Billy Lopez is a Designer at Fat Pencil Studio
Digital images are comprised of many dots arranged in a grid formation. When viewed together without magnification, they give the appearance of a single continuous tone image. This grid is sometimes described as "raster format" with each dot or square containing containing a color value. Depending on the resolution, each image can contain millions of individual pixels. For example a "4k resoultion" image has a grid of 3840 pixels wide by 2160 pixels high, which is about 8.3 million pixels.
What is seen
Digital color is considered additive. A zero value for a pixel is black, which we can change by increasing the specified amount of three different color channels: red, green, and blue, also known as RGB. Additionally a digital image can specify a transparency value, also known as alpha. The default is 100% opaque if no alpha channel is present.
Pixel color data
The most common format for storing color data is called "24 bit" color because it contains 8 binary numbers for each of the three RGB channels. Converted to base-10 decimal numbers, this allows for 256 unique values per channel.
By combining different color intensities for each channel, we have the potential for millions of unique colors in a single image. These RGB values are designed for use with the light emitting diode (LED) technology used in modern display devices, which will be covered in a future post.
