Improved Block Based Segmentation for Jpeg Compressed Document Images
نویسندگان
چکیده
Image Compression is to minimize the size in bytes of a graphics file without degrading the quality of the image to an unacceptable level. The compound image compression normally based on three classification methods that is object based, layer based and block based. This paper presents a block-based segmentation. for visually lossless compression of scanned documents that contain not only photographic images but also text and graphic images. In low bit rate applications they suffer with undesirable compression artifacts, especially for document images. Existing methods can reduce these artifacts by using post processing methods without changing the encoding process. Some of these post processing methods requires classification of the encoded blocks into different categories. KeywordsAC energy, Discrete Cosine Transform (DCT), JPEG, K-means clustering, Threshold value --------------------------------------------------------------------***----------------------------------------------------------------------
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