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Full-Text Articles in Physical Sciences and Mathematics
Performance Evaluation Of Hybrid Coding Of Images Using Wavelet Transform And Predictive Coding, S. R. Subramanya, Chaman Sabharwal
Performance Evaluation Of Hybrid Coding Of Images Using Wavelet Transform And Predictive Coding, S. R. Subramanya, Chaman Sabharwal
Computer Science Faculty Research & Creative Works
Image compression techniques are necessary for the storage of huge amounts of digital images using reasonable amounts of space, and for their transmission with limited bandwidth. Several techniques such as predictive coding, transform coding, subband coding, wavelet coding, and vector quantization have been used in image coding. While each technique has some advantages, most practical systems use hybrid techniques which incorporate more than one scheme. They combine the advantages of the individual schemes and enhance the coding effectiveness. This paper proposes and evaluates a hybrid coding scheme for images using wavelet transforms and predictive coding. The performance evaluation is done …
A Systolic Image Difference Algorithm For Rle-Compressed Images, Fikret Erçal, Mark Allen, Hao Feng
A Systolic Image Difference Algorithm For Rle-Compressed Images, Fikret Erçal, Mark Allen, Hao Feng
Computer Science Faculty Research & Creative Works
A new systolic algorithm which computes image differences in run-length encoded (RLE) format is described. The binary image difference operation is commonly used in many image processing applications including automated inspection systems, character recognition, fingerprint analysis, and motion detection. The efficiency of these operations can be improved significantly with the availability of a fast systolic system that computes the image difference as described in this paper. It is shown that for images with a high similarity measure, the time complexity of the systolic algorithm is small and, in some cases, constant with respect to the image size. A formal proof …
A Model-Based Approach For Compression Of Fingerprint Images, Fikret Erçal, M. Gokmen, Ilker Ersoy
A Model-Based Approach For Compression Of Fingerprint Images, Fikret Erçal, M. Gokmen, Ilker Ersoy
Computer Science Faculty Research & Creative Works
We propose a new fingerprint image compression scheme based on the hybrid model of an image. Our scheme uses the essential steps of a typical automated fingerprint identification system (AFIS) such as enhancement, binarization and thinning to encode fingerprint images. The decoding process is based on reconstructing a hybrid surface by using the gray values on ridges and valleys. In this compression scheme, the ridge skeleton is coded efficiently by using differential chain codes. The valley skeleton is derived from the ridge skeleton and the gray values along the ridge and valley skeletons are encoded using the discrete cosine transform. …
Systolic Algorithm For Processing Rle Images, Hao Feng, Fikret Erçal, Filiz Bunyak
Systolic Algorithm For Processing Rle Images, Hao Feng, Fikret Erçal, Filiz Bunyak
Computer Science Faculty Research & Creative Works
Image difference operation is commonly used in on-line automated printed circuit board (PCB) inspection systems as well as many other image processing applications. In this paper, we describe a new systolic algorithm and its system architecture which computes image differences in run-length encoded (RLE) format. The efficiency of this operation greatly affects the overall performance of the inspection system. It is shown that, for images with a high similarity measure, the time complexity of the systolic algorithm is a small constant. A formal proof of correctness for the algorithm is also given in the paper.