introofImage.ppt

Introduction of image processing 1, Digital Image and Properties 2, Digital Image Preprocessing 3, Image Smoothing 4 PDE and Image Smoothing 5, Image Sharpening 6, Fourier Transformation 7,Image Coding 1,Totally 32 lessons, 12 practices lessons, 20 lectures lesson. 2, Reference: Digital Image Processing second Edition , Rafael C. Gonzalez Richard E. Woods. Publishing House of Electronics Industry. Application of digital image processing compressing watermarking 压缩攻击后提出的水印 Image fusion 1, What is image The continuous image can be modeled by a continuous function of two or three variables f f x, y 2D , f f x, y, z 3D The image function values f correspond to the brightness at image points. When an image is generated from a physical process, its values are proportional to energy radiated by a physical source e.g. electromagnetic waves . As a consequence, f x,y must be nonzero and energy finite, that is We call the intensity of a monochrome image at any coordinates the grey level gl of the images at that point, That is And we have Common practice is to shift this interval numerically to the interval Where gl 0 is considered black, and gl L-1 is considered white on the grey scale. All intermediate values are shades of grey varying from black to white. 2, what is digital image How to convert the continuous image continuous with respect to the x and y coordinates and also in amplitude to digital image We all know that the output of most sensors is a continuous voltage waveform whose amplitude and spatial behavior are related to the physical phenomenon being sensed. sampling quantization Digitizing the coordinate values is called sampling. Digitizing the amplitude values is called quantization. quantization. The number of quantization levels should be high enough to permit human perception of fine shading details in the image. Most digital image processing devices use quantization into k equal intervals. If b bits are used to express th