Xử lý ảnh trong cơ điện tử: Machine Vision. Chapter 2: Digital Image Fundamentals92

TRƯỜNG ĐẠI HỌC BÁCH KHOA XỬ LÝ ẢNH TRONG CƠ ĐIỆN Machine Vision Giảng viên: TS Nguyễn Thành Hùn Đơn vị: Bộ môn Cơ điện tử, Viện Cơ Hà Nội, 2021 Chapter Digital Image Fundam Image Sensing and Acquisition Image Sampling and Quantization Some Basic Relationships Between Pixels Basic Mathematical Tools Used in Digital Image P Image Sensing and Acquisi ❖Image Sensing and Acquisition (a) Single sensing element (b) Line sensor (c) Array sensor Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Image Sensing and Acquisi ❖Image Acquisition Using a Single Sensing Element Combining a single sensing element with mechanical motion to generate a 2Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Image Sensing and Acquisi ❖Image Acquisition Using Sensor Strips (a) Image acquisition using a linear sensor strip Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) (b) Image acquisition u a circular sensor strip Image Sensing and Acquisi ❖Image Acquisition Using Sensor Arrays An example of digital imag (energy) source (b) A scen Projection of the scene ont Digitized image Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Image Sensing and Acquisi ❖A Simple Image Formation Model ➢ We denote images by two-dimensional functions of the form f(x f(x, y) = i(x, y) r(x, y) • i(x, y): the amount of source illumination incident on the scene • r(x, y): the amount of illumination reflected by the objects in th Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Chapter Digital Image Fundam Image Sensing and Acquisition Image Sampling and Quantization Some Basic Relationships Between Pixels Basic Mathematical Tools Used in Digital Image P Image Sampling and Quantiz ❖Basic Concepts in Sampling and Quantization ➢ Digitizing the coordinate values is called sampling Digitizing t values is called quantization (a) Continuous image (b) A scan line showing intensity variations along line AB in the continuous image (c) Sampling and quantization (d) Digital scan line (The black border in (a) is included for clarity It is not part of the image) Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Image Sampling and Quantiz ❖Basic Concepts in Sampling and Quantization (a) Continuous image projected onto a sensor array (b) Result of image samplin and quantization Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Basic Mathematical Tools Used in Digital ❖Basic Set Operations Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Basic Mathematical Tools Used in Digital ❖Logical Operations Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Basic Mathematical Tools Used in Digital ❖Logical Operations Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Basic Mathematical Tools Used in Digital ❖Single-Pixel Operations (a) An 8-bit image (b) Intensity transformation function used to obtain the digital equiv negative of an 8-bit image The arrows show transformation of an arbitrary input intensi corresponding output value (c) Negative of (a), obtained using the transformation functi Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Basic Mathematical Tools Used in Digital ❖Neighborhood Operations Local averaging using neig procedure is illustrated in neighborhood (c) An aorti using Eq (2) with m = m 790 x 686 pixels Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Basic Mathematical Tools Used in Digital ❖Geometric Transformations Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Basic Mathematical Tools Used in Digital ❖Geometric Transformations Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Basic Mathematical Tools Used in Digital ❖Geometric Transformations Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Basic Mathematical Tools Used in Digital ❖Geometric Transformations (a) A 541 x Image rota interpolatio Image rota interpolatio bicubic int sections (e numbers sh Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Basic Mathematical Tools Used in Digital ❖Geometric Transformations (a) A digital image (b counterclockwise dire rotation) (c) Rotated area as the original im accommodate the ent Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Basic Mathematical Tools Used in Digital ❖Image Registration Image registration (a) Ref (geometrically distorted im points are shown as small corners (c) Registered (ou in the border) (d) Differen showing more registration Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Basic Mathematical Tools Used in Digital ❖Vector and Matrix Operations Forming a vector from corresponding pixel values in three RGB component Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Basic Mathematical Tools Used in Digital ❖Image Transforms ➢ 2-D linear transforms ➢ Inverse transform Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Basic Mathematical Tools Used in Digital ❖Image Transforms General approach for working in the linear transform dom Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) Basic Mathematical Tools Used in Digital ❖Image Transforms (a) Imag interferen transform caused b were enl Mask use (d) Resu modified Rafael C Gonzalez, Richard E Woods, “Digital image processing,” Pearson (2018) .. .Chapter Digital Image Fundam Image Sensing and Acquisition Image Sampling and Quantization Some Basic Relationships Between Pixels Basic Mathematical Tools Used in Digital Image P Image. .. Result of image samplin and quantization Rafael C Gonzalez, Richard E Woods, ? ?Digital image processing,” Pearson (2018) 2 Image Sampling and Quantiz ❖Representing Digital Images (a) Image plo Image. .. Woods, ? ?Digital image processing,” Pearson (2018) 2 Image Sampling and Quantiz ❖Representing Digital Images Rafael C Gonzalez, Richard E Woods, ? ?Digital image processing,” Pearson (2018) 2 Image