Canny Edge Detection - 1/6-17/20

       This is my first post in 2020 so I would like to take the time to say Happy New Year and Decade. Last decade our world has hosted a lot of notable events like Occupy Wall Street, Brexit, natural disasters, school shootings, and the impeachment of Trump. Like every other decade, the 2010s were a mix of happiness and devastation. I know for me, the decade was a rollercoaster as it occupied more than half the time I have been on this planet. In the span of those 10 years, I have moved from Massachusetts to California and sort of "assimilated" with the people here. Since then, I have made a couple groups of friends and am happy about where I stand. My favorite things to happen last decade were the technological innovations made like the Raspberry Pi and the first picture of a black hole. Enough lamenting the past, let us get back to what I studied these past weeks.
Image result for 2010 decade
Funny image

       I learned about the Canny Edge Detection, a multi-stage edge detection operator used to extract edges for image processing. The operator was developed by John F. Canny in 1986 and has since been improved by third-party individuals. The edge detector can be summarized in five steps:
  1. Apply Gaussian filter to smooth the image (removes noise)
  2. Find the intensity gradients of the image
  3. Apply non-maximum suppression to get rid of spurious response to edge detection
  4. Apply double threshold to determine potential edges
  5. Track edge by hysteresis
CED does well compared to other methods because it has:
  1. A low error rate
  2. Edge points accurately localize on the center of the edge
  3. Edges in the image marked once
  4. A reduced noise level
All of which is done in a simple manner.

Image result for canny edge detection

       On January 16th, we visited Caltech to hopefully meet up with our professor, Dr. Hassibi, or any of his graduate students. Unfortunately, there was some miscommunication between our high school and them and we went to the lab with no one there. There wasn't a good way for us to spend that time other than telling each other our research topic in-depth, essentially making our trip a show-and-tell event. While there, we met up with an assistant researcher in the Biology department who scribbled his thoughts and ideas on the whiteboard. The once clear wall now stands before us, carrying incomprehensible information about how DNA could be formed into modules that create electrical pulses. I did not catch his name but he was a fine person who spent the time to boil down an explanation for us. I wish to meet with him again because it looked like he was super passionate about his research. People with passion will stop at nothing to help explain something to others.

       I'd like to conclude this biweekly post with an interesting band I found. They go by the name of "Lucky Kilimanjaro". They are a band from Japan that produces Pop music. Although they have a relatively small audience, their fanbase is super supportive which is a good sign for upcoming musicians. Despite not knowing a whole lot of Japanese, I still find some joy out of their music and is why I wanted to talk about them. Below is my favorite song from them.


Until next time...
- Jeff Wang

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