5 handy tips with GIMP everybody should know

Adobe Photoshop is undoubtedly the most powerful tool for graphic works. However, if you dont need to make something serious, Good Guy Gimp is already really enough for most of the basic tasks ( and you can use Gimp for serious graphic works too). In this article, I will show you several tips with GIMP that are very handy.

1  - Crop an image

The Crop tool is located near the Text tool. Its icon is a paper cutter. To crop an image, just click the Crop tool, drag your mouse on the image to select the crop area then click inside the selected area and this area will be cropped out.

2 - Make the background of an image transparent

Lets take this image of Son Goku as the example:

5 handy tips with GIMP

To make the background of this image transparent, you open it with GIMP. Use the Fuzzy Select tool to select the region around Son Goku.

Next, on the Menu bar, click Layer > Transparency > Add Alpha Channel, this will store transparency data into the image. Next, hit the Delete button and you will have something like this:

GIMP handy tips

Do this again to remove all the white parts inside the image then save the file as a .png. You now have a new image with a transparent background.

3 - Crop an image with rounded corners

This is very useful if you want to design buttons and icons. To crop and image with a rounded corners, you select the whole image. Then on the Menu bar, click Select  > Rounded Rectangle , a dialog box will appear to ask you to select the radius angle, 50 is the default value but 15-30 look the best:

useful GIMP tips

After selecting the radius, right click on the image then Select > Invert:

GIMP tips

Then hit the Delete key and the 4 corners will be cropped out, replaced with a white background. You can also use the #2 tip to make this white background become transparent:

5 handy tips with GIMP everybody should know

3 - Remove the red eyes

The bloody red eyes happen when you use flash to take photos. To remove the red with GIMP, you select the red area first then one the menu bar, go to Filters > Enhance > Redeye Removal. Select the Threshold and when you click OK, the red eye will become black eye.

4 - Change the size of an image

To change the size of an image, one the menu bar, go to Image > Scale Image. On the dialog box, you will see the dimension values for you to change. There is also a link between the two dimensions, click on this link to break or connect the link between 2 dimensions. If you dont break the link, one dimension will be adjusted accordingly if you change the other one:

5 - Reduce the file size of an image

If you want to save time when uploading images, its recommended to reduce the file size of the images. To do so with GIMP, open up the image you want to reduce, now go to menu, File > Save As and hit the 'Save' button. Now drag the slider in the pop up box to any level you want. Check mark the file preview box to get a live preview. The less size you want the less this number should be. But remember that lower size means less quality.
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