(Note: this is intended to be a generic method)
To go from this: ...to this:
- Open the image you want to remove the background from. If it is a *.gif, you may need to select all the image and then copy the image data into a new document to edit it. This will be necessary for the image above.
- Create a new layer in the document, so that you have two layers (One blank one and one containing all the image data you want to keep). Alternatively, press ctrl-shift-N and enter a name for the new layer.
- Make sure the new layer is at the bottom of the layers window.
- On the left hand side, click on the button labelled "Primary colour palette" above, and select a colour that will be easy to distinguish from the image. For this image, red will be used.
- Press ctrl+g to select the "paint bucket" tool- it will fill any selected area with colour.
- Make sure the blank layer is still selected, and click anywhere on the canvas. You should not see any change except for the icon for the blank layer changing colour.
- Select the image layer now.
- Select the "Magic wand" tool (labelled above). Alternatively press "W".
- On the top of the window, you should see a number next to "Tolerance". Set it to 10.
- Click on an area of the image you want to remove. If areas of the image you don't want to remove are selected, press ctrl+alt+Z to undo the step. Choose a lower value for the tolerance and repeat.
- If you have only an area you no longer wish to keep, hit delete. You should see the background colour showing through now.Select another area by clicking on it. Seen below is an example of one part of the image removed.
- Continue until there are no areas left to remove. If there are parts with a lot of changing colour, then you will probably be better off using the "Polygonal Select" tool:
- Press "L" or click on the button labelled above.
- Make sure that "Feather" has a value of 0, otherwise you will have areas of the background kept.
- Trace round the parts you want to keep by placing points at regular intervals, making sure you use more where the shape changes a lot.
- Join up the end of the tracing, so that only the parts you want to remove are selected.
- Press delete.
- Continue until all areas you want to remove are gone.
- Once you have removed all the areas you no longer want, toggle the transparency of the background layer (the eye next to the layer). All the areas of the image that were the colour of your background layer should now look like a grey checkerboard (see below).
- If you only wanted to remove parts of background to make them transparent, you are done. Click "File"->"Save as..." then select ".PNG" from the dropdown menu. Click "Save" and select "None", then click "OK". Congratulations, you now have a high quality PNG with transparency! Uploading and linking the file in IMG tags on the forum will make all the transparent areas come up with the background colour.
- If you want to use the image on the forum as an avatar, you need to follow one more step. Click "Image"->"Image Size". Then on the next screen make sure "Constrain proportions" is turned off. Enter 100 for both the width and the height. Hit ok, and then follow the previous step to save. Note this works best with square or almost square images as it will stretch them if they are not.
Any questions, PM me.