# An Image Authentication Scheme Using Merkle Tree Mechanisms
## 3 Proposed Method
### Image Verification

Table 2: The peak signal-to-noise ratio (PSNR) value on different image with different measurements. Figure 21: PSNR value comparison. ## 5 Conclusions

The slice block size \(N\) depends on each case, the smaller the size, the more accurate the detection, but the larger the generating of the Merkle tree will be, and vice versa. In this paper, we integrate Merkle tree technology, IPFS decentralized storage system, and an image verification process to achieve the goal of image verification. The proposed method shows the ability to perform integrity verification and recovery of images. From the simulation results, we have achieved a verification and restoration process of the image tampering area. We suggest that \(N=32\) and \(MSB=5\) is suitable in our proposed method. In terms of file types, we only mention the digital image in this paper. For future works, this may not only be applied to the digital image file but also expanded to video or any other multimedia (e.g., a decentralized document verification system). Through this system, governments or organizations can protect their documents, avoid tampering or falsifying messages, and ensure the credibility of documents. In addition to blockchain framework research, it is also worth studying for blockchain smart contracts. Conceptualization, [PERSON] and [PERSON]; methodology, [PERSON]; validation, [PERSON] and [PERSON]; formal analysis, [PERSON] and [PERSON]; investigation, [PERSON] and [PERSON]; resources, [PERSON]; data curation, [PERSON], [PERSON], and [PERSON]; writing--original draft preparation, [PERSON]; writing--review and editing, [PERSON] and [PERSON]; visualization, [PERSON] and [PERSON]. This research received no external funding. The authors declare no conflict of interest. ## References

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