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  Building
  Making a masked picture with Gimp (1)
 
A masked picture is a picture which has been cut out of an image and all the surrounded parts have been made totally or partially transparant.
We are using the freeware texturing program Gimp for this tutorial. Goto the website http://www.gimp.org where you can download this program.
 
The pictures of this tutorial is in dutch, because Gimp installs the program in you own language. But explanation here will be in english, so it won't be a problem for this tutorial.
You can also find hundred of tutorials on Youtube if some things aren't clear enough.
 
Once installed, you start the program Gimp
First you make visibile these 2 windows : for the Toolbox and the Layers. If not visible, go to the menu Windows and make the windows visible again.
 
Now browse for the image you want to cut out as a mask : File - Open
In this example it will be this osteospermum flower.
We click upon the rectangular selection tool . We will now cut out the image , so that the flower gets into the center of the image.
Now press CTRL+C, so we copy the selection.
Edit - Paste as : new image (= Shift CTRL+V)
On the right side, you also see the layer with the flower image.
 
* remark : you can also crop the image after you have cut out the flower ,by using in the menu : Image - Auto Crop Image .
Method 1 - The Fuzzy Select Tool + Erase Tool

The first method that we will use is the Fuzzy Select Tool (this is similar to the Magic Wand Tool of Paint.net or Photoshop).

If the background would be in 1 color, e.g. black background, then it is simple : the flower will be immediately selected. But in this example you have to delete the leaves....
We double-click upon the Fuzzy Select Tool ,and you will see the options for this tool. Now you move the Tolerance level. The higher the tolerance, then most shades will be selected, so choose a low tolerance, you that we do not select any parts of the flower itself. Here we choose for instance a tolerance of 30 percent.
Now click in the image on the parts around the flower and press the Delete key.
If the Furry Select Tool selects anything of the flower itself, then undo the selection.
After a while almost all big parts around the flower will be removed. And you will notice that it is difficult to erase the remaining parts.
Now use the Erase tool (rubber) and we erase the remaining small parts.
Now we will zoom in : press the CTRL key and scroll with the mousewheel.
Now we move the image : press the Spacebar and drag with your mouse. You can also scroll the bars at the bottom and the side , or scroll with the mousewheel to go up or down. Now we can accurately continue with the erase-tool and Furry Select Tool in each corner of the image.
When you are ready, then choose : File - Export As
Now browse to the location where you want to save the file.
At the top of this window you type the filename : osteo1.png
Choose extension .png, otherwise you won't have a transparent background, and click upon Export.
Now a window will appear with options : deselect all the options and choose Export.
And your masked picture is ready to be used.

Method 2 - The alpha Channel + Erase Tool
 
You can also make this flower by first creating a transparant layer :
Go in the menu to : Layers - Transparency - Add Alpha Channel
And in the layers window you see the transparent layer (indicated in checkerboard).
Now use the Erase Tool and remove de background parts around the flower.

For the more accurate work around the edges, use the CTRL+mouswheel to zoom in. Then double-click upon the Erase Tool to see see the options, and edit the brush size of the erase tool .

When finished, export the image as .png file.
Method 3 - Color Treshold
 
For this method , we will use a daisy flower. File -Open - select daisy.jpg
We enlarge the picture : press CTRL and scroll with your mousewheel.
We will copy the layer by clicking up the duplicate button in the layers window.
Then we select this duplicated layer (copy = top layer).
Go in the menu and choose : Color - Treshold.
Now you have a black&white image , and by moving the slider , you can determine which colours belong to the foreground and which to the background, so that you can clearly see the edges.
Now select the Paint Brush Tool.
And then select the black rectangle, the small white arrow makes it possible to switch between black and white. Now select black color.
You can modify the brush size and sharpness of the brush. (double-click upon the brush in order to see those options).
Then you can start making the parts around the daisy-flower in black.
Now you switch the color to white, so that the white rectangle is in the foreground.
Now we use the brush to make the central area of the daisy flower white.
Then reduce the brush size and also remove the black spots from the flower leaves.
Now click upon the Select by Colour Tool and then you click anywhere on the black background and you will see that the background is selected.
Now go to the layers menu, and select the image (instead of the copy) .Right-click upon the image and select in this menu : add Alpha Channel .The Alpha Channel gives to the image a transparent background.
Select again the "copy" layer (the black&white layer).
We remove this layer by pressing the delete button.
 
Now we see the original image again, but we see that area around the flower is selected.
Press the delete key and the background will be deleted and we now we see the flower with a transparent background.
Now we deselect by choosing : Select - None.
We could already use this image as png, But there is still some touching-up.
We will create again a black background for this.
We go to the layer window and click upon the Create Layer-button.
Now a window opens with title "New Layer".
Make sure that the black rectangle is selected .(= switch to black).
And for Layer Fill Type , we choose: Foreground Color. And click OK.
 
In the layer menu, you will see this new black layer and we will move it down, but clicking upon the green down-arrow icon. Now we see the flower image with black background.
We zoom in (CTRL + mousewheel). We choose again the Select Color Tool , and we go to Treshold and choose a color range e.g. 15. The higher the range the more colors will be selected. We go to the layers window and select the image layer.
Then we click upon a remaining green area, and all the green areas will be selected.
Choose the Erase Tool and remove (=replace by black color) the selected areas that you want to erase.
When everything is ok, you remove the black layer again ,and the flower with transparent background remains. If you don't want any background around the flower, then choose in the menu : Image - Auto Crop Image
Finally you can export the image as a png-file.
Method 4 - The Path Tool (Pen Tool)
 
For this method , we will use a maple leaf. We open the .jpg file.
Fist we cut out the image, so that image is a bit more square.
We zoom in with the CTRL + mousewheel.
Now select the Path Tool , we will cut out the image, by making a path along the edges of the leaf. In the Path Tool options, we start with the "design" of the path.
We start at the stem of the leave and start clicking alongside the border. Each time you click, you will see an new anchor point (white ball) along the path.
If you made a mistake, then type CTRL+Z and continue again with the path.
When you have finished, then click again upon the first anchor point of the path.
Now we start to modify the path : in the Path Tool options, now we choose "Edit"(ctrl).
Go to the path lines and by clicking upon the lines, you add new anchor points.
You can modify straight lines into curved lines by grabbing with the mouse.

When you want to put 1 anchor point of the path a bit more to the border, select again "design", and move the anchor point to the correct place. You will also notice that you can modify here the curved lines as well. Don't choose the "move" button, because this will move the entire path.

Then choose "edit" again to continue with modifying.
So it's a constant switching between "edit" (to add new anchor points) and "design" (move the anchor points and make curved lines).
When you have finished with the whole path, then go the the Path Tool options, and click upon "Selection from Path". And there will be added dotted lines to the path.
Zoom out and you will see all the anchor tools.
Now choose in the menu : Edit - Copy. (or you can use : Edit - Cut)
And then : Edit - Paste as : New Image. Now you have the leaf with a transparent background. The last step that remains is to export the image.
File - Export as : mapleleaf.png (extension png)
Method 5 - The Free Select Tool (Lasso Tool )
 

This method looks similar to the Path Tool .

We start wil loading the picture , here a red rose. Then we click upon the lasso tool and we start punt anchor points alongside the edge of the flower,not quite like we did with the Path Tool, here you must be sure that the anchor points are made rather around the flower, and not inside the flower, because after cutting out, you cannot edit/move the lines and put back a piece of the flower.
When you have finished with putting anchor points around the flower, you join the last anchor point with the first anchor point ,the anchor points will disappear and you will see immediately a dotted line around the flower.
As we have told, you cannot do any editing work with the Lasso Tool. For this we will use other editing tools.
Now that the flower is surrounded by a dotted line.
We do next : Edit - Copy And then : Edit - Paste As : New Image.
Now we have the flower with the transparant background , and now we can start doing the editing work.
Use the CRTL + mousewheel to zoom in, and then use the Erase Tool (Gum), and we erase carefully the dark lines around the flower. You can also lower the size of the Erase Tool, so that the adjustments are more accurately. (e.g. size 5 instead of 20)

When you have finished with that, then click upon the Fuzzy Select Tool (=Magic Wand) and you click in the background and press the delete key. Or if you see any dotted lines inside the transparent background, use the Erase Tool to remove them.

Finally, you choose : File > Export as : redrose.png.