JPEG recapture image tamper detection method based on block effect grid offset

Abstract

Recaptured images are captured original or distorted image shown on the intermediaries,a high-quality recapture image is difficult to distinguish the authenticity of the human eye.Aimed at the tampering operation of JPEG image,a method of detecting block effect grid offset due to re-compression was proposed.The original image was compressed multiple times did not produce the block effect of the grid offset,and the recapture image,because of the recapture process would introduce background information that was not related to the original image,the re-compression of the block effect grid with the original grid is mismatched,and the average information loss amount of the image was used to detect whether the block effect grid generates an offset or not to detect the recapture image.Experiments show that this method is more accurate than the existing recapture image detection method,and the average detection time is shorter.

Keywords

• image forensics
• recapture images
• jpeg images
• repetitive compression
• offset of bag