Image progressive acquisition for hardware systems

As the resolution of digital images increases, accessing raw image data from memory has become a major consideration during the design of image/video processing systems. This is due to the fact that the bandwidth requirement and energy consumption of such image accessing process has increased. Inspired by the successful application of progressive image sampling techniques in many image processing tasks, this work proposes to apply similar concept within hardware systems to efficiently trade image quality for reduced memory bandwidth requirement and lower energy consumption. Based on this idea, a hardware system is proposed that is placed between the memory subsystem and the processing core of the design. The proposed system alters the conventional memory access pattern to progressively and adaptively access pixels from a target memory external to the system. The sampled pixels are used to reconstruct an approximation to the ground truth, which is stored in an internal image buffer for further processing. The system is prototyped on FPGA and its performance evaluation shows that a saving of up to 85% of memory accessing time and 33%/45% of image acquisition time/energy is achieved on the benchmark image “lena” while maintaining a PSNR of about 30 dB.