Method and apparatus for retouching photographed image

A method and an apparatus for retouching a photographed image is provided. The method includes steps for recognizing an image region which is to be retouched in the photographed image and for retouching the recognized image region. Thus, the photographed image can be retouched easily using the digital camera by which the image was photographed without the use of a computer in an environment where portable printers for digital camera are supplied.

This application claims priority to Korean Patent Application No. 2002-63530, filed on Oct. 17, 2002, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.

FIELD OF THE INVENTION

The present invention relates to a process for retouching an image photographed by a digital camera, and particularly, to a method and an apparatus for retouching a photographed image directly on the digital camera itself.

BACKGROUND OF THE INVENTION

Recently, digital cameras have been widely used instead of optical cameras. A digital camera is a camera functioning as a camera and a scanner by storing any visible object or landscape in a digital storing medium. An optical camera stores an image as an analog quantity; however, a digital camera divides the image into bit maps and records the respective brightness as a digital quantity. Since a digital camera is highly compatible with image data stored in a personal computer, a photographed image can be edited and retouched easily, stored in an inner memory (for example, a hard disk or a memory card), and transmitted to a networked computer.

An image photographed by a digital camera can be retouched by one of the following modes: a sepia mode, a tungsten mode, and a sharpening mode. The sepia mode is an image processing mode for processing the entire image into a mono-color such as brown, the tungsten mode is an image processing mode for processing the entire image by emphasizing the color red in the color balance, and the sharpening mode is a processing mode for clarifying the image by shielding low frequencies and maintaining high frequencies using a low frequency shielding filter.

However, in a conventional digital camera, noise (here, noise means irregular pixel values in the image) or an undesirable object in the image (for example, blemishes on a person's face) may be retouched using an image tool, such as Photoshop®, after transmitting image data to the computer.

SUMMARY OF THE INVENTION

The present invention provides a method of retouching a photographed image wherein an image photographed by a digital camera can be retouched directly on the digital camera itself.

Another embodiment of the present invention is directed to a method of retouching a photographed image which includes recognizing an image region to be retouched in the photographed image, and retouching the recognized image region.

The present invention is also directed to a method for retouching a photographed image using a digital camera which includes step (a) and step (b) wherein step (a) includes recognizing an image region which is to be retouched in the photographed image, and step(b) includes retouching the recognized image region, wherein steps (a) and (b) are performed on the digital camera.

The present invention also provides an apparatus for retouching a photographed image wherein an image photographed by a digital camera can be retouched directly on the digital camera itself.

A further embodiment of the present invention is directed to an apparatus for retouching a photographed image using the digital camera on which the image was taken which includes a region recognition unit for recognizing an image region which is to be retouched in the photographed image and outputting the recognized image region and a region retouch unit for retouching the recognized image region input from the region recognition unit and outputting the retouched result.

Another embodiment of the present invention is directed to an apparatus for retouching a photographed image using a digital camera which includes a region recognition unit for recognizing an image region which is to be retouched in the photographed image and outputting the recognized image region and a region retouch unit for retouching the recognized image region input from the region recognition unit and outputting the retouched result, wherein the region recognition unit and the region retouch unit are located on the digital camera.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1is a flow chart of a photographed image retouching method according to an embodiment of the present invention and includes steps for recognizing and correcting an image region which needs to be retouched (steps10and12).

First, an image region which needs to be retouched is recognized by the digital camera (step10). If a user sets a recognition range for an image region containing noise or impurities, the corresponding image region is recognized by the digital camera.

Then, the recognized image region is retouched (step12). When the region containing the noise or objects to be omitted in the photographed image is recognized by the digital camera in step10, the recognized region is retouched.

Step12may also include a method of blurring. Blurring is a method of processing an image by removing high frequency components in order to soften the image. Low frequency is the frequency associated with a small changing rate of pixel values, and high frequency is the frequency associated with a large changing rate of pixel values. When the high frequency components are removed from the image, the changing rate of the pixel values is reduced, and accordingly, extreme values for neighboring pixels are also reduced to soften the image. Therefore, fine noise or impurities in the image can be weakened through the blurring process.

FIG. 2is a flow chart of another embodiment (step12A) of the present invention shown inFIG. 1. Step12A includes steps20-32for copying an image region having similar color information to that of the image region which needs to be retouched, substituting the color information, and blurring the image.

After performing step10, a first filter window having the same size as the recognized image region is formed (step20). The size of the first filter window can be controlled according to the size of recognized image region.

Additionally, the first filter window is disposed on the image region having color information similar to that of the recognized image region (step22). For example, in order to remove impurities in the image, the first filter window is disposed on the image region having the similar color information to that the impurities.

The image region on which the first filter window is disposed is copied (step24). For example, the image region having the same size as the first filter window disposed on a position having the similar color information to that of an area adjacent to the impurities is copied.

Then, the first filter window having color information of the copied image region is disposed on the recognized image region (step26). For example, the image region copied as much as the first filter window is covered on the image region which is adjacent the impurities.

In addition, the color information of the recognized image region is substituted with the color information of the copied image region included in the first filter window (step28). That is, the color information on the image region having the impurities is substituted with the color information of the copied image region to obtain an image region with no impurities.

After performing step28, a peripheral image region including the substituted image region is recognized by the digital camera (step30). For example, the impurities of the substituted image region are removed by the first filter window; however, edges of the image region may not be balanced with the remaining portion of the image around image regions. In order to balance the edge portions, the region containing the edge portions of the substituted image region is recognized by the digital camera to be blurred. The image region containing the edge portions of the first filter window is called a peripheral image region, and the peripheral image region is recognized by region setting by the user.

The recognized peripheral image region is blurred (step32). The slight unbalance shown at the edge portions of the substituted image can be removed through blurring.

FIG. 3is a flow chart containing a step for expanding the recognized image region in the photographed image retouching method shown inFIG. 1, and includes steps for correcting the expanded image region (steps40-44).

An image region to be retouched in the photographed image is recognized by the digital camera (step40).

Thereafter, the recognized image region is expanded (step42) by moving coordinates of respective pixels in the recognized image as expanding magnifications. When there are pixels that are not assigned data values for use in expanding the image, then an interpolation method can be employed for assigning appropriate data values to empty pixels.

Next, the expanded image region is retouched (step44).

FIG. 4is a flow chart for describing another embodiment (44A) of step44as shown inFIG. 3that includes steps for recognizing and blurring a fine retouch region in the expanded image region (steps50and52).

After performing step42, the detailed retouch region in the expanded image region is recognized by the digital camera (step50). The fine retouch region is an image region that the user wishes to correct in the expanded image region. The region set by the user is recognized as the detailed retouch region.

Thereafter, the recognized detailed retouch region is blurred (step52).

FIG. 5is a flow chart for describing a further embodiment (44B) of step44as shown inFIG. 3that includes steps for copying an image region having color information similar to that of the detailed retouch region, substituting color information, and blurring the image (steps60˜72).

After performing step42, a second filter window of the same size as the detailed retouch region in the expanded image region is formed (step60). The size of the second filter window can be controlled according to the size of the detailed retouch region.

The second filter window, which is disposed on an image region having color information similar to that of the detailed retouch region, is disposed (step62). For example, the second filter window is disposed on the image region having color information similar to that of an area adjacent to the impurities in order to correct the detailed retouch region in which the impurities exist.

In addition, the image region on which the second filter window is disposed is copied (step64). For example, the image region is copied as large as the second filter window which is disposed on a portion having color information similar to that of the area adjacent to the impurities.

The second filter window, having color information of the copied image region, is disposed on the detailed retouch region (step66). That is, the image region copied as large as the second filter window is disposed on the detailed retouch region in which the impurities exist.

After performing step66, the color information on the detailed retouch region on which the second filter window is disposed is substituted with color information of the copied image region (step68). For example, the color information of the detailed retouch region in which the impurities exist is substituted with the color information of the copied image region. Accordingly, the image region without the impurities can be obtained from the image region having the impurities through color information substitution.

Additionally, the peripheral image region including the substituted detailed retouch region is recognized by a digital camera (step70). For example, the impurities of the detailed retouch region are removed by the second filter window; however, edge portions of the substituted detailed retouch region may not be balanced with other image regions. In order to balance the edge portions, the peripheral image region including the edge portions of the substituted detailed retouch region is recognized.

The recognized peripheral image region is blurred (step72). The fine image differences shown at the edge portions of the substituted detailed retouch region can be removed through blurring.

Constructions and operations of the photographed image retouching apparatus according to the present invention will be described as follows with reference to accompanying drawings.

FIG. 6is a block diagram of the photographed image retouching apparatus according to an embodiment of the present invention. The apparatus includes a region recognition unit100and a region retouch unit120.

The region recognition unit100recognizes the image region, which is to be retouched in a photographed image region, and outputs the recognized image region (step10). For example, when the user sets a range for an image region in which noise or impurities are seen in the photographed image input through an input terminal IN1, the region recognition unit100recognizes the set image region and outputs the recognized result to the region retouch unit120.

The region retouch unit120retouches the recognized image region input from the region recognition unit100, and outputs the retouched result through an output terminal OUT1(step12). An example of the region retouch unit120may include a blurring unit (not shown) for blurring the recognized image region input from the region recognition unit100and outputting the blurred image region.

FIG. 7is a block diagram of another embodiment (120A) of the region retouch unit120as shown inFIG. 6. The region retouch unit120A includes a filter window forming unit200, a filter window moving unit210, a region copying unit220, a color information substituting unit230, a peripheral region recognizing unit240, and a peripheral region blurring unit250.

The filter window forming unit200forms the first filter window having the same size as the recognized image region and outputs the formed first filter window. The size of the window formed by the filter window forming unit200varies, depending on the size of the area of the recognized image region. The window may include several windows having selective sizes, or may be a window that can be adjusted. For example, the filter window forming unit200receives the recognized image region from the region recognition unit100through an input terminal IN2, forms the first filter window having the same size as the recognized image region, and outputs the first filter window to the filter window moving unit210(step20).

The filter window moving unit210moves the first filter window received from the filter window forming unit200on a screen of the digital camera, and outputs the moved result (steps22and26). For example, the filter window moving unit210moves the first filter window to the image region having image information similar to that of the recognized image region, and outputs the moved result to the region copying unit220. Also, the filter window moving unit210moves the first filter window including the copied image region to the recognized image region, and outputs the moved result to the color information substituting unit230.

The region copying unit220copies the image region on which the first filter window is disposed, and outputs the copied image region in response to receive the moved result of the first filter window. For example, the region copying unit220receives the moved result of the first filter window input from the filter window moving unit210, copies the color information corresponding to the image region on which the first filter window is disposed, and outputs the copied result to the filter window moving unit210(step24).

The color information substituting unit230substitutes the color information of the recognized image region with the color information of the copied image region in response to receiving the moved result of the first filter window including the copied image region from the filter window moving unit210, and outputs the substituted result (step28). For example, the color information substituting unit230receives the moved result of the first filter window on the copied image region from the filter window moving unit210, substitutes the color information on the recognized image region with the color information of the image region copied by the region copying unit220, and outputs the substituted result to the peripheral region recognizing unit240.

The peripheral region recognizing unit240recognizes the peripheral image region including the substituted image region in response to receiving the substituted image region from the color information substituting unit230, and outputs the recognized peripheral image region (step30). For example, the peripheral region recognizing unit240recognizes the image region including edge portions of the first filter window. The size of the peripheral image region can be controlled by the user.

The peripheral region blurring unit250blurs the recognized peripheral image region input from the peripheral region recognizing unit240, and outputs the blurred peripheral image region (step32). For example, the peripheral region blurring unit250blurs the recognized peripheral image region input from the peripheral region recognizing unit240, and outputs the blurred peripheral image region through an output terminal OUT2. Therefore, the noise shown in the image can be removed through blurring.

FIG. 8is a block diagram of the photographed image retouching apparatus further including a region expanding unit120according to another embodiment of the present invention.

A region recognition unit300recognizes an image region which is to be retouched in the photographed image, and outputs the recognized image region (step30). For example, when the user sets a rough range for the image region in which noise or impurities exist in the photographed image, the region recognition unit300recognizes the set image region, and outputs the recognized result to the region expanding unit320.

The region expanding unit320expands the recognized image region input from the region recognition unit300and outputs the expanded image region (step42). For example, the region expanding unit320uses a nearest neighbor interpolation method or a zero-order interpolation method to expand the size of an image. The nearest neighbor interpolation method is a method of assigning a neighboring pixel value to an empty pixel so as to expand the image, and the zero-order interpolation method is a method of substituting an average value of surrounding pixels to an empty pixel in the expanded image. The region expanding unit320expands the recognized image region input from the region recognition unit300and outputs the expanded image region to a region retouching unit340.

The region retouching unit340retouches the expanded image region input from the region expanding unit320and outputs the retouched result (step44). The region retouching unit340retouches the recognized image region and outputs the retouched result through an output terminal OUT3.

FIG. 9is a block diagram of another embodiment340A of the region retouching unit340shown inFIG. 8, and the region retouching unit340A includes a detailed retouch region recognizing unit400and a detailed retouch region blurring unit420.

The detailed retouch region recognizing unit400recognizes the detailed retouch region in the expanded image region and outputs the recognized detailed retouch region. For example, the detailed retouch region recognizing unit400receives the expanded image region from the region expanding unit320through an input terminal IN4, recognizes the detailed retouch region set by the user in the expanded image region, and outputs the recognized detailed region.

The detailed retouch region blurring unit420blurs the detailed retouch region input from the detailed retouch region recognizing unit400and outputs the blurred detailed retouch region. For example, the detailed retouch region blurring unit420blurs the detailed retouch region input from the detailed retouch region recognizing unit400and outputs the blurred detailed retouch region through an output terminal OUT4.

FIG. 10is a block diagram of still another embodiment (340B) of the region retouching unit340shown inFIG. 8, and the region retouching unit340B includes a filter window forming unit500, a filter window moving unit510, a region copying unit520, a color information substituting unit530, a peripheral region recognizing unit540, and a peripheral region blurring unit550.

The filter window forming unit500forms a second filter window having the same size as the detailed retouch region in the expanded image region and outputs the formed second filter window (step60). The window formed by the filter window forming unit500may be several windows, or may be a window of which the size can be adjusted. For example, the filter window forming unit500receives the expanded image region from the region expanding unit320through an input terminal IN5, forms the second filter window the same size as the detailed retouch region in the expanded image region, and outputs the second filter window to the filter window moving unit510.

The filter window moving unit510moves the second filter window input from the filter window forming unit500onto the screen of a digital camera, and outputs the moved result (steps62and66). For example, the filter window moving unit510moves the second filter window to an image region having color information similar to that of the detailed retouch region and outputs the moved result to the region copying unit520. Also, the filter window moving unit510moves the second filter window having a copied image region to the detailed retouch region and outputs the moved result to the color information substituting unit530.

The region copying unit520copies the image region on which the second filter window is disposed in response to receiving of the moved result of the second filter window, and outputs the copied image region (step64). For example, the region copying unit520receives the moved result of the second filter window input from the filter window moving unit510, copies the color information corresponding to the image region on which the second filter Window is disposed, and outputs the copy result to the filter window moving unit510.

The color information substituting unit530substitutes the color information of the detailed retouch region with the color information of the copied image region in response to receiving the moved result of the second filter window including the copied image region from the filter window moving unit510, and outputs the substituted result (step68). For example, the color information substituting unit530receives the moved result of the second filter window on the copied image region from the filter window moving unit510, substitutes the color information of the detailed retouch region with the color information of the image region copied by the region copying unit520, and outputs the substituted result to the peripheral region recognizing unit540.

The peripheral region recognizing unit540recognizes the peripheral image region, including the substituted image region, in response to receiving the substituted image region from the color information substituting unit530, and outputs the recognized peripheral image region (step70). For example, the peripheral region recognizing unit540recognizes the image region including edge portions of the second filter window. The size of peripheral image region can be controlled by the user.

The peripheral region blurring unit550blurs the recognized peripheral image region input from the peripheral region recognizing unit540and outputs the blurred peripheral image region (step72). That is, the peripheral region blurring unit550blurs the peripheral image region input from the peripheral region recognizing unit540and outputs the blurred peripheral image region through an output terminal OUT5. Therefore, fine noise shown in an image can be removed through blurring.

FIG. 11is a view of the functional keys located on the rear surface of a digital camera directed to the present invention, the keys include an image display unit600, a filter window moving key610, a blurring key620, and an impurity removal key630. The image display unit600displays the photographed image, the filter window moving key610moves the filter window by the filter window moving unit210or510, the blurring key620performs the functions of the blurring unit (not shown) or the detailed retouch region blurring unit420, the impurity removing key630performs the functions of the filter window forming unit200or500, the filter window moving unit210or510, the region copying unit220or520, and the color information substituting unit230or530. The image display unit600ofFIG. 11displays a filter window604selectively formed by the filter window forming unit500ofFIG. 10, and a blurring or impurity removal mode602enacted by the blurring key620or the impurity removal key630.

FIG. 12is an exemplary view of the process of removing impurities using the photographed image retouch apparatus shown inFIGS. 8 through 10.

FIG. 12(a) is a view of a photographed image containing impurities which a user has set on the image display unit600.

FIG. 12(b) is a view of a certain region recognized by the region recognition unit300shown inFIG. 8when the user selects the impurity removing key630ofFIG. 11, thereby relaying detailed information of the region on which the impurities exist.

FIG. 12(c) is a view of a particular region expanded by the region expanding unit320which allows the user to clearly identify the region on which the impurities exist in the expanded image.

FIG. 12(d) is a view of the second filter window disposed on an image region {circle around (b)} having color information similar to that of the region {circle around (a )} on which the impurities exist using the filter window moving key610ofFIG. 11. Here, the second filter window corresponding to the image region {circle around (b)} having similar color information is formed by the filter window forming unit500shown inFIG. 10.

FIG. 12(e) is a view of the image region {circle around (b)} having similar color information moved to the predetermined region {circle around (a)} on which impurities exist. The image region {circle around (b)} having similar color information is copied by the region copying unit520shown inFIG. 10, moved by the filter window moving unit510, and displayed as (e) ofFIG. 12.FIG. 12(f) is a view of the image region {circle around (a)} on which the impurities exist substituted with the image region {circle around (b)} having similar color information to that of the image region {circle around (a)}; thus, the image region {circle around (a)} is substituted by the color information substituting unit530ofFIG. 10and displayed with no impurities.

The blurring process may be performed additionally for the image region on which the impurities are removed to obtain a desired image.

As described above, according to the method and apparatus for retouching the photographed image of the present invention, a photographed image can be retouched directly on a digital camera without the need for a computer while portable printers for the digital camera are distributed widely.