@ARTICLE{ iet:/content/journals/10.1049/iet-cvi.2017.0190, author = {Meriama Mahamdioua}, author = {Mohamed Benmohammed}, keywords = {SIFT parameter default values;SIFT-based facial recognition systems;gamma correction value automatic estimation;comparative image lighting quality estimation;illumination variation;robust facial recognition;SIFT matching method;uncontrolled lighting conditions;SIFT automatic adaptation;local feature extraction;image illumination variation;SIFT feature matching;scale invariant feature transform;}, ISSN = {1751-9632}, language = {English}, abstract = {The scale invariant feature transform (SIFT), which was proposed by David Lowe, is a powerful method that extracts and describes local features called keypoints from images. These keypoints are invariant to scale, translation, and rotation, and partially invariant to image illumination variation. Despite their robustness against these variations, strong lighting variation is a difficult challenge for SIFT-based facial recognition systems, where significant degradation of performance has been reported. To develop a robust system under these conditions, variation in lighting must be first eliminated. Additionally, SIFT parameter default values that remove unstable keypoints and inadequately matched keypoints are not well-suited to images with illumination variation. SIFT keypoints can also be incorrectly matched when using the original SIFT matching method. To overcome this issue, the authors propose propose a method for removing the illumination variation in images and correctly setting SIFT's main parameter values (contrast threshold, curvature threshold, and match threshold) to enhance SIFT feature extraction and matching. The proposed method is based on an estimation of comparative image lighting quality, which is evaluated through an automatic estimation of gamma correction value. Through facial recognition experiments, the authors find significant results that clearly illustrate the importance of the proposed robust recognition system.}, title = {Automatic adaptation of SIFT for robust facial recognition in uncontrolled lighting conditions}, journal = {IET Computer Vision}, issue = {5}, volume = {12}, year = {2018}, month = {August}, pages = {623-633(10)}, publisher ={Institution of Engineering and Technology}, copyright = {© The Institution of Engineering and Technology}, url = {https://digital-library.theiet.org/;jsessionid=65vuvh6uwzof.x-iet-live-01content/journals/10.1049/iet-cvi.2017.0190} }