The Art of Image Processing

The Art of Image Processing
Operators and Applications

Prof. Hong Man

Department of Electrical and Computer Engineering Stevens Institute of Technology

Outline
1. 2. 3. 4. 5. 6. 7. Introduction to Image Processing. g g Image Perception. Image Enhancement and Restoration. Image Interpolation and Visualization Image Analysis. Computed Tomography. Image and Video Compression.

1. Introduction
• Digital Image: a two dimensional array of pixels. g g y p – Size (or resolution) of an image: width: N pixels, height: M pixels. – Precision of pixels: 2n amplitude levels ⇒ n bits per pixel. – Overall data file size: N × M × n bits • Digital Video: a sequence of digital image frames. – Frame rate of a video sequence: f frames per second. – Overall data rate: N × M × n × f bits per second.

Image Example

LENA, 512 512 t LENA 512x512, true color (24 b/p), 786432 bytes. l b/ ) b t

Image Examples

Size: 2048x2560

Image Examples

Synthetic Aperture Radar

Infrared

Image Examples

Ultrasound

X-ray

Graphic Example

Video Example

AKIYO, 352x288 (CIF), 24 b/p, 30 f/s, 72.99 Mbits/s.

Animation Example

Image Processing
• Image Processing is to p g g perform numerical operations on p higher dimensional signals such as images and video sequences. • The objectives of image processing include: – Improving the appearance of the visual data image enhancement, image restoration – Extracting useful information image analysis, reconstruction from projection – Representing the image in an alternate and possibly more efficient form transformation, image compression

2. Image Perception

Brightness and Contrast

Spatial Frequency Response

Physical Model of Brightness Transition

Non-Linear Characteristics

3. Image Enhancement and Restoration
• Image enhancement and restoration refers to a general g g class of