3.4 Image editing with GIMP

Resizing images

Activity 1: Change the Size of an Image (Scale)gimp-open

(use the image: "children.jpg" available as a resource)

This image is huge and you need to scale it for viewing on a webpage.

  1. Start GIMP


  2. Open the image "children.jpg" with GIMP: click on File, Opengimpchildren
    You might notice that GIMP opens the image at a logical size for viewing. So, if your image is big like the sample image, it will display it zoomed out until it fits. You can tell if GIMP has done this by the percentage number in the title bar. (you can click on the little screenshot to see the full view of the screenshot) Just because it looks right in this "View" doesn't mean anything.




  3. Right click on the image, select "Scale Image...". This time, you should get the "Scale Image Dialog".gimpscale
    If you have a desired width, put it in the dialog. If you don't have such a number in mind, put the width of GIMP's default image size, which is 256 pixels.











  4. Let GIMP choose the other dimension length for you.gsd2
  5. Select "Scale"






  6. Save the resized image as "children256.jpg"

Saving as JPEG - Quality

When you save a file in JPEG format (extension .jpg, .JPG, or .jpeg.), a dialog is displayed that allows you to set the Quality level, which ranges from 0 to 100. The default quality of 85 usually produces excellent results, but in many cases it is possible to set the quality substantially lower without noticeably degrading the image. You can test the effect of different quality settings by checking Show Preview in image window in the JPEG dialog.