As speed of communication data path is drastically improved in this decade due to the high data rate, evolutional technology is demanded to address the fast communication implementation. In this paper, we focus on data compression technology to speed up the communication data path. We have proposed a stream-based data compression called ASE coding. It compresses data stream based on the instantaneous data entropy without buffering and stalling for the compression processes. It is also suitable for hardware implementation. However, the stream-based data compression works heuristically with sensitive parameters that affect to the data compression ratio. If the parameters are statically configured, it does not follow the dynamic data entropy, and thus, the data compression performance becomes unstable. In this paper, we will disseminate the parameters, discuss the behaviors of those parameters and propose its autonomous adjustment methods. We will also propose adjustment algorithms for those parameters that follow the data entropy of the input data stream autonomously. Through experimental evaluations applying the algorithms, we will confirm the parameters are adjusted with depending on the data entropy in the data stream. And then, the compression ratio becomes stable as the compressor exploits the minimal entropy adaptively.

It is getting popular to implement an environment where communications are performed remotely among IoT edge devices, such as sensory devices and the cloud servers due to applying, for example, artificial intelligence algorithms to the system. In such situations that handle big data, lossless data compression is one of the solutions to reduce the big data. In particular, the stream-based data compression technology is focused on such systems to compress infinitely continuous data stream with very small delay. However, during the continuous data compression process, it is not able to insert an exception code among the compressed data without any additional mechanisms, such as data framing and the packeting technique, as used in networking technologies. The exception code indicates configurations for the compressor/decompressor and/or its peripheral logics. Then, it is used in real time for the configuration of parameters against those components. To implement the exception code, data compression algorithm must include a mechanism to distinguish original data before compression and the exception code clearly. However, the conventional algorithms do not include such mechanism. This paper proposes novel methods to implement the exception code in data compression that uses look-up table, called the exception symbol. Additionally, we describe implementation details of the method by applying it to algorithms of stream-based data compression. Because some of the proposed mechanisms need to reserve entries in the table, we also discuss the effect against data compression performance according to experimental evaluations.