Contrast Enhancement of Colour Images using Transform Based Gamma Correction and Histogram Equalization
2017 (English)Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE credits
Student thesis
Abstract [en]
Contrast is an important factor in any subjective evaluation of image quality. It is the difference in visual properties that makes an object distinguishable from other objects and background.
Contrast Enhancement method is mainly used to enhance the contrast in the image by using its Histogram. Histogram is a distribution of numerical data in an image using graphical representation. Histogram Equalization is widely used in image processing to adjust the contrast in the image using histograms. Whereas Gamma Correction is often used to adjust luminance in an image.
By combining Histogram Equalization and Gamma Correction we proposed a hybrid method, that is used to modify the histograms and enhance contrast of an image in a digital method. Our proposed method deals with the variants of histogram equalization and transformed based gamma correction. Our method is an automatically transformation technique that improves the contrast of dimmed images via the gamma correction and probability distribution of luminance pixels. The proposed method is converted into an android application.
We succeeded in enhancing the contrast of an image by using our method and we have tested for different alpha values. Graphs of the gamma for different alpha values are plotted.
Place, publisher, year, edition, pages
2017. , p. 63
Keywords [en]
Contrast Enhancement, Image Processing, Traditional Histogram Equalization, Transformed Based Gamma Correction.
National Category
Signal Processing
Identifiers
URN: urn:nbn:se:bth-14424OAI: oai:DiVA.org:bth-14424DiVA, id: diva2:1111001
Subject / course
ET2566 Master's Thesis (120 credits) in Electrical Engineering with emphasis on Signal processing
Educational program
ETASX Master of Science Programme in Electrical Engineering with emphasis on Signal Processing
Presentation
2016-10-28, J3506, Blekinge Tekniska Högskola, Karlskrona, 09:00 (English)
Supervisors
Examiners
2017-06-192017-06-162017-06-19Bibliographically approved