JPH10233919A - Image processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To output an image that has a stereoscopic effect and a depth feeling with a simple operation by automatically making a main part sharp and giving background an out-of-focus effect (foreground out-of-focus effect) that shades off the background. SOLUTION: A photoprinter 10 consists of a scanner 12, an image processor (processor) 14 and a printer 16. The processor 14 has a detecting part 18 and an image processing part 20, performs image processing of image data that is read by the scanner 12, etc., in accordance with prescribed image processing and the instruction of an operator and makes it image data for image recording by the printer 16. When image information of two same images that have different focus conditions is received and when the main part and background of the image are detected, image processing that makes the main part and background different is performed to at least one of image information of the two images in accordance with the detection result. Not only normal image processing but also, what is called, a background out-of-focus (foreground out-of- focus) effect are given to an image to be formed, that is, the main part is accurately brought into a focus and the background is suitably shaded off.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of an image processing apparatus used for a digital image reading / reproducing apparatus and the like, and more specifically, outputs an image having a three-dimensional effect and a depth effect by a simple operation. The present invention relates to an image processing apparatus that enables the above.

[0002]

2. Description of the Related Art At present, an image photographed on a photographic film (hereinafter, referred to as a film) such as a negative film or a reversal film is printed on a photosensitive material such as photographic paper by projecting light of the film onto the photosensitive material. So-called direct (analog) exposure, which exposes a photosensitive material with this projection light, is the mainstream.

On the other hand, in recent years, a printing apparatus using digital exposure, that is, an image captured on a film is photoelectrically read, and the read image is converted into a digital signal, and then subjected to various image processing. 2. Description of the Related Art A digital photo printer that scans and exposes a photosensitive material with recording light modulated according to the image data, records an image (latent image), develops the image, and outputs it as a print (photograph) is used as image data for recording. It was put to practical use.

In a digital photo printer, a film is read photoelectrically, and color density correction is performed by signal processing to determine exposure conditions. Therefore, the operator does not need to determine the exposure conditions and adjust the filters and the like at the time of exposure.
Also, since the exposure time is constant according to the image size,
Efficient work can be performed. Further, according to the digital photo printer, it is possible to output a print reproducing a higher quality image in terms of resolution, color / density reproducibility, etc. as compared with the conventional direct exposure print. It is also possible to freely perform image processing such as image editing such as synthesis and division, color / density adjustment, and edge enhancement, and output a print that has been freely processed according to the application.
Furthermore, since a print image is basically handled as image data, not only print output but also image data can be supplied to a computer or the like, or stored as image data in a storage medium such as a floppy disk. You can keep it. Further, images (image data) captured by a digital camera (electronic still camera), a digital video camera, or the like, and images stored in the recording medium can be output as prints.

[0005] Such a digital photo printer basically comprises a scanner (image reading device), an image processing device, and an image recording device (printer). The scanner obtains projection light carrying the captured image by inputting the reading light to the film, forms the projection light on an image sensor such as a CCD sensor, and photoelectrically converts the projection light into an image. The image is read and sent to an image processing device as film image data (image data signal). The image processing apparatus receives the image data sent from the scanner, performs predetermined image processing, and sends the image data to a printer as image data (exposure conditions) for recording. The printer receives the image data output from the image processing device, and modulates the light beam according to the image data sent from the image processing device, for example, if the device uses light beam scanning exposure, and The photosensitive material (printing paper) is conveyed in a sub-scanning direction orthogonal to the main scanning direction, and is scanned and exposed (printed) by a light beam to form a latent image. Then, the image photographed on the film is output as a reproduced print.

[0006]

By the way, as a process for reproducing a high-quality image in which a three-dimensional effect and a depth effect are suitably reproduced, a main part (main subject) is accurately focused on, and a background is focused. A so-called rear blur (or front blur) effect in which the image is suitably blurred is known. In a conventional direct exposure photo printer, it is essential to use an expensive single-lens reflex camera or the like for photographing in order to obtain an image with a bokeh effect. Inexpensive cameras such as film with a lens such as (1) tend to be able to perform only pan-focus shooting in which the entire screen is in focus. Therefore, it is impossible to obtain an image with a rear blur effect. On the other hand, with the above-described digital photo printer, it is possible to form an image with a rear blur effect from an image captured by a compact camera or the like by image processing.

[0007] The image to which the back bokeh effect is given by image processing is cut out of the main part from the image using an image processing tool such as a commercially available photo retouching software such as Photoshop (made by Adobe), and the main part is sharpened. (Sharpness)
It can be formed by subjecting the background portion to a blurring process and then combining the main portion and the background portion. That is, in order to add a rear blur effect to an image by image processing, a clipping process is necessary. However, since the clipping process is complicated and almost impossible to perform automatically, an operator uses a user interface or the like. It is necessary to carry out cutting work. In addition, as described above, since the clipping operation is complicated, depending on the image, the operation is extremely time-consuming and time-consuming, and often places a heavy burden on the operator.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and to use an image processing tool or the like even from an image taken by an inexpensive camera such as a compact camera or a film with a lens or a digital camera. Image processing that automatically forms an image with a sharp back-blur effect (front blur effect) in which the main part is sharp without performing complicated work such as clipping work by the operator It is to provide a device.

[0009]

To achieve the above object, the present invention provides a detecting means for receiving image information of two same images having different focus conditions and detecting a main part of the image and a background. And an image processing unit that performs different image processing for at least one of the image information of the two images between a main part and a background in accordance with the detection result. .

In the image processing means, it is preferable that the image processing performed on the main part is a sharpening processing and the image processing performed on the background is a blur processing.

Further, the two images are one of which is an image focused on a main part, the other is an image focused on a background, and the detecting means uses an edge component of the two images. Preferably, the main part and the background of the image are detected.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an image processing apparatus according to the present invention will be described in detail based on a preferred embodiment shown in the accompanying drawings.

FIG. 1 is a block diagram showing an example of a digital photo printer using the image processing apparatus of the present invention. Digital photo printer 10 (hereinafter, photo printer 10)
Is to create a print that reproduces images taken on film such as strips in which many images are taken on long film, slides in which a reversal film is held on a frame, etc. is there. Such a photo printer 10 includes a scanner 12 as a reading device that photoelectrically reads an image photographed on a film, and a scanner 12.
An image processing device 14 of the present invention (hereinafter, referred to as a processing device 14) that performs predetermined image processing on image data or the like of a film read in step 1 and outputs the processed image data as image data for output
And a printer 16 that is a recording device that scans and exposes the photosensitive material with a light beam modulated in accordance with image data output from the processing device 14, performs a development process, and outputs the print as a print. .

A scanner 12 that photoelectrically reads an image captured on a film is provided with a light source, a variable aperture, and a color that separates the image captured on the film into three primary colors of R (red), G (green), and B (blue). Filter plate, imaging lens unit, CC
It is a known image reading device having an image sensor such as a D sensor, an A / D (analog / digital) converter, an LUT (lookup table) for log-converting a signal, and the like.

In the scanner 12, a reading light, which is emitted from a light source, adjusted in light amount by a variable aperture, passes through a color filter plate, and is color-adjusted, enters the film and transmits, thereby photographing the film. Obtain projection light carrying the image. The projection light of the film is imaged on the light receiving surface of the CCD sensor by the imaging lens unit, and is read photoelectrically. The output signal from the CCD sensor is A / D
The signal is converted into a digital signal by a converter, log-converted by an LUT, and sent to the processing device 14 as (digital) image data of an image captured on a film. The scanner 12 performs such image reading three times by sequentially inserting the R, G, and B color filters, and separates and reads the image captured on the film into the three primary colors of R, G, and B. .

The processing unit 14 has a detecting unit 18 and an image processing unit 20 and performs predetermined image processing on image data read by the scanner 12 or the like or image processing in accordance with an operator's instruction. , And is configured by combining a CPU, a memory, various image processing circuits, and the like. Further, the processing device 14
In addition to image processing, it controls and manages the entire photo printer 10. In addition to the image processing-related parts, the CPU that controls the operation of the entire photo printer 10 and various instructions and management, and the entire photo printer 10 A memory for storing data necessary for the operation, means for determining the aperture value of the variable aperture in the main scan, and the like are provided. In addition, various conditions and processing instructions (settings), frames to be printed, the number of prints, and colors are provided. A keyboard 36 and a mouse 38 for inputting instructions such as density correction and the like, images read by the scanner 12, various operation instructions, setting / registration screens for various conditions and specifications such as school photo patterns, and the like. A display 40 for displaying is connected. Therefore, such a processing device 14 is generally constituted by a workstation, a computer, or the like.

The image data processed by the processing device 14 according to the present invention is not limited to image data supplied from the scanner 12 for reading a film image shown in the figure, but may also be a digital camera (electronic still camera), a digital video camera, or the like. The data may be image data of an image photographed in the above or image data read by a reading device of a reflection original such as a printed matter, or may be stored in a storage medium such as a floppy disk or MO (magneto-optical storage medium). Image data.

When a print is to be created (output of processed image data) by normal image processing, image data supplied from the scanner 12 or the like is sent to the image processing unit 20. The image processing unit 20 performs color / density correction, compression / expansion of a dynamic range of an image holding an intermediate gradation (providing a dodging effect by image processing) on the supplied image data,
The image data is subjected to predetermined image processing such as image scaling processing, that is, electronic scaling processing, image sharpening (sharpness) processing, and the like.
Output to Note that, in the processing device 14, before the image processing (or the application of the later-described blurring effect described later), the image data supplied from the scanner 12 or the like may be subjected to DC offset correction as necessary. Various corrections such as darkness correction and shading correction may be performed.

Here, the processing device 14 according to the present invention comprises:
In addition to such normal image processing, an image to be formed can be given a so-called back blur (front blur) effect in which the main part is accurately focused and the background is appropriately blurred. Hereinafter, together with the operation when imparting the back blur effect, the configuration of the image processing apparatus of the present invention,
This will be described in more detail.

When the rear blur effect is applied, the processing unit 14 supplies the image data of two images having the same image but different focusing conditions, specifically, exactly the same image (scene), Two pieces of image data, that is, image data of an image focused on (main subject) and image data of an image focused on the background are supplied. In the processing device 14, both image data are sent to the detection unit 18, and only image data of the image focused on the main part is sent to the image processing unit 20. For example, such an image is obtained by fixing a camera (optical camera, digital camera, digital video camera, etc.) with a tripod or the like, first focusing on a main part, and then focusing on a background. A method of taking a picture, a method of using a camera having a line-of-sight sensor of a focal position, changing the focal position with a line of sight without moving the camera, and photographing two images, focusing on a certain point (usually a main part) If the camera does not move for a predetermined time after the shooting, the camera can be obtained by various means such as a method using a camera that automatically shoots with the focus position adjusted to the background.

The detecting section 18 which has received the image data of the two types of images extracts the edge components of both images, for example, a high frequency component or a further intermediate frequency component, and outputs the absolute value. Hereinafter, the absolute value of the (medium) high frequency component of the image focused on the main part is | Y ^(a) _MH |, and the absolute value of the (medium) high frequency component of the image focused on the background is | Y ^(b) _MH |. The (medium) high frequency component is
A known method such as a method using a high (band) pass filter or a method of generating a low frequency component with a low pass filter and then subtracting the low frequency component from the original signal may be used.

FIG. 2 schematically shows the image density (image data) of one and the same pixel line and the middle and high frequency components in two images in which the main part and the background are focused on the same image. Show. The example shown in FIG. 2 is an example of an image having a main part in the center, FIG. 2 (a-1) shows the density of the image focused on the main part, and FIG. The absolute value of the middle and high frequency components | Y ^(a) _MH |
Is the density of the image focused on the background, and FIG.
-2) is the absolute value | Y ^(b) _MH | of the middle and high frequency components.

Next, the detection unit 18 takes the difference between | Y ^(a) _MH | and | Y ^{(b )} _MH |, for example, as shown below. Y _sub = | Y ^(a) _MH | − | Y ^(b) _MH | FIG. 3A shows “Y _sub = | Y ^(a) _MH | − in FIG.
| Y ^(b) _MH |]. As is clear from the figure, by taking this difference, it is possible to determine whether the corresponding image data (pixel) is the main part or the background by the sign.
That is, the boundary between the main part of the image and the background (so-called edge part) can be made clear.

In the present invention, in addition to the method using the (middle) high frequency component, two main images having different focus conditions are used, and the main part, the background, and the edge part of the image are used. Various detection methods are available.

The result of the determination by the detecting section 18 is sent to the image processing section 20. The image processing section 20 adds the detection section 18 to the image data of the image focused on the main section sent earlier.
According to whether the image data (pixel) determined as _Ysub is the main part or the background, if the main part, sharpness (sharpening) processing is applied, if it is the background, the blur processing is applied, and the back blur processing effect (Image data) assigned with.
It should be noted that an image in which the background is in focus may be used as an image to which the rear blur processing effect has been applied, according to an intended image. As shown in FIG. 3, in this example,
If Y _sub > 0, sharpness processing is applied because it is the main part, and if Y _sub <0, blur processing is applied because it is the background. FIG. 3B shows the image (image data) of FIG. 2A after being subjected to the sharpness processing or the blur processing according to the determination.

Therefore, according to the image processing apparatus of the present invention,
Automatically forms an image to which the main part is sharp and the background is blurred, and the background is blurred, from the provided image data, eliminating the need for the operator to cut out the main part using the image processing tool. It is possible to create a print in which a high-quality image having a three-dimensional effect and a depth effect is recorded by a simple operation.

The above example is an example in which an image in which the main part is in focus and an image in which the background is in focus are used. Even if the image is not focused on, if the main part is defocused, it is possible to extract the boundary between the main part of the image and the background, although the accuracy is reduced. Further, in the image processing apparatus of the present invention, since a difference in optical image magnification occurs between the two images due to a difference in the focus condition, it is preferable to set the focus condition by a method such as obtaining information on the focus condition from a camera. It is preferable to know and perform geometrical matching of the two images. In this case,
For example, after the image focused on the background is subjected to geometric correction so as to adjust the image focused on the main part, the boundary between the main part of the image and the background may be extracted. Further, in the present invention, after obtaining Y _sub as described above, the connection processing of the area of Y _sub > 0 and the connection processing of the area of Y _sub <0 are respectively performed, so that two areas of the image are obtained. Then, a sharp result and a blur process are applied to each of the divided images to obtain a favorable result in that a blurring effect can be more appropriately provided.

The method of the sharpness processing is not particularly limited, and various known methods can be used. For example, USM
(Unsharpness mask)
Japanese Patent Laid-Open No. 26678/1995 extracts a luminance signal and a chrominance signal from image data, performs spatial filter processing on the luminance signal to calculate spatial information, and performs predetermined emphasis processing on the spatial information to newly generate spatial information. A method for obtaining a suitable luminance signal and combining the luminance signal and the color signal to obtain processed image data. The method described in Japanese Patent Application No. 7-337510 by the applicant of the present invention, After decomposing into a component, a medium frequency component and a high frequency component, extracting a luminance component from the medium frequency component and the high frequency component, suppressing the extracted medium frequency component and emphasizing the high frequency component, A method of synthesizing the obtained middle frequency component, high frequency component, and low frequency component to obtain processed image data is exemplified.

On the other hand, there is no particular limitation on the method of the blur processing, but a method of blurring using a low-pass filter, a method of averaging, a method of using an image processing tool such as retouching software, for example, a filter of Adobe Photoshop, Various known methods such as a method of giving a characteristic blur by blurring (moving) and blurring (radial) can be used.

In the processing device 12 of the present invention, the rear blur effect is imparted by such image processing even after the necessary image processing such as the above-described color / density correction and dynamic range compression / expansion is performed. Good, or may be subjected to the necessary image processing after applying the back blur effect, or, depending on the type of image processing, whether to perform processing before or after the application of the back blur effect You may choose.

As described above, the image data subjected to the predetermined image processing by the processing device 14 (image processing unit 20) is output to the printer 16 as image data for recording. The printer 16 exposes a photosensitive material with recording light modulated in accordance with image data, performs a predetermined development process, and outputs a print on which an image is formed (reproduced). In the case of an apparatus that uses a light source, the light beam is modulated in accordance with the image data sent from the processing device 14 to deflect the light beam in the main scanning direction, and a photosensitive material (printing paper) in the sub-scanning direction orthogonal to the main scanning direction. The photosensitive material is two-dimensionally scanned and exposed (printed) by a light beam to form a latent image, and is subjected to a development process or the like in accordance with the photosensitive material and output as a print. In addition to the printer 16, the image data processed by the processing device 14 of the present invention may be output to a storage medium (drive) such as a floppy disk or an MO and stored in the storage medium.

Although the image processing apparatus of the present invention has been described in detail above, the present invention is not limited to the above embodiment, and various improvements and modifications may be made without departing from the gist of the present invention. Of course.

[0033]

As described above, according to the image processing apparatus of the present invention, the film is read photoelectrically,
In a digital photo printer or the like that performs digital exposure such as light beam scanning, it is not necessary for an operator to perform troublesome work such as clipping of a main part from an image, and an image with a rear blur effect is automatically formed. This makes it possible to easily output a high-value-added print in which a high-quality image is formed between three-dimensional objects and between different depths.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an example of a digital photo printer using an image processing apparatus according to the present invention.

FIGS. 2 (a-1), (a-2), (b-1) and (b-2) are graphs for explaining processing of image data in the image processing apparatus of the present invention.

FIGS. 3A and 3B are graphs for explaining processing of image data in the image processing apparatus of the present invention, respectively.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 (Digital) photo printer 12 Scanner 14 Processing device 16 Printer 18 Detection part 20 Image processing part

Claims (3)

[Claims] 1. A detecting means for receiving image information of two same images having different focus conditions and detecting a main part and a background of the image, and an image of the two images according to the detection result. An image processing apparatus comprising: an image processing unit that performs different image processing on at least one of a main part and a background on information. 2. The image processing apparatus according to claim 1, wherein in the image processing means, the image processing performed on the main part is a sharpening processing, and the image processing performed on the background is a blur processing. 3. The two images, one of which is an image focused on a main part and the other is an image focused on a background,
The image processing apparatus according to claim 1, wherein the detection unit detects a main part and a background of the image using edge components of two images.