Analysis of non-aligned double JPEG artifacts for the localization of image forgeries

Author

Bianchi, T. ; Piva, A.

Author_Institution

Dept. of Electron. & Telecommun., Univ. of Florence, Firenze, Italy

fYear

2011

fDate

Nov. 29 2011-Dec. 2 2011

Firstpage

1

Lastpage

6

Abstract

In this paper, we present a forensic algorithm to discriminate between original and forged regions in JPEG images, under the hypothesis that the tampered image presents a non-aligned double JPEG compression (NA-JPEG). Unlike previous approaches, the proposed algorithm does not need to manually select a suspect region to test the presence or the absence of NA-JPEG artifacts. Based on a new statistical model, the probability for each 8 × 8 DCT block to be forged is automatically derived. Experimental results, considering different forensic scenarios, demonstrate the validity of the proposed approach.

Keywords

computer forensics; data compression; image coding; statistical analysis; 8 × 8 DCT block; JPEG images; NA-JPEG artifacts; forensic algorithm; forensic scenarios; forged regions; image forgeries localization; nonaligned double JPEG artifacts; nonaligned double JPEG compression; original regions; statistical model; tampered image; Discrete cosine transforms; Forensics; Forgery; Image coding; Q factor; Quantization; Transform coding;

fLanguage

English

Publisher

ieee

Conference_Titel

Information Forensics and Security (WIFS), 2011 IEEE International Workshop on

Conference_Location

Iguacu Falls

Print_ISBN

978-1-4577-1017-9

Electronic_ISBN

978-1-4577-1018-6

Type

conf

DOI

10.1109/WIFS.2011.6123159

Filename

6123159