1. An image processing session Skills: change view (zoom in or out), rotate, select a portion, crop, resize, change contrast, filter, compress IT concepts: image processing operation This work is licensed under a Creative Commons Attribution-Noncommercial- Share Alike 3.0 License.

2. Where does this topic fit? Internet concepts –Applications –Technology –Implications Internet skills –Application development –Content creation (images)

3. 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, ending up with a 200 by 200 pixel head shot.

4. Start with a picture of Lucas 2,048 by 1,536 pixels (shown reduced to fit the slide)

5. Operation: rotate 1,536 by 2,048 pixels (shown reduced to fit the slide)

6. Operation: crop 357 by 381 pixel image (shown full size)

7. Operation: increase contrast

8. 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.

9. Operation: resize 50 by 53 pixels This could be used for an icon on a Web site or in a program.

10. Operation: resize 200 by 213 pixels I want to make a 200 by 200 pixel head shot to fit a Web site.

11. Operation: crop 200 by 200 pixels

12. 15.3 kilobytes 40.2 kilobytes Operation: compress

13. Tip for Web developers Capture images (or audio or video) at the highest resolution possible. Do all resizing, cropping, contrast modification, etc. on the high resolution image. The last step is compression (if any) and uploading the image to the Web.

14. Try this for yourself The original picture of lucas is at: http://bpastudio.csudh.edu/fac/lpress/netApps/image/lucasoriginal.jpg

15. A few questions

16. We illustrated several image processing operations in this presentation. Without looking back, do you recall what they were? Can you describe what each does to an image? Can you think of any other image processing operations that we did not use in this presentation?

17. If one zooms in on an image is information lost or gained? If one resizes an image, making it smaller, is information lost? If one resizes an image, making it larger, is information gained? If one crops an image, is information lost? If one filters an image, is information lost? If one compresses an image, is information lost?

18. If one zooms in on an image, which of its characteristics are changed? If one resizes an image, which of its characteristics are changed? If one crops and image, which of its characteristics are changed? If one filters an image, which of its characteristics are changed? If one rotates an image, which of its characteristics are changed? If one compresses an image, which of its characteristics are changed?

19. An image processing session Skills: change view (zoom in or out), rotate, select a portion, crop, resize, change contrast, filter, compress IT concepts: image processing operation This work is licensed under a Creative Commons Attribution-Noncommercial- Share Alike 3.0 License.