2results about How to "Large key space" patented technology

This invention proposes a chaotic speech encryption method based on a time-frequency dual-track system, belonging to the field of speech encryption technology. The method includes: preprocessing the original speech data to obtain a mono-channel filtered speech signal; extracting parameter features and calculating normalized speech energy as input to the chaotic system; generating a chaotic sequence and performing multi-step enhancement to obtain an enhanced key stream; generating a scrambling index after Fourier transforming the speech signal; scrambling and reshaping the real and imaginary components in the frequency domain and performing XOR diffusion; recombining the encrypted frequency domain matrix and inversely transforming it back to the time domain; and obtaining the final ciphertext through index permutation and fusion of speech feature parameters. This invention uses a frequency-domain dual-track scrambling-diffusion mechanism combined with an attractorless six-dimensional conservative hyperchaotic system to generate an enhanced key stream, thus avoiding speech distortion in time-domain encryption, triggering a global avalanche effect, and simultaneously improving the algorithm's resistance to various attacks, ensuring both the security of speech encryption and the fidelity of speech restoration.

This invention discloses a multi-image encryption method based on 3D face keys and multiplexed digital holography. The encryption steps include: using 3D face high-order data acquisition technology, chaotic face structured light phase mask generation technology, grating modulation technology, multiplexed digital holographic coding technology, and watermark embedding technology based on discrete wavelet domain singular value decomposition, multiple plaintext information images can be encrypted into an amplitude-type holographic ciphertext and embedded into a host image; the decryption steps include: the user must first calculate the face similarity using a 3D face multilayer perceptron neural network. If the similarity exceeds a preset threshold, authentication is successful. Then, the final decryption result is generated using watermark image extraction technology based on discrete wavelet transform, image decryption technology based on the Cramer-Kroni relation, and spectral filtering technology; otherwise, authentication fails. This method has advantages such as a large key space, high sensitivity, strong robustness of the 3D face key, and low decryption crosstalk.