DIGITAL IMAGE PROCESSING

1. DIGITAL IMAGE PROCESSING

8. WHAT IS D.I.P. Processing of digital images by means of digital computers .

10. Digital Images World Camera Digitizer Digital Image Image Formation: (i) What determines where the image of a 3D point appears on the 2D image? (ii) What determines how bright that image point is? (iii) How is a digital image represented? (iv) Some simple operations on 2D images?

11. 0 10 10 15 50 70 80 0 0 100 120 125 130 130 0 35 100 150 150 80 50 0 15 70 100 10 20 20 0 15 70 0 0 0 15 5 15 50 120 110 130 110 5 10 20 50 50 20 250 PIXEL (picture element) Typically: 0 = black 255 = white Digital Images World Camera Digitizer Digital Image

14. Interest in DIP stems from two main applications • Human Interpretations Digital Television, (Optical band only) Video conferencing, Tele medicine, Internet movies, Facsimile. • Autonomous Machine perception  Industrial automation (Robotics), (Multi spectral band) Security & surveillance , Optical Character recognition, Biomedical imaging, Remote sensing, Geophysical & Seismic studies.

16. Types of images  Analog :Continuous spatial distributed and continuous amplitude optical intensing function f(x,y). Digital : Discrete spatial and discrete amplitude (gray level) optical intensity function f(m,n).

18. DIP APPLICATIONS Today, there is almost no area of technical endeavor that is not impacted in some way by DIP. Examples: i) Gamma ray imaging  Positron Emission Tomography (Nuclear imaging) (PET ) scans. Ex. Bone Scan, Nuclear reactor leakage, galactic explosion ii) X - Ray imaging  Bone scan, angiogram, Head CT scan, Star explosion, PCB flows, crack detection, Pipe line leakages. iii) UV band imaging  Lithography, industrial inspection, fluorescence microscopy, lasers, biological imaging, astronomical observations.

22. iv) Visible optical imaging Microscopy for industrial and bio imaging, micro inspection, remote sensing, office automation, law enforcement, bio-metric verification, object recognition, goods inspection, terrain classification, finger print recognition, PCB inspection, currency counting, number plate identification, lens deformation identification, pill inspection, packaging, baggage inspection at airports. v) IR imaging  Thematic and MSS, remote sensing, weather observation, Energy maps of world, Night vision. vi) Microwave imaging  Radar imaging, Mountain study, Military applications, target locations.

30. vii) Radio imaging Medicine Radio - MRI scan, Space imaging - pulsar study. viii) Acoustic imaging  Geological - seismic oil, mineral, exploration. Marine - Sea exploration, submarine Medical - Ultrasound imaging, in obstetrics to image baby, Thyroid study, muscle lesion study.

36. Image Parameters  i) Pixel Picture element p at spatial coordinate (x,y). ii) Brightness Scalar amplitude f of a pixel called gray (Intensity) value or gray level l iii) Color Vector amplitude of a pixel, actually denoted by Hue (H) and saturation ( S). iv) Spatial resolution Number of pixels in an image specified by horizontal (row) and vertical (column ) pixel. Rectangular image  M  N pixels Square image  N  N pixels

37. v) Gray level Resolution Number of intensities or gray levels (Intensity) (L) of a single pixel . L = 2l vi) Pixel depth Number of bits per pixel B & W image  1 bit / pixel Monochrome  8 bits / pixel Color  3 x 8 bit / pixel.