Monday, September 21, 2015

image manipulation

Day 1

Discuss:

Learn:

  • Image Manipulation & Chroma Key 
  • Take at least 4 photos on green screen. We'll work with those next time. In the meantime...

Chroma Key with GIMP
  • Find an appropriate image to put santa hat into. Use Creative Commons Search. Save background on your computer.
  • File -> Open, background image. Check out the dimensions.
  • Download the green screen image below.
  • File -> Open green screen image.
  • Layer -> Transparency -> Add Alpha Channel
  • Repeat following steps until most of the green is gone:
    • Use Select by Color Tool and select green color
    • Edit -> Clear
    • Select -> None
  • Get rid of any remaining green with eraser tool
  • You may want to save file at this time, so you can try it out on multiple backgrounds.
  • Use Magic Wand and select transparent region around hat.
  • Select -> Invert Selection.
  • Edit -> Copy.
  • Now open background image.
  • Edit -> Paste as New Layer.
  • Adjust position & size of hat as needed.
  • Save this file as a .PNG or .GIF file.
  • Upload to your blog.


Day 2:

Discuss:


Image Manipulation & Ethics - What happens when photoshopping goes too far?

Learn

  • Open green screen image with GIMP.
  • Layer -> Transparency -> Add Alpha Channel.
  • Repeat following steps until most of the green is gone:
    • Use Select by Color Tool and select green color
    • Edit -> Clear
    • Select -> None
  • Get rid of any remaining green with eraser tool
  • Use Magic Wand & select transparent area. 
  • If you see artifacts selected in the transparent area then select Select -> Invert. Use eraser on those areas. Repeat this step until no more artifacts remain in transparent area when you select it.
  • Select Select -> Invert
  • Select Edit -> Copy
  • Find an appropriate background. Use Creative Commons Search. Save background on your computer.
  • Open background image with GIMP.
  • Select Edit -> Paste as -> New Layer.
  • If you image is too large, select Scale Tool and use corners to shrink.
  • Use Move Tool to move image to where you want it.
  • When it’s ready, select File -> Export As and save as .PNG file. 

Reflect:

You can choose to share your creation on your blog. If you do post it, be sure to credit source for background image & write a reflection about your rationale for why you are comfortable sharing online. If not, please e-mail to me and write a reflection about your rationale for why you are not comfortable sharing.


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