信息与物理工程学院中南大学认识自己难，难于上青天医学图像处理医学图像处理Medical Image ProcessingMedical Image ProcessingTextbook: 1. Digital image processing (second edition, written by R.C.Gonzalez) 2. 医学图像处理与分析，罗述谦等著，科学出版社，2003UnRegistered信息与物理工程学院中南大学认识自己难，难于上青天Chapter1 IntroductionOne picture is worth more than ten thousand words Anonymous.UnRegisteredSchool of Info-Physics and Geomatics Engineering, CSU32009-3-16Several objectives about this chapter. define the scope of the field that we call image processing; Give a historical perspective of the origins of this field; Give an idea of the state of the art in image processing by examining some of the principal areas in which it is applied; Discuss briefly the principal approaches used in digital image processing; Give an overview of the components contained in a typical, general-goal image processing system; Provide direction to the books and other literature where image processing work normally is reported.UnRegisteredSchool of Info-Physics and Geomatics Engineering, CSU42009-3-161.1 What is digital image processing (DIP)1. Some relevant definitions of an image: An image may be defined as a two-dimensional function, f(x,y), where x and y are spatial coordinates, and the amplitude of f at any point is called the intensity or gray level of the image at that point. When x, y and f are all finite, discrete quantities, we call the image a digital image. A digital image is composed of a finite number of elements, each of which is referred to as a picture element, image element, pel, and pixel. Vision of the human is limited to the visual band of electromagnetic (EM) spectrum, but imaging machines can operate on all images generated by sources that include the entire EM spectrum, ultra-sound, electron microscopy and computer-generated images. 2. The difference between DIP and computer vision The ultimate goal is to use computers to emulate human vision, including learning and being able to make inferences and take actions base on visual inputs, and itself is a branch of artificial intelligence (AI).UnRegisteredSchool of Info-Physics and Geomatics Engineering, CSU52009-3-163. Three levels of DIP Usually, DIP is considered three types of computerized processes, but there are no clear-cut boundaries in them. a. Low-level processesinvolve primitive operations such as preprocessing to reduce noises, contrast enhancement, and image sharpening etc. One such process is characterized by the fact that both its inputs and outputs are images. b. Mid-level processing involves tasks such as segmentation, description of those objects and classification (recognition) of individual objects. Its characterization is that its inputs generally are images, but its outputs are attributes extracted from those images (e.g., edges, contours and the identity of individual objects). c. High-level processing involves “make sensing” or “comprehension” of an ensemble of recognized objects, as in image analysis, performing the cognitive functions normally associated with vision.Refer to example at the bottom of page 2.UnRegisteredSchool of Info-Physics and Geomatics Engineering, CSU62009-3-16UnRegisteredSchool of Info-Physics and Geomatics Engineering, CSU72009-3-16UnRegisteredSchool of Info-Physics and Geomatics Engineering, CSU82009-3-16UnRegisteredSchool of Info-Physics and Geomatics Engineering, CSU92009-3-16UnRegisteredSchool of Info-Physics and Geomatics Engineering, CSU102009-3-16UnRegisteredSchool of Info-Physics and Geomatics Engineering, CSU112009-3-161.2 A historical perspective of the origins about DIPPlease see textbook at page3-7 Keynote: 1) Three key supporting techniques: date storage, display, and transmission; 2) a series of key advances of computer; 3) Space program started from the early 1960s; 4) Application in Medical Imaging: CAT or CT (God N.Hounsfield, Allan M.Cormack), began in the late 1960s and early 1970s. 5) Other application, such as industry, medicine, biological science, etc.UnRegisteredSchool of Info-Physics and Geomatics Engineering, CSU122009-3-161.3 Examples offields that use DIPThe areas of application of digital image processing are so varied that it is difficult to include all context about this field. One of the simplest way to develop a basic understanding of the extent of image processing applications is to categorize image according to their source. Several forms of sources of energy are: 1) Electromagnetic (EM) energy spectrum; 2) Acoustic and ultrasonic imaging; 3) Electronic microscopy imging; 4) Synthetic images.UnRegisteredSchool of Info-Physics and Geomatics Engineering, CSU132009-3-161.3.1 imaging in the EM energy spectrumUnRegisteredSchool of Info-Physics and Geomatics Engineering, CSU142009-3-16 Examples of gamma-ray imaging. left: human bone scan; right: PET of a brain tumor and a lung tumorImage courtesy of G.E medical systemDr.Micheal, E.Casey, CTI PET systemUnRegisteredSchool of Info-Physics and Geomatics Engineering,