JP3738654B2 - Digital camera - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a digital camera, and more particularly to a digital camera having a continuous shooting function that captures and records a plurality of images according to a recording instruction.
[0002]
[Prior art]
The digital camera repeatedly captures and displays images at a substantially constant period, and in response to recording instructions given by the user, captures an image for recording and records image data representing the image on a recording medium. To do. In some digital cameras, in addition to a single shooting function that performs image shooting, image data generation, and image data recording only once when a recording instruction is given, image data is acquired from image shooting when a recording instruction is given. Some cameras have a continuous shooting function for performing the process up to recording a plurality of times.
[0003]
In general, the imaging device is configured as a two-dimensional charge coupled device (CCD), and includes a vertical transfer register provided for each vertical column of photodiodes as pixels and a horizontal transfer register for output. Each pixel performs photoelectric conversion, accumulates electric charge as a signal representing one point of the image, and outputs the signal to a corresponding vertical transfer register. Each vertical transfer register transfers a signal output from the pixel to the horizontal transfer register. The horizontal transfer register is simultaneously supplied with the signal of the pixel column in the horizontal direction, and the signal of the image sensor is read out for each pixel column in the horizontal direction. The vertical transfer register and the horizontal transfer register are shielded from light.
[0004]
There are an interlace method and a progressive method for reading a signal from the image sensor. In the interlace method, reading of signals of odd-numbered pixel columns and reading of signals of even-numbered pixel columns are performed separately. A signal for one field having a coarse resolution is obtained by reading each time, and one frame of image data is generated by synthesizing the signals of two fields. In the progressive method, charges are read out in the order of pixel columns without being divided into odd and even columns. One frame of image data can be generated by one reading.
[0005]
[Problems to be solved by the invention]
Both interlaced and progressive methods have advantages and disadvantages. In the interlace method, each pixel holds a signal read for the second time while the first reading is performed, and thus the signal intensity changes as the photoelectric conversion progresses during this time. For this reason, in a digital camera that employs an interlace method, it is necessary to provide a shutter on the optical path of light incident on the image sensor, and to mechanically block the exposure of the image sensor after completion of shooting. In addition, in the interlace method, since the reading operation is performed twice, the time required for reading becomes long, and it is difficult to start the next shooting promptly. In particular, this is a major obstacle to shortening the shooting interval when using the continuous shooting function. However, by using the shutter, it is possible to provide a high-quality image without smear.
[0006]
In the progressive method in which the signal of the image sensor is read out once, it is only necessary to output a signal immediately from each pixel after the photoelectric conversion is completed. For this reason, a camera adopting the progressive method does not need to have a shutter and has a simple configuration. become. In addition, it is possible to read out signals at a rate of one column to a plurality of pixel columns, thereby shortening the time required for reading. In recent years, development of an image sensor having an extremely large number of pixels has progressed, and even when image data is generated using signals of a part of pixel columns, an image having a resolution suitable for shooting conditions can often be obtained. . However, since the shutter is not used, if there is a very bright part such as a light source in the object to be photographed, the light may wrap around the shielded vertical transfer register and smear may occur.
[0007]
In the conventional digital camera, the signal reading from the image sensor is fixed to the interlace method or the progressive method, and the features of both methods cannot be utilized. The present invention provides a digital camera that can make use of the features of both types according to shooting conditions, and in particular, a digital camera that can use both types according to whether or not to use the continuous shooting function. With the goal.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, an image pickup device in which pixels are two-dimensionally arranged is provided, a recording image is taken according to a given recording instruction, and image data representing the taken image is generated. A digital camera for recording on a recording medium, and when a recording instruction is given, a single shooting mode in which an image is photographed, image data is generated, and image data is recorded once, and a recording instruction is given In some cases, having a continuous shooting mode in which image shooting, image data generation, and image data recording are performed multiple times, in single shooting mode, signals are read from the image sensor in an interlaced manner to generate image data, In the continuous shooting mode, a signal is read from the image sensor in a progressive manner to generate image data.
[0009]
In the single shooting mode, it is possible to record high-quality image data by reading out signals in an interlaced manner. On the other hand, in the continuous shooting mode, the shooting interval can be shortened by reading the signal in a progressive manner.
[0010]
Here, a shutter may be provided on the optical path of the light received by the image sensor, and the exposure of the image sensor may be blocked by the shutter after taking an image only in the single shooting mode. In this way, it is possible to reliably improve the quality of images recorded in the single shooting mode, and in the continuous shooting mode, it is possible to avoid the delay caused by the operation of closing the shutter and to reliably shorten the shooting interval. Is possible.
[0011]
A shutter may be provided on the optical path of the light received by the image sensor, and the exposure of the image sensor may be blocked by the shutter after taking an image in both the single shooting mode and the continuous shooting mode. The quality of image data recorded in the continuous shooting mode as well as the single shooting mode can be improved.
[0012]
In continuous shooting mode, a signal is read from the image sensor at a rate of one pixel row to a plurality of pixel rows, and only a part of the read signal of each pixel row is used to obtain an image having the same angle of view as the captured image. It is preferable to generate image data to represent. By reading out signals at a rate of one pixel column to a plurality of pixel columns, the time required for readout can be greatly shortened, and the photographing interval can be further shortened. Further, image data representing the entire captured image is obtained, and the capacity of the recording medium necessary for recording the image data is reduced.
[0013]
In continuous shooting mode, a signal is read from the image sensor at a rate of one pixel row to a plurality of pixel rows, and interpolation processing is performed on the signal of the read pixel row, and image data representing an image having the same angle of view as the captured image You may make it produce | generate. Even in this case, the time required to read out the signal is greatly shortened, and the photographing interval can be further shortened. In addition, image data representing the entire captured image is obtained, and the resolution of the image is also increased.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a digital camera of the present invention will be described with reference to the drawings. The external appearance of the digital camera 1 of this embodiment is shown in FIGS. 1 to 3, and the outline of the circuit configuration is schematically shown in FIG. 1 is a front view of the digital camera 1, FIG. 2 is a rear view, and FIG. 3 is a top view.
[0020]
The digital camera 1 has a photographing lens 11 on the front surface and two display units 12 and 13 on the rear surface. A push button shutter switch 14, a rotary switch 15, and a push button switch 16 are provided on the upper surface. Although not shown, an insertion slot for mounting a memory card 18 (see FIG. 4) as a recording medium is provided on the bottom surface of the digital camera 1.
[0021]
As shown in FIG. 4, a stop 11 a that also serves as a shutter is provided at the pupil position of the photographic lens 11, and an imaging element 21 is disposed behind the photographic lens 11. The digital camera 1 captures an image by photoelectrically converting light from a subject to be transmitted that has passed through the photographing lens 11 into an electric charge by the image sensor 21, and processes the electric charge accumulated in the image sensor 21 by various circuits described later. Thus, image data representing the image is generated. The image represented by the generated image data is displayed on the display units 12 and 13, and the image data is recorded on the memory card 18 in accordance with a recording instruction given by operating the shutter switch 14. Images are captured and displayed repeatedly at a substantially constant period, for example, 1/30 seconds.
[0022]
One display unit 12 is composed of a large liquid crystal display (LCD). The user can observe the image displayed on the display unit 12 from a distance of several tens of centimeters or more. Hereinafter, the display unit 12 is also referred to as a monitor. The other display unit 13 includes a small LCD 13a, a convex lens 13b, and a reflection mirror 13c. The user can further enlarge and observe the displayed image by viewing the LCD 13a through the lens 13b and the mirror 13c from a distance of several centimeters or less. The lens 13b is an eyepiece. Hereinafter, the display unit 13 is also referred to as an electronic viewfinder or a fan finder.
[0023]
The user can set the composition while viewing the image displayed on the monitor 12 or the electronic viewfinder 13, and can confirm the in-focus state of the photographing lens 11 with respect to the photographing target. Each of the LCDs of the monitor 12 and the viewfinder 13 has 640 pixels in the horizontal (lateral) direction and 480 pixels in the vertical (vertical) direction.
[0024]
The image sensor 21 is an area sensor having 2560 pixels in the horizontal direction and 1920 pixels in the vertical direction. Each pixel is provided with a filter that selectively transmits red (R) light, green (G) light, or blue (B) light, and all the pixels are for R light, G light, and B light. It is classified into three types for light. These three types of pixels are arranged in a Bayer type (see FIG. 7).
[0025]
The circuit configuration of the digital camera 1 will be described with reference to FIG. The digital camera 1 includes a correlated double sampling (CDS) circuit 22 and an automatic gain control (AGC) circuit 23 that process charges output as an analog signal from the image sensor 21, and an A / D converter that converts the analog signal into a digital signal. 24. An image processing CPU 25 that processes digital signals to generate image data representing a photographed image, and an image memory 26 that the image processing CPU 25 uses for temporary storage are provided.
[0026]
The CDS circuit 22 reduces the noise of the analog signal output from the image sensor 21, and the AGC circuit 23 adjusts the level of all signals from the CDS circuit 22 by its gain. The A / D converter 24 converts the analog signal from the AGC circuit 23 into a 10-bit digital signal.
[0027]
The image processing CPU 25 performs pixel interpolation 25a, resolution conversion 25b, color balance adjustment 25c, and gamma correction 25d on the digitized signal to generate image data representing the photographed image. Further, the image data to be recorded in the memory card 18 is subjected to image compression 25e processing. The image processing CPU 25 first writes the digital signal from the A / D converter 24 into the image memory 26, and then reads out the signal from the image memory 26 and writes the signal into the image memory 26 while performing pixel interpolation 25a to image compression 25e. We will proceed with the process.
[0028]
The pixel interpolation 25a generates a signal missing at each pixel position of the image sensor 21 (for example, R and B signals at the G light pixel position) from signals of surrounding pixels. Thereby, three signals of R, G, and B are obtained corresponding to each pixel. For the G signal, the average value of the intermediate binary values of the four pixel signals is obtained, and for the R and B signals, the average value of the two pixel signals is obtained.
[0029]
In the resolution conversion 25b, a predetermined number of signals are extracted from the signal after pixel interpolation, or the signal after pixel interpolation is further subjected to interpolation processing to convert the resolution. Signal extraction and interpolation are performed in association with a method of reading a signal from the image sensor 21.
[0030]
The color balance adjustment 25c adjusts the intensity for each of the R, G, and B signal groups so as to achieve an appropriate white balance. Specifically, a portion that is originally white is estimated based on the intensity and distribution of the R, G, and B signals, and an average value for each of the R, G, and B signals is obtained for the portion, and G The intensity of each of the R, G, and B signals is corrected from the intensity ratio of / R and the intensity ratio of G / B.
[0031]
The gamma correction 25d performs non-linearization on the signal intensity so as to be compatible with an external device that uses image data via the monitor 12, the finder 13 or the memory card 18. The image compression 25e compresses image data by performing discrete cosine transform (DCT) and Huffman coding according to the JPEG method. It is also possible to read out the image data recorded in the memory card 18 and reproduce and display it on the monitor 12. In this case, the image processing CPU 25 performs a reverse process of the compression on the read out image data to obtain an image before compression. Play the data.
[0032]
In addition, the digital camera 1 includes a camera control CPU 31, an aperture driver 32, a sensor driver 33, a video encoder 34, and a card driver 35. The camera control CPU 31 controls the entire digital camera 1. The camera control CPU 31 is connected to the operation unit 36 including the above-described various switches including the shutter switch 14, and controls the operation of the digital camera 1 in accordance with a signal given from the operation unit 36. The aperture driver 32 drives the aperture 11 a that also functions as a shutter, and the sensor driver 33 generates a control signal indicating the output timing of the electric charge accumulated by the photoelectric conversion and gives it to the image sensor 21.
[0033]
In photographing until a recording instruction is given by the shutter switch 14, the aperture 11a is opened, and the exposure amount is controlled by adjusting the photoelectric conversion time (electronic shutter speed) of the image sensor 21. When a recording instruction is given, that is, when an image for recording is taken, the aperture of the diaphragm 11a and the photoelectric conversion time are set according to a predetermined relationship to control the exposure amount. The exposure amount is controlled based on the intensity of a signal from a partial area at the center of the image sensor 21.
[0034]
The video encoder 34 encodes the image data given from the image processing CPU 25 by the NTSC method or the PAL method, and outputs the encoded image data to the monitor 12 and the finder 13. The card driver 35 writes the image data given from the image processing CPU 25 to the memory card 18, reads the image data from the memory card 18, and gives it to the image processing CPU 25.
[0035]
When a recording instruction is given by operating the shutter switch 14, the digital camera 1 captures an image for recording, generates image data representing the captured image, and records the generated image data only once. Mode, and a continuous shooting mode in which from recording of a recording image to recording of image data is continuously performed a plurality of times when a recording instruction is given. The number of images shot in the continuous shooting mode is set to 3. Switching between the single shooting mode and the continuous shooting mode is performed by operating the switch 15.
[0036]
The digital camera 1 also has both an interlace method and a progressive method as a method for reading out charges (signals) from the image sensor 21. The readout method corresponds to the above-described mode, and signals are read out in the interlace method in the single shooting mode and in the progressive method in the continuous shooting mode.
[0037]
The digital camera 1 has a full mode and a half mode with respect to generation of image data representing an image for recording. In the full mode, image data having the same number of signals in the horizontal direction 2560 and the vertical direction 1920 as the number of pixels of the image sensor 21 is generated and recorded. The half mode is to generate and record image data having half the number of signals in both the horizontal direction and the vertical direction. In both the full mode and the half mode, the angle of view of the image represented by the image data is equal to the angle of view of the image captured by the image sensor 21.
[0038]
There is no restriction on the relationship between the single shooting mode and the continuous shooting mode and the full mode and the half mode, and the full mode and the half mode can be selected in either the single shooting mode or the continuous shooting mode. Each time the switch 16 is operated, the full mode and the half mode are switched, and the set mode is displayed on the monitor 12 and the finder 13.
[0039]
Image data representing an image used only for display has the same number of signals in the horizontal direction 640 and the vertical direction 480 as the number of pixels of the LCD of the monitor 12 and the finder 13. Further, readout of an image signal used only for display from the image sensor 21 is performed by a progressive method.
[0040]
The configuration of the image sensor 21 is schematically shown in FIG. The image sensor 21 includes a photodiode 21a as a pixel. As described above, the photodiodes 21a are arranged in 2560 in the horizontal direction and 1920 in the vertical direction. Each vertical column of photodiodes 21a is provided with a vertical transfer register 21b formed as a charge coupled device (CCD), and each photodiode 21a is a vertical transfer register for storing charges (signals) accumulated by photoelectric conversion. It outputs to the corresponding part of 21b.
[0041]
Each vertical transfer register 21b is connected to a horizontal transfer register 21c which is also formed as a CCD, and sequentially outputs a signal output from each photodiode 21a to a corresponding portion of the horizontal transfer register 21c. The horizontal transfer register 21c is connected to the amplifier 21d, and the output of the horizontal transfer register 21c is amplified by the amplifier 21d and supplied to the CDS circuit 22 (not shown). The vertical transfer register 21b and the horizontal transfer register 21c are shielded from light.
[0042]
Signal output from the photodiode 21a to the vertical transfer register 21b, signal transfer in the vertical transfer register 21b, and signal transfer in the horizontal transfer register 21c are performed by the control signal supplied from the sensor driver 33 as described above. Be controlled. On the other hand, the camera control CPU 31 controls the sensor driver 33 to output charges depending on whether the mode is the single shooting mode or the continuous shooting mode, and whether the mode is the full mode or the half mode. The transfer speed of the photodiode 21a to be moved, the vertical transfer register 21b, and the horizontal transfer register 21c is changed.
[0043]
Hereinafter, processing from reading of electric charges of the image sensor 21 to recording of image data on the memory card 18 or display of images on the monitor 12 and the viewfinder 13 will be described with specific examples. Among the codes used in each example, P1 represents a process of reading out charges from the image sensor 21, P2 represents a process of generating image data representing an image, and P3 represents a process of displaying an image on the monitor 12 or the viewfinder 13. Further, S1 represents electric charges accumulated in the image sensor 21, S2 represents a signal read and digitized in the process P1, and S3 represents a signal converted into image data representing an image in the process P2.
[0044]
The signal processing of the first example is shown in FIG. This example is processing until a recording instruction is given, that is, processing of a signal used only for display. In this example, the charge of the image sensor 21 is read at a rate of one pixel column to four pixel columns by the progressive method, and the thinning process in the vertical direction is performed. Further, when reading, the charges of pixels of the same color adjacent on the vertical transfer register 21b are added.
[0045]
FIG. 7 shows a pixel column from which charges are read. The charges of 4 pixel columns are read out every 16 pixel columns. Among these pixel columns, two pixel columns including G light pixels and R light pixels, G light pixels, and B light Two pixel columns including pixels for light are included. The charges of the two pixels for R light are added, the charges of the two pixels for B light are added, and the charges of the four pixels for G light are also added by two pixels. Eventually, the number of horizontal columns of the signal S2 after reading is 240. This reading process P1 can be performed at a speed eight times that for reading all the pixel columns in the horizontal direction individually.
[0046]
In the image data generation process P2, signals are extracted at a rate of one pixel per four pixels for each horizontal signal sequence, and the number of signals S3 is set to the horizontal direction 640 and the vertical direction 240. The number of signals in the horizontal direction coincides with the number of pixels in the horizontal direction of the LCD of the monitor 12 and the finder 13, and the number of signals in the vertical direction is half the number of pixels in the vertical direction of the LCD. Therefore, in the display process P3, each signal sequence in the horizontal direction is output twice. As a result, an image having an angle of view corresponding to the entire image sensor 21 is displayed on the entire monitor 12 and the finder 13.
[0047]
The signal processing of the second example is shown in FIG. This example is signal processing when a recording instruction is given in the single shooting mode and the full mode. In the reading process P1, the charges of all the pixel columns of the image sensor 21 are read out twice in an interlaced manner. FIG. 9 shows a pixel column from which charges are read. A signal for one field including G and R signals is obtained in the first reading, and a signal for one field including G and B signals is obtained in the second reading. The number of signals S2 in each field is 2560 in the horizontal direction and 960 in the vertical direction.
[0048]
FIG. 10 schematically shows a control signal given from the sensor driver 33 to the image sensor 21 when the signal is read and the open / closed state of the shutter 11a. SH represents the state of the shutter 11a. VD is a pulse for instructing the photodiode 21a to output charges. Here, the output command pulse VD is applied to every other row of photodiodes. VT is a pulse for instructing transfer to the vertical transfer register 21b. The head portion H of the transfer command pulse VT is for eliminating the charge on the vertical transfer register 21b, and has a period shorter than that of the portion that commands the transfer of the signal after the output command pulse VD is given. The output command pulse VD and the transfer command pulse VT are given twice, and the shutter 11a is closed over the entire period.
[0049]
In the image data generation process P2, the signals of each field are alternately arranged from the top row to obtain a signal S3 representing an image of one frame. This signal S3 reflects the resolution of the image sensor 21 as it is. The signal S3 is recorded on the memory card 18.
[0050]
The signal processing of the third example is shown in FIG. This example is signal processing when a recording instruction is given in the single shooting mode and the half mode. In the reading process P1, the charges of all the pixel columns of the image sensor 21 are read out twice in an interlaced manner. FIG. 12 shows a pixel column from which charges are read. At the time of reading, the charges of adjacent pixels of the same color on the vertical transfer register 21b are added. As a result, the transfer rate can be increased, and the time required for reading is about half that of the second example. The number of signals S2 in each field is 2560 in the horizontal direction and 480 in the vertical direction.
[0051]
In the image data generation process P2, the signals of each field are alternately arranged from the top row to obtain a signal S3 representing an image of one frame. However, instead of using all signals in each signal sequence, signals are extracted at a rate of one pixel per two pixels. As a result, the number of signals S3 becomes the horizontal direction 1280 and the vertical direction 960. The angle of view of the image represented by the signal S3 is the same as in the full mode. Although the resolution is about half, moire does not occur because adjacent signals of the same color are added during reading. The signal S3 is recorded on the memory card 18.
[0052]
The signal processing of the fourth example is shown in FIG. This example is signal processing when a recording instruction is given in the continuous shooting mode and the half mode. In the reading process P1, the charge of the image sensor 21 is read at a ratio of one pixel column to two pixel columns in a progressive manner. FIG. 14 shows a pixel column from which charges are read. Since the number of pixel columns from which charges are read is half that of all the pixel columns, the transfer rate can be increased and the time required for reading is short. The number of read signals S2 is 2560 in the horizontal direction and 960 in the vertical direction.
[0053]
In the image data generation process P2, a signal is extracted from each signal sequence of the signal S2 at a rate of one pixel per two pixels, and is set as a signal S3 representing an image. As a result, the number of signals S3 becomes the horizontal direction 1280 and the vertical direction 960. The angle of view of the image represented by the signal S3 is the same as in the full mode, but the resolution is halved. The signal S3 is recorded on the memory card 18.
[0054]
FIG. 15 schematically shows a control signal given to the image sensor 21 at the time of signal readout and the open / closed state of the shutter 11a. Here, the output command pulse VD is given to half of the photodiodes. The shutter 11a is closed over the entire period in which the charge output from the photodiode is on the vertical transfer register 21b. Thereby, an image without smear is obtained.
[0055]
As shown in FIG. 16, the reading may be performed without closing the shutter 11a. In this case, although smear may occur, it is not necessary to wait for the shutter to close, and the time required for reading can be shortened.
[0056]
The signal processing of the fifth example is shown in FIG. This example is signal processing when a recording instruction is given in continuous shooting mode and full mode. In the reading process P1, the charge of the image sensor 21 is read at a ratio of one pixel column to two pixel columns in a progressive manner. The pixel column from which charges are read out is the same as that shown in FIG. The number of read signals S2 is 2560 in the horizontal direction and 960 in the vertical direction.
[0057]
In the image data generation process P2, a vertical signal interpolation process is performed on the signal S2 to generate a new signal sequence, which is a signal S3 representing an image. As a result, the number of signals S3 becomes the horizontal direction 2560 and the vertical direction 1920. The signal S3 is recorded on the memory card 18. Although the resolution of the signal S3 is lower than that in the second example, since the interpolation process is performed, the signal S3 does not decrease to ½, unlike the case where the signal sequence is simply copied. Further, since the time required for the reading process P1 is short, the photographing interval can be shortened.
[0058]
In the camera of this embodiment, the number of images captured and recorded in the continuous shooting mode and the number of signals of image data to be recorded are constant, but these may be variable. Further, here, specific numerical values such as a pixel and a signal sequence to be read out are shown, but these are merely examples, and other values may be used. Although it is expected that an image sensor having more pixels will be developed in the future, the number of signals to be read and the number of signals included in image data may be determined according to the number of pixels of the image sensor.
[0059]
【The invention's effect】
Single shooting mode in which image shooting, image data generation, and image data recording are performed once when a recording instruction is given; image shooting, image data generation, and image when a recording instruction is given It has a continuous shooting mode in which data is recorded multiple times. In the single shooting mode, it reads out signals from the image sensor using the interlace method, and in continuous shooting mode, it reads out signals from the image sensor using the progressive method. In the digital camera of the present invention for generating image data, the purpose of the single shooting mode of shooting and recording a high-quality image and the purpose of the continuous shooting mode of shooting and recording a plurality of images at short time intervals Both of these can be fully achieved.
[0060]
If only the single-shot mode is used to block the exposure of the image sensor with the shutter after taking an image, the quality of the image recorded in the single-shot mode can be reliably increased, and the shutter is closed in the continuous-shot mode. The delay due to the operation can be avoided, and the photographing interval can be surely shortened.
[0061]
If the exposure of the image sensor is blocked by the shutter after taking an image in both the single shooting mode and the continuous shooting mode, the quality of the image data recorded not only in the single shooting mode but also in the continuous shooting mode may be improved. it can.
[0062]
In continuous shooting mode, an image representing an image having the same angle of view as the captured image is obtained by reading out signals from the image sensor at a rate of one pixel row to a plurality of pixel rows and using only a part of the read signals of each pixel row. When data is generated, the time required to read out the signal is greatly shortened, and the photographing interval can be further shortened. Further, image data representing the entire photographed image is obtained. In addition, the capacity of the recording medium necessary for recording the image data is reduced.
[0063]
In continuous shooting mode, a signal is read from the image sensor at a rate of one pixel row to a plurality of pixel rows, and interpolation processing is performed on the signal of the read pixel row, and image data representing an image having the same angle of view as the captured image is obtained. Even if it is generated, the time required to read out the signal is greatly shortened, and the imaging interval can be further shortened. Further, image data representing the entire captured image is obtained, and the resolution of the image is also increased.
[Brief description of the drawings]
FIG. 1 is a front view of a digital camera according to an embodiment of the present invention.
FIG. 2 is a rear view of the digital camera.
FIG. 3 is a top view of the digital camera.
FIG. 4 is a block diagram schematically showing an outline of a circuit configuration of the digital camera.
FIG. 5 is a diagram schematically illustrating a configuration of an image sensor of the digital camera.
FIG. 6 is a diagram showing a first example of signal processing of the digital camera.
FIG. 7 is a diagram showing a pixel arrangement of the image sensor and a pixel column read out in the first example.
FIG. 8 is a diagram showing a second example of signal processing of the digital camera.
FIG. 9 is a diagram showing a pixel row to be read in a second example.
FIG. 10 is a diagram schematically illustrating a control signal and a shutter state given to an image sensor in a reading process of a second example.
FIG. 11 is a diagram showing a third example of signal processing of the digital camera.
FIG. 12 is a diagram showing a pixel row to be read in a third example.
FIG. 13 is a diagram showing a fourth example of signal processing of the digital camera.
FIG. 14 is a diagram showing a pixel row to be read in a fourth example.
FIG. 15 is a diagram schematically illustrating a control signal and a shutter state given to an image sensor in a read process according to a fourth example.
FIG. 16 is a diagram schematically illustrating another state of a control signal and a shutter that are applied to an image sensor in a read process according to a fourth example.
FIG. 17 is a diagram showing a fifth example of signal processing of the digital camera.
[Explanation of symbols]
1 Digital camera
11 Shooting lens
11a Shutter / aperture
12 Monitor
13 Electronic viewfinder
13a LCD
13b eyepiece
14 Shutter switch
15, 16 switch
18 Memory card
21 Image sensor
21a photodiode
21b Vertical transfer register
21c Horizontal transfer register
22 CDS circuit
23 AGC circuit
24 A / D converter
25 Image processing CPU
25a Pixel interpolation processing
25b Resolution conversion processing
25c Color balance adjustment processing
25d Gamma correction processing
25e Image compression processing
26 Image memory
31 Camera control CPU
32 Aperture driver
33 Sensor driver
34 Video encoder
35 Card driver
36 Operation unit

Claims (5)

A digital camera that includes an image sensor in which pixels are arranged two-dimensionally, captures a recording image in accordance with a given recording instruction, generates image data representing the captured image, and records the image data on a recording medium. ,
A single shooting mode in which an image is shot, image data is generated, and image data is recorded once when a recording instruction is given, and an image is shot, image data is generated, and an image is shot when the recording instruction is given. With a continuous shooting mode that records data multiple times,
A digital camera characterized in that in the single shooting mode, signals are read from the image sensor by the interlace method to generate image data, and in the continuous shooting mode, signals are read from the image sensor by the progressive method to generate image data. A shutter is provided on the optical path of the light received by the image sensor,
2. The digital camera according to claim 1, wherein the exposure of the image sensor is blocked by a shutter after taking an image only in the single shooting mode. A shutter is provided on the optical path of the light received by the image sensor,
The digital camera according to claim 1, wherein exposure of the image sensor is blocked by a shutter after taking an image in both the single shooting mode and the continuous shooting mode.   In continuous shooting mode, an image representing an image with the same angle of view as the captured image is obtained by reading out signals from the image sensor at a ratio of one pixel column to a plurality of pixel columns and using only a part of the read signals of each pixel column. The digital camera according to claim 1, wherein data is generated. In continuous shooting mode, a signal is read from the image sensor at a rate of one pixel row to a plurality of pixel rows, and interpolation processing is performed on the signal of the read pixel row, and image data representing an image having the same angle of view as the captured image is obtained. The digital camera according to claim 1, wherein the digital camera is generated .

Images