APECE-505Intelligent System Engineering

Basics of Digital Image Processing!

Md. Atiqur Rahman Ahad

Reference books:

– Digital Image Processing, Gonzalez & Woods.

- Digital Image Processing, M. Joshi

- Computer Vision – a modern approach, Forsyth & Ponce

Topics

- Imaging types- Applications- Illusions

Image: - gazou 画像2-D function – f(x,y) x,y → spatial (plane) coordinatesf → intensity/ gray level of the image at that point (x,y)

Pixel: - gasou 画層Picture element, image element, pels, pixels

Image: 2D array of gray level or color values

Pixel: Array element Picture Element

• It’s 2D• It’s a square• It has one color• It may be any color

Pixel value: Arithmetic value of gray level or color intensity

Gray level image: f = f(x,y) Color image: f = {Rred(x,y), Ggreen(x,y), Bblue(x,y)}

Image Types:1. Gamma-ray imaging 2. X-ray imaging - rentogen3. Imaging in Ultraviolet (UV) bands4. Imaging in Visible and Infrared (IR) bands5. In Microwave band6. In Radio band~ others ...

Principal energy source for images: electromagnetic energy spectrum

1. Gamma-ray imaging- in nuclear medicine,

astronomical observations

Positron-emission tomography - PET

PET imageBone scan

Liver metastases of a colorectal tumor are clearly visible within the abdominal region of the image

PET scan of human brain

Bone scan

2. CT X-ray imaging

CAT – Computerized Axial Tomography

Head CT

Chest X-ray

3. UV band

Applications:LithographyIndustrial inspectionLaserMicroscopyBiological imaging

Normal vs. diseased corn

4. Visible & IR band

MicroscopyRemote sensing/ GIS

Remote sensing

GIS: 地理情報システム (Geographic Information System)

Infra-red (IR) [sekigaisen] imaging

USA

IR imaging

日本Bangladesh

Color thermal image

Automated visual inspections

Lens for eye - damages!!

Circuit board

Visual Spec. – applications

Finger print

License plate reading

5. Microwave – Radar

6. Radio band – medicine and astronomy

MRI – magnetic resonance imaging

knee spine

Neutron star

７ .Ultrasound imaging!

millions of pulses & echoes are sent, and received each second

akachan

thyroids muscle with lesion

Electron microscopy

TEM – Transmission electron microscopeSEM – Scanning electron microscope

Simultaneous contrast!

Optical illusions!

No line in the square!

circle!?

=?

Same distance? Parallel??