Enhanced Block Truncation Coding Image using Digital Multi-tone Screen

Abstract— An improved version of Block Truncation Coding (BTC) termed Multitone Block Truncation Coding (MTBTC) is proposed. The presented framework exploits the digital multi toning strategy to obtain a superior quality BTC images. Previously, the halftone techniques such as ordered dithering, error diffusion and dot diffusion are extended to obtain different version of BTC. Though it performs good, there are still many scope for improvements. In recent times digital multitoning is gaining prominence and advanced multitone screens such as direct multibit search and clustered dot screens are developed. This multitone screen can enhance the visual quality significantly and offer more homogenous and noise free output for halftone images. Considering this properties, an upgradation to the halftone based BTC is proposed in this paper through the use of sophisticated multitone screens. From the simulation results, it is concluded that the proposed framework can provide very high quality output than any existing BTC techniques. Another highlighting aspect is that the proposed technique can facilitate higher block size processing and it is computationally very simple. In overall, the proposed scheme is an ideal candidate to implement compression for high resolution images and can be exploited further to adopt in artificial intelligent tasks.

Full Code at:

https://github.com/SankarSrin/MultitoneBTC.git

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