Aiming at the problems of Byzantine Fault Tolerant （BFT） consensus mechanisms in the blockchain such as high communication complexity， complex view change and poor scalability， a consensus algorithm based on binomial swap forest and HotStuff named HSP （HotStuff Plus） consensus algorithm was proposed. In order to realize signature batch verification and signature aggregation， the Boneh-Lynn-Shacham （BLS） signature algorithm was adopted； in order to reduce the communication complexity of the system， threshold signature technology was adopted； in order to reduce the communication complexity during view change， the consensus process adopted a three-phase confirmation method； in order to reduce the number of communications between the primary and secondary nodes and reduce the pressure on the primary node when aggregating signatures， an improved binomial swap forest technology was adopted. Test results show that when the total number of system nodes is 64 and the request and reply are both 256 bytes， the throughput of HSP consensus algorithm is 33.8% higher than that of HotStuff consensus mechanism， and the consensus delay of HSP consensus algorithm is 16.4% lower than that of HotStuff consensus mechanism. It can be seen that HSP consensus algorithm has better performance when the number of nodes is large.

The existing watermarking algorithm based on image moments has the disadvantages of small capacity, large complexity and its robustness should be improved in further study. A new zero-watermarking against geometric attacks was proposed. Using the image normalization and the features of Tchebichef moments, the rotation normalized Tchebichef moments of original image was calculated in the unit circle, and the upper-left corner of Tchebichef moments was scanned into numerical matrix. Afterwards, binary secret key was generated according to numerical matrix and watermark image, and saved to zero-watermarking information database. In detection, the same process was executed to draw out numerical matrix from the unauthenticated image, and watermark image was extracted by using the secret key and numerical matrix. The experimental results show that this algorithm is robust against rotation attacks of random angles, scaling attacks and common signal processing operations, even combined attacks.