Basic concepts of bitmaps, vector graphics, pixels, and resolution

Computer graphics are divided into two main categories: one is bitmap images, the other is vector graphics.

1. Bitmap images are technically called raster images, which are made up of pixels. It is characterized by the ability to perform color changes and nuances of color, to produce realistic results, and to be easily exchanged between different software. However, when you save, you need to record the location and color values of each pixel, and therefore occupy a large amount of storage space.

In addition, because of the resolution, the bitmap contains a fixed number of pixels, in its enlargement or rotation operation, can not produce new pixels, it can only enlarge the original pixels to fill the extra space, the result will often make a clear image becomes blurred.

2, vector graphics software through the mathematical vector method to calculate the graph, it is independent of the resolution, so can be arbitrarily scaled and rotated without affecting the clarity and smoothness of the graph.

Vector graphics occupy a much smaller amount of storage than bitmaps, but it does not create overly complex graphics and can perform rich color changes and subtle tonal transitions like bitmaps such as photographs.

Pixel-to-resolution relationship

Pixels are the most basic elements that make up a bitmap image. Each pixel has its own position, and records the color information of the image, the more pixels an image contains, the richer the color information, the better the image, but the file will increase.

Resolution is the number of pixel points that are contained within a unit length, which is usually in pixels per inch (ppi), such as 72ppi, which contains 72 pixels per inch. Resolution determines the granularity of the detail of the bitmap, and in general, the higher the resolution, the more pixels it contains, and the clearer the image.

Pixel and resolution are two important concepts that are inseparable, and their combination determines the amount of data in the image. For example, a 1-inch * 1-inch image with a resolution of 300ppi, the image contains 300*300=90000 pixels.

Basic concepts of bitmaps, vector graphics, pixels, and resolution