In this digital era, all the information takes the form of various media during communication. This leads to the need for more concern on the security measures so that the data being transmitted is resilient to various malicious attacks. In this paper, a modified line map algorithm is proposed and it is considered as a chaotic map to scramble the image. The resultant chaotic Line map has been employed to permute the image pixels, whereas diffusion is performed by XOR operation to completely encrypt the image. The robustness of the image against attacks has been increased by repeated permutation-diffusion round for ‘n’ number of times. Histogram analysis, Number of pixels change rate and correlation analysis has been performed to analyze the robustness of the proposed technique. Simulation results proves that this methodology can be implemented in real time applications. © 2020, Springer Nature Switzerland AG.