Research and Development (1999-2004)

Color Image Processing 

Low level processing of color images such as enhancement, segmentation, etc . In enhancing the color images, retinex computation model has been used. The method has been extended for video processing. A color rendition technique using the saturation and desaturation of color images from the CIE chromaticity chart has been developed.

Color Demosaicing 

Several new algorithms have been developed for color demosaicing with different motivations. An algorithm for color interpolation requiring low buffering has been developed. In another approach color interpolations are perfromed in the YUV color space instead of the conventional RGB color space. MRF processing has been used also in improving the end results obtained from ordinary color-interpolation techniques.  

Fractal Image and Video compression 

In fractal image compression, work has been carried out for improving the compression speed and decoding speed. A randomised algorithm has been developed for improving the speed and a new fast linear time decoding algorithm has also been developed. The study of the convergence criterion of fractal decoder also led to the development of a novel concept of relative fractal coding. The concept has been used for encoding color images, videos and multi-spectral satellite images.  

Image Resizing Techniques 

Image resizing techniques in the DCT domain were developed. Initially, an image halving and an image doubling alogorithms were proposed using sub-band DCT computation. Later, these approaches were generalised for arbitrary resizing of images in the DCT domain using block DCT composition and decomposition properties.  

Telemedicine system 

A telemedicine system had been developed, which has been operational in the School of Tropical Medicine, Kolkata since the year 2001 and was initially connected with two remote centers at Kuchbihar and Habra, North 24 Parganas respectively. The system integration and deployment was done by WEBEL, West Bengal. The system could run even in a low bandwidth channel (less than 5 Kbps data rate). Several field trials had been conducted between two distant places and demonstrations have been arranged in different hospitals such as, Vellore Christian Medical College, Westbank Hospital (connected with IIT BC Roy hospital) etc. The system has been appreciated by doctors and experts in general. Later the communication links were upgraded to 128 Kbps ISDN and 512 Kbps leased line. The network was also extended to include five more district hospitals (Burdwan, Baharampur, Siuri, Medinipur and Purulia) and NRS Medical College and Hospital, Kolkata. Different versions of the software (TelemediK) were released during this period.