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Gifted and Talented Education Programme

Introduction to Image Manipulation:

To develop student’s knowledge and skills in “Visual Arts” the students were shown how to use a GNU Image Manipulation Program to create and manipulate digital images.

Essential Skills:

  • Communication
  • Problem-solving
  • Social and Co-operative
  • Computer
  • Problem Solving

Students Learnt to:

  • Understand basic graphics terms and concepts.
  • Download pictures from a camera onto a computer.
  • Search and download Royalty free images.
  • Various effects and technics that are produced by manipulating stored pictures using Gimp computer software.
  • Save their work in different image formats on the computer.
  • Print their manipulated images on a printer at school.
  • Display images in computer suite and/or school foyer.
  • Present their work at school assembly.
  • Express their artistic ideas.

Basic Terminology

Students completed a web-quest looking for the meanings for some basic graphics terms that they would be using.


An image is a visual representation of something.

Image/Photo Manipulation

Image and photo manipulation is the application of image editing techniques to photographs or images in order to create an illusion or deception after the original photograph or image.


In traditional typography, a font is a particular size, weight and style of a typeface.


Generally deals with line arts. Mostly created with Gif format where line of the picture is more important than color. Cartoons, icons and sometimes buttons also comes under this category.


Resolution is the amount of detail an image holds. The higher the resolution the more detail the image has.

File Formats

A file format is a standard way that information is encoded for storage in a computer file. The common formats for images are Png, Jpeg and Gif.


The word "pixel" means a picture element. Every photograph, in digital form, is made up of pixels. They are the smallest unit of information that makes up a picture. Usually round or square, they are typically arranged in a 2-dimensional grid.

Project 1 - Changing at photos Background

This was the first time that most of the students got to use GIMP, so this needed to be a simple project but would test their patience because of the amount a time it was going to take to select their image.

Students took photos of each other against a plain background which was to be manipulated later using the image manipulation software "GIMP".


  1. Open image in GIMP
  2. Use paths tool to create a selection around themselves then invert the selection which enables them to delete the background leaving just themselves.
  3. Search google images for a suitable background and save to their folders
  4. Add saved background image as a new layer
  5. Put new background layer behind first layer
  6. Move the selection of themselves.
  7. Print their manipulated photograph.

Before and After

Archie with replaced background in amongst guards. Original background Archie with replaced background in amongst guards. New background

Project 2 - Funky Eye Colour

The main object of this project was to take a picture of an eye and change the colour of the iris.

The students were allowed to use images from the internet that were free to use or copyright free. They were also allowed to take the photos themselves.


  1. Open image in Gimp
  2. Duplicate the image layer and add alpha channel to background layer
  3. Uncheck eye on layer 2
  4. Use path tool to select iris of eye use path to selection
  5. Invert selection and delete the rest of the image/photo
  6. Use Ellipse Selection Tool to select middle of eye and delete
  7. Use Paths selection
  8. Select Blend tool use tools options
    • Gradient
    • Full saturation spectrum
    • shape
    • Conical (sym)
    • Draw a line from middle of eye to edge of eye
    • check eye symbol on layer 2
    • Uncheck eye symbol on layer 1
  9. Use Ellipse Selection Tool to select middle of eye
  10. Uncheck eye symbol layer 2
  11. Select and check eye layer 1 then delete
  12. Change mode on layer window to Overlay
  13. Export image as .png image
  14. Print finished image

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Before and After

Sample image of an eye. Original Image of an eye. Large sample image of an eye. Rainbow Coloured Eye

Once they had completed the changing the eye colour, they were allowed to explorer other techniques.

Adding an Image

The next example was created by Lily, she had used a image of exploding fireworks as the iris colour.

Lily's fireworks coloured iris. Manipulated Image

Project 3 - Bokeh (Blurred Background)

In photography Bokeh makes photographs visually appealing, forcing us to focus our attention on a particular area of the image.

For this project the students were asked to take a photo of an object then using GIMP blur the background to give the same effect as a if a photographer had taken the photo.


  1. Students take an photo
  2. Download photo to their folder
  3. Open photo in GIMP
  4. Duplicate photo
  5. Add alpha channel
  6. Use path tool to select main subject
  7. Invert selection and delete background
  8. Deselect eye symbol for layer 2
  9. Use path tool selection to delete main subject on layer 2
  10. Click on menu bar Filter/Blur/Gaussian blur
    • Blur Radius
    • Horizontal 5
    • Vertical 5
    • Repeat Gaussian Blur until required effect achieved
  11. Save and print completed image

Before and After

Original image no bokeh. Original Image Large blurred background image. Manipulated Image

Once they had completed the changing the eye colour, they were allowed to explorer other techniques.

Project 4 - Out of Bounds Image

Students used a technique that makes an image appear to burst out of a photos frame. This technique uses all of the tools the students had used in previous projects but also uses a few they hadn't used before so still giving them a bit of a challenge.


  1. Students will take an action photograph or search for an free to use or copyright free image on google images.
  2. Download to their folder
  3. Open Image in Gimp and add alpha channel
  4. Duplicate image and add alpha channel
  5. Create new layer
    • Colour - Black
  6. Move below image layer
  7. Select part of main subject with path tool to be outside frame
  8. invert selection and delete background
  9. Deselect eye symbol layer 2
  10. Add new layer
    • Add alpha channel
  11. Use Rectangular Selection tool to delete the middle of layer 30pixels from edges
  12. Select none
  13. Use Perspective tool transform the layer into a frame around the photo
  14. Select layer 2
  15. Use rubber to remove background not in the image frame
  16. Select frame layer and use rubber to remove parts of frame that shouldn’t be seen
  17. Save image as .xcf
  18. Export image as .png and print image

Before and After

Thumbnail original image of a soccer player kicking the ball. Large original image of a soccer player kicking the ball. Original Image thumbnail of manipulated image of a soccer player kicking the ball.Large manipulated image of a soccer player kicking the ball.Manipulated Image