Pixelating an image or photo can achieve an interesting effect for use in design or protecting a person's anonymity. Rather than placing a black bar over a person's face and detracting from the photo, you can pixelate a person's face to preserve their anonymity while maintaining the primary focus of the image. This simple effect can easily be achieved using the tools that came with your operating system, such as Microsoft Paint.
Open Microsoft Paint. Paint is found under "Programs," "Accessories" under the Start menu of most versions of Windows.
Open the image you plan to manipulate by going to "File," "Open" and navigate to the folder that contains the image. Press "Open" when you've selected the image.
Click the Select tool (this looks like a box with a dashed line border) and make a selection around the portion or all of the image that is to be pixelated.
Select "Resize" from the Images menu. In Vista's version of paint, this is "Image," "Resize/Skew," while in Windows 7 it is "Home" tab, "Image," "Resize."
Enter a small value for the vertical and horizontal resize values like "5." Click "OK." You'll see that the selected area has become tiny, exactly 1/20th of the original size.
Bring up the "Resize" window again and enter "500" for the horizontal and vertical values. This will increase the selection by five times.
Bring the "Resize" window up again and enter "400" for the horizontal and vertical values. This will increase the selection by four times. The selection now matches the original dimensions, but has made the selected area pixelated in a low-resolution.
Enter a large value for the vertical and horizontal values such as "50." Click "OK." This will reduce the size of the selected area by half.
Open the "Resize" window and enter "200" for the vertical and horizontal values. This will increase the selected area by two times.
Note that the pixelation done by halving the selected area and increasing it again by double results in tiny pixels.