摘要
图像压缩是图像信息传递的一个重要途径。在对图像压缩的同时,还必须保证恢复图像的质量。目前已出现多种压缩技术并且有相应的国际标准,离散余弦变换(DCT)是许多图像编码国际标准的核心。DCT作为一种有损压缩算法,压缩比较高,且压缩后的图像视觉效果明显,因而成为图像压缩的一项重要技术,被广泛应用在图像压缩领域,比如国际静态图像压缩标准和动态图像压缩标准中都采用了DCT变换。文中介绍了DCT的原理以及它在图像压缩方面的应用。比较了两种基于DCT的图像压缩编码方法,提出了一种改进的基于二维DCT的图像压缩算法。该算法通过改进DCT系数的选取方法来控制图像压缩数组的大小,提高了图像恢复质量。在MATLAB上的实验结果表明,该算法提高了压缩图像的峰值信噪比,且耗时相对较少。
Image compression is an important way of image information transfer. The quality of image must be ensured when it is compressed. Among kinds of compressing methods,Discrete Cosine Transform（ DCT） is the core of most international image compressing standards. As a lossy compression algorithm,DCT can achieve high compression ratio and good visual effect. So the method becomes an important technology of image compression and it has been widely used in the areas such as image compression,especially in the JPEG and the M PEG. The principle of DCT and its applications in image compression are introduced in this paper. Based on comparison of two kinds of image compression based on DCT,an improved image compression method based on DCT is proposed. By choosing coefficient of DCT to control the size of an array of image compression,the newmethod improves the quality of image restoration. The experiments of M ATLAB showthat the proposed algorithm improves the PSNR of compressed images and consumes relatively fewtime.
出处
《计算机技术与发展》
2016年第1期147-149,154,共4页
Computer Technology and Development
基金
国家自然科学基金资助项目(11471114
61179027)
