Duvenhage, B2016-08-192016-08-192015-11Duvenhage, B. 2015. Long range image enhancement. In: Image and Vision Computing, Auckland, New Zealand, 23-24 November 2015http://hdl.handle.net/10204/8704Image and Vision Computing, Auckland, New Zealand, 23-24 November 2015. Due to copyright restrictions, the attached PDF file only contains the abstract of the full text item. For access to the full text item, please consult the publisher's websiteTurbulent pockets of air in the atmosphere blur and disrupt the Point Spread Function (PSF) of a surveillance system. The PSF peak is offset in location, changed in size and in short exposures (or mild conditions) noticeably fragmented or speckled. These effects result in what is called heat shimmer or scintillation. The turbulence also causes the effective PSF convolution kernel to vary over time as well as across the image. When doing long range surveillance even mild turbulence can significantly degrade the surveillance system performance. This paper discusses an image processing method that tracks the behaviour of the PSF and then de-warps the image to reduce the disruptive effects of turbulence. Optical flow, an average image filter and a simple unsharp mask is employed to respectively track the centre of the PSF, de-speckle the image and regain the sharpness of the image. The algorithm is efficient enough to process 720p video at 10 frames per second on low power CPU-only platforms such as an Intel i5 NUC.enLong range surveillanceScintillationDe-warpPoint spread functionPSFConference PresentationDuvenhage, B. (2015). Long range image enhancement. http://hdl.handle.net/10204/8704Duvenhage, B. "Long range image enhancement." (2015): http://hdl.handle.net/10204/8704Duvenhage B, Long range image enhancement; 2015. http://hdl.handle.net/10204/8704 .TY - Conference Presentation AU - Duvenhage, B AB - Turbulent pockets of air in the atmosphere blur and disrupt the Point Spread Function (PSF) of a surveillance system. The PSF peak is offset in location, changed in size and in short exposures (or mild conditions) noticeably fragmented or speckled. These effects result in what is called heat shimmer or scintillation. The turbulence also causes the effective PSF convolution kernel to vary over time as well as across the image. When doing long range surveillance even mild turbulence can significantly degrade the surveillance system performance. This paper discusses an image processing method that tracks the behaviour of the PSF and then de-warps the image to reduce the disruptive effects of turbulence. Optical flow, an average image filter and a simple unsharp mask is employed to respectively track the centre of the PSF, de-speckle the image and regain the sharpness of the image. The algorithm is efficient enough to process 720p video at 10 frames per second on low power CPU-only platforms such as an Intel i5 NUC. DA - 2015-11 DB - ResearchSpace DP - CSIR KW - Long range surveillance KW - Scintillation KW - De-warp KW - Point spread function KW - PSF LK - https://researchspace.csir.co.za PY - 2015 T1 - Long range image enhancement TI - Long range image enhancement UR - http://hdl.handle.net/10204/8704 ER -