Image analysis – Applications – Biomedical applications
Reexamination Certificate
1998-08-31
2003-01-28
Boudreau, Leo (Department: 2621)
Image analysis
Applications
Biomedical applications
C128S922000
Reexamination Certificate
active
06512841
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an image processing system. This invention particularly relates to an image processing system, to which image information input apparatuses and image information output devices are connected. This invention also relates to an improvement in processing of image information in an image processing system. This invention further relates to an image output device.
2. Description of the Prior Art
Various image forming apparatuses (modalities) for diagnosis, in which X-rays, or the like, are utilized, have heretofore been used in the medical field. As such modalities, computed radiography (CR) apparatuses, computed tomography (CT) scanners, magnetic resonance imaging (MRI) apparatuses, and the like, have been used in practice. An image having been formed by each modality is displayed on a cathode ray tube (CRT) display device or is reproduced on film by a laser printer (LP), or the like. The reproduced image is utilized for making a diagnosis, e.g. for investigating the presence or absence of a diseased part or an injury or for ascertaining the characteristics of the diseased part or the injury.
The CR apparatuses are radiation image recording and read-out systems. With the radiation image recording and read-out systems, a radiation image of an object, such as a human body, is recorded on a sheet provided with a layer of a stimulable phosphor (hereinafter referred to as a stimulable phosphor sheet). The stimulable phosphor sheet, on which the radiation image has been stored, is then exposed to stimulating rays, such as a laser beam, which cause it to emit light in proportion to the amount of energy stored thereon during its exposure to the radiation. The light emitted by the stimulable phosphor sheet, upon stimulation thereof, is photoelectrically detected and converted into an electric image signal. Recently the CR apparatuses are widely used in practice. In cases where the CR apparatuses are connected to a network, which will be described later, the CR apparatuses may take on the form of the entire radiation image recording and read-out systems described above or, for example, radiation image read-out apparatuses alone, which can feed the ultimatelly detected image signal (i.e., image information) into the network.
With the rapid advances made in communication technology and computer technology in recent years, various kinds of networks utilizing computers have been built in hospitals. The aforesaid modalities, which were used in the past as stand-alone apparatuses, constitute part of the network as image information input apparatuses. Also, CRT display devices and LP's constitute part of the network as image information output devices.
The image information input apparatuses (the image forming apparatuses) and the image information output devices have heretofore been produced on the assumption that they will be used alone. Therefore, the problems occurred in that there was no compatibility in the form of image information at the time of input and output of the image information between the image information input apparatuses and the image information output devices. However, with the advances made in the networking technology, the problems are solved little by little.
However, even if the compatibility in the form of image information at the time of input and output of the image information between the image information input apparatuses and the image information output devices is established, and a plurality of kinds of image input modalities and a plurality of image information output devices can be connected as the constituent elements of a network, the problems described below will occur. Specifically, even if the image Information input apparatuses are the ones belonging to the same kind of image input modality, each of the image information input apparatuses will have device characteristics, such as response functions [a contrast transfer function (CTF) and a modulation transfer function (MTF)] and gradation characteristics, which are inherent to the manufacturer and the type or the version (the improvement generation number) of the apparatus. Therefore, in cases where two pieces of image information, which have been inputted from two image information input apparatuses belonging to the same kind of image input modality, are fed into a single image information output device, reproduced images having different image quality are obtained for different manufacturers and different types or versions of the image information input apparatuses.
More specifically, for example, a single image input modality, which is classified as CR apparatuses, includes a CR apparatus made by a manufacturer A and a CR apparatus made by a manufacturer B. As illustrated in
FIG. 3A
, the CR apparatus of the manufacturer A has a linear profile of gradation characteristics, i.e., the correspondence relationship between input quantity logE (−2 to +2), which is obtained from logarithmic transform of radiation dose (0.01 mR to 100 mR), and output quantity represented by digital values of 0 to 1,023. On the other hand, as illustrated in
FIG. 3B
, the CR apparatus of the manufacturer B has a non-linear profile of gradation characteristics. Therefore, in cases where two pieces of image information, which are fed respectively from the two CR apparatuses, are the ones representing images of the same object, which images have been recorded under the same image recording conditions, and the two pieces of image information are fed into a single CRT display device and respectively reproduced and displayed on the CRT display device, images having identical gradation characteristics cannot be obtained. The difference in gradation characteristics appears as a difference in impression given by the images, and therefore there is a risk that an accurate diagnosis cannot be made.
The same problems also occur with the image information output devices. Specifically, in cases where a single piece of image information is fed into two or more image information output devices having different output device characteristics, visible images having different gradation characteristics, different frequency characteristics, and the like, and giving different impressions are reproduced by the image information output devices.
More specifically, for example, a single kind of image information output device, which is classified as CRT display devices, includes a CRT display device made by a manufacturer A and a CRT display device made by a manufacturer B. The CRT display device of the manufacturer A may have frequency characteristics which are defined by a response function MTF
out
of a profile shown in FIG.
22
A. The CRT display device of the manufacturer B may have frequency characteristics, which are defined by a response function MTF
out
of a profile shown in FIG.
22
B. In such cases, even if a single piece of image information, which has been obtained with a single CR apparatus and represents an image of an object having been recorded under certain image recording conditions, is fed into the two CRT display device, an image reproduced and displayed on the CRT display device of the manufacturer A and an image reproduced and displayed on the CRT display device of the manufacturer B cannot have identical frequency characteristics. The difference in frequency characteristics appears as a difference in impression given by the images, and therefore there is a risk that an accurate diagnosis cannot be made.
SUMMARY OF THE INVENTION
The primary object of the present invention is to provide an image processing system, wherein at least two pieces of image information, which are received respectively from at least two image information input apparatuses belonging to a single kind of image input modality, are capable of being processed as pieces of image information, which do not depend upon input device characteristics of the image information input apparatuses.
Besides the cases where act least two image information input apparatus
Ogawa Eiji
Shimura Kazuo
Takeo Hideya
Yamada Masahiko
Boudreau Leo
Fuji Photo Film Co. , Ltd.
Tabotabor Abolfazl
LandOfFree
Image processing system 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 system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Image processing system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3052172