pnmnorm

all

Normalize the contrast in a PNM image. See also: `pnmhisteq`.

Options (2)

boolean

Force the brightest pixels to be white, the darkest pixels to be black and spread out the ones in between quadratically such that pixels with a brightness of `n` become 50 % bright

Example: pnmnorm {{[-midv|-midvalue]}} {{n}} {{path/to/image.pnm}} > {{path/to/output.pnm}}

-kboolean

Keep the pixels' hue, only modify the brightness

Example: pnmnorm {{[-k|-keephues]}} {{path/to/image.pnm}} > {{path/to/output.pnm}}

Examples (4)

Force the brightest pixels to be white, the darkest pixels to be black and spread out the ones in between linearly

pnmnorm path/to/image.pnm > path/to/output.pnm

Force the brightest pixels to be white, the darkest pixels to be black and spread out the ones in between quadratically such that pixels with a brightness of `n` become 50 % bright

pnmnorm [-midv|-midvalue] n path/to/image.pnm > path/to/output.pnm

Keep the pixels' hue, only modify the brightness

pnmnorm [-k|-keephues] path/to/image.pnm > path/to/output.pnm

Specify a method to calculate a pixel's brightness

pnmnorm -luminosity|colorvalue|saturation path/to/image.pnm > path/to/output.pnm

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