A method and system implements a high addressability characteristic into an error diffusion process. A histogram of the image is generated and the actual background and black reference values are determined. A gray level value representing a pixel is received. The gray level value has a first resolution which corresponds to an original input resolution. The gray level value is interpolated to generate subpixel gray level values which correspond to a second resolution. The second resolution is hi...

A computerized methodology for reducing swath scanner swath boundary discontinuities is provided by using a predetermined overlap of pixel rows during each sequential scan. Pixel data from a first scan of the overlapped pixel rows is compared to the pixel data from a second scan of the overlapped pixel rows, identical pixels of the overlapped pixel rows ideally having the same representative scan data. Errors are compensated by weighting representative scan data for each pixel row, linearly decr...

Disclosed is a method, system, and program for converting an externally defined four dimensional colorant, e.g., CMYK, to an equivalent four dimensional colorant, e.g., C'M'Y'K, having components of a printer. A measurement is made of first color values, e.g., L.sup.* a.sup.* b, of a first set of patches having predetermined combinations of varying percentages of three primary colors, e.g., CMY, printed by the printer. Each combination of known CMY values are correlated with corresponding color ...

A decoder for converting packet data into raster data is provided. The packet data includes data about a picture-compressed video signal and data about a picture format including a picture rate. The decoder comprising a first processing means, second processing means and a storage means. The first processing means converts the packet data into intermediate data such that picture compression is eliminated from the picture-compressed video signal and outputs the intermediate data. The second proce...

Color printing systems frequently use multiresolution analysis, which creates intermediate lower resolution images, in applications such as descreening and filtering. The typical steps are to decompose the original image into sub bands, apply the application to one or more sub bands and then recompose the image, prior to color correction and color space transformation. This disclosure describes applying the color correction to one of the lower resolution sub bands and a simpler color space trans...

A method and apparatus for color calibrating an imager device is disclosed. The imager device is subjected to a plurality of light sources. Color channel responses are obtained from the imager device and the color calibrating coefficients are determined.

A texture-based text localization system proceeds directly in the compressed domain for DCT compressed JPEG images or MPEG videos. The DCT coefficient values in JPEG images and MPEG videos, which capture the directionality and periodicity of local image blocks, are used as texture feature measures to classify text areas. Each unit block in the compressed images is classified as either text or nontext. In addition, post-processing in both the compressed domain and the reconstructed candidate text...

The image compression and expansion device comprises a recording medium, in which compressed image data, which are obtained by applying an Hadamard's transformation, a quantization and an encoding to original image data, and a quantization table are recorded. The compressed image data are decoded by a decoding unit. The decoded image data are dequantized by the quantization table. The dequantized image data are converted to corrected dequantized image data, which are then subjected to an inverse...

Recently, a number of reversible wavelet transforms have been identified which allow for exact reconstruction in integer arithmetic. Different transforms vary in how rounding is performed. The present invention provides a transform, which is linear except for the rounding with non-linear operations in order to create a reversible implementation. Also, the present invention also provides transforms which are decomposed into all FIR parts.

The invention relates to a method and an apparatus for the analysis and correction of colour casts in a digitally represented image. According to a preferred embodiment, the crominance contents of the image may be transformed by use of a Hough-transformation or the like transformation, wherein the line structures in the carthesic system of co-ordinates for the crominance content is transformed to a representation in a Hough-diagram in the form of a polar system of co-ordinates, since such line s...