic still camera main body 1, an identification signal is transmitted from the identification unit 31 of the card memory 2. For example, the currently loaded card memory 2 is RA
In the case of M, the identification signal “L” is given from the identification section 31 to the selection switching circuit 23. Then, the selection switching circuit 23
Switches to the side a shown by the solid line in the figure, and selects the RAM dedicated connection terminal 21. Therefore, 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 drive signal s1 from the first drive signal generator 11 via the RAM dedicated connection terminal 21 and the selection switching circuit 23. The data is written to the memory 2. Therefore, in this case, since the image signal from the imaging unit 13 is directly written into the card memory 2 by the writing control unit 18, the writing speed of the image signal to the card memory 2 is synchronized with the input system. As a result, in the first card memory 2, real-time processing can be realized,
Continuous shooting of images becomes possible. Next, when the card memory 2 is a ROM, when the card memory 2 is loaded into the electronic still camera main body 1, an identification signal “H” is given to the selection switching circuit 23 from the identification unit 31 of the card memory 2. . Then, the selection switching circuit 23 performs the switching operation to the b side indicated by the broken line in the figure, and the ROM dedicated connection terminal 22
Select Therefore, the digital signal stored in the buffer memory 16 is read by the read control unit 19 at the frequency f2 (0.5 MHz) drive signal s2 of the second drive signal generator 12, and written into the card memory 2 by the write control unit 20. . Therefore, since the frequency f1 of the drive signal s1 for writing to the buffer memory 16 and the drive signal s2 for reading are different, the drive signal s1 is asynchronous with respect to the input system, and only single shot of information is performed. As described above, according to the present embodiment, when the storage information is written into various storage media loaded into the apparatus main body 1, that is, the card memory 2, the type of the card memory 2, that is, the RAM or The ROM is identified, and the selection switching circuit 23 is switched by this identification signal to select the RAM dedicated connection terminal 21 or the ROM dedicated connection terminal 22, so that the card memory 2 is selected by the selected write control signal.
Is written to. Therefore, transfer to the card memory 2 is performed at a transfer speed corresponding to the type of the card memory 2 loaded in the electronic still camera body 1, for example, RAM or ROM, and accurate writing becomes possible. The circuit 23 simplifies the configuration. When the card memory 2 is a RAM, real-time processing becomes 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 from 11 is f1 (13.5 MHz) and the second
The frequency of the drive signal of the drive signal generator 12 is f2 (0.5 MHz)
However, any other frequency may be used as long as the frequency corresponds to the type of the card memory 2. 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, when writing storage information to a storage medium, the speed at which input information is written can be appropriately controlled according to the type (specification, etc.) of the loaded storage medium. Become. Therefore, even if various storage media having different access speeds are indiscriminately loaded into the main body of the apparatus, the writing and transferring speed of the information to the storage media is appropriate, and the configuration is simple. Irrespective of the type, writing can be performed accurately, real-time processing or asynchronous processing can be performed, and a signal conversion device that enables continuous shooting or single shooting of image signals can be provided.

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. DESCRIPTION OF SYMBOLS 1 ... Electronic still camera main body, 2 ... Card memory, 11 ... 1st drive signal generator, 12 ... 2nd drive signal generator, 13 ...
Imaging unit, 14 process unit, 15 A / D converter, 16 buffer memory, 17, 18, 20 write control unit, 19 read control unit, s1 first drive signal, s2 second Drive signal, 21… RA
M dedicated connection terminal, 22… ROM dedicated connection terminal, 23… selection switching circuit, 31… identification part.

Claims (1)

(57) [Claims] A detachable card-shaped storage medium having therein an identification section for holding identification information indicating specifications and the like as a recording medium; and a drive signal generator which receives a drive signal from a first drive signal generator, and operates to receive an image of a subject. An imaging unit that performs photoelectric conversion to generate an image signal; an A / D converter that receives the first drive signal, samples the image signal at a first frequency, and performs analog / digital conversion; A first write control unit for controlling the writing of the digital signal from the converter into the removable card-shaped storage medium at the first frequency; and the digital signal of the A / D converter and the first writing. A first dedicated connection terminal for integrating the output signal of the control unit and outputting the integrated signal to the removable card-shaped storage medium; a buffer memory for storing a digital signal from the A / D converter; Buffer memory La read digital signal to said detachable card-like storage medium, a second for writing control in the first second drive frequency lower than the drive frequency
A second dedicated connection terminal for integrating the digital signal read from the buffer memory and the output signal of the second write control unit and outputting the integrated signal to the removable card-shaped recording medium A switching operation for performing a switching operation in accordance with identification information held in the identification section of the removable card-shaped storage medium, and selectively switching the first dedicated connection terminal or the second dedicated connection terminal. A circuit for performing continuous shooting of an image when the first dedicated connection terminal is selected by the selection switching circuit, and a single image when the second dedicated connection terminal is selected by the selection switching circuit. An electronic camera characterized by taking pictures.