The Relationship of Image Processing to Mathematics

This blog is a follow-up of my previous blog: http://masterxinli.wordpress.com/2009/09/01/the-relationship-of-mathematics-to-image-processing/. I had sent out some cautious note about abuse of mathematics in image processing in that blog. The tone might sound a little bit overshoot; so I will “correct” myself  in this blog. As I have stated in the class, mathematics “turns art into science” – [...]

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Why should we care about reproducibility?

In the first week’s lectures, I have emphasized the difference between mentally reproducible and experimentally reproducible research (more or less: theory vs. experiment). Mathematical theories are mentally reproducible objects – you can understand them if you have the required background and think hard enough. From this perspective, mathematics is no different from art such as [...]

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Common Errors in MATLAB Computing

1. Forgot to convert to double. I mentioned that if you use ‘imread’ to read in an image, it will be in uint8 format. This format is less reliable than double because it does not “support” floating-point operation. It is a good idea to convert images to double format before any calculation of quantities such [...]

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What is Research-Based Learning?

How do we learn? Nobody knows for sure. We might know how we learn to play basketball (it takes a lot of practice) or how we learn to write computer programs (it takes a lot of thinking); but we don’t have a definite answer to an effective learning strategy for generic things including college education. [...]

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Blackboard-based Teaching vs. Powerpoint-based Teaching

I have been teaching EE465 for seven straight years. In the first few trials, I used totally blackboard-based teaching and closed-book exams. It is kind of easy to teach concepts related to binary images such as morphological filtering on blackboard because they are simply mathematical objects (e.g., set operations). But students did not like too [...]

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Good Engineering vs. Good Science

After today’s lecture on edge detection, I feel I need to tell you more about the difference between engineering and science. In particular, what is good engineering and good science? What is engineering? According to wiki, “Engineering is the discipline, art and profession of acquiring and applying technical, scientific, and mathematical knowledge to design and [...]

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On Frequency-Domain Visualization

Several of you were baffled by the “black image” while working on Part II of CA#6. “I can’t see anything!” “It is totally black.” “How do I observe?” Well, it is not just about keen eyesight – if you try hard enough, you can always spot something from that seemingly-black image. But there are a [...]

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Why is Fourier Transform Useful?

I hope most of you have followed me in today’s lecture to see the connection between continuous FT and discrete FT. The “hybrid” notation – discrete-time FT is really the bridge connecting the continuous and discrete worlds. I understand some topics I covered today, such as the duality between time-domain and frequency-domain, might not be [...]

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What Is More Important Than Your Grade

This is the second time I wrote a blog about this topic. In my previous attempt, I argued what you can learn from finishing a computer assignment is more important than the actual points you received. In this blog, I will lay out several other factors more important than your GPA especially from the perspective [...]

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A Note on Interpolation

You might be surprised by the fact that linear interpolation has been used for over 2000 years. Check the following wiki site out which contains the elementary material about linear interpolation http://en.wikipedia.org/wiki/Linear_interpolation I did not cover technical details of high-order interpolation which is based on the idea of fitting polynomials. This problem has also been [...]

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