Image and Video Bending

Last lab session, we were tasked to perform point transformation onto images - where one uses a transformation function \(\mathrm{T}[\ ]\) on an image \(f(x,y)\) to obtain another image \(g(x,y)\), or: \begin{equation}g(x,y)=\mathrm{T}\left[f(x,y)\right]\end{equation} [1]. Specifically, we were told to do the following transforms: image negative, logarithmic and gamma transform, contrast stretching and thresholding, and intensity-level slicing. From [1], we see that given that maximum gray value present in the image \(f(x,y)\) is \(L\), then for all gray level values in \(f(x,y)\) is \(r\), the resulting gray values for \(g(x,y)\) is \(s\), and the image's negative is obtained by: \begin{equation}s=L-r \label{nega}\end{equation} whereas for image's logarithmic transform is given by: \begin{equation}s=c\log(1+r) \label{log}\end{equation} and for gamma transform is: \begin{equation}s=cr^\gamma \label{gamma}\end{equation} To stretch the contrast of an image, we stretch c...

Last August 15, 2018, we had our first taste at image processing. While we didn't do anything hardcore, it was still fun to do since this was new to us, so the possibilities were endless. The first thing we were told to do was to create 30x30 images, either manually or through programming them. It wasn't really straightforward doing both since we were making .pgm images, a not-so-familiar image file-type that can be edited easily using Paint. A .pgm, or portable gray map image [1], is a very simple image file-type that encodes images using gray values on a scale from 0 to 255 where 0 represents black, and 255 white. Essentially, when encoding or editing .pgm files, all you need to do is to edit the gray scale values of each pixel in the image, and you get your result after saving it. How easy! In our case, we were tasked to create seven images, a dot, outline of a square, cross, filled circle, concentric squares of different gray values, and the first letter of my name whic...

This first semester of AY 2018-19, I am taking App Physics 186 which focuses (I think) on Image and Video Processing. Finally, a course that will help me understand how the popular freeware Tracker  works when I use it to analyze footage taken in our Physics 191/2 courses. As a start to this new blog, I'd like to test whether it is compatible with \(\LaTeX\), and so, I will be adding a few equations. Please don't mind them as it this only assures me that if it works, I know it is working. \begin{align}\label{euler} \mathrm{e}^{\mathrm{i}\,x}&=\sum_{n=0}^\infty\frac{(-1)^n}{(2n)!}x^{2n}+\mathrm{i}\,\sum_{n=0}^\infty\frac{(-1)^{n}}{(2n+1)!}x^{2n+1} \\ \label{fourier} \mathscr{F}\{g(\omega)\}&=\int_{-\infty}^{\infty}f(t)\mathrm{e}^{2\pi\mathrm{i}\,\omega t}\,\mathrm{d}t\end{align} Here, \eqref{euler} refers to the summation form of Euler's Formula, while \(\eqref{fourier}\) refers to a simple Fourier Transform. Another nice equation to note is that to get the \(n...