# Daniel Suo

Scientific progress goes 'boink'

Ph.D. Candidate
Princeton University
Department of Computer Science

## Computer Vision

These notes are based on the course COS429, which is taught at Princeton by Professor Jianxiong Xiao.

## Notes that have not been organized

### Images

#### Pixels

From class notes: Conceptually, each pixel is a sample of the radiance arriving at a camera viewpoint from a direction. The camera records the number of photons captured for each pixel in its sensor in a given period of time and approximates the power (energy from the photons in a given time) for all pixels.

#### Photograph

From class notes: A photograph is a slice of the plenoptic function

• At a particular point of view $(x,y,z)$
• In the camera’s field of view (range over $\theta$ and $\phi$)
• At a certain time $t$
• Over a range of frequencies $\lambda$

### Image operations

#### Image transformations

• Image warping changes the domain of the image. In other words, we move pixels around (e.g., moving, scaling, rotating, fisheye).
• Image filtering changes the range of the image. In other words, we modify the pixels, but keep them in the same location (e.g., Instagram filters).

#### References

vision

3d-rotations

camera-matrix

color

homogenous-coordinates

homogenous-coordinates

index

large-small-aperture

lens-center-rays

lens-equation

lens-normal-rays

lens-trace-rays

lighting

ols

optics

pinhole-2d-geometry

pinhole-3d-geometry

pinhole-no-hole

pinhole-with-hole

pinhole-with-lens

projections

transformations

transformations