|
|
|
|
|
A bitmap represents an image as a mosaic of colored dots called pixels. The pixels are arranged in a fixed number of rows and columns. Bitmaps are also known as raster images, and the method used to create them is called rasterization.
When a bitmap is edited, the color values of its pixels are changed to form the new image.
The following color modes are supported:
Grayscale |
Pixels are colored in 256 shades of gray ranging from solid black to solid white. |
Black and White |
Each pixel is either black or white, with no shades of gray. |
RGB |
The color values for each pixel are expressed as a combination of red, green, and blue values. Up to 16.7 million different colors can be reproduced under this color model. |
Indexed |
The color of each pixel is indicated by a reference to a separate swatch table containing 256 colors. |
CMYK |
The color values for each pixel are expressed as a combination of cyan, magenta, yellow, and black values. This is the color mode most commonly used for color printing. |
If a bitmap is magnified or printed at too low a resolution, the individual pixels become visible. This gives the image a jagged, pixilated appearance (see above).
Resolution is the number of pixels displayed per unit of printed length in an image, usually measured in pixels per inch (PPI) or dots per inch (DPI).