How to Watermark Your Images Using GIMP

Here's the promised tutorial on Watermarking Images Using GIMP. Let's get right down to it.  Open GIMP. Click on the File tab -> Open -> Choose the image file you want to watermark

 It will open up a text box as shown in the image below.

Understanding The Text Box

1. In the picture above, the central rectangle is the actual text box
2. The 4 square corners are for moving the text box around the page. Place your mouse on one of these squares, right click, hold and try moving it up, down, left or right and see what happens.
3. In the image below,

• orange box 1 = Type the name of the font your prefer (eg. Times New Roman).
• orange box 2 = space between the lines of your text
• orange box 3 = space between the letters of your text
• red box = font size
• pink box = text box handle (this appears when you hover your mouse near any of the 4 walls of the text box)
• blue box = is where the text appears as you type it.

For a clearer understanding of these functions, play around and see what happens. First click inside the text box and then format the font.

But, unless I type in the text, I won't know how all these adjustments will reflect on my text.  So, I usually type in the text first. If you can't see what you're typing don't worry about it. Just check the layers area. Whatever you type will appear in the Text layer area in the layers tool box as in the image below.  (My Layer is on the left because I put it there. It's usually on the right side of the work area.) 

Now select the text by double clicking inside the text box. Edit font, text size etc. I want a diagonal watermark. To do that select the rotate tool. I've circled it in red in the image below. 

When you click on the text again, a mesh covers your text and a dialogue box appears as seen in the picture below.

Understanding The Rotate Diaglogue Box

Angle = the degree of rotation.

1.  If you add a positive value the text rotates clockwise.  
2. If you add a negative value, the text rotates counterclockwise.

For watermarking the image, we need to rotate the text counterclockwise. 

Think of the mesh you see as a graph sheet complete with an X axis and a Y axis and a center 0.

Altering the values of Center X and Center Y will re-position the center 0 and use that as the axis or anchor point for rotation. If you are not able to see the anchor point on the mesh, drag the dialogue box away from the mesh. You'll see a circle right at the center.  Watch it as you rotate the text.

Try adjusting the values of the Center X and Center Y counters and see what happens. Alternately, you can manually drag the center circle and drop it where ever you want.

Another way to rotate is to simply drag the mesh up from the right hand side or down from the left hand side and adjust the position.

You can place your text box at the bottom of the image letting it span the entire length of the bottom. Now you can drag and drop the anchor to the extreme left center of the text box, and then rotate.

Once you've rotated the image, you'll want it to look like a watermark rather than just text. To do this, choose 'opacity'  from the Layers area. Reduce the value until you're satisfied the text looks like a watermark.

Saving Your Watermarked File
We're done with the watermarking. Let's save the image. The screenshot below shows the save options in GIMP.

If you save in any of these file formats, you can open the image only with GIMP. So what do you do? From the file menu, choose export and select a file format.  I prefer to use .png as this retains image quality.  

Another saving option is 

Edit -> Copy visible

Open MS paint and paste image 

Crop if needed and save in .png format

One final point to note is, no matter what the file format, when compared to the original image, you'll find a considerable increase in the file size of the image you manipulated using GIMP.