An image processing session

An image processing session

Skills: change view, rotate, select a portion of, crop, resize, change contrast, filter an image, undo an operation

IT concepts: pixel, image processing operation

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Image processing in context

• Internet concepts– Applications– Technology– Implications for

• Individuals• Organizations• Society

• Internet skills– Application development– Content creation

• Text• Images• Audio• Video

Selected image processing operations

• Rotate an image • Crop an image• Change image contrast• Apply a filter to an

image• Resize an image• Select a portion of an

image

Let’s apply these to an image.

Start with a picture of Lucas

2,048 by 1,536 pixels (shown reduced to fit the slide)

Zoom in to see pixels

Changing the view does not alter the image, just what you see while working on it.

Operation: rotate

1,536 by 2,048 pixels (shown reduced to fit the slide)

Operation: crop

357 by 381 pixel image (shown full size)

Operation: increase contrast

Operation: apply the “ink sketch” filter

This sort of thing took an overnight run in the era of batch processing.

Image processing programs have many such filters.

Operation: resize

50 by 53 pixels

This could be used for an icon on a Web site or in a program.

Operation: resize

200 by 213 pixels

I want to make a 200 by 200 pixel head shot to fit a Web site.

Operation: crop

200 by 200 pixels

Ready to insert into head-shot space on the Web page.

Try this for yourself

The original picture of lucas is at:

http://bpastudio.csudh.edu/fac/lpress/netApps/image/lucasoriginal.jpg