TWI394439B - A digital still camera with previewing function by picture in picture and method thereof - Google Patents

Description

Digital camera and method for previewing images of interest using picture

The present invention relates to a digital camera with a preview function and a method for previewing an image of interest using a sub-picture, and more particularly to a digital camera using a sub-picture as a video preview and a method for previewing the same.

The first figure is a block diagram of a pre-view system circuit of a TFT-LCD used by a conventional digital camera. Referring to the first figure, the object image 105 is optically converted into a series of voltage signals 115 by the imaging device 110 in a scanning manner, and the voltage signal 115 is separated into three primary color signals 125 by a Color Filter Array (CFA) 120. The ambient illumination at the time of shooting may be too bright or too dark, or the color of the object may be deviated due to the difference in light source (such as sunlight, tungsten light, fluorescent light, etc.), and a white balance must be made for the light source. Correction (White Balance). Therefore, the three primary color signals 125 are transmitted to the white balance circuit 130, and the image signal 135 is generated after the white balance correction is completed.

Depending on the type of the photographing device 110, the color signals obtained after the same object is captured are different, so color correction is required for the characteristics of the photographing device 110. The image signal 135 is then sent to the color correction circuit 140 to adjust its color representation, and then the image signal 145 is generated. In addition, the voltage generated by the photosensitive pixels in the photographing device 110 and the light transmission performance of the TFT-LCD 190 are not in a linear relationship. In order for the brightness performance of the shot to be properly stored and displayed in the TFT-LCD 190, the image signal 145 must be subjected to Gamma Correction. Therefore, the image signal 145 is sent to the gamma correction circuit 150 to obtain the corrected image signal 155.

Then, the corrected image signal 155 must be subjected to a color space transform, and the input images respectively represent red (R), green (G), and blue (B). The three primary colors are converted into luminance and chrominance, and the separated modes are Y, Cb, and Cr; wherein Y represents luminance, and Cb and Cr represent chroma. The main purpose of converting to brightness and chroma mode is because the human eye is more sensitive to brightness than chroma. Then, the image signal 155 is converted into Y, Cb, and Cr by the color conversion circuit 160 through the color conversion circuit 160 to obtain an image signal 165.

Thereafter, the image signal 165 utilizes an edge enhancement 170 to make the image signal 165 sharper and sharper to produce the image signal 175. At this time, the image size of the image signal 175 depends on the photographing device 110, and the size may be different from the image size that the TFT-LCD 190 can display. In order to display the complete image in the TFT-LCD 190, the image signal 175 must be mathematically adjusted in resolution, so the image signal 175 is adjusted using a 2-D Image Scalar 180 to obtain an image signal. 185. Finally, the image signal 185 is directed to the color TFT-LCD 190 and the image signal 185 is correctly displayed.

It can be seen from the above that the pre-view system of the conventional digital camera can only provide a preview of the effect of a single image, and cannot provide a preview of the effect of other images of the user, so as to achieve direct viewing comparison of the picture effect. Therefore, the conventional digital camera cannot provide a user who generally has no photography concept, and intuitively selects an appropriate picture for shooting.

In view of the above, the present invention provides a digital camera with a preview function and a method for pre-viewing an image of interest using a sub-screen, and more particularly, a digital camera using a sub-picture as an image preview, which can be used for LCD preview (Live- In view/preview, the picture in the sub-picture (Picture in picture) is used to view the effect of adding or subtracting the exposure value (EV), white balance or contrast in the sub-picture, so that the user can more intuitively select the appropriate shooting image.

The digital camera with the pre-view function of the present invention comprises: a lens, a charge coupled unit, an exposure value calculation processing unit, a white balance/contrast calculation processing unit, a liquid crystal display panel, a sub-image processing unit, and a Memory unit and one control Buttons. The lens is used to capture an optical image. The charge coupled unit is coupled to the lens for converting the optical image into a digital image. The exposure value calculation processing unit is coupled to the charge coupled unit for calculating an exposure value of the digital image and generating a digital image of the at least one different exposure value different from the exposure value. The white balance/contrast calculation processing unit is coupled to the charge coupled unit for calculating the white balance/contrast of the digital image and generating a digital image of at least one different white balance/contrast different from the white balance/contrast. The image processing unit is coupled to the charge coupling unit, the exposure value calculation processing unit, the white balance/contrast calculation processing unit, and the liquid crystal display panel. The image processing unit displays the digital image on the mother of the liquid crystal display panel. The screen, and the digital image of the different exposure value or the digital image of the different white balance/contrast are displayed on the sub-picture of the liquid crystal display panel for at least one user to preview. At the same time, the memory unit is coupled to the image processing unit for storing the digital image, the digital image of the different exposure value, and the digital image of the different white balance/contrast. The control button is coupled to the image processing unit for controlling the selection of various menu items by the image processing unit.

The present invention provides a method for pre-viewing an image of interest using a sub-picture, which is suitable for a preview mode of a digital camera, and the steps include: turning on a preview mode of the digital camera to display a mother image of a digital image And at least one sub-picture; then, enter the menu of the preview item of the digital camera to select an item of interest, the item of interest is an exposure value item, a white balance item or a contrast item; next, capture an optical And converting the image into a digital image; then, calculating the digital image of the interest item and the at least one different interest item to generate a digital image of at least one different interest item: finally, displaying the digital image in the mother image, And displaying the digital image of the different interested items in the sub-picture.

When the selected item of interest is an exposure value item, the next step is to adjust the difference between the digital image and the sub-picture in the mother picture according to an exposure value step. A digital image of the value.

In addition, when the item of interest is a white balance item, the digital image in the mother picture is adjusted according to the digital image of the different white balance in the sub-picture.

Finally, when the selected item of interest is a contrast item, next, the digital image in the mother picture is adjusted according to the digital image of the contrast in the sub-picture.

In summary, the present invention can directly compare the image effects of the different exposure values (EV) on the LCD screen of the digital camera, so that the user can more conveniently select the appropriate exposure value image. In addition to the screen that can display the effect of the different exposure value (EV), the sub screen can also display a screen with a different white balance effect or a contrast effect (Contrast) effect. In order to solve the current digital camera, the brightness of the image in the LCD can only be observed by adjusting the exposure value (EV), and the effect of the contrast value (EV) cannot be directly observed on the same screen.

The above summary and the following detailed description are exemplary in order to further illustrate the scope of the claims. Other objects and advantages of the present invention will be described in the following description and drawings.

Please refer to FIG. 2A , which is a block diagram of a digital camera circuit with a preview function according to a first embodiment of the present invention. The digital camera 2 includes a lens 20 , a charge coupling unit 22 , a liquid crystal display panel 26 , and an exposure value calculation process. The unit 23, a white balance/contrast calculation processing unit 25, a sub-image processing unit 24, a memory unit 27 and a control button 28. The lens 20 is used to capture an optical image S1 after being focused. The charge coupled unit 22 is coupled to the lens 20 for converting the optical image S1 into a digital image S2.

Referring to the second A picture, the exposure value calculation processing unit 23 is coupled to the charge coupling unit 22 for calculating the exposure value of the digital image S2 and generating a difference from the exposure value. The digital image S3 of at least one distinct exposure value. The white balance/contrast calculation processing unit 25 is coupled to the charge coupling unit 22 for calculating the white balance/contrast of the digital image S2 and generating a digital image of at least one different white balance/contrast different from the white balance/contrast. S4. The sub-image processing unit 24 is coupled to the charge coupling unit 22, the exposure value calculation processing unit 23, the white balance/contrast calculation processing unit 25, and the liquid crystal display panel 26.

The image processing unit 24 displays the digital image S2 on the mother screen of the liquid crystal display panel 26, and displays the digital image S3 of the different exposure value or the digital image S4 of the different white balance/contrast on the sub-screen of the liquid crystal display panel 26. Medium for at least one user to preview. The aforementioned differential white balance/contrast digital image S4 includes a digital image with a different white balance and a digital image with a different contrast.

Referring to FIG. 2A, the memory unit 27 is coupled to the sub-image processing unit 24 for storing the digital image S2, the digital image S3 of the different exposure value, and the digital image S4 of the different white balance/contrast. The control button 28 is coupled to the sub-image processing unit 24 for controlling the sub-image processing unit 24 to perform selection of various menu items.

With reference to the second A picture, referring to the third figure, it is a schematic diagram of the mother-child picture of the digital camera with the exposure value preview function of the present invention. Referring to the third figure, the digital camera 2 displays a mother screen 262, a first sub-picture 264, and a second sub-picture 266 on the liquid crystal display panel 26 by executing the preview mode. At this time, the preview mode provides the digital display panel 26 to display the digital image S3 of the different exposure values in the first sub-picture 264 and the second sub-picture 266, and the digital display image S2 in the mother picture 262. The mother screen 262 displays a digital image S2 having an exposure value of 0 EV, and the first sub-picture 264 displays a digital image S3 having an exposure value of -1 EV, and the second sub-picture 266 displays a digital image S3 having an exposure value of +1 EV.

In this way, the user can use the first sub-picture 264 and the second sub-picture 266 to preview the digital image S3 of the exposure value -1 EV and the digital image of the exposure value + 1 EV. The effect of S3. Moreover, the user can control the sub-image processing unit 24 by operating the control button 28 to adjust the exposure value of the digital image S2 displayed on the mother screen 262. At this time, the first sub-picture 264 and the second sub-picture 266 are based on An exposure value step to change the exposure value of the displayed digital image S2.

Referring to the third figure, when the exposure value of the digital image S2 displayed on the adjustment mother screen 262 is increased from 0 EV to +1 EV, the first sub-picture 264 displays the digital image S3 with an exposure value of 0 EV according to the exposure value step. And the second sub-picture 266 displays the digital image S3 with an exposure value of +2 EV according to the exposure value step. In addition, when the exposure value of the digital image S2 displayed on the adjustment mother screen 262 is reduced from OEV to -1 EV, the first sub-screen 264 displays the digital image S3 with an exposure value of -2 EV according to the exposure value step. The two sub-pictures 266 display a digital image S3 having an exposure value of 0 EV according to the exposure value step.

With reference to the second A picture, referring to the fourth figure, it is a schematic diagram of the mother-child picture of the digital camera with the white balance preview function of the present invention. Referring to the fourth figure, the digital camera 2 displays a mother screen 262 and a plurality of sub-pictures 268 on the liquid crystal display panel 26 by executing the preview mode. At this time, the preview mode provides the liquid crystal display panel 26 to display the digital image S4 of the different white balance in the plurality of sub-pictures 268, and to display the digital image S2 in the mother picture 262. The mother screen 262 displays a digital image S2 with a preset white balance, and the plurality of sub-pictures 268 display a white balance correction including a tungsten lamp, a fluorescent lamp, a fluorescent lamp, an outdoor, a daylight, a cloudy sky, and an automatic light source. Digital image S4 of different white balance.

In this way, the user can use the plurality of sub-pictures 268 to preview the effects of the digital image S4 of various white balance corrected white balances. Moreover, the user can control the sub-image processing unit 24 by operating the control button 28 to set the digital image S2 in the parent screen 262 according to the digital image S4 of the different white balance in the plurality of sub-pictures 268.

With reference to the second A picture, referring to the fifth figure, it is a schematic diagram of the mother-child picture of the digital camera with the contrast preview function of the present invention. Referring to the fifth diagram, the digital camera 2 displays a mother screen 262 and a plurality of sub-pictures 267 on the liquid crystal display panel 26 by executing the preview mode. At this time, the preview mode provides the liquid crystal display panel 26 to display the digital image S4 of the different contrast in the plurality of sub-pictures 267, and the digital image S2 to be displayed in the mother picture 262. The mother screen 262 displays a digital image S2 having a preset contrast, and the plurality of sub-pictures 267 display a digital image S4 including a contrast ratio of high, low, and normal contrast.

In this way, the user can use the plurality of sub-pictures 267 to preview the effect of the digital contrast image S4 of different contrasts of various contrasts. Moreover, the user can control the sub-image processing unit 24 by operating the control button 28 to set the digital image S2 in the parent screen 262 according to the digital image S4 of the contrast in the plurality of sub-pictures 267.

Referring to FIG. 2A, please refer to FIG. 2B, which is a block diagram of a digital camera circuit with a preview function according to a second embodiment of the present invention. The elements of the digital camera 2' of the second embodiment of the present invention are the same as those of the digital camera 2 of the first embodiment, and are denoted by the same symbols. The digital camera 2' of the second embodiment has the same circuit operation principle as the digital camera 2 of the first embodiment, and the main difference is that the digital camera 2' of the second embodiment will be the first embodiment. The control button 28 of the digital camera 2 is removed, and the liquid crystal display panel 26 is changed to a touch panel 26'. The touch panel 26' is used to control the selection of various menu items by the sub-image processing unit 24.

With reference to the second A figure, referring to the sixth figure, the flow chart of the method of the present invention is shown. The method of the present invention is applicable to the preview mode of the aforementioned digital camera 2, and the step includes, when the digital camera 2 turns on the preview mode, a plurality of sub-pictures and a mother picture are displayed on the liquid crystal display panel 26 (S10). Then, the user can enter the digital camera 2 In the menu of the preview item (S12), and using the operation of the control button 28 to select an item of interest (S14), the item of interest includes an exposure value item, a white balance item, and a contrast item. Next, an optical image S1 is captured, and the optical image S1 is converted into a digital image S2 (S15). Then, the interest item of the digital image S2 and the at least one different interest item are calculated to generate digital images of at least one different interest item, including digital image S3 with different exposure values or different white balance/contrast Digital image S4 (S16). Finally, according to the selection of the item of interest, the digital image S2 is displayed in the mother picture, and the digital image S3 showing the different exposure value or the digital image S4 of the different white balance/contrast is in the sub-picture (S17).

In the foregoing step (S16), when the item of interest is an exposure value item, the exposure value and the different exposure value item of the digital image S2 are calculated to generate the digital image S3 of the different exposure value, and further according to an exposure value step. The digital image S3 for adjusting the digital image S2 in the mother picture and the different exposure value in the sub-picture. At the same time, after the step (S17), the user can use the operation of the control button 28 to adjust the digital image S2 displayed on the mother screen 262. At this time, the plurality of sub-pictures will change the displayed different exposure according to the exposure value level. The digital image S3 of the value is provided to provide a digital image S3 for the user to preview the different exposure values. Finally, the user performs shooting in accordance with the digital image S2 in the mother screen (S18).

In addition, in the foregoing step (S16), when the item of interest is a white balance item, the white balance and the contrast white balance item of the digital image S2 are calculated to generate the digital image S4 of the different white balance. The mother screen will display the digital image S2, and the plurality of sub-pictures will display the digital image S4 including the tungsten white light, the fluorescent light, the fluorescent light, the outdoor, the daylight, the cloudy sky and the automatic light source, etc. Preview. In this way, the user can adjust the digital image S2 in the mother screen according to the digital image S4 of the different white balance in the sub-screen. Meanwhile, after the step (S17), the user can use the operation of the control button 28 to select the digital image S4 of the different white balance in the plurality of sub-pictures. One of them becomes the digital image S2 displayed on the mother screen. Finally, the user performs shooting in accordance with the digital image S2 in the mother screen (S18).

Furthermore, in the above step (S14), when the item of interest is a contrast item, the contrast and the contrast ratio item of the digital image S2 are calculated to generate a digital image S4 of different contrast. The mother screen will display the digital image S2, and the plurality of sub-pictures will display the digital image S4 including high, low, normal and other contrasts to provide the user with a preview. In this way, the user can adjust the digital image S2 in the mother screen according to the digital image S4 with different contrast in the sub-screen. At the same time, after the step (S17), the user can use the operation of the control button 28 to select one of the digital images S4 of the contrast in the plurality of sub-pictures to become the digital image S2 displayed on the mother screen. Finally, the user performs shooting in accordance with the digital image S2 in the mother screen (S18).

In summary, the present invention can directly compare the image effects of the different exposure values (EV) on the LCD screen of the digital camera, so that the user can more conveniently select the appropriate exposure value image. In addition to the screen that can display the effect of the different exposure value (EV), the sub screen can also display a screen with a different white balance effect or a contrast effect (Contrast) effect. In order to solve the current digital camera, the brightness of the image in the LCD can only be observed by adjusting the exposure value (EV), and the effect of the contrast value (EV) cannot be directly observed on the same screen.

The above description is only the preferred embodiment of the present invention, but the features of the present invention are not limited thereto, and any one skilled in the art can easily change or modify it in the field of the present invention. Both can be covered in the following patent scope of this case.

Convention:

Object image ‧‧‧105

Photography device ‧‧110

Voltage signal ‧‧‧115

Color filter array ‧‧‧120

Three primary color signals ‧‧‧125

White balance circuit ‧‧‧130

Image signals ‧‧‧135, 145, 155, 165, 175, 185

Color correction circuit ‧‧‧140

TFT-LCD‧‧‧190

Gamma Correction Circuit ‧‧‧150

Hue phase conversion circuit ‧‧‧160

Edge-enhanced circuit ‧‧170

Plane image adjustment circuit ‧‧‧180

this invention:

Digital camera ‧‧2, 2'

Lens ‧ ‧ 20

Charge coupled unit ‧‧22

Exposure value calculation processing unit ‧‧23

Mother image processing unit ‧‧24

White balance / contrast calculation unit ‧‧‧25

LCD panel ‧‧26

Memory unit ‧‧27

Control button ‧‧28

Optical image ‧‧‧S1

Digital image ‧‧‧S2

Digital image of different exposure values ‧‧‧S3

Digital image of different white balance/contrast ‧‧S4

Touch panel ‧‧26'

Mother screen ‧ ‧ 262

Subscreen ‧‧‧264, 266, 267, 268

The first figure is a block diagram of a pre-view system circuit of a TFT-LCD used by a conventional digital camera; and the second A is a block diagram of a digital camera circuit having a preview function according to the first embodiment of the present invention; FIG. 2B is a block diagram of a digital camera circuit having a preview function according to a second embodiment of the present invention; FIG. 3 is a schematic diagram of a picture of a child camera of a digital camera having an exposure value preview function according to the present invention; The figure of the present invention is a schematic diagram of a picture of a child of a digital camera having a white balance preview function; the fifth figure is a schematic diagram of a picture of a child of a digital camera having a contrast preview function; and a sixth figure is a schematic flow chart of the method of the present invention.

Digital camera ‧‧2

Lens ‧ ‧ 20

Charge coupled unit ‧‧22

Exposure value calculation processing unit ‧‧23

Mother image processing unit ‧‧24

White balance / contrast calculation unit ‧‧‧25

LCD panel ‧‧26

Memory unit ‧‧27

Control button ‧‧28

Optical image ‧‧‧S1

Digital image ‧‧‧S2

Digital image of different exposure values ‧‧‧S3

Digital image of different white balance/contrast ‧‧S4

Claims (11)

A digital camera having a pre-view function, comprising: a lens for capturing an optical image; a charge coupled unit coupled to the lens for converting the optical image into a digital image; an exposure value calculation processing unit And the charge coupling unit is configured to calculate an exposure value of the digital image and generate a digital image of the at least one different exposure value different from the exposure value; and a liquid crystal display panel, which can display a mother image And at least one sub-picture; and a sub-male image processing unit coupled to the charge-coupled unit, the exposure value calculation processing unit, and the liquid crystal display panel, the sub-image processing unit displays the digital image on the mother image, And displaying the digital image of the different exposure value in the sub-picture for at least one user to preview. The digital camera having the pre-view function as described in claim 1 further includes a memory unit coupled to the image processing unit for storing the digital image and the different exposure value. Digital image. The digital camera with the pre-view function as described in claim 2, further comprising at least one control button coupled to the sub-image processing unit for controlling the sub-image processing unit to execute various menus Selection of the project. The digital camera with the pre-view function as described in claim 1 further includes a white balance/contrast calculation processing unit coupled to the charge coupled unit for calculating white balance/contrast of the digital image, and Produces a digital image of at least one phase white balance/contrast that is different from the white balance/contrast. a digital camera having a preview function as described in claim 4, wherein the image processing unit displays the digital image on the mother image, and The digital image of the contrast white balance/contrast is displayed in the sub-picture for at least one user to preview. The digital camera with the pre-view function as described in claim 1, wherein the liquid crystal display panel is a touch panel, and the image processing unit is controlled to perform selection of various menu items. A method for previewing an image of interest by using a picture of a mother and child, suitable for a preview mode of a digital camera, comprising: a. turning on a mother-picture pre-view mode to display a mother picture and at least one sub-picture; b. entering Preview the menu of the item to select an item of interest, the item of interest is an exposure value item, a white balance item or a contrast item; c. capture an optical image and convert it into a digital image: d. The interest item of the digital image and the at least one different interest item to generate a digital image of at least one different interest item: and e. displaying the digital image in the mother picture, and displaying the different interest The digital image of the item is in this sub-picture. For example, in the method of claim 7, the method for previewing an image of interest by using a picture of a child, the step d further includes: when the item of interest is the item of exposure value, adjusting according to an exposure value step. The digital image in the mother screen and the digital image of the different exposure value in the sub-picture. In the method of claim 7, the method for previewing the image of interest by using the mother-in-picture, the step d further includes: when the item of interest is the white balance item, according to the different white balance in the sub-picture The digital image to adjust the digital image in the mother picture. The method for previewing an image of interest by using a mother-in-picture as described in claim 7 of the patent application, further comprising, in step d, when the item of interest is the contrast item For example, the digital image in the mother screen is adjusted according to the digital image of the contrast in the sub-picture. For example, the method for previewing an image of interest by using a mother-in-picture as described in claim 8, 9 or 10, after step e, further comprises: performing shooting according to the digital image adjusted in the mother screen.