We describe an efficient technique that automatically detects duplicated regions in a digital image. This technique works by first applying a principal component analysis to small fixedsize image blocks to yield a reduced dimension representation. This representation is robust to minor variations in the image due to additive noise or lossy compression. Duplicated regions are then detected by le...

In this paper a new image transformation suited for reversible (lossless) image compression is presented. It uses a simple pyramid multiresolution scheme which is enhanced via predictive coding. The new transformation is similar to the subband decomposition, but it uses only integer operations. The number of bits required to represent the transformed image is kept small though careful scaling a...

This paper presents a Lossy image compression technique which is combination of discrete wavelet transform (DWT), Thresholding, Vector Quantization (VQ) and Huffman coding. Proposed method is as follows, First, DWT is performed on the original image then Globle Thresholding technique is applied and resulting coefficients are then vector quantized. VQ indices are Huffman coded to increase the co...

Large amount of medical image sequences are available in various hospitals and medical organizations, which occupies considerable storage space. Hence to reduce the storage space there is a need for compressing medical images. There are several lossy and lossless compression techniques. Using lossy compression the original images are not recovered exactly but using lossless compression techniqu...

1 Abstract The wavelet transform shows a lot of promise in image compression. Very high compression rates are achieved by using wavelet transform prior to quan-tization and entropy coding. This report discusses how wavelets can be used in image compression. This report handles the problem from an engineer's perspective. I am conndent that this report can be used for writing a primitive wavelet ...

Despite over a decade of research and development, medical image compression has not yet been widely implemented on clinical picture archiving and communication systems (PACS). We have developed a prototype interface which incorporates both lossless and lossy compression into a browsing system that enables the efficient use of network and storage resources. Such a system allows an user to quick...

The paper describes an efficient lossy and lossless three dimensional (3D) image compression of hyperspectral images. The method adopts the 3D spatial-spectral hybrid transform and the proposed transform-based coder. The hybrid transforms are that Karhunen-Loève Transform (KLT) which decorrelates spectral data of a hyperspectral image, and the integer Discrete Wavelet Transform (DWT) which is a...

This paper describes a prototype telemedicine system for remote 3D radiation treatment planning. Due to voluminous medical image data and image streams generated in interactive frame rate involved in the application, the importance of deploying adjustable lossy to lossless compression techniques is emphasized in order to achieve acceptable performance via various kinds of communication networks...

| This paper presents a lossless block-transform coder based on the Hadamard transform that achieves a compression ratio as good as that of the current lossless JPEG-standard and about 10 to 20% lower than the currently best state-of-the-art technique Calic. The main advantage of the proposed technique is that it produces an embedded data stream which may be truncated to achieve lossy compressi...

With advances in multimedia technologies, demand for transmission and storage of voluminous multimedia data has dramatically increased and, as a consequence, data compression is now essential in reducing the amount of data prior storage or transmission. Compression techniques aim to minimise the number of bits required to represent image data while maintaining an acceptable visual quality. Imag...