JP2681538B2 - Digital electronic still camera - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to image data of one frame captured in a memory.
The present invention relates to a digital electronic still camera including an image memory used for image processing for recording on a digital data recording medium such as a card.

Conventional technology and its problems The conventional digital electronic still camera captures a subject image using a solid-state electronic image sensor, and performs analog / digital conversion on the resulting still video signal, generation of luminance data and color data, Data is compressed and recorded on the memory card. However,
Whether the captured images are recorded in good condition,
It was not possible to immediately check whether or not the recording image quality at the set compression rate was good at the time of shooting. To check the quality of the captured image, remove the memory card from the camera,
It was very inconvenient because I had to attach it to a separately equipped playback device to play back.

BACKGROUND OF THE INVENTION Object of the Invention An object of the present invention is to provide a digital electronic still camera capable of immediately evaluating a captured image on the spot and indicating whether or not to record the image.

Another object of the present invention is to make it possible to evaluate whether or not the set compression ratio is appropriate for image data that has been decompressed after data compression.

Another object of the present invention is to make it possible to select an appropriate compression rate based on the evaluation of image data that has been expanded after data compression.

The configuration, action, and effect of the invention include a digital electronic still camera according to the present invention, which is obtained by capturing image data obtained by imaging and a digital camera.
Image memory for storing reproduced image data read from a data recording medium, display device for displaying captured image for image check and displaying reproduced image, captured image data stored in the image memory Image reading control means for reading out the image data and giving it to the display device so as to display a picked-up image, recording command input means operated when the picked-up image data should be recorded on the recording medium by image check judgment, and the recording command. In response to a recording command from the input means, recording control means for controlling the captured image data stored in the image memory to be recorded in the recording medium, and reproduction image data stored in the image memory. It is characterized in that a reproduction control means is provided for controlling the display device to display a reproduced image.

According to the present invention, the captured image data representing the subject image obtained by shooting is temporarily stored in the image memory. Then, the picked-up image data is read from the image memory, given to the display device, and the subject image is displayed. The captured image data is recorded on a recording medium such as a memory card only when a recording command is given from the recording command input means.

Since the captured image can be reproduced and displayed before the captured image data representing the captured subject image is recorded in a recording medium such as a memory card, the quality of the captured image can be evaluated. Only the recording medium can be recorded. Therefore, it is possible to avoid unnecessary image recording, and it is possible to perform efficient image recording.

When the image is reproduced, the reproduced image data read from the digital data recording medium is temporarily recorded in the image memory. The reproduced image data once stored in the image memory is given to the display device to display the reproduced image.

In this way, the display of the captured image for the image check performed before recording the captured image data on the recording medium and the display of the reproduced image represented by the reproduced image data read from the recording medium are displayed. It can be done by the device.

Generally, a digital electronic still camera is equipped with an image memory for storing captured image data. This image memory can be used to reproduce and display the captured image on the spot and to reproduce and display the reproduced image represented by the reproduced image data read from the recording medium, which complicates the structure of the camera. Nothing.

A digital electronic still camera according to the present invention is an image memory for temporarily storing image data for one frame that has been captured,
Data compression means for compressing the image data stored in the image memory, temporary storage means for temporarily holding the image data compressed by the data compression means, compressed by the data compression means and stored in the temporary storage means. Data decompression means for decompressing the held image data to original image data, display means for displaying an image represented by the image data decompressed by the data decompression means for image check, image data by image check judgment Recording command input means operated when recording is to be performed on a recording medium, and image data compressed by the data compression means and stored in the temporary storage means in response to an input command from the recording command input means. Recording control means for controlling the recording medium to be recorded on the recording medium. That.

The image data expanded by the data expansion means may be output from the camera and displayed on a monitor display device or the like separate from the camera.

According to this invention, the image data of the photographed subject image is
After the data is compressed, it is expanded again and displayed on the display device. Therefore, it is possible to immediately determine on the spot whether or not the proper compression has been performed by looking at the displayed image. If necessary, the compression rate can be changed and the quality of the compressed image quality can be evaluated with the changed compression rate. In this way, it is possible to record only the image data that is judged to have been appropriately compressed by actually seeing the image on the recording medium, and avoid recording unnecessary images and image data that has been improperly compressed. can do. Also in the present invention, since the image memory, the temporary storage means (buffer memory), the data compression means, the data decompression means and the like provided in the digital electronic still camera are used, the structure of the camera is complicated. There is no such thing.

Description of Embodiments FIG. 1 shows a first embodiment of the present invention, and is a block diagram showing an electrical configuration of a digital electronic still camera for recording image data representing a photographed subject image in a memory card. is there. Further, FIG. 2 shows a recording processing procedure of photographed image data by the CPU.

The overall operation of the digital electronic still camera 20 is CPU2
Is overseen by 1.

The digital electronic still camera 20 can reproduce and display the image data of the photographed subject on the viewfinder 16 for checking the image before recording it on the memory card 18. Therefore, the digital electronic still
The camera 20 includes a check mode switch 22. When the check mode switch 22 is pressed, the check mode operation of immediately displaying the photographed image on the viewfinder 16 is performed. The digital electronic still camera 20 has a recording mode switch.
23 is included, and only when the recording mode switch 23 is pressed, the image data representing the photographed subject image displayed on the viewfinder 16 is recorded on the memory card 18. A switch input signal indicating that these switches 22 and 23 are pressed is input to the CPU 21.
The viewfinder 16 is a kind of display device.

A still video signal representing a photographed subject image obtained from an image pickup optical system (not shown) including a CCD is input to an analog / digital conversion circuit 11, converted into a digital signal (image data), and output. This image data is input to the image memory 13 via the memory controller 10 and temporarily stored (step 31 in FIG. 2). The image memory 13 is a frame memory or a field memory.

The image data once stored in the image memory 13
Under the control of the control 10, the data is read out in the sequential scanning order, and if necessary, the field / frame conversion is performed.
Input to the luminance signal / color signal (Y / C) processing circuit 12. The luminance signal / color signal processing circuit 12 generates luminance (Y) data and color (C) data from the input image data (step 32). The luminance data and the color data are given again to the image memory 13 and stored therein.

When the check mode is set by the check mode switch 22 (YES in step 33),
The image data (Y / C data) stored again in the image memory 13 is given to the digital / analog conversion circuit 15 via the selector 14 controlled by the CPU 21. This image data is converted into an analog still video signal by the digital / analog conversion circuit 15 and given to the viewfinder 16. As a result, the photographed image is visually displayed on the viewfinder 16 immediately after the photographing (step 34).

The photographer directly knows the state of the photographed image such as the degree of image quality of the photographed image, image distortion, and desired composition by recording the image on the memory card 18 by visually observing the image displayed on the viewfinder 16. be able to. Therefore, the photographer can see the image reproduced on the viewfinder 16 and record only the desired image data on the memory card 18.

Stored in the image memory 13 (viewfinder 16
Image data (of the image displayed on the memory card)
When trying to record to 18, record mode switch 23
Is pressed (YES in step 35). This allows selector 1
When 4 is switched, the image data is read from the image memory 13 block by block (for example, 8 × 8 pixels at a time) and given to the data compression / expansion circuit 17. The data compression / decompression circuit 17 converts the input image data into DCT (Discrete
Cosine Transformation) Compresses by conversion processing.
As a result, the amount of image data for one frame decreases, and the number of frames that can be recorded on the memory card 18 increases. The data compressed image data is given to the memory card 18 and recorded (step 36).

The image displayed on the viewfinder 16 is not good,
If the photographer does not wish to record on the memory card 16, the photographer does not press the recording mode switch 23. Instead of this, a recording prohibition switch (not shown) may be provided and a recording prohibition command may be input by pressing this switch. If the recording mode switch 23 is not pressed (for example, for a predetermined time or longer) (NO in step 35), recording of the image data stored in the image memory 13 is prohibited, and the recording operation to the memory card 18 is not performed. Absent.

If the check mode switch 22 is not pressed and the check mode is not set (step 33
NO), the image data stored in the image memory 13 is
The process of displaying on the viewfinder 16 is not performed before recording on the memory card 18, and the image data after Y / C processing is immediately recorded on the memory card 18 (step 36).

After setting the check mode, the check mode may be canceled by pressing the switch 22 again. Alternatively, a normal mode switch may be provided and the check mode may be canceled when the normal mode switch is pressed. It may be done.

The digital electronic still camera 20 can also reproduce the image data recorded in the memory card 18. When the image data recorded in the memory card 18 is reproduced, the image data to be reproduced is given to the data compression / expansion circuit 17 and the compressed data is expanded. Then, it is stored in the image memory 13 via the selector 14 and the memory controller 10. Image memory 13
The image data stored in the image memory 13 is sequentially read from the image memory 13 and the selector 14 and the digital / analog conversion circuit 15 are read.
It is given to the viewfinder 16 via, and is reproduced and displayed.

3 and 4 show a second embodiment of the present invention. In these figures, the same parts and processes as those shown in FIGS. 3 and 4 are designated by the same reference numerals, and the description thereof will be omitted.

This digital electronic still camera has a compression ratio setting device.
24 are provided. The compression rate setting unit 24 sets the data compression rate in the image data compression processing performed by the data compression / expansion circuit 17, and sets and changes the compression rate such as 1/2, 1/4, 1/8. Is possible. Further, in this embodiment, an image memory 25 for displaying an image on the viewfinder 16 and a buffer memory 19 for temporarily storing the image data recorded on the memory card 18 are provided.

After the Y / C generation processing of the image data representing the photographed subject image (step 32 in FIG. 4), the compression rate set in the compression rate setting unit 24 is read by the CPU 21 and given to the data compression / expansion circuit 17. (Step 41). And
The image data after the Y / C generation processing which is once stored in the image memory 13 is sequentially read by the controller 10 and is given to the data compression / expansion circuit 17 through the selector 14 and the image is read at the compression rate previously read. Data compression processing is performed (step 42). The data compressed image data is temporarily stored in the buffer memory 19.

If the check mode is not set by the check mode switch 22, the compressed image data stored in the buffer memory 19 is stored in the memory card 18
Is recorded in (NO in step 33 and step 44).

If the check mode is set (YES in step 33), the compressed image data stored in the buffer memory 19 is expanded to the original image data by the data compression / expansion circuit 17, and the selector 14 And is stored in the image memory 25 (step 43). Then, the decompressed image data stored in the image memory 25 is used for display on the viewfinder 16 (step 34).

In this way, since the photographed image data is once compressed at the set compression rate and the compressed image data is decompressed and displayed, in addition to the determination as to whether or not the image is an appropriate image as in the above embodiment, Whether or not the set compression ratio is appropriate can be determined before recording on the memory card 18.

When the compression rate is not appropriate, the compression rate setting device 24 can be used to change the compression rate. When the compression rate is changed (YES in step 45), the process returns to step 41, the changed compression rate is read, and the image data is compressed at the changed compression rate. Are stored in the buffer memory 19 (steps 41 and 42). And
The image data is decompressed and then displayed on the viewfinder 16 (steps 43 and 34). This makes it possible to know whether the changed compression ratio is appropriate.
If necessary, the compression rate is changed as many times as necessary.

When the recording mode switch 23 is pressed, the data is compressed at the set or changed compression ratio and the buffer
Image data stored in the memory 19 is the memory card
It is recorded in 18 (steps 35 and 44).

If the recording mode switch 23 is not pressed for a certain period of time or more and the compression rate is not changed,
The compressed image data is not recorded on the memory card 18. The recording prohibition switch may be provided as in the above embodiment.

The image data expanded for display and temporarily stored in the image memory 25 may be D / A converted and then output from the output terminal 27 to the outside. In this case, the image represented by the expanded image data can be displayed on the external monitor display device 26. With such a configuration, the present invention can be applied to a camera that does not have a display device such as the viewfinder 16. Also, when the screen of the display device provided in the camera is small and difficult to see, the captured image can be evaluated in detail by displaying it on an external display device having a large screen.

[Brief description of the drawings]

1 and 2 show a first embodiment of the present invention. FIG. 1 is a block diagram showing the electrical configuration of a digital electronic still camera, and FIG. 2 is a CPU of the digital electronic still camera. 6 is a flowchart showing a procedure for recording a captured image by the. 3 and 4 show a second embodiment of the present invention. FIG. 3 is a block diagram showing the electrical configuration of a digital electronic still camera, and FIG. 4 is a flow chart showing the recording processing procedure. Is. 10 …… Memory controller, 13,25 …… Image memory, 16 …… Viewfinder, 18 …… Memory card, 19 …… Buffer memory, 20 …… Digital electronic still camera, 21 …… CPU, 22 Check mode switch, 23 recording mode switch, 24 compression ratio setting device, 26 monitor display device.

Front Page Continuation (72) Inventor Minoru Arai 2-26-30, Nishiazabu, Minato-ku, Tokyo Fuji Photo Film Co., Ltd. (72) Hiroshi Shimatani 2-26-30, Nishiazabu, Minato-ku, Tokyo Fuji Photo Film Co., Ltd. In-house (56) Reference JP-A-1-165267 (JP, A) JP-A-2-172364 (JP, A) Actual development Sho 62-117883 (JP, U)

Claims (7)

(57) [Claims] 1. An image memory for storing picked-up image data obtained by picking-up and reproduced image data read from a digital data recording medium, a picked-up image displayed for image checking, and a reproduced image displayed. Display device for displaying, image check control means for reading the picked-up image data stored in the image memory and giving the same to the display device, and displaying the picked-up image; Recording command input means operated when necessary, and recording control for controlling to record the captured image data stored in the image memory on the recording medium in response to the recording command from the recording command input means. Means and reproduced image data stored in the image memory is given to the display device to display the reproduced image. Digital electronic still camera provided with a regeneration control means, for cormorants control. 2. A check mode setting means is provided, and the image check control means displays a picked-up image on the display device when the check mode is set by the check mode setting means. The digital electronic still camera described in 1). 3. An image memory for temporarily storing image data of one frame taken, data compression means for compressing the image data stored in the image memory, and image data compressed by the data compression means temporarily. A temporary storage means for holding the image data, a data expansion means for expanding the image data compressed by the data compression means and held in the temporary storage means to the original image data, and an image data expanded by the data expansion means. Display means for displaying an image to be checked for an image, recording command input means operated when image data should be recorded on a recording medium by image check judgment, and in response to an input command from the recording command input means. The image data compressed by the data compression means and stored in the temporary recording means Recording control means for controlling to store the recording medium a digital electronic still camera, equipped with. 4. The check mode setting means, and when the check mode is set by the check mode setting means, the image data is expanded by the data expanding means and is expressed by the expanded image data. The digital electronic still camera according to claim 3, further comprising image check control means for controlling the display of the image by the display means. 5. An image memory for temporarily storing image data for one frame taken, data compression means for compressing the image data stored in the image memory, and image data compressed by the data compression means temporarily. A temporary storage means for holding the image data, a data expansion means for expanding the image data compressed by the data compression means and held in the temporary storage means to the original image data, and an image data expanded by the data expansion means. Output means for outputting an image to be checked for an image, recording command input means operated when image data should be recorded on a recording medium by image check judgment, and in response to an input command from the recording command input means. The image data compressed by the data compression means and stored in the temporary storage means Recording control means for recording the recording medium a digital electronic still camera, equipped with. 6. Check mode setting means, and when the check mode is set by the check mode setting means, the image data expansion processing by the data expansion means and the output of the expanded image data. 6. The digital electronic still camera according to claim 5, further comprising image check control means for controlling the output by the means. 7. A control means for controlling the data compression means so that when the compression rate is changed by the compression rate setting means, the image data stored in the image memory is compressed at the changed compression rate. The digital electronic still camera according to any one of claims (3) to (6), further comprising: