An Efficient Static Filters for Sky Detection

Abstract

For colour based detection, the benefit of the static filter is the simplicity of the detection rules. Sky colour can be estimated in a precise cluster in any colour space if the conditions for the images remain constant (illumination controlled environment). A static sky filter clearly defines the boundaries that the sky has in a colour space. One or numerous varieties of threshold values for each colour space segments are shaped and the sky pixel values within these ranges for all the selected colour segments are defined as sky pixels. In this article, we have investigated and evaluate static sky filters for sky detection in complex scenarios. As a contribution, three new static sky filters for the RGB, nRGB and HSV colour spaces developed in this article. The highest performance (F-measure) depicted by the HSV colour space which is 0.56 while the lowest performance reported by the RGB colour space having an F-measure of 0.43. The three new static filters RGB, nRGB and HSV colour spaces are evaluated on the dataset (of 1000 complex images) by F-Measure elevation. Experimental results show that the viability of the developed static sky filters. It has also found that since the static filters use static boundaries, any shift of sky colour ranges from the defined boundaries affect the over-all performance.