The Detection And Implementation On FPGA Of Forged Digital Images Based On Improved SIFT

Today, the digital image can be forged without leaving any obvious traces of tampering due to the rapid development of advanced digital products and image processing software. When the forged digital images appear as basis in court, academic or other important occasions, it will bring lots of bad effects on people ’s lives and society. Therefore, it is a very important significance thing of studying on forgery detection technology.The purpose of digital image forgery detection techniques is to validate the authenticity and integrity of digital images. The passive blind method can validate the authenticity and integrity of digital images only depending on the content itself without any pre-embeded information. Copy-move forgery is one of the most common forgery methods in which case, a part of an image is copied and pasted into another part of the same image with the purpose of forging some important thing in the image. This paper mainly studies the passive blind detection techniques of digital image copy-move forgery.This paper uses the improved SIFT by Haar wavelet to detect the digital image copy-move forgery, and tries to realize the simulation on MATLAB and FPGA implementation of the improved SIFT algorithm. The simulation on MATLAB verified the feasibility, effectiveness and robustness of the improved SIFT forgery detection algorithm. The FPGA implementation of the improved SIFT forgery detection algorithm is completed on ML605. First, use Win Driver to drive the ML605 and then control the image data to transmit from PC to FPGA through the controller of DMA based on PCIE interface in application layer of the program generated by Win Driver. Then, process the image data, and transmit the results data from FPGA to PC through DMA. Finally, observe the results on MATLAB. The FPGA implementation of the improved SIFT detection algorithm contains the Verilog HDL implementation of Gaussian filter, differential Gaussian filter, keypoint extraction, Haar filter, keypoint orientation, feature extraction, feature matching and so on. Experiment results show that the algorithm of digital image forgery detection based on improved SIFT has better detection efficiency and robustness while ensuring detection accuracy compared with the SIFT detection algorithm. At the same time, the FPGA implementation of improved SIFT detection algorithm can complete the detection on copy-move forgery successfully with some certain robustness on post-image processing.