Abstract: There is a growing demand for techniques which improve the secure transmission of images of high confidentiality. The images captured by satellites and defense sensitive images handled by scientists need a strong protection when they are to be communicated for various applications. Image encryption algorithms need to be stronger in such cases. Various FPGA based image encryption algorithms have been proposed in the past to tighten the information security. This study analyses the hardware consumption issues of various 128x128 grayscale images which were encrypted with cellular automata circuits on Cyclone II EP2C35F672C6 FPGA. It was observed that the Logic Elements (LE) consumption varied for different test images considered in this encryption approach. This study analyses the performance of the image encryption algorithm on 15 different grayscale images based on technology schematic net lists, LE consumption, error metrics, Fast Fourier transform and histogram.