Abstract: An image interpolating device comprises a color filter, in which R, G, and B color filter elements are disposed in a checkerboard arrangement, and an imaging device which generates R, G, and B-signals corresponding to the color filter elements. In an interpolation process, the differences between a G-signal of an objective pixel and G-signals of pixels adjacent to the right, left, upper, and lower sides of the objective pixel are checked. For example, if the G-signal of the left side pixel is the closest to that of the objective pixel, a luminance value Y, a color difference signal Cb, and a modified luminance signal YG of the objective pixel are obtained using the R, G, and B-signals of the left side pixel. A B-signal of the objective pixel is obtained using the modified luminance value YG, and the color difference signal Cb.

Abstract: An image compression and expansion apparatus reproduces an expanded image corresponding to an original image from a reduced image. The original image data is comprised of approximately 1000×600 pixel values Pyx. A first matrix M1 comprised of 64×64 pixel values Pyx is extracted from the original image data. Regarding the original image data arranged in the first matrix M1, an average value of 8×8 pixel values Pyx forming a block B1 is obtained, and thus a second matrix M2 is generated using the average value as a single pixel value. The pixel values of the second matrix M2 is subject to two dimensional discrete cosine transformation to obtain a matrix MD comprised of 8×8 DCT coefficients. Expanded two dimensional inverse discrete cosine transformation is applied to the matrix MD to obtain a third matrix M3 comprised of 64×64 pixel values. The expanded image data comprising the third matrix M3 is transformed to the same coordinate system as the original image data and recorded on to the recording medium.

Abstract: A color chart for a color adjustment of a color printer and a color monitor attached to an endoscope, has first-, second-, and third-color cell groups. The first-, second-, and third-color cell groups have respective first, second, and third predetermined numbers of color cells which have the same form, and which are linearly arranged in a first direction. The first-, second-, and third-color cell groups are arranged in a second direction which is perpendicular to the first direction.

Abstract: A color chart for a color adjustment of a color printer and a color monitor attached to an endoscope, has a predetermined number of color cells. The color cells have the same form, and are arranged in one of a grid state and a linear state. Each of the color cells is formed by blending two colors from a group of three colors comprising red, green, and blue, according to a predetermined ratio, in an additive color process. The color cells show a gradation of color such that a color tone of each of the color cells changes continuously in one direction.

Abstract: An image interpolating device comprises a color filter, in which R, G, and B color filter elements are disposed in a checkerboard arrangement, and an imaging device which generates R, G, and B-signals corresponding to the color filter elements. In an interpolation process, the difference between a first comparative value V1 and a second comparative value V2 is compared. V1 is determined using color signals of pixels offset in the right and left directions to an objective pixel. V2 is determined using color signals of pixel offset in the upper and lower directions to the objective pixel. When V1 is less than V2, an arithmetic mean of G-signals of pixels offset in the right and left directions by one pixel is obtained as an interpolated G-signal. When V1 is not less than V2, an arithmetic mean of G-signals of pixels offset in the upper and lower directions by one pixel is obtained as the interpolated G-signal.

Abstract: An image compression and expansion apparatus obtains an average value of a single block (8×8 pixels) in a first matrix (64×64 pixels) of the original image data, to generate reduced image data of a second matrix (8×8 pixels). A sub-matrix, which is displaced from the second matrix by a predetermined amount, is obtained in such a manner that a pixel of the second matrix is contained in the sub-matrix. 8×8 pixels of the sub-matrix are subjected to a two dimensional discrete cosine transformation, to obtain reduced DCT coefficient data. The reduced DCT coefficient data is subjected to an expanded inverse discrete cosine transformation to obtain expanded image data of a matrix (64×64 pixels). The displacement direction and the displacement amount of the sub-matrix relative to the second matrix are selected in such a manner that the expanded image data becomes as close to the original image data as possible.

Abstract: An image compression and expansion apparatus obtains an average value of a single block (8×8 pixels) in a first matrix (64×64 pixels) of the original image data, to generate reduced image data of a second matrix (8×8 pixels). A sub-matrix, which is displaced from the second matrix by a predetermined amount, is obtained in such a manner that a pixel of the second matrix is contained in the sub-matrix. 8×8 pixels of the sub-matrix are subjected to a two dimensional discrete cosine transformation, to obtain reduced DCT coefficient data. The reduced DCT coefficient data is subjected to an expanded inverse discrete cosine transformation to obtain expanded image data of a matrix (m×n pixels). The displacement direction and the displacement amount of the sub-matrix relative to the second matrix, and the values of “m” and “an” are selected in such a manner that the expanded image data becomes as close to the original image data as possible.

Abstract: An image compression apparatus transforms original image data partitioned into first blocks, each of which is composed of a plurality of pixels, to reduced-image data composed of a smaller number of pixels than that of the original image data. Further, the apparatus generates expanded-image data from the reduced-image data by fluency transform. Based on the expanded-image data and the original image data, differential value data is obtained, and the differential value is transformed to differential DCT coefficient data by DCT processing. Based on the differential DCT coefficient data, a code-length corresponding to a bit-length necessary for a Huffman coding is calculated. The fluency transform has a plurality of modes, each mode being selected in order, the code-length being calculated for all of the modes. Then, a mode which makes the code-length minimum is determined as the optimum mode. The differential DCT coefficient data is Huffman encoded, so that Huffman-encoded bit data is generated.

Abstract: A compression apparatus transforms original image data partitioned into first blocks, each of which is composed of a plurality of pixels, to reduced-image data composed of a smaller number of pixels than that of the original image data. The reduced-image data is subjected to a fluency transform to generate expanded-image data partitioned into second blocks corresponding to the first blocks. The fluency transform has a plurality of modes, and one mode is selected from the plurality of modes, thus the expanded-image data is generated in accordance with the selected one mode. An error, which represents a difference between the original image data and the expanded-image data, is calculated in each of the plurality of modes. Then, an optimum mode, by which the error becomes a minimum value, is determined among the plurality of modes. On the other hand, an expansion apparatus generates the expanded-image data by applying the fluency transform using the optimum mode.

Abstract: An expanded-image generating apparatus is provided for original image data, in which a plurality of pixels is arranged in a matrix, so as to obtain expanded-image data partitioned into a plurality of blocks, each of which is composed of a plurality of pixels When the magnifying power regarding at least one of a direction along width and a direction along length in the original image data is set, a pixel arranging processor arranges each pixel in the original image data at a position corresponding to a center position of each of the plurality of blocks in accordance with the magnifying power. The expanded-image data corresponding to the magnifying power is generated at pixel generating positions corresponding to the each block by applying a fluency transform to each pixel in the original image data at the position.

Abstract: The image compression and expansion device handles pixel data (R, G, B) which are generated according to the 256-color mode. The pixel data are compressed and recorded in a recording medium. Palette information, composed of color data of the 256-color mode, are converted to data which are conformed to a predetermined format, and are recorded in the recording medium. The compressed image data and the palette information, which are recorded in the recording medium, are read therefrom, so that the compressed image data are expanded to reproduce the pixel data. In this expansion process, based on the reproduced pixel data, color data, which correspond to the pixel data and are contained in the palette information, are selected.

Abstract: An image interpolating device comprises a color filter, in which R, G, and B color filter elements are disposed in a checkerboard arrangement, and an imaging device which generates R, G, and B-signals corresponding to the color filter elements. In an interpolation process, the difference between a first comparative value V1 and a second comparative value V2 is compared. V1 is determined using color signals of pixels offset in the right and left directions to an objective pixel. V2 is determined using color signals of pixel offset in the upper and lower directions to the objective pixel. When V1 is less than V2, an arithmetic mean of G-signals of pixels offset in the right and left directions by one pixel is obtained as an interpolated G-signal. When V1 is not less than V2, an arithmetic mean of G-signals of pixels offset in the upper and lower directions by one pixel is obtained as the interpolated G-signal.

Abstract: An image interpolating device comprises a color filter, in which R, G, and B color filter elements are disposed in a checkerboard arrangement, and an imaging device which generates R, G, and B-signals corresponding to the color filter elements. In an interpolation process, the differences between a G-signal of an objective pixel and G-signals of pixels adjacent to the right, left, upper, and lower sides of the objective pixel are checked. For example, if the G-signal of the left side pixel is the closest to that of the objective pixel, a luminance value Y, color difference signals Cb and Cr, and a modified luminance signal YG of the objective pixel are obtained using the R, G, and B-signals of the left side pixel. Regarding the objective pixel, a B-signal is obtained and the G-signal is modified, using the modified luminance value YG, and the color difference signals Cb and Cr.

Abstract: An image interpolating device comprises a color filter, in which R, G, and B color filter elements are disposed in a checkerboard arrangement, and an imaging device which generates R, G, and B-signals corresponding to the color filter elements. In an interpolation process, the differences between a G-signal of an objective pixel and G-signals of pixels adjacent to the right, left, upper, and lower sides of the objective pixel are checked. For example, if the G-signal of the left side pixel is the closest to that of the objective pixel, a luminance value Y, a color difference signal Cb, and a modified luminance signal YG of the objective pixel are obtained using the R, G, and B-signals of the left side pixel. A B-signal of the objective pixel is obtained using the modified luminance value YG, and the color difference signal Cb.

Abstract: An image compression device to compress a still image comprises a DCT processing circuit, a quantization processing circuit, a bit separation processing circuit, a grouping circuit, and an encoding processing circuit. In the bit separation processing circuit, quantized DCT coefficients are subjected to a bit separation processing, such that higher-rank quantized DCT coefficients and lower-rank quantized DCT coefficients are obtained. Thus, a total bit number (length) of compressed image data is decreased. An image expansion device to expand the compressed image data comprises a decoding processing circuit, an inverse grouping circuit, a bit synthesis processing circuit, a dequantization processing circuit, and an IDCT processing circuit. In the bit synthesis processing circuit, the higher-rank quantized DCT coefficients and the lower-rank quantized DCT coefficients are subjected to a bit synthesis processing, such that the quantized DCT coefficients are obtained.

Abstract: An arbitrary-shape image-processing device comprises a CCD by which a two-dimensional image is obtained. The image may be rectangular, and a contour of an image area contained in the image may be a circle. Pixel values contained in the image area are converted to a one-dimensional data array, and are recorded in a recording medium. Further, the numbers of pixels of the vertical and the lateral lengths of the two-dimensional image, the coordinates of the center of the circle of the image area, and the radius of the circle are recorded in the recording medium as shape information. Thus, all of the image data of the two-dimensional image is not recorded in the recording medium, but only the image data contained in the image area and the shape information are recorded.

Abstract: A matching device comprises a monitor screen on which first and second images containing a common object are indicated. First, an arbitrary pixel, contained in the first image, is designated as a designating point. Then, four optimum searching pixels are selected from the first image. The optimum searching pixels exist close to the designating point, and have a pixel value more different from the designating point than pixel values of the other pixels around the optimum searching pixels. A candidate point and candidate point surrounding pixels, which correspond to the designating point and the optimum searching pixels, are detected in the second image.

Abstract: The image compression and expansion device comprises: a DCT processing unit in which original image data is subjected to a two-dimensional discrete cosine transformation to obtain DCT coefficients;a quantization process unit in which the DCT coefficients are quantized by a normal mode quantization table to obtain quantized DCt coefficients; and a compression processing unit in which the quantized DCT coefficients are encoded to generate compressed image data. The compressed image data is recorded in a compressed image data recording area. A security mode quantization table is recorded in a first table recording area which is accessed in a usual expansion process. A normal mode quantiation table is recorded in a second table recording area which is not accessed in the normal expansion mode.

Abstract: 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 Hadamard's transformation, so that reproduced image data are generated. The quantization table is composed of quantization coefficients, each of which is to the power of 2.

Abstract: The image compression and expansion device handles red (R), green (G) and blue (B) image data, which are offset horizontally to each other by one-third of one pixel, for example. The R, G and B image data are converted to a luminance signal and color difference signals, which are compressed according to the JPEG algorithm to generate compressed image data. The compressed image data are then recorded in a recording medium. Offset information, indicating that the R, G and B image data are offset to each other, is converted to a predetermined format, and is also recorded in the recording medium.