Discrete wavelet transform(DWT)algorithm is an encryption algorithm based on wavelet transform for frequency decomposition of signals or images on multiple scales.Based on the Loongson 2K processor platform,the audio,...Discrete wavelet transform(DWT)algorithm is an encryption algorithm based on wavelet transform for frequency decomposition of signals or images on multiple scales.Based on the Loongson 2K processor platform,the audio,picture and video information as carriers to encrypt and decrypt the watermark information is realized by integrating and stacking the watermark detection functions on the processor platform of the switching nodes in the off-chain communication network within blockchain systems,using the sliding window mechanism of Loongson 2K to control the smoothness of the digital information,and by multi-thread mechanism of the processor to control the real-time performance of the digital signal transmission.The performance of the least significant bit(LSB)algorithm,discrete cosine transform(DCT)algorithm,and DWT algorithm is analyzed.The performance comparison of LSB algorithm,DCT algorithm,and DWT algorithm under filtering attack,scaling attack,noise attack,cropping attack,and spin attack is simulated respectively.The experimental results show that,filtered attack normalized correlation(NC)coefficient for DWT is 0.95786,for scaled attack is 0.98962,for noise attack is 0.93842,spin attack NC is 0.86823,and clipped attack NC is 0.878814.The DWT algorithm has the small image distortion rate,is more robust to audio and video watermarking against attack effects,and the experimental data are superior to the LSB and DCT algorithms.Using Loongson 2K multi-threading mode to control the real-time data transmission,greatly improves the practicability of DWT algorithm on embedded devices,which can be effectively applied to authenticity verification when media data such as images and audio are uploaded to the blockchain.展开更多
基金National Key Research and Development Program of China(2022YFB2702800)National Natural Science Foundation of China(72334003)+1 种基金Shandong Key Research and Development Program(2020ZLYS09)Jinan Program(2021GXRC084-2)。
文摘Discrete wavelet transform(DWT)algorithm is an encryption algorithm based on wavelet transform for frequency decomposition of signals or images on multiple scales.Based on the Loongson 2K processor platform,the audio,picture and video information as carriers to encrypt and decrypt the watermark information is realized by integrating and stacking the watermark detection functions on the processor platform of the switching nodes in the off-chain communication network within blockchain systems,using the sliding window mechanism of Loongson 2K to control the smoothness of the digital information,and by multi-thread mechanism of the processor to control the real-time performance of the digital signal transmission.The performance of the least significant bit(LSB)algorithm,discrete cosine transform(DCT)algorithm,and DWT algorithm is analyzed.The performance comparison of LSB algorithm,DCT algorithm,and DWT algorithm under filtering attack,scaling attack,noise attack,cropping attack,and spin attack is simulated respectively.The experimental results show that,filtered attack normalized correlation(NC)coefficient for DWT is 0.95786,for scaled attack is 0.98962,for noise attack is 0.93842,spin attack NC is 0.86823,and clipped attack NC is 0.878814.The DWT algorithm has the small image distortion rate,is more robust to audio and video watermarking against attack effects,and the experimental data are superior to the LSB and DCT algorithms.Using Loongson 2K multi-threading mode to control the real-time data transmission,greatly improves the practicability of DWT algorithm on embedded devices,which can be effectively applied to authenticity verification when media data such as images and audio are uploaded to the blockchain.
