Skills: rotate, select, crop, resize, change contrast, filter, compressConcepts: image processing operation, information
This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 License.
An image processing session
Where does this topic fit?
• Internet concepts– Applications– Technology– Implications
• Internet skills– Application development– Content creation (image)– User skills
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
Start with a picture of Lucas
2,048 by 1,536 pixels (zoom out to fit laptop screen)
Operation: rotate
Operation: crop
357 by 381 pixel image (shown full size)
Operation: adjust contrast
Operation: apply the “ink sketch” filter
Operation: resize
200 by 213 pixels
Operation: crop
200 by 200 pixels
Tool option and status areas
15.3 kilobytes40.2 kilobytes
Operation: compress
Image processing work flow
Capture
Edit
Compress
Distribute
Try this for yourself
The original picture of Lucas is at:
http://som.csudh.edu/fac/lpress/netApps/image/lucasoriginal.jpg
Zooming versus resizing
2,048 by 1,536 pixels (3 megapixels)
1,920 by 1,200 pixels
Summary
Resources
Tutorials:http://www.getpaint.net/doc/latest/index.html
Download, forums, blog and email contact:http://www.getpaint.net/doc/latest/WebLinks.html
1. We illustrated several image processing operations in this presentation. Without looking back, do you recall what they were?
2. Can you describe what each does to an image?3. Can you think of any other image processing operations that we did not use in
this presentation?4. If one zooms in on an image is information lost or gained?5. If one resizes an image, making it smaller, is information lost?6. If one resizes an image, making it larger, is information gained?7. If one crops an image, is information lost?8. If one filters an image, is information lost?9. If one compresses an image, is information lost?10. If one zooms in on an image, which of its characteristics are changed?11. If one resizes an image, which of its characteristics are changed?12. If one crops and image, which of its characteristics are changed?13. If one filters an image, which of its characteristics are changed? 14. If one rotates an image, which of its characteristics are changed?15. If one compresses an image, which of its characteristics are changed?
Self-study questions