Home » Tutorials » Page 4


Free tutorial portal for image processing, software development, computer graphics, programming and more. Various articles in the field of technology and software engineering.


Skin Detection and Segmentation in RGB Images

The Skin Detection and Segmentation is a process of finding skin-colored image regions from video frames or still pictures. Typically  this is a pre-processing step in the digital image analysis to find significant regions such as body, hands, faces, etc.

How to implement Symmetric Nearest Neighbor with FivekoGFX API

Symmetric Nearest Neighbor Filter

The Symmetric Nearest Neighbor Filter (SNN) is a non-linear edge preserving image processing filter. It is a very effective noise reduction technique that removes noise while maintaining sharp image edges. This graphic filter produce results very close to these of Median and Kuwahara filters.

fivekogfx gradient non-maximum suppression-thumb

Gradient Non-Maximum Suppression

The gradient Non-maximum suppression also known as edge thinning is a process of extracting thin, one pixel wide object’s contours. This process follows edge detection as a post processing step. The non-maximum contour suppression is one of the main steps of the popular Canny edge detector.

Median Filter Example - FivekoGFX

Median Filter – edge preserving filter tutorial

The Median filter is a nonlinear noise reduction technique that is widely used in image processing. It is very effective in cases of salt and paper noise (impulsive noise) and speckle noise. However, in cases of high noise levels, its performance becomes compatible with Gaussian blur filtering.


Mean Filter: Box blur for fast noise reduction

The Mean filter is a linear low-pass blur photo filter where each pixel in the output image has average value of its neighboring pixels. The algorithm is also famous as Box blur and performs as convolution with average blur mask.