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This paper presents a new region-adaptive printing quality enhancement algorithm for mixed scanning documents. To adapt a variety of line-per-inch (LPI) printing documents, novel pixel-wise LPI estimation is done via hadamard transform-based local frequency components analysis. Then, each pixel is classified into either flat-region or edge-region by comparing edge-region representative frequency peak power value and its corresponding flat-region representative frequency peak power value. After, LPI region adaptive-halftone-noise smoother and least square optimal restoration filter enhance the quality of scanned documents. Experimental results indicate that the proposed one provides outperforms other state of the art noise reduction methods on a variety of LPI documents.

This paper presents a new line-per-inch (LPI) adaptive descreening algorithm for restoring a high-quality image when scanning a printed matter. The LPI of scanned image is estimated and image region is classified into flat or edge region by analyzing the distribution in Hadamard transform coefficients. Then, an LPI adaptive edge preserving filtering is applied to reduce the halftone patterns not only in flat region but also in edge region. Proposed method has hardware-friendly structure without iteration and cascades of filters, and also it needs only integer adder and shift operations. Experimental result shows that the proposed method performs adaptively for a variety of LPI contents.

This paper proposes the new super resolution algorithm for improving the texture of low-quality image. Conventional methods have restored the high-resolution image based on the linear blur model with a variety of priors, which boost the frequency powers of the images while preventing from being noisy or having jagged edges. Previous methods show good performance for restoring the sharp and jagged-free edges. However, in the point of texture, they often fail to restore and result in cartoon-like images. To solve this problem, proposed method focuses on the property of natural textures and tries to create the fine texture from self-image by texture transfer, which modulates the phase of the high-frequency components of image in spatial and frequency domains. The sign of DCT coefficients are modulated to change the phase of image in frequency domain, and the high-frequency components of image are reshaped with an auto regressive filter in spatial domain. Moreover, the external noise sources are added to enhance the pixel-precision textures. Experimental results show that the texture of low-quality images is highly improved than that of previous methods. The fine textures created by proposed method give more natural feeling of highresolution image than that of results restored without a consideration of restoring textures.

In this paper, a compact wideband bandstop resonator in the form of open stub combination is proposed. The wideband characteristic of the proposed bandstop resonator is due to electrical coupling at the ends of the two open stubs. A stopband is approximately improved by 52% (rejection depth: -20dB) compared with the case that the end of open stub is uncombined. Proposed structure increases the skirt selectivity and elastically controls the frequency bandwidth and rejection depth.

A compact 24 GHz quadrature Doppler radar front-end module was fabricated using LTCC packaging technology. A method involving the vertical stacking of a three-dimensional LTCC packaging module and an FR-4 substrate was developed, and a compact 24 GHz quadrature Doppler radar front-end module was fabricated.

A novel fine grain creation method for Ultra-HighDefinition TeleVision (UHDTV) has been proposed. To make fine grain components, multi-layer super resolution reconstruction and the frequency modulation method are developed. Base and Texture layer of images are fused separately to prevent the loss of texture components in interpolation. After, fine grains are created on up-scaled images. Fine grain creation is composed of two parts, one is diffusion of low frequency components, and the other is generation of aliased high frequency components. Those are added on the up-scaled video with matching weights to enhance the feeling of textures. The proposed method shows a better performance compared to the conventional restoration methods in terms of texture by the experimental results.

A compact bandstop filters (BSF) is presented. The broadside coupled line resonator configuring the bandstop filter is presented, and implemented on the patterned ground and connected to microstrip line by via hole. The various short-circuited broadside coupled line resonators having the identical physical length is also studied. Measurement results seems to have the similar tendency with the calculations on the stepped-impedance open stub and meander line resonator shows the lowest resonant frequency.

Recently, sub-pixel rendered filter is often used as a post processing of graphic contents to reduce the jagging artifacts in displays. However, in a printing system, sub-pixel filtered image yields blurring and jagging artifacts due to the difference of displaying method. In order to prevent artifacts, new edge enhancement method is proposed. Edge region of an image is processed by an adaptive intensity mapping function to reduce the mid-range of intensities that make jagging artifacts in half-toning. Then, a color replacement function is applied to reduce the color fringe artifacts. Experimental results show that the proposed algorithm improves the quality of printed sub-pixel rendered image.

This paper proposes an adaptive video enhancement method for digitally converted analog video. Analog video often has cross-luma artifacts and blurring artifacts by incorrect separation of a composite video signal. Even digital televisions suffer from these artifacts if high definition contents are converted from composite video contents. In order to reduce these artifacts, we trace signal patterns of artifacts and suppress them by using an adaptive linear filter. Moreover, to restore blurred edges of video, we adopt a neural network filter, in which weight coefficients are trained with artifact-free video. Experiments using a number of video sequences show the effectiveness of the proposed algorithm.

This paper addresses the effective implementation of international standard H.263 and MPEG4 codec using a multimedia chip for wireless phone. This idea can be usefully applied to emerging applications of South Korea mobile phone industry such as videophone and camcorder phone.