Patent application number | Description | Published |
20090003601 | ALPHA-MASKED IMAGE MATCHING - A method and system is disclosed for authenticating a physical medium ( | 01-01-2009 |
20090021551 | METHOD OF MEASURING PRINTER CHARACTERISTICS | 01-22-2009 |
20090021552 | METHOD OF MEASURING PRINTER CHARACTERISTICS | 01-22-2009 |
20090161945 | Geometric parameter measurement of an imaging device - Disclosed is a method of determining at least one three-dimensional (3D) geometric parameter of an imaging device. A two-dimensional (2D) target image is provided having a plurality of alignment patterns. The target image is imaged with an imaging device to form a captured image. At least one pattern of the captured image is compared with a corresponding pattern of the target image. From the comparison, the geometric parameter of the imaging device is then determined. The alignment patterns include at least one of (i) one or more patterns comprising a 2D scale and rotation invariant basis function, (ii) one or more patterns comprising a 1D scale invariant basis function, and (iii) one or more patterns having a plurality of grey levels and comprising a plurality of superimposed sinusoidal patterns, the plurality of sinusoidal patterns having a plurality of predetermined discrete orientations. Also disclosed is a two-dimensional test chart for use in testing an imaging device, the test chart comprising a plurality of alignment patterns, at least one of said alignment patterns including one of those patterns mentioned above. | 06-25-2009 |
20100156987 | METHOD OF MEASURING PRINTER SPATIAL CHARACTERISTICS | 06-24-2010 |
20100157047 | MEASURE DISPLAY SFR USING A CAMERA AND PHASE SHIFTING - A method for measuring the spatial frequency response (SFR) of an imaging system ( | 06-24-2010 |
20130063566 | DETERMINING A DEPTH MAP FROM IMAGES OF A SCENE - A technique determines a depth measurement associated with a scene captured by an image capture device. The technique receives at least first and second images of the scene, in which the first image is captured using at least one different camera parameter than that of the second image. At least first and second image patches are selected from the first and second images, respectively, the selected patches corresponding to a common part of the scene. The selected image patches are used to determine which of the selected image patches provides a more focused representation of the common part. At least one value is calculated based on a combination of data in the first and second image patches, the combination being dependent on the more focused image patch. The depth measurement of the common part of the scene is determined from the at least one calculated value. | 03-14-2013 |
20130266210 | DETERMINING A DEPTH MAP FROM IMAGES OF A SCENE - Methods for determining a depth measurement of a scene which involve capturing at least two images of the scene with different camera parameters, and selecting corresponding image patches in each scene. A first approach calculates a plurality of complex responses for each image patch using a plurality of different quadrature filters, each complex response having a magnitude and a phase, assigns, for each quadrature filter, a weighting to the complex responses in the corresponding image patches, the weighting being determined by a relationship of the phases of the complex responses, and determines the depth measurement of the scene from a combination of the weighted complex responses. | 10-10-2013 |
20130279805 | IMAGE RESAMPLING BY FREQUENCY UNWRAPPING - A method determines at least one image value of a corresponding desired output position of an output image from an input image. An orientation of an edge passing through the output position is determined in a localised region of the input image. A frequency spectrum for the region of the input image is extended. A main frequency band of the edge is aligned in the extended frequency spectrum parallel to a first sampling axis of a grid based on the orientation of the edge. The grid is selected from a set of the input and output grids. The aligned main frequency band is filtered along a second sampling axis of the grid, orthogonal to the first sampling axis, the filter removing frequencies associated with replica bands and maintaining the main frequency band. The image value is determined from the filtered edge at the desired output position. | 10-24-2013 |
20140152886 | BOKEH AMPLIFICATION - A method of modifying the blur in at least a part of an image of a scene captures at least two images of the scene with different camera parameters to produce a different amount of blur in each image. A corresponding patch in each of the captured images is selected each having an initial amount of blur is used to calculate a set of frequency domain pixel values from a function of transforms of the patches. Each of the pixel values in the set are raised to a predetermined power, forming an amplified set of frequency domain pixel values. The amplified set of frequency domain pixel values is combined with the pixels of the patch in one of the captured images to produce an output image patch with blur modified relative to the initial amount of blur in the image patch. | 06-05-2014 |
20140153692 | Combining Differential Images by Inverse Riesz Transformation - A method forms a representative image from a crossed grating fringe pattern interferogram of an object from an interferometer. The method determines a plurality of spectral lobes from the interferogram and selects from the plurality of determined lobes, two substantially orthogonal sidelobes. The selected sidelobes represent spatial differential phase information of the interferogram. The method applies an inverse Riesz transform to the spatial differential phase information of the selected sidelobes to form a transformed differential phase image, and forms from the transformed differential phase image, a representative image emphasising high frequency detail information of the object. | 06-05-2014 |
20140177790 | Non-linear solution for 2D phase shifting - Disclosed is a method of reconstructing a representative detailed phase image from a set of fringe pattern interferogram images of an object. The images are captured by an x-ray interferometer having a crossed diffraction grating. A set of captured fringe pattern interferogram images from the x-ray interferometer are provided, the set comprising no more than eight captured fringe pattern interferogram images. The method determines an estimate of an absorption parameter (a), two-dimensional amplitude modulation parameters (m | 06-26-2014 |
20140369623 | Estimating phase for phase-stepping algorithms - A method of determining an actual phase offset of a fringe pattern in a captured image. A captured image, having a phase modulated fringe pattern, is one of a set of images captured with varying introduced phase offset and forms an intermediate demodulation image from the captured image. The intermediate demodulation image defines amplitude and complex phase parameters of the phase modulated fringe pattern. The captured image is transformed by a mask to produce a processed captured image having reduced effects of phase distortion. The mask is estimated from a function of at least one of the amplitude and complex phase parameters defined by the intermediate demodulation image. The method determines a Fourier transform of the processed captured image, and determines at least one phase offset of the fringe pattern in the processed captured image using the mask to identify interaction of peaks in the Fourier transform. | 12-18-2014 |