linux - How to convert a photo to a black and white image by ImageMagick?

How can I convert a JPEG photo to black and white (not grayscale) image like output of a FAX scanner, by ImageMagick?

Answer

According to this forum post:

However, if you want two colors only (black and white), then you need to threshold. For example, to select the color where above will be white and below will be black.

convert -threshold xx%

where xx is in range 0-100 (for percent).