A new version of region based BTC

An efficient description of image segments having an arbitrary shape is one of the main problems in object oriented coding. In our contribution, we introduce a scheme for region based coding derived from the BTC (block truncation code) algorithm (see Farkas, P. et al., "Adaptive Image Coding Based on Generalized IBTC", Broadband Islands 1994: Connecting with the End-User, Elsevier Science B.V., 1994). After segmentation, contours of the created regions are described by an 8-directional chain code as in MPEG-4. In the interior of the regions, there is applied a modified BTC algorithm that we call RTC-region truncation code. The results of compression are compared with BTC. Especially for low bit rate image coding, we achieved, in some cases, a better visual quality using similar values of an objective criterion parameter (MSE). In our approach, it is not necessary to follow the rules for the BTC channel encoder.