A Novel Compression Technique for JPEG Error Analysis and for Digital Image Applications

Abstract

In computing, JPEG is a commonly used method of lossy compression for digital photography (image). The degree of compression can be adjusted, allowing a selectable tradeoff between storage size and image quality. JPEG compression is used in a number of image file formats. The compression method is usually lossy, meaning that some original image information is lost and cannot be restored .There is an optional lossless mode defined in the JPEG standard. There are so many previous methods were there for jpeg compressions which were not performing well on some errors like quantization, rounding and truncation errors. The proposed method deals about all these error minimizations by JPEG error analysis. JPEG is one of the most extensively used image formats. Understanding the inherent characteristics of JPEG may play a useful role in digital image. The main errors of JPEG include quantization, rounding, and truncation errors. Through theoretically analyzing the effects of these errors on single and double JPEG compression, we have developed three novel schemes for image including identifying whether a bitmap image has previously been JPEG compressed, estimating the quantization steps of a JPEG image, and detecting the quantization table of a JPEG image. When compared to existing techniques the proposed method outperforms for the images of small sizes. The proposed method can also reliably detect JPEG image blocks, which are as small as 8X8 pixels. The work is mainly used for digital image authentication. Extensive experimental results show that our new methods significantly outperform existing techniques especially for the images of small sizes.