Recent Projects
 |
What is the Space of Spectral Sensitivity Functions for Digital Color Cameras?Camera spectral sensitivity functions relate scene radiance with captured RGB triplets. They are important for many computer vision tasks that use color information, such as spectral imaging, color rendering, and color constancy. In this paper, we aim to explore the space of spectral sensitivity functions for digital color cameras. After collecting a database of 28 cameras covering a variety of types, we find this space convex and two-dimensional. Based on this statistical model, we propose two methods to recover camera spectral sensitivities using regular reflective color targets (e.g., color checker) from a single image with and without knowing the illumination. We show the proposed model is more accurate and robust for estimating camera spectral sensitivities than other basis functions. We also show two applications for the recovery of camera spectral sensitivities -- simulation of color rendering for cameras and computational color constancy. |
Previous Projects
 |
Master thesis: EMCCD Driver, Image Pre-processing & Acquisition Circuit DesignEMCCD (Electronic Multiplication CCD) is a new type of solid-state imaging sensor. Owing to the unique feature of on-chip multiplication. EMCCD obtains the same level of sensitivity compared with ICCD and EBCCD, Back Illuminated EMCCD-EMBCCD further enhanced the sensitivity. In addition, based on the standard CCD fabrication techniques, EMCCD also features high quantum efficiency. Due to these advantages, EMCCD has various applications on astronomy, aerospace, life science and military. This paper has implemented an imaging system circuit design based on EMBCCD. |
 |
Senior Project: CMOS Image transmission based on Cypress USB ControllerBecause of its low-cost, low-power assumption and flexibility, CMOS image sensor has been widely used in several applications including photography, machine vision etc. In this project, we design a digital video transmission system of CMOS image sensor based on USB interface. We use a Cypress EZ-USB FX2 CY68013 USB controller chip to interface with CMOS image sensor (Micron MT9V032). It efficiently controls the time sequences of the CMOS image sensor by using the GPIF interface and the feature of flow state, and achieves high-speed data transfer without using external FIFO and CPLD which are essential components in normal solutions. Through the integrated I2C interface on the 68013, we can conveniently configure the register stored in CMOS online to adjust parameters such as shutter, gain, gamma etc. |