Fault-tolerant Quantum Circuits and Computation Architectures for Image Processing Applications
Israel Olabisi Koiku
Abstract
The classical computer is becoming inefficient to process the ever-increasing number of images generated on daily basis for various purposes. To address this, researchers have shifted attention to exploring the potential of quantum computing to realize image processing. As image pixels are represented as color intensities of integral points on the cartesian coordinates, there is need for interpolations of the color and positions of the pixels to restore the integral points locations after the image points have undergone some computational transformations. While color interpolation has received some attention in Quantum Image Processing, coordinate interpolation has not been explored. In this work, a novel quantum architecture that does image coordinate interpolation is proposed. Furthermore, the architecture generalizes the concept of nearest neighbor interpolation. By partitioning the distance between two adjacent pixels into 2𝑛 discrete levels, a computed point between them can be interpolated to either way depending on the difference between the computed point and a predetermined coefficient that determines where the user wishes to interpolate to. The proposed architecture is based on a quantum subtractor and a novel quantum conditional incrementor, which is another project that was completed in this study. Likewise, the proposed conditional incrementor is based on a novel circuit for incrementor which is also presented in this dissertation together with its associated decrementor. A novel construction of discrete time quantum walk (DTQW) along a closed ring was also proposed as another application of the proposed incrementor. DTQW has wide applications including "universal computation" and in image processing. Therefore, the contributions of this study include introduction of a coordinate interpolation circuit, design and construction of T-count optimized incrementor, decrementor, conditional incrementor, conditional decrementor, conditional incrementor/decrementor circuits, and a T-count efficient implementation of discrete-time quantum walk.