JP4155023B2 - Electronic camera, image processing method and program - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electronic camera, an image processing method, and a program.
[0002]
[Prior art]
Recently, a digital still camera (hereinafter referred to as “digital camera”) that obtains electronic data of an image by photographing and records it in a semiconductor memory is widely used in place of a camera using a silver salt film.
[0003]
Since this type of digital camera can perform various image processing on image data obtained by shooting relatively easily, it is possible to obtain white and black images and sepia-tone images even with color tone processing. By changing the setting, there are some that can obtain an image with strong redness, an image with strong blueness, and the like without a color filter.
[0004]
In addition, a technique has been considered in which a more natural or more vivid image can be obtained by performing the above-described color tone correction processing according to the subject. (For example, refer to Patent Document 1.)
[0005]
[Patent Document 1]
JP 2000-069496 A
[0006]
[Problems to be solved by the invention]
However, in all of the conventional digital cameras including the technique of the above-mentioned Patent Document 1, a user who takes a picture using the digital camera, for example, “red flower”, “person's skin”, “sunset”, “blue sky” By specifying the correction content by performing the selection operation corresponding to the subject, the camera side executes a color tone correction process corresponding to the specification.
[0007]
Accordingly, if the user does not select and specify the color tone correction processing content, or if the user makes a wrong selection and specification, it is natural that an image having the color tone desired by the user cannot be obtained.
[0008]
The present invention has been made in view of the above circumstances, and the object of the present invention is to make the color of the subject more vivid while simplifying the operations required for the user as much as possible. Another object of the present invention is to provide an electronic camera, an image processing method, and a program capable of obtaining a simple color image.
[0009]
[Means for Solving the Problems]
  According to the first aspect of the present invention, there is provided photographing means for taking a subject image as image data, determining means for determining a color component to be emphasized based on image data obtained by the photographing means, and color component determined by the determining means A color emphasizing unit that performs color emphasis processing on each pixel constituting the image data obtained by the photographing unit, and a recording unit that records the image data subjected to color emphasis processing by the color enhancement unit.In the electronic camera provided, the determining means determines whether or not color enhancement is performed based on a ratio of a ratio of the most used color component to a ratio of the second used color component in the image data. It is characterized by that.
[0010]
  With such a configuration, it is possible to obtain a more colorful color image corresponding to the color of the subject while simplifying the operations required for the user as much as possible.Furthermore, since whether or not to perform color enhancement is determined according to the ratio of the most used color component ratio to the second used color component ratio, it is unnatural due to excessive color enhancement. It can prevent becoming an image.
[0011]
  The invention of claim 2 is the invention of claim 1,The determining means determines to perform color enhancement processing when the ratio of the most used color component in the image data is greater than a ratio of the second used color component by a predetermined threshold or more. It is characterized by doing.
[0012]
  With such a configuration, in addition to the operation of the invention described in claim 1 above, color enhancement is performed only for color components that protrude to some extent from other color components.Can be done.
[0013]
According to a third aspect of the present invention, in the first aspect of the invention, the determining means divides the image data into a plurality of areas, automatically determines a color component to be emphasized for each of the divided areas, and determines the color. The emphasizing unit performs color emphasis processing on each pixel in the area based on the color component determined for each area by the determining unit.
[0014]
With such a configuration, in addition to the operation of the first aspect of the present invention, the image is divided and color enhancement is performed for each of a plurality of areas corresponding to the colors used. Even when there are a plurality of colors to be emphasized, such as an image of “green sea, blue sky, and white sandy beach”, a more colorful image can be obtained.
[0015]
According to a fourth aspect of the invention, in the first aspect of the invention, the determining means divides the image data into a plurality of areas and automatically selects a color component to be emphasized by a specific area among the divided areas. It is characterized by determining.
[0016]
With such a configuration, in addition to the operation of the first aspect of the present invention, in order to determine a color that emphasizes a specific area with priority, the color of the subject corresponding to the composition that is generally used The image can be more emphasized to make a colorful image.
[0017]
The invention according to claim 5 is the invention according to claim 4, wherein the specific area is located in the center of the image data.
[0018]
With such a configuration, in addition to the operation of the invention described in claim 4 above, the subject such as the portrait of a person, such as the portrait of a person, particularly the image of a general composition in which the subject is located in the center, It is possible to obtain an image in which the color of is more emphasized.
[0019]
The invention described in claim 6 further comprises display means for displaying an image obtained by the photographing means in the photographing ready state in the invention described in claim 1, wherein the determining means is in the photographing ready state. A color component to be emphasized is automatically determined from an image obtained by the photographing unit, and the color enhancement unit performs color enhancement processing on the image obtained by the photographing unit in a photographing preparation state based on the color component determined by the determining unit. And displaying on the display means.
[0020]
With such a configuration, in addition to the operation of the invention described in claim 1 above, it is possible to shift to shooting after visually recognizing an image that has been color-enhanced before performing shooting. By avoiding this, it is possible to capture an image as intended.
[0021]
  According to a seventh aspect of the present invention, a determination step for determining a color component to be enhanced based on given image data, and color enhancement for each pixel constituting the given image data based on the color component determined in the determination step A color emphasis process for performing processing, and a recording process for recording image data subjected to color emphasis processing in this color enhancement process.In the image processing method of the present invention, the determining step includes determining whether color enhancement is performed or not based on a ratio of a ratio of the most used color component to a ratio of the second used color component in the image data. It is characterized by doing.
[0022]
  With such a method, it is possible to obtain a more colorful color image corresponding to the color of the subject while simplifying the operations required for the user as much as possible.Furthermore, since whether or not to perform color enhancement is determined according to the ratio of the most used color component ratio to the second used color component ratio, it is unnatural due to excessive color enhancement. It can prevent becoming an image.
[0023]
  According to an eighth aspect of the present invention, a determination step for determining a color component to be enhanced based on given image data, and color enhancement for each pixel constituting the given image data based on the color component determined in the determination step A color emphasis step for performing processing, and a recording step for recording image data subjected to color emphasis processing in the color emphasis step;In the program for causing the computer to execute, the determination step includes whether or not the color enhancement is performed based on the ratio of the ratio of the most used color component to the ratio of the second used color component in the image data. It is characterized by determining.
[0024]
  With such program contents, it becomes possible to obtain a more colorful color image corresponding to the color of the subject while simplifying the operations required for the user as much as possible.Furthermore, since whether or not to perform color enhancement is determined according to the ratio of the most used color component ratio to the second used color component ratio, it is unnatural due to excessive color enhancement. It can prevent becoming an image.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
A first embodiment when the present invention is applied to a digital still camera will be described below with reference to the drawings.
[0026]
FIG. 1 is a perspective view showing an external configuration thereof. FIG. 1A is a perspective view mainly showing a front side configuration and FIG. 1B is mainly showing a rear side configuration.
[0027]
In this digital camera 1, a photographing lens 2, a self-timer lamp 3, an optical viewfinder window 4, and a strobe light emitting unit 5 are disposed on the front surface of a substantially rectangular thin plate body, and a power key 6 and a shutter key 7 are disposed on the upper surface. Arrange.
[0028]
The photographic lens 2 is, for example, a single focus lens and a fixed focus in order to be mounted on a thin body, and does not perform a zoom operation or a focus operation.
[0029]
The power key 6 is a key for turning on / off the power each time a pressing operation is performed. The shutter key 7 can be used as a key for instructing release in the shooting mode, and for setting / execution in menu selection or the like. It shall function.
[0030]
On the back of the digital camera 1, a mode switch (SW) 8, a menu key 9, a cross key 10, an optical viewfinder 11, a strobe charge lamp 12, and a display unit 13 are arranged.
[0031]
The mode switch 8 is constituted by a slide switch, for example, and switches between the photographing mode “R” and the reproduction mode “P”.
[0032]
The menu key 9 is operated when various menus are selected.
[0033]
The display unit 13 is composed of a color liquid crystal panel with a backlight, and performs monitor display as an electronic viewfinder in the photographing mode, while reproducing and displaying the selected image in the reproduction mode.
[0034]
Although not shown, a memory card slot with a lid is provided on the lower surface of the body, and a memory card as a recording medium of the digital camera 1 is detachably attached.
[0035]
Next, the electronic circuit configuration of the digital camera 1 will be described with reference to FIG.
In the monitoring state in the photographing mode, the CCD 23 which is an image pickup element disposed behind the photographing optical axis of the lens optical system 22 including the photographing lens 2 whose aperture position is moved by driving the motor (M) 21 is as follows. Scanned by a timing generator (TG) 24 and a vertical driver 25, a photoelectric conversion output corresponding to a light image formed at a fixed period is output for one screen.
[0036]
The photoelectric conversion output is appropriately gain-adjusted for each primary color component of RGB in the state of an analog value signal, then sampled and held by a sample hold circuit (S / H) 26, and digital data by an A / D converter 27 The color process circuit 28 performs color process processing including pixel interpolation processing and γ correction processing to generate a luminance signal Y and color difference signals Cb and Cr, and a DMA (Direct Memory Access) controller 29. Is output.
[0037]
The DMA controller 29 once uses the luminance signal Y and the color difference signals Cb and Cr output from the color process circuit 28 by using the composite synchronization signal, memory write enable signal, and clock signal from the color process circuit 28 once. And the DMA transfer to the DRAM 31 used as a buffer memory via the DRAM interface (I / F) 30.
[0038]
The control unit 32 includes a CPU, a ROM that fixedly stores an operation program executed by the CPU including a color enhancement process described later, a RAM used as a work memory, and the like, and controls the entire digital camera 1. It controls the operation. After the DMA transfer of the luminance and color difference signals to the DRAM 31 is completed, the luminance and color difference signals are read from the DRAM 31 via the DRAM interface 30 and written to the VRAM 34 via the VRAM controller 33.
[0039]
The digital video encoder 35 periodically reads out the luminance and color difference signals from the VRAM 34 via the VRAM controller 33, generates a video signal based on these data, and outputs the video signal to the display unit 13.
[0040]
As described above, the display unit 13 functions as a monitor display unit (electronic finder) in the shooting mode. By performing display based on the video signal from the digital video encoder 35, the display unit 13 receives from the VRAM controller 33 at that time. An image based on the stored image information is displayed in real time.
[0041]
When the shutter key 7 constituting the key input unit 36 is operated at a timing when still image shooting is desired in a state where an image at that time is displayed in real time as a monitor image on the display unit 13 as described above, a trigger signal is generated. Is generated.
[0042]
In response to this trigger signal, the control unit 32 immediately stops the path from the CCD 23 to the DRAM 31 immediately after the DMA transfer of the luminance and color difference signals for one screen captured from the CCD 23 to the DRAM 31 is completed. Transition to record save state.
[0043]
In this record storage state, the control unit 32 outputs the luminance and color difference signals for one frame written in the DRAM 31 through the DRAM interface 30 for each of Y, Cb, and Cr components of 8 pixels × 8 pixels horizontally. Are read in units called basic blocks of the data and written in a Joint Photographic Coding Experts Group (JPEG) circuit 37. The JPEG circuit 37 is an ADCT (Adaptive Discrete Cosine Transform), which is an entropy coding system. Data compression is performed by processing such as conversion.
[0044]
Then, the obtained code data is read out from the JPEG circuit 37 as a data file of one image, and a flash memory 38 which is a non-volatile memory enclosed in a memory card that is detachably mounted as a recording medium of the digital camera 1. Write to. Further, the flash memory 38 may be built in the digital camera 1 separately from the memory card.
[0045]
Then, along with the compression processing of the luminance and color difference signals for one frame and the completion of writing all the compressed data to the flash memory 38, the control unit 32 activates the path from the CCD 23 to the DRAM 31 again.
[0046]
The key input unit 36 includes the power key 6, the shutter key 7, the mode switch 8, the menu key 9, and the cross key 10 described above, and signals associated with these key operations are directly sent to the control unit 32. The
[0047]
In the playback mode, the control unit 32 selectively reads out the image data recorded in the flash memory 38, and decompresses the compressed image data in a procedure that is completely opposite to the procedure in which the data is compressed in the image shooting mode by the JPEG circuit 37. The decompressed image data is developed and stored in the VRAM 34 via the VRAM controller 33, and is periodically read out from the VRAM 34, and a video signal is generated based on the image data. Play and output.
[0048]
Next, the operation of the above embodiment will be described.
Here, the shutter key 7 of the key input unit 36 operates with a two-stage stroke, and the AE (automatic exposure) process is started in a first-stage operation state generally expressed as “half-press”. It is assumed that shooting is performed and shooting is performed in the second stage operation state in which the press operation is more strongly expressed, which is generally expressed as “full press”.
[0049]
FIG. 3 shows the processing content mainly based on an operation program executed by the control unit 32 in a state where the photographing mode is selected as the basic mode and the color enhancement mode is set by selection from the menu item. .
[0050]
At the beginning of the processing, the image picked up by the CCD 23 is sequentially held in the DRAM 31 which is a buffer memory as it is, and a through image display state is displayed on the display unit 13 (step A01), while the shutter key of the key input unit 36 is used. It is determined whether or not a half-press operation has been performed (step A02), and the process waits for a half-press operation of the shutter key 7 from the through image display state.
[0051]
Then, when the shutter key 7 is half-pressed, this is determined in step A02, and after the AE process is executed and the exposure value is locked (step A03), the shutter key 7 of the key input unit 36 is fully pressed. It is determined whether or not it has been operated (step A04), and if it has not been fully pressed, it is confirmed that the half-pressed state of the shutter key 7 is still maintained (step A05). This waits for the shutter key 7 to be fully pressed.
[0052]
If the half-press operation state of the shutter key 7 is released, this is determined in step A05, and the process returns to step A01 again.
[0053]
If the shutter key 7 is fully pressed, this is determined in step A04, and photographing is performed (step A06).
[0054]
The image data obtained by this photographing is once held and stored in the DRAM 31, and one pixel consisting of the luminance signal and the color difference signal is selected and read out (step A07), and converted into RGB primary color data by matrix calculation. One of the primary color components RGB having the highest gradation value is selected after conversion, and the count value is updated by “+1” to count the selected primary color component (step A08).
[0055]
Thereafter, it is determined whether or not the same counting process has been completed for all the pixels constituting the image data (step A09), and if not completed, the process returns to step A07.
[0056]
In this way, by repeatedly executing the processes of steps A07 to A09, the primary color component having the highest gradation value is selected and counted up for all the pixels constituting the image data.
[0057]
When it is determined that processing has been completed for all the pixels constituting one frame of image data, the primary color component with the highest count value is a predetermined ratio compared to the primary color component with the next highest count value. For example, the color component to be emphasized is determined by determining whether or not it is twice or more as a threshold value (step A10).
[0058]
For example, when the image is a photograph of “sunset” and the count value of the most primary color component R is more than twice the count value of the next most primary color component B, the image has a hue. In this respect, the color component R is mainly used, and it is determined that this should be emphasized.
[0059]
Therefore, it is determined whether or not there is a color component to be emphasized by the determination in step A10 (step A11), and only when it is determined that there is a color component, the processes of steps A12 to A14 are executed to perform actual color enhancement. To do.
[0060]
That is, first, one pixel consisting of a luminance signal and a color difference signal is selected and read out from the image data held and stored in the DRAM 31 (step A12), and the color component determined to be emphasized out of RGB is set to a predetermined ratio, for example, 3 The values of the luminance signal and the color difference signal are newly calculated by matrix calculation so as to be increased, and are updated and stored in the DRAM 31 so that the values are rewritten to the values subjected to color enhancement (step A13).
[0061]
Thereafter, it is determined whether or not the same color enhancement processing has been completed for all the pixels constituting the image data (step A14), and if not completed, the processing returns to step A12 again.
[0062]
In this way, by repeatedly executing the processing of steps A12 to A14, the color enhancement processing is performed on all the pixels constituting the image data. Step A15 is reached when it is determined in step A14 that the color enhancement processing has been completed for all the pixels constituting the image data for one frame.
[0063]
This step A15 is directly executed when it is determined in step A11 that there is no color component to be emphasized. The JPEG circuit 37 reads out the luminance and color difference signals for one frame written in the DRAM 31. (Step A15), the obtained code data is read out from the JPEG circuit 37 as an image data file for one frame, written into the flash memory 38 and recorded (step A16), The process is terminated, and the process returns to the process from step A01 for the next photographing again.
[0064]
As described above, since it is determined that the color component actually used in the image should be emphasized and the color enhancement process is performed, it is possible to simplify the operations required for the user of the digital camera 1 as much as possible. However, it is possible to obtain a more colorful color image corresponding to the color component of the subject.
[0065]
In the above embodiment, the threshold for determining the presence / absence of a color component to be emphasized is a predetermined ratio, for example, twice or more, compared to the count value of the color component with the next largest color component count value. However, the numerical value “2 times” itself may be arbitrarily variably set.
[0066]
In this way, by performing color enhancement only for color components that protrude to some extent from other color components to some extent, even for one pixel, color enhancement is performed for color components that have a larger count value than other color components. Therefore, it is possible to prevent an unnatural image from being excessively emphasized.
[0067]
(Second Embodiment)
A second embodiment when the present invention is applied to a digital still camera will be described below with reference to the drawings.
[0068]
The external configuration is basically the same as in FIG. 1 and the circuit configuration is the same as in FIG. 2, and in the following text, the same reference numerals are used for the same parts, and the illustration and explanation are given. Omitted.
[0069]
Next, the operation of the above embodiment will be described.
Here, the shutter key 7 of the key input unit 36 operates with a two-stage stroke, and in the first-stage operation state generally expressed as “half-press”, the AE (automatic exposure) process and other shooting operations are performed. It is assumed that shooting is performed in the second stage operation state in which the preparation is made and generally expressed as “full press” and the pressing operation is stronger.
[0070]
Further, in the present embodiment, as shown in FIG. 4, the image data for one frame obtained by photographing is equally divided into 3 × 3 horizontally, and a total of 9 areas from the upper left area 1 to the lower right area 9 are obtained. The color components to be emphasized are determined for each time.
[0071]
FIG. 5 shows the processing contents mainly based on an operation program executed by the control unit 32 in a state where the photographing mode is selected as the basic mode and the color enhancement mode is set by selection from the menu item. .
[0072]
At the beginning of the process, the image picked up by the CCD 23 is sequentially held in the DRAM 31 as a buffer memory as it is, and the through image display state in which the display unit 13 displays the monitor (step B01), the shutter key of the key input unit 36 is displayed. It is determined whether or not a half-press operation has been performed (step B02), and the process waits for a half-press operation of the shutter key 7 from the through image display state.
[0073]
Then, when the shutter key 7 is half-pressed, this is determined in step B02, and after the AE process is executed and the exposure value is locked (step B03), the shutter key 7 of the key input unit 36 is fully pressed. It is determined whether or not it has been operated (step B04), and if it has not been fully pressed, it is confirmed that the half-pressed state of the shutter key 7 is still maintained (step B05). This waits for the shutter key 7 to be fully pressed.
[0074]
If the half-pressed state of the shutter key 7 is released, this is determined in step B05, and the process returns to step B01 again.
[0075]
If the shutter key 7 is fully pressed, this is determined in step B04, and photographing is performed (step B06).
[0076]
The image data obtained by this photographing is once held and stored in the DRAM 31, and one pixel consisting of the luminance signal and the color difference signal is selected and read out (step B07), and converted into RGB primary color data by matrix calculation. One of the primary color components RGB having the highest gradation value is selected after conversion, and the count value is updated by “+1” as the selected primary color component is counted for each area (step B08).
[0077]
Thereafter, it is determined whether or not the same counting process has been completed for all the pixels constituting the image data (step B09). If not completed, the process returns to step B07 again.
[0078]
In this way, by repeatedly executing the processes of steps B07 to B09, the primary color component having the highest gradation value is selected for each area and counted up for all the pixels constituting the image data.
[0079]
When it is determined that processing has been completed for all pixels constituting one frame of image data, the primary color component with the highest count value is compared with the primary color component with the next highest count value for each area. Then, by determining whether or not a predetermined ratio, for example, twice or more, as a threshold value, the color component to be emphasized is determined for each area (step B10).
[0080]
This is because, for example, when the image in the area is “blue sky” and the count value of the most primary color component B is more than twice the count value of the next most primary color component G, The image is mainly composed of the color component B in terms of color tone, and it is determined that this should be emphasized.
[0081]
Accordingly, it is determined whether or not there is at least one area that needs to be color-enhanced based on the determination in Step B10 (Step B11). Only when it is determined that there is an area, Step B12 is performed to perform actual color enhancement. Processes B16 are executed.
[0082]
That is, after selecting one area for which it is necessary to perform color enhancement (step B12), one pixel composed of a luminance signal and a color difference signal is selected from the image data in the area held and stored in the DRAM 31. Select and read (step B13), and newly calculate the luminance signal and color difference signal values by matrix calculation to increase the color component determined to be emphasized out of RGB by a predetermined ratio, for example, 30%. By updating and storing the data in the DRAM 31, the value is rewritten to a value with color enhancement (step B14).
[0083]
Thereafter, it is determined whether or not the same color enhancement processing has been completed for all the pixels constituting the image data in the area (step B15). If not completed, the processing returns to step B13 again.
[0084]
In this way, by repeatedly executing the processing of steps B13 to B15, the color enhancement processing is performed on all the pixels constituting the image data in the area. Then, if it is determined in step B15 that the color enhancement processing has been completed for all the pixels constituting the image data in the area, whether or not the processing for all areas for which it is determined that color enhancement needs to be performed next has been completed. Is determined (step B16).
[0085]
If it is determined that there is still another area that needs to be color-enhanced, the process returns to step B12 to select the area, and the process from step B13 onward is repeated.
[0086]
A color enhancement process based on the determined color component is executed for every area where it is determined that color enhancement is necessary. Then, when processing of all the areas determined to require color enhancement is completed, this is determined in Step B16, and Step B17 is reached.
[0087]
This step B17 is directly executed when it is determined in step B11 that there is no area that needs to be color-enhanced, and the luminance and color difference signals for one frame written in the DRAM 31 are obtained. The data is read and compressed by the JPEG circuit 37 (step B17), and the obtained code data is read from the JPEG circuit 37 as an image data file for one frame, written in the flash memory 38, and recorded (step B18). Then, a series of processing relating to shooting is terminated, and the processing returns to the above-described step B01 for the next shooting again.
[0088]
In this way, color enhancement is performed for each of a plurality of areas obtained by equally dividing an image for one frame corresponding to the color used. Therefore, for example, in the case where there is an image of composition representing “emerald green sea” in areas 7 to 9 and “blue sky” in areas 1 to 6 of FIG. By setting a large gradation value of the color component G for the image, while setting a large gradation value of the color component B for the image in the same area 1 to area 6, the “emerald green sea” and “ The color of “blue sky” can be emphasized, and a more colorful image can be obtained.
[0089]
In FIG. 4, the image data of one frame has been described as being equally divided into a total of nine areas of 3 × 3 in the vertical direction. However, the number of divisions is not limited to this, and for example, 2 × vertical Various division patterns can be used, for example, when equally dividing into a total of 4 areas of 2 in width, equally dividing into a total of 6 areas of 2 x 3 in width, and equally dividing into 16 areas of 4 in 4 x 4 in width. Can think.
[0090]
(Third embodiment)
A third embodiment when the present invention is applied to a digital still camera will be described below with reference to the drawings.
[0091]
The external configuration is basically the same as in FIG. 1 and the circuit configuration is the same as in FIG. 2, and in the following text, the same reference numerals are used for the same parts, and the illustration and explanation are given. Omitted.
[0092]
Next, the operation of the above embodiment will be described.
Here, the shutter key 7 of the key input unit 36 operates with a two-stage stroke, and in the first-stage operation state generally expressed as “half-press”, the AE (automatic exposure) process and other shooting operations are performed. It is assumed that shooting is performed in the second stage operation state in which the preparation is made and generally expressed as “full press” and the pressing operation is stronger.
[0093]
FIG. 6 shows the processing contents mainly based on the operation program executed by the control unit 32 in a state where the photographing mode is selected as the basic mode and the color enhancement mode is set by selection from the menu item. .
[0094]
At the beginning of the processing, the image picked up by the CCD 23 is sequentially held in the DRAM 31 which is a buffer memory as it is and the through image display state in which the display is displayed on the display unit 13 (step C01), the shutter key of the key input unit 36 is performed. It is determined whether or not half of the shutter key 7 has been pressed halfway (step C02), and the process waits for the half-pressing of the shutter key 7 from the through image display state.
[0095]
Then, when the shutter key 7 is pressed halfway, this is determined in step C02, and after executing the AE process and locking the exposure value (step C03), the shutter key 7 of the key input unit 36 is fully pressed. It is determined whether or not it has been operated (step C04), and if it has not been fully pressed, it is confirmed that the half-pressed state of the shutter key 7 is still maintained (step C05). This waits for the shutter key 7 to be fully pressed.
[0096]
If the half-press operation state of the shutter key 7 is released, this is determined in step C05, and the process returns to step C01 again.
[0097]
If the shutter key 7 is fully pressed, this is determined in step C04, and photographing is performed (step C06).
[0098]
The image data obtained by this photographing is once held and stored in the DRAM 31, and one pixel consisting of the luminance signal and the color difference signal is selected and read out (step C07), and, for example, the three primary colors of the additive color method are obtained by matrix calculation. R, G, B, the three primary colors Y (yellow), Mg (magenta), Cy (cyan), and W (white: white) of the subtractive colors are converted into data and the one with the highest gradation value is selected. The selected color component is counted, and the count value is updated by “+1” (step C08).
[0099]
Thereafter, it is determined whether or not the same counting process has been completed for all the pixels constituting the image data (step C09). If not completed, the process returns to step C07 again.
[0100]
By repeatedly executing the processes in steps C07 to C09 in this way, the color component having the highest gradation value is selected and counted up for all the pixels constituting the image data.
[0101]
When it is determined that processing has been completed for all the pixels constituting one frame of image data, the color component having the highest count value is a predetermined ratio compared to the color component having the next highest count value. For example, a color component to be emphasized is determined by determining whether or not it is twice or more as a threshold (step C10).
[0102]
Accordingly, it is determined whether or not there is a color component to be emphasized by the determination in step C10 (step C11). Only when it is determined that there is a color component, the processes of steps C12 to C14 are executed to perform actual color enhancement. To do.
[0103]
That is, first, one pixel consisting of a luminance signal and a color difference signal is selected and read from the image data held and stored in the DRAM 31 (step C12), and the seven color components R, G, B, Y, Mg, Cy, By newly calculating values of the luminance signal and the color difference signal by matrix calculation so as to increase the color component determined to be emphasized in W by a predetermined ratio, for example, 30%, The value is rewritten to the emphasized value (step C13).
[0104]
Thereafter, it is determined whether or not the same color enhancement processing has been completed for all the pixels constituting the image data (step C14). If not completed, the processing returns to step C12 again.
[0105]
In this way, by repeatedly executing the processes of steps C12 to C14, the color enhancement process is performed on all the pixels constituting the image data. Step C15 is reached when it is determined in step C14 that the color enhancement processing has been completed for all the pixels constituting the image data for one frame.
[0106]
This step C15 is directly executed when it is determined in step C11 that there is no color component to be emphasized. The luminance and color difference signals for one frame written in the DRAM 31 are read out to read out the JPEG circuit 37. (Step C15), the obtained code data is read out from the JPEG circuit 37 as an image data file for one frame, written and recorded in the flash memory 38 (step C16), The process ends, and the process returns to the above-described step C01 for the next shooting again.
[0107]
In this way, as shown in the first embodiment, color enhancement is performed using not only the three primary colors RGB of the additive color method but also the three primary colors Y, Mg, and Cy of the subtractive color method and the mixed color W (white) that is not the primary color. Therefore, it is possible to select a color closer to the color frequently used in the image and emphasize it, and to reflect the intention of the user's color enhancement setting more faithfully in the image.
[0108]
The colors to be color-enhanced are not limited to the seven colors described above, but may be a color mixture corresponding to the subject or light source, such as skin color (person's skin) or orange (such as autumn leaves).
[0109]
(Fourth embodiment)
A fourth embodiment when the present invention is applied to a digital still camera will be described below with reference to the drawings.
[0110]
The external configuration is basically the same as in FIG. 1 and the circuit configuration is the same as in FIG. 2, and in the following text, the same reference numerals are used for the same parts, and the illustration and explanation are given. Omitted.
[0111]
Next, the operation of the above embodiment will be described.
Here, the shutter key 7 of the key input unit 36 operates with a two-stage stroke, and in the first-stage operation state generally expressed as “half-press”, the AE (automatic exposure) process and other shooting operations are performed. It is assumed that shooting is performed in the second stage operation state in which the preparation is made and generally expressed as “full press” and the pressing operation is stronger.
[0112]
In the present embodiment, as shown in FIG. 7, the color component to be emphasized is determined only by the central area A for one frame of image data obtained by photographing.
[0113]
FIG. 8 shows the processing contents mainly based on an operation program executed by the control unit 32 in a state where the photographing mode is selected as the basic mode and the color enhancement mode is set by selection from the menu item. .
[0114]
At the beginning of the processing, the image picked up by the CCD 23 is sequentially held in the DRAM 31 which is a buffer memory, and the display unit 13 displays the monitor on the through image display state (step D01), while the shutter key of the key input unit 36 is used. It is determined whether or not half of the shutter button 7 has been pressed halfway (step D02), and the process waits for the half-pressing operation of the shutter key 7 from the through image display state.
[0115]
Then, when the shutter key 7 is half-pressed, this is determined in step D02, and after performing the AE process to lock the exposure value (step D03), the shutter key 7 of the key input unit 36 is fully pressed. It is determined whether or not it has been operated (step D04), and if it has not been fully pressed, it is confirmed that the half-pressed state of the shutter key 7 is still maintained (step D05). This waits for the shutter key 7 to be fully pressed.
[0116]
If the half-press operation state of the shutter key 7 is released, this is determined in step D05, and the process returns to step D01 again.
[0117]
If the shutter key 7 is fully pressed, this is determined in step D04, and shooting is performed (step D06).
[0118]
The image data obtained by this photographing is once held and stored in the DRAM 31, and one pixel consisting of the luminance signal and the color difference signal located in the central area A is selected and read out from the image data (step D07). Then, the data is converted to RGB primary color data by matrix calculation, and one of the primary color components RGB having the highest gradation value is selected, and the selected primary color component is counted by area, and the count value is set to “+1”. "Update setting is made (step D08).
[0119]
Thereafter, it is determined whether or not the same counting process has been completed for all the pixels constituting the image data in the central area A (step D09). If not completed, the process returns to step D07 again.
[0120]
By repeatedly executing the processes of steps D07 to D09 in this way, the primary color component having the highest gradation value is selected for each area and counted up for all the pixels constituting the image data in the central area A.
[0121]
When it is determined that the processing for all the pixels constituting the image data in the central area A has been completed, the primary color component having the highest count value corresponding to all the pixels in the central area A is counted next. A color component to be emphasized is determined by determining whether a predetermined ratio, for example, twice or more of the primary color component having a high value is a threshold value (step D10).
[0122]
This is because, for example, in the image shown in the area, when the count value of the most primary color component is more than twice the count value of the next most primary color component, the image of that area is in terms of color tone. It is based on the most primary color components, and it is determined that this should be emphasized.
[0123]
Accordingly, it is determined whether or not there is a color component to be emphasized by the determination in step D10 (step D11). Only when it is determined that there is a color component, the processes of steps D12 to D14 are executed to perform actual color enhancement. To do.
[0124]
That is, first, one pixel consisting of a luminance signal and a color difference signal is selected and read out from the image data held and stored in the DRAM 31 (step D12), and a color component determined to be emphasized out of RGB is set to a predetermined ratio, for example, 3 The values of the luminance signal and the color difference signal are newly calculated by matrix calculation so as to be increased, and are updated and stored in the DRAM 31 to be rewritten to the values subjected to color enhancement (step D13).
[0125]
Thereafter, it is determined whether or not the same color enhancement processing has been completed for all the pixels constituting the image data (step D14), and if not completed, the processing returns to step D12 again.
[0126]
In this way, by repeatedly executing the processing of steps D12 to D14, color enhancement processing is performed on all the pixels constituting the image data. Then, when it is determined in step D14 that the color enhancement processing has been completed for all the pixels constituting the image data, the process proceeds to step D15.
[0127]
This step D15 is directly executed when it is determined in step D11 that it is not necessary to perform color enhancement. The luminance and color difference signals for one frame written in the DRAM 31 are read out to read out the JPEG circuit 37. (Step D15), the obtained code data is read out from the JPEG circuit 37 as an image data file for one frame, written in the flash memory 38 and recorded (step D16), The process is terminated, and the process returns to step D01 for the next shooting again.
[0128]
In this way, the entire image is color-enhanced corresponding to the color used in the central area A in the image for one frame. Therefore, an image utilizing the color tone of the subject located at the center can be obtained.
[0129]
In FIG. 7, the central area A is set for one frame of image data, and the processing shown in FIG. 8 is executed based on the central area A. However, the size and position of the area A are fixed. It is also possible to prepare a plurality of area patterns in advance, such as the left half, the right half, the upper half, the lower half, the lower left, etc., and select one by an arbitrary operation of the user, It is also conceivable that the position is set on the screen of the display unit 13 by operating the cross key 10 after selecting the size of the area.
[0130]
(Fifth embodiment)
A fourth embodiment when the present invention is applied to a digital still camera will be described below with reference to the drawings.
[0131]
The external configuration is basically the same as in FIG. 1 and the circuit configuration is the same as in FIG. 2, and in the following text, the same reference numerals are used for the same parts, and the illustration and explanation are given. Omitted.
[0132]
Next, the operation of the above embodiment will be described.
Here, the shutter key 7 of the key input unit 36 operates with a two-stage stroke, and in the first-stage operation state generally expressed as “half-press”, the AE (automatic exposure) process and other shooting operations are performed. It is assumed that shooting is performed in the second stage operation state in which the preparation is made and generally expressed as “full press” and the pressing operation is stronger.
[0133]
In the present embodiment, as shown in FIG. 9, the image data for one frame obtained by photographing is divided into the central area A and other peripheral areas S, and the colors to be emphasized for each area. Ingredients shall be determined.
[0134]
FIG. 10 shows processing contents mainly based on an operation program executed by the control unit 32 in a state where the photographing mode is selected as the basic mode and the color enhancement mode is set by selection from the menu item. .
[0135]
At the beginning of the process, the image picked up by the CCD 23 is sequentially held in the DRAM 31 which is a buffer memory as it is, and the through image display state in which the display unit 13 displays the monitor (step E01), the shutter key of the key input unit 36 is displayed. It is determined whether or not half of the shutter key 7 has been pressed halfway (step E02), and the process waits for the half-pressing operation of the shutter key 7 from the through image display state.
[0136]
Then, when the shutter key 7 is pressed halfway, this is determined in step E02, and after performing the AE process and locking the exposure value (step E03), the shutter key 7 of the key input unit 36 is fully pressed. It is determined whether or not it has been operated (step E04), and if it has not been fully pressed, it is confirmed that the half-pressed state of the shutter key 7 is still maintained (step E05). This waits for the shutter key 7 to be fully pressed.
[0137]
If the half-press operation state of the shutter key 7 is released, this is determined in step E05, and the process returns to step E01 again.
[0138]
If the shutter key 7 is fully pressed, this is determined in step E04, and shooting is performed (step E06).
[0139]
The image data obtained by this photographing is once held and stored in the DRAM 31, and one pixel consisting of the luminance signal and the color difference signal is selected and read out (step E07), and converted into RGB primary color data by matrix calculation. Select one of the primary color components RGB having the highest gradation value after conversion, and count the selected primary color component for each area of the central area A and the peripheral area S, and update the count value to “+1”. (Step E08).
[0140]
Thereafter, it is determined whether or not the same counting process has been completed for all the pixels constituting the image data (step E09), and if not completed, the process returns to step E07 again.
[0141]
By repeatedly executing the processing of steps E07 to E09 in this way, the primary color component having the highest gradation value is selected for each pixel of the central area A and the peripheral area S and counted up. .
[0142]
When it is determined that processing has been completed for all pixels constituting one frame of image data, the primary color component with the highest count value is compared with the primary color component with the next highest count value for each area. Then, by determining whether or not a predetermined ratio, for example, twice or more, as a threshold value, the color component to be emphasized is determined for each area (step E10).
[0143]
This is because, for example, when the image in the area is “blue sky” and the count value of the most primary color component B is more than twice the count value of the next most primary color component G, The image is mainly composed of the color component B in terms of color tone, and it is determined that this should be emphasized.
[0144]
Therefore, it is determined whether or not there is at least one area that needs to be color-enhanced by the determination in step E10 (step E11). Only when it is determined that there is an area, step E12 is performed to perform actual color enhancement. Processes E16 to E16 are executed.
[0145]
That is, after selecting the central area A or the peripheral area S for which it is determined that color emphasis needs to be performed (step E12), the image data in the area held and stored in the DRAM 31 is composed of a luminance signal and a color difference signal. One pixel is selected and read (step E13), and the values of the luminance signal and the color difference signal are newly calculated by matrix calculation to increase the color component determined to be emphasized out of RGB by a predetermined ratio, for example, 30%. This is updated and stored in the DRAM 31 to be rewritten to a value with color enhancement (step E14).
[0146]
Thereafter, it is determined whether or not the same color enhancement processing has been completed for all the pixels constituting the image data in the area (step E15). If not completed, the processing returns to step E13 again.
[0147]
In this way, by repeatedly executing the processes in steps E13 to E15, the color enhancement process is performed on all the pixels constituting the image data in the area. If it is determined in step E15 that the color enhancement processing has been completed for all the pixels constituting the image data in the area, whether or not the processing has been completed for all areas for which it is determined that color enhancement needs to be performed next. Is determined (step E12).
[0148]
If it is determined that there is an area that still needs to be color-enhanced, the process returns to step E12 to select the area, and the process from step E13 is repeated.
[0149]
In this way, color enhancement processing based on the determined color component is performed for each of at least one of the central area A and the peripheral area S that has been determined to require color enhancement. Then, when the processing of the area determined to require color enhancement is completed, this is determined in step E16, and step E17 is reached.
[0150]
This step E17 is directly executed when it is determined in step E11 that there is no area that needs to be color-enhanced, and the luminance and color difference signals for one frame written in the DRAM 31 are obtained. The data is read and compressed by the JPEG circuit 37 (step E17), and the obtained code data is read from the JPEG circuit 37 as an image data file for one frame, written in the flash memory 38 and recorded (step E18). Then, a series of processing relating to shooting is ended, and the processing returns to the processing from step E01 for the next shooting again.
[0151]
In this way, the image for one frame is divided into the central area A and the peripheral area S, and color enhancement is performed for each of these areas corresponding to the colors used frequently. Therefore, in image data with a composition in which the subject is located in the center, the center subject and the background are separately color-enhanced as necessary, so that the subject looks better and the background is also sharp. it can.
[0152]
In FIG. 9, the central area A and the other peripheral areas S are set for one frame of image data, and the processing shown in FIG. 10 is executed based on the central area A. And the size and position of the peripheral area S are not fixedly set, and a plurality of area patterns may be prepared in advance by user's arbitrary operation, and any one of them may be selected, and each of them corresponds to each balance. It is also conceivable that the position of one area is set on the screen of the display unit 13 by operating the cross key 10 after selecting the size of the area.
[0153]
In each of the first to fifth embodiments, the color component to be color-enhanced is determined based on the image data obtained by photographing. However, the present invention is not limited to this. Alternatively, in the AE lock state in which the shutter key 7 is half-pressed, the presence or absence of color enhancement and the content of the color component in the case of execution may be determined simultaneously to enter the lock state.
[0154]
In this case, if a through image appropriately subjected to color emphasis processing is displayed on the display unit 13 before shooting, the user can move to shooting and recording after visually recognizing the content on the display of the display unit 13. Therefore, it is possible to reduce shooting failures and perform shooting as intended. It should be noted that finally, after photographing, the color enhancement processing is performed again and recorded.
[0155]
In addition, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention.
[0156]
Furthermore, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, at least one of the issues described in the column of the problem to be solved by the invention can be solved, and is described in the column of the effect of the invention. In a case where at least one of the obtained effects can be obtained, a configuration in which this configuration requirement is deleted can be extracted as an invention.
[0157]
【The invention's effect】
  According to the first aspect of the present invention, it is possible to obtain a more colorful color image corresponding to the color of the subject while simplifying the operations required for the user as much as possible.Furthermore, since whether or not to perform color enhancement is determined according to the ratio of the most used color component ratio to the second used color component ratio, it is unnatural due to excessive color enhancement. It can prevent becoming an image.
[0158]
  According to the invention described in claim 2, in addition to the operation of the invention described in claim 1, color enhancement is performed only for a color component that protrudes to some extent from other color components.Can be done.
[0159]
According to the third aspect of the invention, in addition to the effect of the first aspect of the invention, the image is divided and color enhancement is performed for each of a plurality of areas corresponding to the colors used. Even when there are a plurality of colors to be desired, a more colorful image can be obtained correspondingly.
[0160]
According to the fourth aspect of the present invention, in addition to the effect of the first aspect of the invention, in order to determine a color that emphasizes a specific area with priority, the subject is generally used in accordance with a composition that is often used. The color of the image can be further emphasized to make a colorful image.
[0161]
According to the fifth aspect of the invention, in addition to the effect of the fourth aspect of the invention, the skin color of the person image in a general composition image in which the subject is located at the center, such as a portrait of a person, for example. For example, an image in which the color of the subject is more emphasized can be obtained.
[0162]
According to the sixth aspect of the invention, in addition to the effect of the first aspect of the invention, since it is possible to shift to photographing after visually recognizing the color-enhanced image before performing photographing, It is possible to avoid the failure and reliably capture the image as intended.
[0163]
  According to the seventh aspect of the invention, it is possible to obtain a more colorful color image corresponding to the color of the subject while simplifying the operations required for the user as much as possible.Furthermore, since whether or not to perform color enhancement is determined according to the ratio of the most used color component ratio to the second used color component ratio, it is unnatural due to excessive color enhancement. It can prevent becoming an image.
[0164]
  According to the eighth aspect of the invention, it is possible to obtain a more colorful color image corresponding to the color of the subject while simplifying operations required for the user as much as possible.Furthermore, since whether or not to perform color enhancement is determined according to the ratio of the most used color component ratio to the second used color component ratio, it is unnatural due to excessive color enhancement. It can prevent becoming an image.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an external configuration of a digital camera according to a first embodiment of the present invention.
FIG. 2 is an exemplary block diagram showing a circuit configuration according to the embodiment;
FIG. 3 is a flowchart showing processing details in a shooting mode according to the embodiment;
FIG. 4 is a diagram illustrating an area division state of an image according to a second embodiment of the present invention.
FIG. 5 is a flowchart showing processing contents in a shooting mode according to the embodiment;
FIG. 6 is a flowchart showing processing contents in a shooting mode according to the third embodiment of the present invention.
FIG. 7 is a diagram illustrating an area division state of an image according to a fourth embodiment of the invention.
FIG. 8 is a flowchart showing processing contents in a shooting mode according to the embodiment;
FIG. 9 is a diagram illustrating an area division state of an image according to a fifth embodiment of the invention.
FIG. 10 is a flowchart showing processing contents in a shooting mode according to the embodiment;
[Explanation of symbols]
1 ... Digital camera
2 ... Photography lens
3 ... Self-timer lamp
4 ... Optical finder window
5 ... Strobe light emitting part
6 ... Power key
7 ... Shutter key
8 ... Mode switch
9 ... Menu key
10 ... Cross key
11 ... Optical finder
12 ... Strobe charge lamp
13 ... Display section
21 ... Motor (M)
22 ... Lens optical system
23 ... CCD
24 ... Timing generator (TG)
25 ... Vertical driver
26. Sample hold circuit (S / H)
27 ... A / D converter
28 ... Color process circuit
29 ... DMA controller
30 ... DRAM interface (I / F)
31 ... DRAM
32 ... Control unit
33 ... VRAM controller
34 ... VRAM
35 ... Digital video encoder
36 ... Key input section
37 ... JPEG circuit
38 ... Flash memory
A ... Central area
S ... Surrounding area

Claims (8)

Photographing means for capturing a subject image as image data;
Determining means for determining a color component to be emphasized based on image data obtained by the photographing means;
A color enhancement unit that performs color enhancement processing on each pixel constituting the image data obtained by the photographing unit based on the color component determined by the determination unit;
In an electronic camera comprising recording means for recording image data subjected to color enhancement processing by this color enhancement means ,
The determination means includes determining whether or not to perform color enhancement based on a ratio of a ratio of the most used color component in the image data to a ratio of the second used color component. camera. The determining means determines to perform color enhancement processing when the ratio of the most used color component in the image data is greater than a ratio of the second used color component by a predetermined threshold or more. The electronic camera according to claim 1, wherein: The determining means divides the image data into a plurality of areas, automatically determines a color component to be emphasized for each divided area,
3. The electronic camera according to claim 1, wherein the color enhancement means performs color enhancement processing on each pixel in the area based on the color component determined for each area by the determination means. 3. The electronic camera according to claim 1, wherein the determining means divides the image data into a plurality of areas and automatically determines a color component to be emphasized by a specific area among the divided areas.   5. The electronic camera according to claim 4, wherein the specific area is located in the center of the image data. It further comprises a display means for displaying an image obtained by the photographing means in a photographing preparation state,
The determining unit automatically determines a color component to be emphasized from an image obtained by the shooting unit in a shooting preparation state,
The color enhancement means performs color enhancement processing on the image obtained by the photographing means in a photographing preparation state based on the color component determined by the determination means, and causes the display means to display the image. The electronic camera according to 1 or 2 . A determination step for determining a color component to be enhanced based on given image data;
A color enhancement step of performing color enhancement processing on each pixel constituting the image data given based on the color component determined in the determination step;
In an image processing method including a recording step of recording image data subjected to color enhancement processing in this color enhancement step ,
The determining step includes determining whether or not color enhancement is performed based on a ratio of a ratio of the most used color component to a second used color component in the image data. Processing method. A determining step for determining a color component to be enhanced based on given image data;
A color enhancement step of performing color enhancement processing on each pixel constituting the image data given based on the color component determined in the determination step;
A recording step for recording the image data subjected to the color enhancement processing in the color enhancement step;
In a program that causes a computer to execute
The determining step includes determining whether or not color enhancement is performed based on a ratio of a ratio of the most used color component to a second used color component in the image data. .

Images