PEE Processamento Digital de Imagens

Transcription

1 PEE Processamento Digital de ns Rangaraj Mandayam Rangayyan Roseli de Deus Lopes Copyright RMR / RDL PEE Processamento Digital de ns 1 Course Content Digital Fundamentals Transforms Enhancement Restoration Compression Segmentation Reconstruction from Projections * and Description Recognition and Interpretation Copyright RMR / RDL PEE Processamento Digital de ns 2 1

2 Recommended Text R. C. Gonzalez and R.E. Woods, Digital Processing, Reading, MA, 1992 (reprinted 1993). N. D. A. Mascarenhas and F. R. D. Velasco, Processamento Digital de ns, IV Escola de Computação, IME-USP, E. L. Hall, Computer Processing and Recognition, Academic Press, New York, A. Rosenfeld and A. C. Kak, Digital Picture Processing 2nd. Ed., v. 1 and 2, Academic Press, New York, K. R. Castleman, Digital Processing, Prentice-Hall, Englewood Cliffs, NJ, P. M. Embree and B. Kimble, C Language Algorithms for Digital Signal Processing, Prentice Hall, NJ, Copyright RMR / RDL PEE Processamento Digital de ns 3 Evaluation and Grading Exercices Project report Project involving the development of algorithms for Digital Processing, computer programming, and working on real images from any application area of your choice (such as medical imaging, remote sensing, robotics, and geophysical exploration). The algorithm need not be original. half page proposal (March 25th, 1999) report on a conference paper format seminar One written exam (1,5 hours at the last class) Copyright RMR / RDL PEE Processamento Digital de ns 4 2

3 It has been estimated that 75% of the information received by a human is VISUAL!!!! Computer Processing of Visual Information - the Digital Processing Revolution - was triggered by processing needs in developments such as lunar and other space missions, remote sensing, medical imaging, picture phone & digital television, and entertainment. Copyright RMR / RDL PEE Processamento Digital de ns 5????? Processing Computer Graphics Computer Vision Pattern Recognition Scientific Visualization Volume Visualization Visual Computing... Copyright RMR / RDL PEE Processamento Digital de ns 6 3

4 Processing Acquisition or Simulation Manipulation s and Attributes Analysis Geometric Display Copyright RMR / RDL PEE Processamento Digital de ns 7 Pattern Recognition Acquisition or Simulation Knowledge basis Manipulation s and Attributes Analysis Geometric Copyright RMR / RDL PEE Processamento Digital de ns 8 4

5 Computer Graphics Acquisition, Simulation or Modeling Manipulation s Synthesis Geometric Display Copyright RMR / RDL PEE Processamento Digital de ns 9 Volume Visualization Acquisition or Simulation Manipulation Volume Rendering Volumes and Attributes Analysis Synthesis Geometric Display Copyright RMR / RDL PEE Processamento Digital de ns 10 5

6 Visual Computing = IP + PR + CG + VV faster, bigger storage & cheaper computers engineering, medical imaging, geosciences, physics modeling, archeology Viabilty Applicabilty Acquisition or Simulation Knowledge basis Acquisition, Simulation or Modeling Manipulation Volume Rendering Discreet Data Analysis Synthesis Geometric Display Copyright RMR / RDL PEE Processamento Digital de ns 11 This course will concentrate on Digital Processing Acquisition or Simulation Manipulation s and Attributes Analysis Geometric Display Copyright RMR / RDL PEE Processamento Digital de ns 12 6

7 Digital Fundamentals Transforms Enhancement Restoration Compression Segmentation Reconstruction from Projections * and Description Recognition and Interpretation Copyright RMR / RDL PEE Processamento Digital de ns 13 Applications Medical Chromossome classification blood cell analysis chest radiograph analysis computed tomography digital radiography Remote Sensing land use & resource study detection of forest fires iceberg movements weather prediction Copyright RMR / RDL PEE Processamento Digital de ns 14 7

8 Applications Geology Oil & Mineral Exploration Seismic Imaging Oceanography Ocean bed analysis Plate Tectonics Astronomy Study of atmosfere Brightness Patterns of Stars Copyright RMR / RDL PEE Processamento Digital de ns 15 Applications Consumer Electronics Optical Character Recognition Picture Phone Automation Robot vision Inspection & control quality systems Entertainment Copyright RMR / RDL PEE Processamento Digital de ns 16 8

9 Examples Copyright RMR / RDL PEE Processamento Digital de ns 17 Examples Copyright RMR / RDL PEE Processamento Digital de ns 18 9

10 Digital Copyright RMR / RDL PEE Processamento Digital de ns 19 A Typical Digital Processing System Copyright RMR / RDL PEE Processamento Digital de ns 20 10

11 Considerations in Digitalization: Scanner Types Flying Spot - C.R.T, L.E.D. Spot illumination Flying Aperture - TV Cameras, Photodiode Arrays Object illumination Dynamic Range Dark Threshold to Saturation Threshold Signal Linearity A-D Conversion relationship may be modified to correct nonlinearities Copyright RMR / RDL PEE Processamento Digital de ns 21 Considerations in Digitalization: Geometric linearity May be verified by the use of grids and fiducial marks Spatial resolution May be expressed in terms of spacing of sampling grid, size of sampling spot, smallest object capable of being discriminated. Gray Scale Resolution depends on number of A-D conversion levels, dynamic range of sensor, mapping of A-D converter thresholds to range of signal Copyright RMR / RDL PEE Processamento Digital de ns 22 11

12 THE HUMAN VISUAL SYSTEM AND PERCEPTION Retina million rode: sensitive to very low levels of light intensity, provide scotopic vision. 5-7 million cones: color sensing, and acute or photopic vision. Retina adapts to ambient light levels. The HVS - bandpass system. This behavior is responsible for some visual illusions Copyright RMR / RDL PEE Processamento Digital de ns 23 12