Transparent Background and Bleeding

Posted on 2011-10-27
Last Modified: 2013-12-02

I'm hoping someone can help me with a question regarding creating a transparent background or setting the background without bleeding using the Gimp. Below is part of the image I am dealing with.

 corner of bitmap
What I need to do is to make the background (the white area) another colour as I am adding this to a Windows Form application in which I can make that colour transparent e.g. if I made the background RED then I could tell the application to make RED transparent. In doing this I can make non-rectangular windows!

The way I have done this in the Gimp is as follows:

(1) Load the image into Gimp.
(2) Use the magic wand to click the white background. This selects the background around the main image.
(3) I then use Layer->Transparency->Add Alpha Channel.
(4) Edit->Clear.
(5) I then fill the removed background using a particular colour e.g. RED.

This almost works but the problem I have is that when I use the graphic and run the application there is a slight red edging around the image. I can only assume that when I have filled the background with RED then it has somehow merged into the edge of the graphic.

Does anybody have any ideas how I  can avoid this?

Question by:IssacJones
    LVL 30

    Accepted Solution

    Have you tried different values for the Threshold parameter when using the Fuzzy Select (Magic wand) tool? Here are 2 examples with different values of Thresshold: Value 125 Value 110

    Author Closing Comment

    Many thanks!!!

    Featured Post

    Top 6 Sources for Identifying Threat Actor TTPs

    Understanding your enemy is essential. These six sources will help you identify the most popular threat actor tactics, techniques, and procedures (TTPs).

    Join & Write a Comment

    I. Introduction In a previous article ( (now deprecated), I discussed how to upgrad…
    PaperPort is a popular document imaging/management product from Nuance Communications ( It is in widespread use by both individuals ( and businesses (http:/…
    The goal of the tutorial is to teach the user how to edit a basic portrait of someone. This tutorial shows how to edit two basic photographs, one of a car and one of a person.
    The goal of the tutorial is to teach the user how to make his/her own presets while editing so it is easier to edit there photos. Create a preset you like and copy that setting then save it in to your presets folder.

    728 members asked questions and received personalized solutions in the past 7 days.

    Join the community of 500,000 technology professionals and ask your questions.

    Join & Ask a Question

    Need Help in Real-Time?

    Connect with top rated Experts

    18 Experts available now in Live!

    Get 1:1 Help Now