Nisarg Nigam

Spatial filters assign the value of a pixel based on their neighbors. Filters are defined as matrices, known as kernels, and are applied to an image through an operation known as a convolution.

The image being used for this post is a rgb2gray converted lena image. Each kernel is a 3x3 pixel image with numbers that determines how the image will be affected. In the example of horizontal and vertical sobel filters, the horizontal and vertical points are being focused on. In the example of the Gaussian blur, pixels in the center are focused on and corner pixels are blurred. This creates a bokeh effect.

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A dark image and its color intensity distribution

The previous post introduced the distribution plots of the channel values. Let us consider this dark image. The histogram of the channel values shows that most pixels have low intensity values. We want to make this distribution uniform, which is equivalent to making the CDF (blue) linear (red).

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Nisarg Nigam

Nisarg Nigam

MS Data Science student at Asian Institute of Management