US 12,341,869 B2
Method for encrypting visually secure image
Qiang Zhang, Dalian (CN); Bin Wang, Dalian (CN); YuanDi Shi, Dalian (CN); and XiaoPeng Wei, Dalian (CN)
Assigned to DALIAN UNIVERSITY, Liaoning (CN)
Filed by DALIAN UNIVERSITY, Dalian (CN)
Filed on Oct. 30, 2023, as Appl. No. 18/497,059.
Application 18/497,059 is a continuation of application No. PCT/CN2023/117592, filed on Sep. 8, 2023.
Claims priority of application No. 202211168486.0 (CN), filed on Sep. 19, 2022.
Prior Publication US 2024/0137207 A1, Apr. 25, 2024
Int. Cl. H04L 9/06 (2006.01)
CPC H04L 9/0618 (2013.01) [H04L 9/0643 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A method for encrypting a visually secure image, comprising the steps of
generating parameters and initial values of a six-dimensional hyperchaotic system and a hybrid chaotic system according to plaintext image information;
generating a chaotic sequence by iteration of the six-dimensional hyperchaotic system, and constructing a random sequence using the generated chaotic sequence;
performing Tetrolet transformation on the plaintext image to generate a coefficient matrix and performing optimized matrix scrambling for the coefficient matrix;
regarding a scrambled coefficient matrix, calculating a quantity of samplings allocated to each block after the coefficient matrix is divided into blocks according to a block sampling strategy based on region energy;
generating the chaotic sequence by iteration of the hybrid chaotic system, conducting an initial measurement matrix using the generated chaotic sequence, and obtaining a final measurement matrix by optimizing and normalizing the initial measurement matrix;
according to the block compressed sensing theory, using the block measurement matrix to measure a corresponding block coefficient matrix, and obtaining the measurement value matrix;
quantizing the measurement value matrix to obtain a quantized measurement value matrix;
scrambling a quantized measurement value matrix at pixel level by scrambling method based on domino tile issue, and obtaining the measurement value matrix after a first scrambling;
scrambling the measurement value matrix at pixel level after the first scrambling by the scrambling method based on domino overturn issue, and obtaining the measurement value matrix after a second scrambling;
diffusing the measurement value matrix after the second scrambling using a diffusion method based on a four-grid puzzle to obtain a diffused measurement value matrix, and performing a reverse diffusion operation on the diffused measurement value matrix to obtain a secret image matrix;
embedding the secret image matrix into a carrier image using non-negative matrix decomposition to obtain a ciphertext image.