256results about How to "Reduce image noise" patented technology

An imaging system consisting of a cell-phone with camera as the detection part of an optical train which includes other components. Optionally, an illumination system to create controlled contrast in the sample. Uses include but are not limited to disease diagnosis, symptom analysis, and post-procedure monitoring, and other applications to humans, animals, and plants.

A method of producing lane information for use in a map database is disclosed. In at least one embodiment, the method includes acquiring one or more source images of a road surface and associated position and orientation data, the road having a direction and lane markings parallel to the direction of the road; acquiring road information representative of the direction of said road; transforming the one or more source images to obtain a transformed image in dependence of the road information, wherein each column of pixels of the transformed image corresponds to a surface parallel to the direction of said road; applying a filter with asymmetrical mask on the transformed image to obtain a filtered image; and producing lane information from the filtered image in dependence of the position and orientation data associated with the one or more source images.

The invention discloses a video-based detection and recognition system and a method of vehicles. The system comprises a target characteristic database module, a moving target detection module and a vehicle recognition module. A vehicle sample target characteristic database is built to store data by virtue of the target characteristic database module. After a moving target zone is detected by the moving target detection module, the vehicle recognition module builds a search window and recognizes vehicles. The system and the method resolve the technical problems of poor vehicle distinguishing capability and low distinguishing accuracy of the video-based vehicle detection under the condition of obvious background movement, vehicle adhesion, vehicle occlusion and the like in the prior art. The video-based detection and recognition system and the method of the vehicles have the advantages of excellent vehicle distinguishing capability and high accuracy.

In a method for imaging in digital dental radioscopy making use of a sensor array, the individual image elements of which are smaller than a desired local resolution so that a plurality of image elements forms a respective effective image element, first reference signals, which are generated by the image elements of the sensor array when said sensor array is not exposed to X-radiation, are initially detected. In addition, second reference signals, which are generated by the image elements of the sensor array when said sensor array is exposed to X-radiation, are detected. Subsequently, defective image elements are determined on the basis of the detected first and second reference signals, whereupon an image of an object is produced using exclusively the image elements that have been determined as being non-defective. Furthermore, during production of the image of an object, it can be determined for the object signals detected for the respective image elements whether said image elements have been hit directly by an X-ray quantum. Image elements that have been hit directly by an X-ray quantum are not used for producing the image of the object.

A hand-held 3D ultrasound instrument is disclosed which is used to non-invasively and automatically measure amniotic fluid volume in the uterus requiring a minimum of operator intervention. Using a 2D image-processing algorithm, the instrument gives automatic feedback to the user about where to acquire the 3D image set. The user acquires one or more 3D data sets covering all of the amniotic fluid in the uterus and this data is then processed using an optimized 3D algorithm to output the total amniotic fluid volume corrected for any fetal head brain volume contributions.

Apparatus and methods for fluorescence imaging using radiofrequency multiplexed excitation. One apparatus splits an excitation laser beam into two arms of a Mach-Zehnder interferometer. The light in the first beam is frequency shifted by an acousto-optic deflector, which is driven by a phase-engineered radiofrequency comb designed to minimize peak-to-average power ratio. This RF comb generates multiple deflected optical beams possessing a range of output angles and frequency shifts. The second beam is shifted in frequency using an acousto-optic frequency shifter. After combining at a second beam splitter, the two beams are focused to a line on the sample using a conventional laser scanning microscope lens system. The acousto-optic deflectors frequency-encode the simultaneous excitation of an entire row of pixels, which enables detection and de-multiplexing of fluorescence images using a single photomultiplier tube and digital phase-coherent signal recovery techniques.

X-ray radiation is transmitted through and scattered from an object under inspection to detect weapons, narcotics, explosives or other contraband. Relatively fast scintillators are employed for faster X-ray detection efficiency and significantly improved image resolution. Detector design is improved by the use of optically adiabatic scintillators. Switching between photon-counting and photon integration modes reduces noise and significantly increases overall image quality.

A hand-held 3D ultrasound instrument is disclosed which is used to non-invasively and automatically measure amniotic fluid volume in the uterus requiring a minimum of operator intervention. Using a 2D image-processing algorithm, the instrument gives automatic feedback to the user about where to acquire the 3D image set. The user acquires one or more 3D data sets covering all of the amniotic fluid in the uterus and this data is then processed using an optimized 3D algorithm to output the total amniotic fluid volume corrected for any fetal head brain volume contributions.

Certain embodiments of the present invention provide a system and method for reducing image noise with the use of a minimal error spatiotemporal recursive filter. An input image is filtered both temporally and spatially, producing a temporal output and a spatial output. Both the temporal output and the spatial output are correlated with the input image to produce a temporal correlation output and a spatial correlation output. The temporal correlation output and the spatial correlation output are mixed to generate a selecting signal. The selecting signal directly or indirectly determines the composition. of an output image. The selecting signal may select a portion of the temporal output and a portion of the spatial output to compose an output image. Alternatively, the selecting signal may select either the temporal output or the spatial output to compose an output image.

The invention discloses a CT (Computed Tomography) value correcting method for cone-beam CT. The CT value correcting method comprises the following steps: scanning air, a water phantom and a bone tissue body phantom under different scanning conditions to respectively obtain projection data; reestablishing an image; removing noise and artifacts by adopting a polynomial fitting method based on a template image; selecting a plurality of interested regions and calculating a mean value of an attenuation coefficient and a standard deviation of the attenuation coefficient; obtaining the value range of the attenuation coefficient and taking the attenuation coefficient of maximum occurrence probability; fitting the attenuation coefficients of the air, the water phantom and the bone tissue body phantom under the different scanning conditions with corresponding ideal CT values to obtain respective fitting curves; performing CT scanning and image reestablishment on a scanned material; obtaining a CT value image according to a material attenuation coefficient image and a fitting curve and finishing the CT value correction. According to the CT value correcting method disclosed by the invention, image noise and artifact can be effectively reduced, the reestablished image of single material reaches the uniformity to the great degree, the precision of the attenuation coefficient of the material becomes higher and further high accuracy for the fitting of the curve of the CT value and the material attenuation coefficient is realized.

An image lens assembly includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element and a fifth lens element. The first lens element with positive refractive power has a convex object-side surface. The second lens element has negative refractive power. The third lens element with refractive power is made of plastic material, and has at least one surface being aspheric. The fourth lens element with refractive power is made of plastic material, and has a concave object-side surface and a convex image-side surface, wherein at least one surface of the fourth lens element is aspheric. The fifth lens element with positive refractive power is made of plastic material, and has a convex object-side surface and a convex image-side surface, wherein at least one surface of the fifth lens element is aspheric.

A system and method is provided for estimating the local noise of CT images and denoising the images using a modified non-local means (NLM) algorithm that is adaptive to local variations of noise levels. A strategy for efficiently estimating the local noise of CT images is also described.

Embodiments of the present invention include a method and apparatus for accurate cone beam reconstruction with source positions on a curve (or set of curves). The inversion formulas employed by embodiments of the method of the present invention are based on first backprojecting a simple derivative in the projection space and then applying a Hilbert transform inversion in the image space.

A dodging process which brightens a dark portion sometimes makes noise components contained in an image obtained by an image sensor conspicuous. A gray image generator extracts a luminance component Y of an image, an unsharp image generator generates an unsharp image L on the basis of the luminance component Y, a correction coefficient calculator calculates a correction coefficient g for correcting a brightness difference of the image in accordance with the unsharp image L, a corrector performs a dodging process in accordance with the correction coefficient g, and a noise eliminator eliminates noise of the image in accordance with the correction coefficient g.