Image Processing Unit for General-Purpose Representation and Association System for Recognizing Low-Resolution Digits With Visual Information Variability

In this paper, a simple image processing unit (IPU) structure for a general-purpose representation and association machine system is proposed. We immediately apply our IPU to a digit recognition and hyper-acuity test. The quality of the digit images has been severely degraded to mimic visual information variability experienced in human visual systems. The degraded images are then fed to the IPU, which consists of a randomly constructed low-density parity check (LDPC) code, an iterative decoder, a switch, and scaling, and decision devices. The results show that: 1) our IPU can reliably recognize digits despite the image quality being poor; 2) our IPU provides a hyper-acuity capability comparable to human visual systems; and 3) our IPU with the randomly constructed LDPC code can provide significantly improved recognition capability compared with the IPU without coding, even though the code is not optimized for our tasks.