JP3096869B2 - Still video camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a still video camera, and more particularly to an improvement in a recording / reproducing function.

[0002]

2. Description of the Related Art In recent years, instead of a conventional silver halide film camera, a light image from a subject is converted into an electric image signal by an image pickup device, and the electric image signal is converted into a magnetic disk corresponding to a conventional film or a removable disk. Still video cameras having a configuration for recording on a recording medium such as a simple card-type semiconductor memory (hereinafter referred to as an IC memory card) have been put into practical use (see Japanese Patent Application Laid-Open No. 59-183852). Still video cameras having a playback function have also been put to practical use.

[0003] On the other hand, when reproducing and displaying an image signal converted into a digital signal on a monitor, a system for performing image processing using a computer or the like has been generalized. Reproduction can be performed with the display magnification changed, such as displaying the entire image in reduced size.

[0004]

When recording an image signal in such a conventional still video camera, signal processing such as pre-processing is performed on an electric image signal photoelectrically converted by a photoelectric conversion element such as a CCD. In some cases, the speed at which the read image signal is converted into a digital signal and the speed at which the read image signal is written to a recording medium such as an IC memory card cannot be matched.

For example, since an IC memory card can be freely attached to and detached from a camera body, signals are transmitted and received via an electric section. However, since the electric section has a large contact resistance, the writing speed to the IC memory card is reduced. However, the reading speed may be slower than the reading speed, and the writing speed may also be delayed due to the compression / expansion processing when the read image signal is compressed / expanded and then written to the IC memory card. Would. Conversely, signal processing such as pre-processing and A / D conversion takes time, and the speed of reading from the signal processing unit may be slower than the speed of writing to the IC memory card. If the read speed and the write speed cannot be matched as described above, the image signal cannot be normally written to the IC memory card.

On the other hand, in the conventional still video camera with a reproducing function, a reproducing function attached to the camera has only a function of reproducing a recorded image signal at a display magnification as it is. It did not have the function to do it. Therefore, when performing playback by changing the display magnification, even if the still video camera has a playback function, the playback function cannot be used, and only by using an image processing system using a separate computer or the like. Was.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems. While ensuring the consistency between the reading speed and the writing speed at the time of recording by a still video camera, the recording operation can be properly performed. It is an object of the present invention to provide a still video camera capable of performing playback with a changed display magnification by enhancing a playback function attached to the camera.

[0008]

Therefore, a still video camera according to the present invention performs photoelectric conversion of a light image from a subject, and A / D converts an electric image signal converted by the photoelectric conversion means. A / D conversion means, a buffer memory for temporarily recording the digital image signal converted by the A / D conversion means, and recording for recording the digital image signal read from the buffer memory on a recording medium removable from the camera body. Means, recording / reproduction switching means for switching between recording and reproduction, display magnification instructing means for instructing display magnification during reproduction, and recording on the recording medium when the recording / reproduction switching means switches to reproduction. The digital image signal is processed to the display magnification designated by the display magnification instruction means and temporarily recorded in the buffer memory. Reproducing means for reproducing by reading at a rate adapted to the image signal recorded in the Ffamemori playback display speed, and configured to include.

[0009] The image processing apparatus may further include selection means for changing the display magnification and arbitrarily selecting an image portion to be reproduced. Further, the display magnification instructing means is constituted by an operation means having another function. After performing a switching operation to reproduction by the recording / reproducing means and an operation of selecting an image for changing the display magnification, the display magnification instructing means is operated. By switching to the instruction function, the display magnification instruction function may be obtained.

[0010]

According to the still video camera having the above construction, A
Since the digital information of the / D-converted image is temporarily stored in a buffer memory and then recorded on a recording medium such as an IC memory card, there is a difference between a reading speed from the signal processing unit and a writing speed to the recording medium. Even in such a case, good recording can be performed by reading the image signal through the buffer memory at a speed suitable for the writing speed of the recording medium.

Further, the image signal recorded on the recording medium is processed to the indicated display magnification and temporarily recorded in the buffer memory, and then read out at a speed suitable for the reproduction display speed. Reproduction can be performed by camera operation without using an external reproduction processing device. Further, a portion for changing the display magnification by providing a selecting means can be arbitrarily selected.

The display magnification instructing means, which is composed of operating means having other functions, is displayed by performing a switching operation to reproduction by the recording / reproducing means and an operation of selecting an image for changing the display magnification. By configuring so that the display magnification instructing function can be obtained only after switching to the magnification instructing function, the operation means is maintained in the photographing mode unless there is an intention to change the display magnification. In this case, the start of shooting can be hastened.

[0013]

Embodiments of the present invention will be described below. FIG. 1 is a block diagram showing the internal configuration of a still video camera according to the present invention. The still video camera according to the present embodiment has an IC memory detachable from a camera body as a storage medium for recording a captured image signal. In addition to using a card, it has a reproducing function of reproducing an image signal recorded on the IC memory card set in the camera body and outputting the reproduced image signal to the outside.

In FIG. 1, a light image from a subject is formed on a CCD 4 (photoelectric conversion means) via a lens 1, an aperture 2, and an optical filter 3. The CCD 4 photoelectrically converts the light image and outputs an electric image signal. The electric image signal is input to a pre-processing circuit 6 via a buffer 5 and is subjected to various processes by the pre-processing circuit 6.

The pre-processing circuit 6 comprises a double correlation sampling circuit (CDS circuit) 6a, a knee circuit 6b, an amplifier 6c, a clamp circuit 6d and the like. The output from the pre-processing circuit 6 is converted to a digital signal by an A / D converter 7 and converted by a conversion table 8 to γ correction,
After being subjected to white balance adjustment, it is output to the memory interface 9.

The digital image signal output to the memory interface 9 is temporarily stored in an image buffer memory 10, and is compressed and decompressed via a compression / decompression interface 11.
The compression processing is performed by the decompression processing circuit 12. The compressed image signal is sent to an IC via an IC memory card interface 13.
The data is sent to the memory card slot 14 and recorded on an IC memory card as a storage medium (not shown).

The image signal reproduced from the IC memory card proceeds in a direction opposite to the flow of the signal at the time of recording, is subjected to decompression processing by a compression / decompression processing circuit 12, and then passes through the memory interface 9. To the image reproducing circuit. The image reproducing circuit converts the sent digital image signal into an analog signal by the D / A converter 15,
After passing through the clamp circuit 16, the R, G, B
Are separated into three primary color signals.

The output of the color separation circuit 17 is supplied to an amplifier 18, L
LCD attached to camera body via CD drive circuit 19
It is output to a monitor (liquid crystal monitor) 20. Where 21 is L
A timing generating circuit for driving the CD is provided.
This is the backlight for the D monitor 20.
The high voltage generated by the high voltage generating circuit 23 is supplied to 22.

While the output of the color separation circuit 17 is output to the LCD monitor 20 as described above, it is also output to the post-processing circuit 24 for external output, and the video output from the post-processing circuit 24 is output. The signal can be supplied to an external monitoring device. The post-processing circuit 24 includes a matrix circuit 24a, an encoder circuit 24b, a video buffer 24c, and the like.

On the other hand, the control unit 25 for controlling various circuits includes a CPU 25a, a program memory 25b, a timing circuit 25c, and the like. The control unit 25 includes light metering data from a light metering circuit 26 to which the output of the pre-processing circuit 6 is input, light metering data from a light metering circuit 27, and a power supply / recording / playback switch function to be described later. Operation signals from the operation mode setting switch 67 and other various operation switches 28 are input.

The control unit 25 controls the CCD drive circuit 30 via a timing generation circuit 29, and further includes an aperture drive circuit 31, a strobe circuit 32, and an LCD display unit 33.
Control. Further, the control unit 25 controls a power supply control 34, and controls an AC adapter 35 or a battery 36.
Is supplied to a DC / DC converter 38 and a constant voltage circuit 39 via a power switch 37 to control the power supply to each block.

Further, in the still video camera of the present embodiment, various kinds of information are added to the reproduced image signal sent to the LCD monitor 20 attached to the camera and the video signal output to the outside via the post-processing circuit 24. A character generator 40 and a character generator memory 41 for combining and outputting are provided. FIG.
1 is a perspective view showing an external appearance example of a still video camera having the internal configuration shown in FIG. The microphone 1 and the microphone 52 are protected when not in use by closing the slide cover 53 in the direction A in the figure. Note that the slide cover 53 may be configured to also serve as a power switch.

On the upper surface of the camera body 49, a shutter switch 54 and an insertion slot 55 for an IC memory card are provided. The various operation switches 28 include a switch for selecting various modes, an up / down switch for instructing the number of frames of an image to be reproduced, an execution / cancel switch, and the like. The LCD display unit 33 showing the various modes is shown in FIG.
It is configured as shown in FIG.

Referring to FIG. 3, a double square frame at the upper left end has a segment display section for displaying various photographing modes and the state of consumption of the built-in battery and showing the number of frames of a reproduced image. Below the double square frame, a strobe switch 61,
A shooting mode changeover switch 62 is provided, a zoom setting switch 63, a multi-display changeover switch 64, and a frame erase switch 65 are provided immediately to the right of the double square frame, and a release switch 66 is further provided to the right, and a power supply is provided below. -An operation mode setting switch 67 is provided.

The operation of these switches will be described. First, the power is turned on by pressing the power / operation mode setting switch 67, and the operation mode is switched between the photographing mode and the reproduction mode by further pressing the switch. That is, the power supply / operation mode setting switch 67 and the circuit that performs the switching operation thereby constitute recording / reproduction switching means. When the mode is switched to the photographing mode, the desired mode in the double square frame is turned on by pressing the photographing mode changeover switch 62 to select it. Further, after switching to the flash photography mode by operating the flash switch 61, the photographing is performed by operating the release switch 66.

By this photographing, an image signal is recorded on the IC memory card detachably mounted on the camera body via the above-mentioned path. The image signal is read out from the CCD 4 and pre-processed, A / D converted, γ The image signal read from the image buffer memory 10 is subjected to compression / expansion processing to the IC memory via the IC memory card slot 14 at the read speed at which the image signal is read out from the image buffer memory 10 after correction, white balance adjustment, etc. The writing speed for recording on the card may be different. For example, the contact resistance of the IC memory card slot 14 or the compression / expansion processing
Image buffer memory for writing speed to C memory card
In some cases, the reading speed may be slower than the reading speed for reading data, or the reading speed may be slower due to the time required for signal processing. Even if the reading speed and the writing speed are different as described above, the image signal can be temporarily recorded in the image buffer memory 10 and then read at a speed suitable for the writing speed to the IC memory card.
Recording can be performed normally with consistency.

Next, the power / operation mode setting switch
Explaining the case where the mode is switched to the reproduction mode by the operation of 67, when the mode is switched to the reproduction mode, the release switch 66 functions as a frame feed switch, and the image of the frame corresponding to the number displayed in the segment is reproduced and displayed. Is done. When the mode is switched to the zoom mode by pressing the zoom setting switch 63 in the playback mode, the strobe switch 61 and the photographing mode switch 62 serve as a scroll switch, that is, a selection unit that can arbitrarily select an image portion to be zoomed. Function. For example, when the zoom setting switch 63 is pressed once, a portion to be zoomed is displayed as a frame as shown in FIG. 4, and the strobe switch 61 and the photographing mode switch 62 are used to move the display frame in the horizontal and vertical directions. After selecting the desired portion by moving to the above, pressing the zoom setting switch 63 again may display the selected portion in an enlarged manner. Further, the display magnification can be variably set by changing the size of the display frame by the pressing time of the first zoom setting switch 63. Here, if the original image has an M × N pixel size and the image of the portion to be enlarged is m × n,
In order to enlarge that part, it is necessary to interpolate the pixel of the difference. As an interpolation method, there are various methods such as using an average value of adjacent pixels. In the case of analog recording, image processing such as enlargement by interpolation is complicated because it is necessary to perform processing so as to match each line with the next line. It is easy to perform the data processing described above.

At the time of such zoom reproduction, the image signal from the IC memory card is subjected to a predetermined enlargement process and is recorded in the image buffer memory 10. If an image is read out from the image buffer memory 10 in accordance with the display speed of the processing circuit or the monitor 20, an enlarged image can be displayed. In this case, the enlargement processing is performed by controlling the compression / expansion interface 11 with the output from the control unit 25 in the zoom reproduction mode. Specifically, only the pixels of the enlarged portion set in the display frame are read out and written into the image buffer memory 10 while performing interpolation processing according to the display magnification (magnification magnification).

As described above, the mode is switched to the reproduction mode by operating the power / operation mode setting switch 67, and further, the image to be displayed by zooming is determined by operating the release switch 66, and then the strobe switch 61 and the photographing mode switching switch 62 are operated. Since the zoom setting can be set only after switching to the scroll switch function, the shooting is started when switching to the shooting mode in the middle of the playback mode as compared to the system that automatically switches to the playback mode and sets the zoom automatically. Can be hastened. In other words, when the user wants to switch to the shooting mode without intention to perform zoom playback display during playback, the flash switch 61 and the shooting mode switch 62 are held in the shooting mode function, so the shooting operation can be performed immediately. Since it is possible to start the operation, and to omit the time required for the other circuits to return from the zoom setting enabled state to the shooting enabled state, there is an advantage that the actual shooting operation can be started earlier.

[0030]

As described above, according to the present invention, the A / D-converted digital image signal is temporarily stored in the buffer memory and then recorded on the recording medium. Even if there is a difference between the reading speed of the recording medium and the writing speed to the recording medium, the image signal can be read through the buffer memory at a speed suitable for the writing speed of the recording medium, whereby good recording can be performed. .

Further, after the image signal recorded on the recording medium is processed to the indicated display magnification and temporarily recorded in the buffer memory, the display magnification is changed so that it can be read out at a speed suitable for the reproduction display speed. Reproduction can be performed by camera operation without using an external reproduction processing device. Further, if a selection unit is provided, a portion for changing the display magnification can be arbitrarily selected.

Further, after the operation for switching to reproduction and the operation for selecting an image for changing the display magnification are performed, the display magnification instructing function can be obtained only by switching to the display magnification instructing function. , The start of shooting when switching to the shooting mode can be hastened.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram of a still video camera according to an embodiment of the present invention.

FIG. 2 is a perspective view showing the front appearance of the still video camera.

FIG. 3 is a diagram showing switches and a periphery of a display unit.

FIG. 4 is a diagram showing an enlarged reproduction function in the still video camera;

[Explanation of symbols]

 1 Lens 4 CCD (Photoelectric Conversion Means) 10 Image Buffer Memory 24 Post Process Circuit 25 Control Unit 61 Strobe Switch 62 Shooting Mode Switch 63 Zoom Switch 67 Power / Operation Mode Setting Switch

──────────────────────────────────────────────────続 き Continued on the front page (72) Katsuya Nagaishi, Inventor 2970, Ishikawa-cho, Hachioji-shi, Tokyo Inside Konica Corporation (56) References JP-A-5-244566 (JP, A) JP-A 5-344408 (JP) , A) (58) Field surveyed (Int. Cl. ⁷ , DB name) H04N 5/907 H04N 5/91-5/956

Claims (3)

(57) [Claims] A photoelectric conversion unit for photoelectrically converting an optical image from a subject;
A / D conversion means for D-conversion, a buffer memory for temporarily recording the digital image signal converted by the A / D conversion means, and a digital image signal read from the buffer memory on a recording medium removable from the camera body. Recording means for recording; recording / reproduction switching means for switching between recording and reproduction; display magnification instruction means for instructing display magnification during reproduction; and recording when the recording / reproduction switching means switches to reproduction. The digital image signal recorded on the medium is processed to the display magnification instructed by the display magnification instructing means and temporarily recorded in the buffer memory, and the image signal recorded in the buffer memory is adapted to the reproduction display speed. A still video camera comprising: playback means for reading out at a speed for playback. 2. The still video camera according to claim 1, wherein said still video camera further comprises a selection unit which can arbitrarily select an image portion to be reproduced by changing said display magnification. 3. The display magnification instructing means is constituted by an operation means having another function, and is used after a switching operation to reproduction by the recording / reproducing means and an operation of selecting an image for changing the display magnification are performed. 3. The still video camera according to claim 1, wherein a function of indicating a display magnification is obtained by switching to a display magnification indicating function.