Indoor vs. outdoor scene classification in digital photographs

This paper proposes a new technique for the classification of indoor and outdoor images based on edge analysis. Our technique is based on analysing edge straightness in images. We make an original proposal that indoor images have a greater proportion of edges that are straight compared to outdoor images, and use multi-resolution estimates on edge straightness to improve our results. We also consider this method's possible applications in a real-time system. We compare our proposed technique with a number of other approaches that have been published on indoor/outdoor classification of images and convincingly show on a large database that our method generates much higher accuracy.