http://www.stringology.org/cgi-bin/getfile.cgi?t=pdf&c=-&y=2014&n=19

New tabulation and sparse dynamic programming based techniques for sequence similarity problems

We propose a binary image encryption method in joint transform correlator (JTC) by aid of the run-length encoding (RLE) and Quick Response (QR) code, which enables lossless retrieval of the primary image. The binary image is encoded with RLE to obtain the highly compressed data, and then the compressed binary image is further scrambled using a chaos-based method. The compressed and scrambled binary image is then transformed into one QR code that will be finally encrypted in JTC. The proposed method successfully, for the first time to our best knowledge, encodes a binary image into a QR code with the identical size of it, and therefore may probe a new way for extending the application of QR code in optical security. Moreover, the preprocessing operations, including RLE, chaos scrambling and the QR code translation, append an additional security level on JTC. We present digital results that confirm our approach.

Binary image encryption in a joint transform correlator scheme by aid of run-length encoding and QR code

https://par.cse.nsysu.edu.tw/~cbyang/person/publish/j08run_lcs.pdf

A fast and simple algorithm for computing the longest common subsequence of run-length encoded strings

Hardness of comparing two run-length encoded strings

In this paper, we consider a commonly used compression scheme called run-length encoding (abbreviated rle ). We provide lower bounds for problems of approximately matching two rle strings. Specifically, we show that the wildcard matching and k -mismatches problems for rle strings are 3sum -hard. For two rle strings of m and n runs, such a result implies that it is very unlikely to devise an o (mn )-time algorithm for either problem. We then propose an O (mn + p logm )-time sweep-line algorithm for their combined problem, i.e. wildcard matching with mismatches, where p ≤ mn is the number of matched or mismatched runs. Furthermore, the problem of aligning two rle strings is also shown to be 3sum -hard.

J. J. Liu

Papers

Finding a longest common subsequence between a run-length-encoded string and an uncompressed string

Edit distance for a run-length-encoded string and an uncompressed string