Facsimile and static presentation processing – Static presentation processing – Attribute control
Reexamination Certificate
1999-05-20
2004-06-08
Lee, Thomas D. (Department: 2724)
Facsimile and static presentation processing
Static presentation processing
Attribute control
C382S260000
Reexamination Certificate
active
06747757
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to an image processing method and apparatus, more particularly, to an image processing apparatus for compensating a deterioration of an image quality of an image representing image data, which occurs due to lens characteristics, for the image data of the image obtained by reading a recording material on which the image is projected and recorded through a lens. More specifically, the present invention relates, in a digital photo printer, etc. for obtaining digital image data by photoelectrically reading an image photographed on a film or an image directly as digital image data by photographing with an image pickup device and a print (photograph) reproducing the thus obtained image as digital image data, to an image processing method and apparatus based on a technical field of compensating aberrations such as a transverse chromatic aberration and a distortion aberration due to a photographic lens, which occur in an image captured by a lens-attached film, an inexpensive compact camera, or a digital camera, etc.
Currently, printing on a photosensitive material (photographic printing paper) an image photographed on a photographic film such as a negative film and a reversal film (hereinafter referred to as a film), has been executed by a so-called direct exposure (analog exposure) of exposing a surface of the photosensitive material to the light by projecting the film image upon the photosensitive material.
By contrast, there has been hitherto also known an image processing system in which for image data obtained by reading a film image recorded on a photographic film or image data inputted from a digital camera, etc., after performing various image processes, it is capable of outputting the image in various output forms such as recording the image to a recording material, e.g., a photographic printing paper, displaying the image on display means, e.g., a display, and storing the image data into an information recording medium. According to this image processing system, as compared with the conventional photographic processing system for recording the film image to the photographic printing paper through the surface exposure, an image quality of output image from the image processing system can freely be controlled by the image processing for the image data, so that the output image having a high quality can be realized.
That is, in this image processing system, there has been in recent years utilized a printing apparatus that makes use of a digital exposure, i.e., a digital photo printer for obtaining a (finished) print by photoelectrically reading an image recorded on the film, converting the read image into digital signals, thereafter conducting a variety of image processing on the digital signals to thereby acquire output image data for recording, and recording the image (latent image) by scan-exposing the photosensitive material to recording light modulated in correspondence with the output image data.
The digital photo printer is capable of converting the image into digital image data and determining an exposure condition upon printing through the image data processing and is therefore able to obtain a high-definition print, which could not be acquired so far by the prior art direct exposure method, by preferably compensating a white compression and a black compression which might be attributed to back light and flash photography, etc., executing a sharpness (sharpening) process, compensating a failure in terms of shortage of a peripheral light quantity and the like.
In case that a distortion occurs in the image photographed and recorded on the film, however, the image quality of the output image outputted as a photo print cannot often be improved by performing the above-mentioned compensation. As the cause of the image distortion, there might be exemplified a transverse chromatic aberration and a distortion aberration arisen from a lens performance attached to the camera that has photographed the image.
A color image is formed by three primary colors of red (R), green (G), and blue (B). Since indexes of refraction (image forming magnifications) of the lens are fine different by a wavelength, the image forming magnifications of R, G, and B lights are various, namely, the transverse chromatic aberration occurs. As a result, if the image photographed on the film is reproduced, a color deviation is caused to the obtained image.
In order to acquire a preferable photographed image, it is necessary that with respect to a plane vertical to an optical axis, an image is formed on the image-forming surface corresponding to it. However, as for a normal lens, the image-forming position deviates in the optical axis direction and a distortion, that is, a distortion aberration is caused in the image-formed image, so that when the image photographed on the film is reproduced, the obtained image is distorted.
In case of using a camera for which costs to some degree might be increased such as a single lens reflex camera, by using a lens having a high precision and further by combining a plurality of lenses, various aberrations such as a transverse chromatic aberration and a distortion aberration are compensated and thereby enabling a proper image to be photographed on the film. Nevertheless, a lens-attached film or a compact camera, etc. might be severely restricted in terms of cost for the lens, with a result that the transverse chromatic aberration and distortion aberration are caused in the image photographed on the film. The image reproduced as a print might accordingly have distortions.
To solve the problem of the image quality deterioration that the image quality of the output image outputted as a photo print cannot be improved, techniques in relation to an image processing method of and an image processing apparatus for compensating an aberration of the image according to lens aberration characteristics obtained through lens information obtaining means have been disclosed in Japanese Patent Application Laid-Open No. Hei 6-311425 and Japanese Patent Application Laid-Open No. Hei 9-281613 (Japanese Patent Application No. Hei 8-92804). It is pointed out that by those techniques, aberrations due to a lens can be compensated, a deterioration of image quality in periphery of the image can be prevented, and thus an image having a high quality always can be acquired.
As mentioned above, yet, the lens of the lens-attached film is generally constructed by an inexpensive plastic lens, so that the aberrations such as a distortion aberration and a transverse chromatic aberration are large and in the film image exposed and recorded on the photographic film by the lens-attached film, a geometric distortion due to the lens distortion aberration and a color blur due to the lens transverse chromatic aberration occur relatively remarkably. Incidentally, with regard to the lens of the lens-attached film, a so-called drop in light quantity (decrease in light) in the periphery conspicuously occurs and there is also a problem that in the film image exposed and recorded on the photographic film by the lens-attached film, lightness in periphery of the image is more largely decreased than that in the center portion of the image. In the foregoing image processing system, hence, to obtain an output image having a high quality from the above-mentioned image, there is underway an examination of a contrivance that a distortion aberration compensation for compensating the geometric distortion in the image due to the lens distortion aberration, transverse chromatic aberration compensation for compensating the color blur in the image due to the lens transverse chromatic aberration, or a peripheral light decrease compensation for compensating the decrease in lightness in the periphery of the image due to drop in light in the periphery of the lens is executed.
The distortion aberration compensation can be performed as follows. When, for instance, an inherent position (lattice point position) of each pixel constituting a film image is set as a reference, distortion
Birch & Stewart Kolasch & Birch, LLP
Brinich Stephen
Lee Thomas D.
LandOfFree
Image processing method and apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Image processing method and apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Image processing method and apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3323557