Fig. 9From: Estimating Previous Quantization Factors on Multiple JPEG Compressed ImagesAccuracy of the proposed method on JPEG 4-compressed images employing all the combinations QF1,QF2,QF3∈{60,65,70,75,80,85,90,95,100} and QF4=90 considering QF3 as ground truth (a). Further analysis have been conducted with QF3∈{90,95,100} (low accuracy regions): (b) and (c) show the results employing QF2 and QF1 as ground truth respectivelyBack to article page