Okay, let’s calculate. Yiheng has a mix of programming skills, including C++, Python, and Objective C, which are in demand. He also has experience in computer vision and digital image processing, which are valuable skills. However, his limited English proficiency might affect his earning potential. Considering his skills and experience, I'd estimate his hourly rate to be around $125, which is slightly lower than average for a software developer in Seattle. This is because his language proficiency is limited, which might limit his job opportunities and salary potential. However, his technical skills are still valuable, especially in the computer vision and digital image processing spaces.