President Obama’s long-form birth certificate has been scrutinized extensively from the moment it was released. Many people have claimed that the document is a forgery, based on issues such as chromatic aberration and a difference in pixel sizes, among other things. So, what is a pixel anyway, and what do pixels have to do with the authenticity of this document?
What is a Pixel?
The term “pixel” is shortened from the words “picture” and “element.” Simply put, it means a single, monochromatic element of an image. Think of the pixel as a single tile in a large mosaic. Whatever you’re looking at on your computer screen is actually composed of these tiny spots in massive numbers. President Obama’s birth certificate was scanned into a computer and is available as a digitized image, and therefore is composed of a number of pixels.
Why Does Pixel Size Matter?
In the most elementary terms, when you put a document into a scanner, the scanner takes a picture of the document and saves it to your computer. You can then open the image using a variety of different editing programs, such as Adobe Photoshop, for example, or even Paint. When you open the scanned document, and zoom in, you will see that it is composed of small blocks of color. Each block is the same size, but the different colors and shades blend together to show the picture when you zoom out.
The majority of the document is composed of larger pixels. The layer of pixels that is easily removed from the document with Adobe, however, is composed of much smaller elements. As you can see in the dramatically-magnified example to the right, with lines added to emphasize the pixel borders, pixels in some of the text areas are 1/4 the size of the background pixels. This sample is taken from the upper portion of the “AR” in BARACK, Block 1a.
There are a few things to consider, when looking at the change in pixel size between the two types of lettering. The first anomaly is that the smaller pixels are only present in certain areas. The second is whether the borders of the smaller pixels match, and align with, the larger pixels.
Where are the Pixels Different?
The smaller pixels are present only in the main text layer, and the halo around that text layer. An extreme zoom of the document shows that the pixels of monochromatic dark text, which shows the appearance of optimization using a threshold algorithm, are in the smaller size. The light-colored pixels surrounding the darker text, also subject to a threshold algorithm, are the smaller size as well.
Do the Pixels Align?
If you take note of the grid-lines of the image to the left, taken from the underside of the “A” in BARACK, with grid-lines added to clarify pixel boundaries, you’ll notice that the smaller pixels fit perfectly into the larger-sized pixels. This is indicative of computer manipulation, perhaps part of the optimization process, rather than editing by human hands.
Some portions of the text, however, do not align. The image you see here is a extremely magnified view of the top of the same “A.” As you can see, the pixels do not align precisely here.
The misaligned pixels are present in several areas, throughout the document.
What Does This Mean?
The fact that there are different-sized pixels throughout the document indicates, without a doubt, that the document has been altered from its original state. It is possible that the alteration is solely the result of a standard optimization process, but regardless – the presence of differently-sized pixels clearly indicates that the document is not an exact duplicate of an original document scan.
Check out Digital Document Authentication for more about the claims surrounding President Obama’s birth certificate.
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