Run-length encoding

About: Run-length encoding is a research topic. Over the lifetime, 504 publications have been published within this topic receiving 4441 citations. The topic is also known as: RLE.

Selection from plural run-length encoding methods to compress a data string

Abstract: A run-length encoding method is selected (502) from a plurality of such methods based on content of a bit string (such as a traffic indication map TIM in Smart Meter networks). Encoding parameters (such as codeword length) are also selected (504) based on the content, and the bit string is encoded (506) according to the selected method and parameters. In various non-limiting examples: different run-length encoding methods arc selected (508) based on whether the bit string has sequences of consecutive same-value bits interspersed with isolated. opposite-value bits or interspersed with sequences of consecutive opposite-value bits; the codeword length parameter is selected (510) based on how many consecutive same-value bits arc in the bit string; and encoding entails disposing a marker between code words to indicate that the codeword continues.

VaFLE: Value Flag Length Encoding for Images in a Multithreaded Environment

Abstract: The Run Length Encoding (RLE) algorithm substitutes long runs of identical symbols with the value of that symbol followed by the binary representation of the frequency of occurrences of that value. This lossless technique is effective for encoding images where many consecutive pixels have similar intensity values. One of the major problems of RLE for encoding runs of bits is that the encoded runs have their lengths represented as a fixed number of bits in order to simplify decoding. The number of bits assigned is equal to the number required to encode the maximum length run, which results in the addition of padding bits on runs whose lengths do not require as many bits for representation as the maximum length run. Due to this, the encoded output sometimes exceeds the size of the original input, especially for input data where in the runs can have a wide range of sizes. In this paper, we propose VaFLE, a general-purpose lossless data compression algorithm, where the number of bits allocated for representing the length of a given run is a function of the length of the run itself. The total size of an encoded run is independent of the maximum run length of the input data. In order to exploit the inherent data parallelism of RLE, VaFLE was also implemented in a multithreaded OpenMP environment. Our algorithm guarantees better compression rates of upto 3X more than standard RLE. The parallelized algorithm attains a speedup as high as 5X in grayscale and 4X in color images compared to the RLE approach.

A novel method for multi-modal fusion based image embedding and compression technique using CT/PET images

Abstract: Image embedding has a wide range of applications in the medical field. This method is helpful in securing the information of the patients from the intruders with high storage capacity. The medical images of different modalities like CT and PET along with Patient Medical Image (PMI) can be sent to the physicians across the world for the diagnosis. Due to the bandwidth and storage constraint, medical images must be compressed before transmission and storage. This paper presents an evaluation on fusion based image embedding and reconstruction process for CT and PET images. The comparison of image fusion technique is processed using Wavelet Transform (WT) and Complex Contourlet Transform (CCT) and the analysis of compression method is estimated by using Run Length Encoding (RLE) and Huffman Encoding (HE) respectively. The proposed method is helpful in securing the patient information and it provides high hiding capacity for storage in the hospital digital database with improved values of MSE and PSNR.

Run-length encoding and decoding of bitmap data

Abstract: PROBLEM TO BE SOLVED: To encode superimposed subtitling used for text information and graphics data on bitmaps. SOLUTION: If subtitle bit maps exceed a video frame, only portions are displayed at a time. The bitmaps are a separate layer lying above the video, e.g., for synchronized video subtitles, animations and navigation menus, and therefore contain many transparent pixels. An advanced adaptation for bitmap encoding for HDTV per frame is defined for the Blu-ray Disc Prerecorded format, and optimized compression effects are provided for such subtitling bitmaps, but this method is achieved by a four-stage run length encoding. Shorter or longer sequences of transparent pixels are encoded using the second or third shortest code words, single pixels of different color are encoded using the shortest code words, and shorter and longer sequences of pixels of equal color use the third or fourth shortest code words. COPYRIGHT: (C)2011,JPO&INPIT