Laser Speckle Contrast Analysis Using Adaptive Window

Abstract

This paper proposes a new image processing method for laser speckle, adaptive windowing laser speckle contrast analysis (aLASCA) that adaptively processes laser speckle images in the temporal and spatial direction. Conventional fixed window based LASCA has shortcoming in that it uses the same window size regardless of target areas. Inherently laser speckle contains undesired noise. Thus a large window is helpful for removing the noise but it results in low resolution of image. Otherwise a small window may detect small vascular but it has limits in noise removal. To overcome this trade-off, we newly introduce the concept of adaptive windowing to conventional laser speckle image analysis. We have compared conventional LASCA and its variants with the proposed method in terms of image quality and processing complexity.