طراحي وساخت سيستم نمايش دهنده ي رگ هاي بدن روي پوست

چكيده انگليسي :

Design and Implementation of a System to Visualize Body Veins on Skin Jafar Shahsavari j shahsavari@ec iut ac ir Date of Submission 2012 03 14 Department of Electrical and Computer Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language FarsiSupervisor Behzad Nazari nazari@cc iut ac irAbstract Vessel injections are a group of injections which drug material is directly injected into the body veins Since superficial veins are not easily seen in some individuals these injections encounter many difficultiesand injections have to be done by try and error in these situations Because of that a new system is designedand implemented in this thesis to assist the physicians in these injections This system applies imageprocessing techniques to show hidden body veins directly on the body skin The main idea is to capture veinimages in near infrared band because veins are more apparent in this band Then the necessarytransformations and enhancements are applied to these images and finally the resulted images are projectedback on the captured area by a projector In this manner deep veins would be visible to human naked eyedirectly on the body skin The projected image should be aligned precisely with the real body veins So it isnecessary to calibrate the camera and the projector In a former system high precision micrometer screwadjusted mechanical stages were used to set the optimal camera projector positions and the transformationfunction between the captured image and projected image was estimated using a simple affine transform by four circular control points located on the rectangular vertices In this thesis such mechanical parts arenot used To achieve the needed alignment a complicated model is used to transform the captured imageinto the projected image This transformation is estimated using the following procedure A chessboardimage is projected on the target by the projector and an image is captured using the camera Thetransformation between these two images is estimated using a group of control points These control pointsare located on the vertices of the chessboard image and should be extracted automatically This is not atrivial task because of some bothersome factors hairs blotch noise low contrast and nonuniformillumination So at the first step these bothersome factors should be eliminated in the captured images andin the next step all corners should be extracted We used two robust methods to extract corners robustly The success rate of our method for corner detection is 100 After corner detection the transformationfunction between the camera and projector is estimated using the extracted corners Global nonplanar orlocal planar models are a better choice in this application because of the curvature of the body Differenttransformations are tested and the best is selected by considering both the accuracy and the run time Forthorder polynomial is shown to be the optimal model in this respect Unsharp Masking and contrast limitedadaptive histogram equalization are applied to enhance image quality Different high contrast color schemescan also be applied to these images for better visualization Finally the transformed and enhanced imagesare projected back on the desired area with the accuracy of 0 089 mm using a Pico projector The appliedPico projector is in the pocket dimensions and uses DLP technology to make images on the target area Keywords Vein contrast enhancer vein viewer vein finder camera projector calibration spatialtransformations contrast enhancement

شهسواري، جعفر

طراحي وساخت سيستم نمايش دهنده ي رگ هاي بدن روي پوست

vein contrast enhancer , رگ يابي , تزريقات وريدي , vein viewer