1Pnminvert User Manual(0) Pnminvert User Manual(0)
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6 pnminvert - invert a PNM image
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10 pnminvert
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12 [pnmfile]
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16 This program is part of Netpbm(1).
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18 pnminvert reads a PNM image as input, inverts it black for white, and
19 produces a PNM image as output.
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21 If the image is grayscale, pnminvert replaces a pixel with one of com‐
22 plementary brightness, i.e. if the original pixel has gamma-adjusted
23 gray value G, the output pixel has gray value maxval - G.
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25 If the image is color, pnminvert inverts each individual RGB component
26 the same as for a grayscale image.
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30 pnm(1)
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34 Copyright (C) 1989 by Jef Poskanzer.
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38netpbm documentation 08 August 1989 Pnminvert User Manual(0)