IT 523 Digital Image Processing Prof Asim Banerjee

IT 523 Digital Image Processing Prof. Asim Banerjee asim_banerjee@daiict. ac. in IT 523 - Digital Image Processing

What is an Image? • Image is a two dimensional light-intensity function, f(x, y), where the value of f at a spatial location (x, y) is the intensity of the image at that point. NOTE: The function f(x, y) can be a measure of the reflected light (photography), X-ray attenuation (X-Rays) or any other physical parameter. IT 523 - Digital Image Processing 2

What is a Digital Image? • Digital Image is obtained by sampling and quantizing the function f(x, y). • Thus a digital image is discrete in time and quantized in amplitude. Question: - What are the issues that one has to take care of in converting an image to its digital form? IT 523 - Digital Image Processing 3

What is Digital Image Processing? • Digital Image Processing (DIP) involves processing the digital image (using the computer) to extract meaningful information from the images. NOTE: The meaningful information is dependent on the application. IT 523 - Digital Image Processing 4

Why is DIP Important? • Importance of Digital Image Processing stems from two principal application areas 1. Improvement of pictorial information for human interpretation 2. Processing of scene data for autonomous machine perception IT 523 - Digital Image Processing 5

1. Improvement … Human Interpretation • • • Involves selection of printing procedures and distribution of brightness levels Improvements on processing methods for transmitted digital pictures Application areas include – – – – Archeology Astronomy Biology Industrial Applications Law enforcements Medical Imaging Space program etc. IT 523 - Digital Image Processing 6

2. Processing…Machine Perception • • Focuses on procedures for extracting from an image information in a form suitable for computer processing NOTE : Often this information bears little resemblance to visual features that human beings use in interpreting the content of an image. Application areas include: – – Automatic Optical Character Recognition Machine vision for product assembly and inspection Military recognizance Automatic fingerprint matching etc. IT 523 - Digital Image Processing 7

Segmentation Representation and Description Preprocessing Outside world Knowledge Base Recognition and Interpretation O/P Image Acquisition The Digital Image Processing System The DIP system takes inputs from the outside world and produces desirable (application dependent) outputs. IT 523 - Digital Image Processing 8

Questions? IT 523 - Digital Image Processing 9