Study On Lossless Compression Algorithm For BMP True Color Image

With the progress of science and technology,especially the development of digital multimedia technology,human urgently need to deal with all kinds of images.Image processing technologies have penetrated all aspects of our lives,from the landscaping of the photo to the illegal vehicle monitoring,from medical CT imaging images to satellite remote sensing image analysis.The high demand for image processing and a large number of images data to be processed make the image processing technology with the rapid development.Lossless image compression is a basic image compression processing technology,which makes more and more areas to achieve a variety of images without distortion compression possible.Image lossless compression has wide range of applications,such as preservation of medical images,artwork,spacecraft and other images.Lossless image compression is a process of deleting image redundancy and restoring the original image completely.BMP is a commonly used file format for image processing under the Windows environment.This standard introduces two gray-scale image compression methods,i.e.,BI_RLE4 and BI_RLE8.However,there is no clear provided any compression standard for the color images.Thus it limits the application of BMP color images in practice.In order to solve the problem of BMP color images excessive occupation of storage space.In this paper,we propose a novel lossless compression algorithm for the 24 bit true color images.Our proposed algorithm is pretreating the adjacent pixel values in an image firstly,then the correlation image will be reduced by using least square method to obtain the smallest difference between pixel color values and the lossless compression of this image is realized by the entropy coding technique.The analysis of the experimental results shows that the proposed method is simple and easy to improve the compression ratio of lossless compression compared with the common ZIP and PNG lossless compression methods.It can be used as a new and effective lossless compression method is applied to image compression.