DIGITAL IMAGE PROCESSING

DIP

معالجة الصورة الرقمية

LEC (4)

PART -A

IMAGE ZOOMING & SHRINKING

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د.زينب محمود عمر

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���IMAGE RESOLUTION

Resolution refers to the number of pixels in an image. Resolution is sometimes identified by the width and height of the image as well as the total number of pixels in the image.

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For example, an image that is 2048 pixels wide and 1536 pixels high (2048 x 1536) contains (multiply) 3,145,728 pixels (or 3.1 Megapixels).

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Below is an illustration of how the same image might appear at different pixel resolutions, if the pixels were poorly rendered as sharp squares (normally, a smooth image reconstruction from pixels would be preferred, but for illustration of pixels, the sharp squares make the point better).

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Zooming and shrinking digital image

• Zooming

Zooming requires two steps:

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1. Creation of new pixels locations.

2. Assignment of gray levels to those locations.

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2. Bilinear interpolation�

• Bilinear interpolation replaces each missing pixel with a weighted average of the nearest pixels on the boundary .

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• In blurring, we simple blur an image. An image looks more sharp or more detailed if we are able to perceive all the objects and their shapes correctly in it. For example.

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• An image with a face, looks clear when we are able to identify eyes, ears, nose, lips, forehead e.t.c very clear.

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• This shape of an object is due to its edges. So in blurring, we simple reduce the edge content and makes the transition form one color to the other very smooth.

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IMAGE SHRINKING

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SOLUTION

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