1. DETECTION OF COPY MOVE FORGERY IN DIGITAL IMAGES

2. INTRODUCTION What is meant by Digital forgery? Examples for Digital forgery.

3. COPY MOVE FORGERY  It is a specific type of image manipulation, where a part of the image itself is copied and pasted into another part of the same image

4. DETECTION OF COPY MOVE FORGERY Requirements for the detection algorithm: Approximate match of small image segment It must work in a reasonable time

5. METHODS FOR DETECTION Exhaustive search Auto correlation

6. Input image Dividing into overlapping blocks Feature Extraction Lexicographically Sorting Locate the copy-move region DCT Number of blocks The detection result Approaches Computational time

7. EXHAUSTIVE SEARCH

8. AUTO CORRELATION Efficient method In this method the original & copied segments will introduce peaks in the auto correlation for the shifts that correspond to the copied moved segments.

9. STEPS FOR AUTO CORRELATION Apply Marr high pass filter to the tested image Compute auto correlation r of the filtered image Remove half of the auto correlation Find the max.of r, identify the shift vector, & examine the shift using the exhaustive method.

10. DETECTION BY  Block matching  Robust match

11. REFERENCES  J. Fridrich,“Methods for Tamper Detection in Digital Images”,proc.ACM  S.Saic, J.Flusser, B.Zitova and J. Lukas, “Methods for Detection of Additional Manipulations with Digital Images”