For most people, digital media is a part of your everyday life. But we don’t always think about how it is created.
If you want to better understand how content moves from the mind to the monitor, continue reading for an introduction to Bitmap images.
What Is Bitmap?
“Bitmap” images are created by arranging a grid of differently colored pixels. When viewed from a distance or at a small scale, the images appear natural. But, if viewed up close or when the image is enlarged, they appear blurry and “pixelated.”
This method can create any 2D rectangular image. More than that, a rectangular image created using bitmap can be copied and pasted repeatedly to quickly and easily cover a vast area with a similar repeating pattern, known as a “tilemap.”
Limitations to Bitmap Design
The only real limitation to bitmap design is file size. Creating crisp and highly detailed images requires a higher number of “bits.” This can mean that these images take up a great deal of computing space.
Furthermore, an image cannot effectively have a higher resolution than the screen that it appears on.
To understand the limitations of display and bitmaps, put your eye very close to your screen to see “the screendoor effect.” This is the grid pattern that appears on digital images due to the space between pixels. It’s a big topic in virtual reality because of how close the display is to your face, but it’s actually a factor in any digital display.
Why Bitmap Has a Special Place in Our Hearts
“8-bit” videogames and graphics are good illustrations of bitmap design. Be careful, though. 8-bit doesn’t refer to the resolution. It refers to the memory that each pixel requires.
More “bits” really just means more color options. This comes into play with “retro” or “8-bit-style” games made with modern designs for modern displays, like Minecraft.
While bitmap images are only as old as digital displays, the same way of constructing images from discrete points has been used for decades. The print version of a bitmap, called a “dot matrix,” was used in image printing for decades. Just like some videogames deliberately replicate 8-bit graphics, some comics deliberately maintain dot matrix.
Bitmap vs. Vector
The main alternative to bitmap design is “vector image design.” Rather than being created through a point grid, the boundaries of vector images are defined mathematically. The result is images that can be scaled up almost infinitely without a loss of image quality.
The ability to scale the image is a huge benefit over a bitmap, but that’s more or less where the benefit ends. Vector images are harder to create from scratch, and a lot is lost in the design process. Further, it is hard to make a vector image that can be stylistically replicated in the same way that a bitmap can be used for a tilemap.
As a result of these limitations, most vector images are actually created by making a bitmap image and converting the file.
Finally, vector images are limited by display definition in the same way that bitmap images are. No matter how detailed your vector image is, it cannot appear in a higher definition than the user’s device or display settings allow.
Appreciating the Humble Raster
Sometimes, a bitmap isn’t the best method for displaying an image. However, this method of creating an image with a grid of colored pixels remains the best way to actually create digital images.
Even if you aren’t in the design field yourself, knowing the work that goes into bitmap image creation and the feelings it evokes can increase your appreciation of this iconic digital medium.
About The Author
