Maximum Likelihood Estimation of JPEG Quantization Table in the Identification of Bitmap Compression History
نویسندگان
چکیده
To process previously JPEG coded images the knowledge of the quantization table used in compression is sometimes required. This happens for example in JPEG artifact removal and in JPEG re-compression. However, the quantization table might not be known due to various reasons. In this paper, a method is presented for the maximum likelihood estimation (MLE) of the JPEG quantization tables. An efficient method is also provided to identify if an image has been previously JPEG compressed.
منابع مشابه
Identification of bitmap compression history: JPEG detection and quantizer estimation
Sometimes image processing units inherit images in raster bitmap format only, so that processing is to be carried without knowledge of past operations that may compromise image quality (e.g., compression). To carry further processing, it is useful to not only know whether the image has been previously JPEG compressed, but to learn what quantization table was used. This is the case, for example,...
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