A hybrid LBG/lattice vector quantizer for high quality image coding

It is well known that a vector quantizer is an efficient coder offering a good trade-off between quantization distortion and bit rate. The performance of a vector quantizer asymptotically approaches the optimum bound with increasing dimensionality. A vector quantized image suffers from the following types of degradations: (1) edge regions in the coded image contain staircase effects, (2) quasi-constant or slowly varying regions suffer from contouring effects, and (3) textured regions lose details and suffer from granular noise. All three of these degradations are due to the finite size of the code book, the distortion measures used in the design, and due to the finite training procedure involved in the construction of the code book. In this paper, we present an adaptive technique which attempts to ameliorate the edge distortion and contouring effects

A Classification and Survey of Computer System Performance Evaluation Techniques

Classification and survey of computer system performance evaluation technique

Mass mortality of triggerfish Odonus niger (Rupell) along Dhanuskodi coast

On 3rd and 4th October 2007, several fishes of the species Odonus niger (locally known as Karuppu Klaathi ) were washed ashore along the coast for a stretch of nearly 4 km from Dhanuskodi check post to Arichumunai. On an average, 60 fishes were found lying in every 15 m of the stretch

Stranding of a whale shark, Rhincodon typus (Smith) at Pamban, Gulf of Mannar

The stranding of whale sharks in shallow waters along the Indian coast is not uncommon. Whale shark is listed as an endangered species as per the IUCN Red List (2000)

First record of rare skate off Gulf of Mannar

On 20th July 2007, one single specimen of roundel skate was accidentally caught by fish trawl net operated off Gulf of Mannar at a depth of 70m and landed at Pamban-Therkuvadi. The specimen was identified as Raja texana, Chandler, 1921, belonging to the family Rajidae. The fish was a female measuring 360mm in length and weighing 760 g. It is for the first time this species was recorded from the Gulf of Mannar Sea

Ecology and biodiversity of open sea cage farm at Mandapam, India

Farming of marine fin and shellfish species is an age old practice across the globe to augment the seafood demand and to supplement the rich protein food. Fin fish mariculture in India has been a recent initiative and the Central Marine Fisheries Research Institute was successful in developing captive breeding and seed production technique for cobia (Rachycentron canadum) and silver pompano (Trachinotus blochii). The open sea cages are particularly advantageous for maintaining the brood stock of potential species for captive breeding. However, the ecology of the cage farming sites is of paramount importance and should be conducive for the survival, health and growth of fishes that are farmed. In the present study, an attempt was made to understand the ecology and biodiversity of the cage farming area at Mandapam in Gulf of Mannar, south-east coast of India