Koh Kamizawa

Sound processing apparatus capable of correct and efficient extraction of significant section data

Input sound information is converted to digital sound data, and characteristic parameter values are extracted from the digital sound data. Based on the characteristic parameter values, a judging unit produces a judgement result indicating whether the current section is a significant or insignificant section and its continuation length. If the continuation length is shorter than the predetermined length, a correcting unit reverses the judgment of whether the current section is a significant or insignificant section and sums up the continuation length of the current section and continuation lengths of the adjacent sections, to thereby produce a single section data.

Object-oriented color management system

Color management system (CMS) plays an important role in color image processing systems to maintain consistent color appearance among various devices on a network. Considering a network environment, the conventional CMS depends deeply on the configuration of the network and the system. This paper describes an object-oriented CMS architecture and its implementation strategy for a distributed environment name Network CMS (NCMS). NCMS can keep the consistency of the device profiles and needs not to be installed on all the work stations on a network. The discussion of the effectiveness of NCMS shows that it suits well for color management on a distributed system due to its object-oriented features and the Client- Server model implementation. This system will be a good test bed to explore advanced color document processing systems and future color interchange facilities.

Encoding of pictures using the singular value decomposition (SVD) and 1-D discrete cosine transform (DCT)

We propose an efficient encoding algorithm which decomposes a picture matrix A to singular values and eigen vectors of AA/sup T/ and A/sup T/A, and then encodes the singular values and DCT coefficients of eigen vectors by PCM. We transform the eigen vectors of the first decomposed term, which are flat and do not have higher frequency components, to 1 dimensional DCT coefficients. The magnitude of the coefficients is small when the vector is flat, allowing us to encode the coefficients efficiently using this characteristic. For decomposed terms other than the first decomposed term, we are able to encode the singular values and eigen vectors by PCM with a small number of bits without increasing quantization noise, since the singular values are very small.

Study for high-resolution color-image-coding approach for office system

Distributed office systems employ the image exchange facilities such as image input/output, handling a softcopy, image filing service and so on. This paper presents a study of the segmented image exchange approach suit well for block based image coding and image processing schemes. From the result of the feasibility study, the segmented image formatting criterion provides a well-designed quantization-table set for DCT coding scheme. The 400 spi full-tone image coding simulation of the segmented adaptive quantization for DCT coding shows the better SNR and the perceptually better image quality than that of the conventional scheme. To select the quantization-table in the decoder, this scheme requires 3-bit header for every coded block. However, it enables another image processing features in a reconstructed image.

High-resolution color image transmission scheme over ATM network

This paper describes a system that attaches a color copier to ATM network as a full color image input and output terminal. For still image tranmission, both high quality of the transmitted image and high transmission throughput are required. To achieve this goal, a new image transmission scheme for ATM network is proposed. A design and implementation of a protocol based on the scheme, an image tranmission system and evaluation of its throughput are also discussed. The scheme is based on retransmission with allowing limited number of errors for one block of data. Instead of retransmission, the scheme employs concealment for the cases of small number of errors. Concealment is an error correction method using the redundancy of image data to improve image data quality. The system based on this scheme demonstrated throughput as almost high as the maximum bandwidth of ATM, 156Mbps, with keeping image quality better than 40dB. It is proved that a relaxation of retransmission condition by concealment is effective to achieve high throughput under average ATM netowrk transmission quality. The system can provide 20 pages per minute transmission throughput for 16 pixels/mm resolution full color images.

High-resolution color image coding scheme for office systems

There is great interest in having office systems that adopt the image coding to enable high resolution and high quality document management. Network-based office systems require two classes of procedures. The first requires a new “ internal coding” scheme for integrated image processing and editing operations. The second corresponds to image data interchange between system components through the network and can be implemented using conventional image coding scheme such as JPEG. This paper deals with a new image coding scheme which is designed for internal coding facility based on the adaptive block truncation coding. This scheme can perform block by block fixed rate coding and editing within an encoded form. The simulation results show the feasibility of the proposed scheme at compression ratios of 4 to 8.