Image analysis – Histogram processing – With a gray-level transformation
Reexamination Certificate
2000-02-14
2004-02-17
Chen, Wenpeng (Department: 2624)
Image analysis
Histogram processing
With a gray-level transformation
C382S167000, C382S274000, C358S461000
Reexamination Certificate
active
06694052
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an image reproducing method and apparatus for reproducing a visible image from an image signal, which is obtained from a color image carried on a reflection type of image storage sheet, such as a photograph or printed matter, or a transmission type of image storage sheet, such as negative film or reversal film.
2. Description of the Prior Art
Recently, research of digital photo printers has been carried out. With the digital photo printers, an image having been recorded on photographic film (hereinbelow referred to as the film), such as negative film or reversal film, or on printed matter is photoelectrically read out, and an image signal having thus been obtained is converted into a digital signal. The digital signal is then subjected to various kinds of image processing, and a processed image signal is thereby obtained. Thereafter, recording light is modulated with the processed image signal, and a photosensitive material, such as photographic paper, is scanned with and exposed to the modulated recording light. In this manner, a visible image is printed on the photosensitive material.
With the digital photo printers, layouts of printed images, such as combining of a plurality of images, division of an image, and editing of characters and images, and various kinds of image processing, such as color/image density adjustment, conversion of magnification, and contour emphasis, can be carried out freely. Therefore, prints having been edited and processed freely in accordance with applications of the prints can be obtained. Also, in cases where the conventional surface exposure techniques are employed, the image density information having been recorded on film, or the like, cannot be reproduced perfectly due to limitation imposed upon the reproducible image density range of photosensitive materials. However, with the digital photo printers, prints can be obtained such that the image density information having been recorded on film, or the like, can be reproduced approximately perfectly.
Basically, the digital photo printers are constituted of a read-out means for reading out an image having been recorded on an image storage sheet, such as film, and an image reproducing means. The image reproducing means carries out image processing on the image signal having thus been detected by the read-out means, and adjusts exposure conditions. Also, the image reproducing means carries out a scanning exposure operation on a photosensitive material under the adjusted exposure conditions and carries out development processing on the exposed photosensitive material. Further, the image reproducing means can reproduce a visible image from the image signal having been obtained from the image processing and can display the visible image on a monitor.
For example, in a read-out apparatus for reading out an image having been recorded on film, or the like, wherein slit scanning is carried out, reading light having a slit-like shape extending in a one-dimensional direction is irradiated to the film, and the film is moved in a direction, which is approximately normal to the one-dimensional direction. (Alternatively, the reading light and a photoelectric converting device are moved in the direction, which is approximately normal to the one-dimensional direction.) In this manner, the film is scanned in two-dimensional directions. An image of the light, which has passed through the film and carries the film image information, is formed on a light receiving face of the photoelectric converting device, such as a CCD line sensor, and is thus photoelectrically converted into a light amount signal. The thus detected light amount signal is amplified and is then converted into a digital signal by an analog-to-digital converter. Thereafter, the digital signal is subjected to various kinds of image processing, such as compensation for a fluctuation in the characteristics among the CCD elements of the CCD line sensor, image density conversion, and conversion of magnification, and a processed signal obtained from the image processing is transferred to a reproducing means.
In the reproducing means, for example, a visible image is reproduced from the received image signal and displayed on a display device, such as a cathode ray tube (CRT) display device. When necessary, the operator, who views the reproduced image, corrects the gradation, the color, the image density, or the like, of the reproduced image (i.e., sets the set-up conditions). In cases where the reproduced image is judged as being acceptable as a finished print, the image signal is transferred as the recording image information into a development means or a monitor.
In an image reproducing apparatus, in which the image reproduction with raster scanning (i.e., light beam scanning) is utilized, three kinds of light beams corresponding to exposure of the layers, which are formed on a photosensitive material and are sensitive to three primary colors, e.g. red (R), green (G), and blue (B), are modulated in accordance with the recording image information and deflected in a main scanning direction (which corresponds to the aforesaid one-dimensional direction). Also, the photosensitive material is conveyed in a sub-scanning direction, which is approximately normal to the main scanning direction. (The photosensitive material is thus moved with respect to the deflected light beams and in the sub-scanning direction.) In this manner, the photosensitive material is scanned in two-dimensional directions with the light beams, which have been modulated in accordance with the recording image information, and the image having been read out from the film is thereby reproduced on the photosensitive material.
The photosensitive material having thus been scanned with and exposed to the light beams is then subjected to development processing in accordance with the kind of the photosensitive material. For example, in cases where the photosensitive material is a silver halide photographic material, it is subjected to the development processing comprising the steps of color development, bleach-fix, washing, drying, and the like. A finished print is thereby obtained.
Such a photosensitive material can record a comparatively wide range of luminance of the object. However, the maximum image density on the photosensitive material is limited. Therefore, in cases where a print of a scene having a large difference in luminance is obtained with an ordinary printing technique, details become imperceptible due to insufficient gradation in either one of a bright portion (a highlight) and a dark portion (a shadow) on the print. For example, in cases where a picture of a person is taken against the light, if the picture is printed such that the image of the person may become clear, the bright portion, such as the sky region, will become white and its details will become imperceptible. Also, if the picture is printed such that the bright portion, such as the sky region, may become clear, the image of the person will become black and its details will become imperceptible. In order to solve the problems, a shutting light technique or a masking print technique has heretofore been employed.
With the shutting light technique, an ordinary level of exposure is given to a region having an intermediate level of image density in a scene. Also, a long time of exposure is given selectively to a region, which is considered to become white and the details of which are considered to become imperceptible on the print, by using a perforated blocking sheet. Further, as for a region, which is considered to become black and the details of which are considered to become imperceptible on the print, the exposure time is kept short selectively by using a blocking sheet. In this manner, the print is obtained such that the contrast of each object may be kept appropriate, and the details of the highlight and the shadow may be kept perceptible. A method has been proposed, in which unsharp image film having been photographically formed by the neg
Chen Wenpeng
Fuji Photo Film Co. , Ltd.
LandOfFree
Image reproducing 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 reproducing method and apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Image reproducing method and apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3351660