Image Types

Most of the digital image channels have 256 intensity levels coded on 8 bits per channel. The color image is produced by combining three channels. The grayscale images have only one channel with 256 gray levels per pixel. The binary images are coded on 1 bit and therefore have only 2 levels.

Binary image

A binary image has only one channel (Binary). Pixel values in binary images are either black or white. The binary images can be created by one of the segmentation methods.

 Note: The color of the objects (white regions) is referred to as the foreground color. The rest (black) is referred to as the background color.

Grayscale image

A grayscale image has only one channel (Gray levels). Pixel values in grayscale images are based upon luminance.

The Real Gray channel results from the conversion of a color image to a grayscale image (in lens options or in channel operations). The coefficients used to compute luminance are 0.299 (red), 0.587 (green) and 0.114 (blue). Pixel = 0.299 * red + 0.587 *green + 0.114 *blue.

Color image

In lens options or in channel operations, a color image can be separated into three channels using the RGB or IHS color space or in one Real Gray channel (see above).

RGB

The RGB model is an additive color model and also one of the most common. It has three primary colors: red, green and blue. These three colors are combined in various proportions to produce all the colors displayed on your image. The ICC (International Color Consortium) profile used by JMicroVision is the sRGB.

IHS

IHS (or called HSV) is a more intuitive color space than RGB.

• Intensity (or luminosity) is the amount of light independently of the color.
• Hue describes the visual sensation according to which an area appears to be similar to one of the perceived colors, red, yellow, green and blue, or a combination of two of them.
• Saturation is the colorfulness of an area judged in proportion to its brightness. Saturation runs from neutral gray through pastel to saturated colors. A vivid color usually has a high saturation level (not much white).