{
    "mode": "man",
    "parameter": "pamunlookup",
    "section": "1",
    "url": "https://www.chedong.com/phpMan.php/man/pamunlookup/1/json",
    "generated": "2026-08-09T17:33:12Z",
    "synopsis": "pamunlookup -lookupfile=lookupfile inputfile\nAll  options can be abbreviated to their shortest unique prefix.  You may use two hyphens in‐\nstead of one.  You may separate an option name and its value with white space instead  of  an\nequals sign.",
    "sections": {
        "NAME": {
            "content": "pamunlookup - inverse of pamlookup\n\n",
            "subsections": []
        },
        "SYNOPSIS": {
            "content": "pamunlookup -lookupfile=lookupfile inputfile\n\nAll  options can be abbreviated to their shortest unique prefix.  You may use two hyphens in‐\nstead of one.  You may separate an option name and its value with white space instead  of  an\nequals sign.\n\n",
            "subsections": []
        },
        "DESCRIPTION": {
            "content": "This program is part of Netpbm(1).\n\npamunlookup  is  best described as the inverse of pamlookup (without -byplane).  For example,\nthe following normally yields output identical to the input:\n\n$ cat input.ppm | \\\npamunlookup -lookupfile=map.pam | \\\npamlookup -lookupfile=map.pam \\\n> output.ppm\n\n\nSpecifically, pamunlookup takes an input image and produces an output image of the same width\nand height in which each tuple is a single number.  That number  is  the  index  in  a  given\nlookup table of the tuple value that is in the same position in the input image.\n\nYou specify the lookup table the same way as for \u001b]8;;pamlookup.html#lookupimage\u001b\\pamlookup\u001b]8;;\u001b\\ .\n\nWhere a tuple in the input image is not in the lookup table, the number pamunlookup places in\nthe  output  index  image is one greater than the highest index in the lookup table.  Accord‐\ningly, the maxval of the output index image is the size of the lookup table.\n\n\n",
            "subsections": [
                {
                    "name": "Example",
                    "content": "Here is an example of pamunlookup's function.\n\nConsider an input image consisting of a 3x2 PPM as follows:\n\nred     yellow   red\nbeige   beige    beige\n\nand a lookup table consisting of a 3x1 PPM image as follows:\n\nred   yellow   beige\n\nThe lookup table above says Index 0 corresponds to the color red, Index 1 corresponds to yel‐\nlow, and Index 2 corresponds to beige.  The output of pamunlookup is the following index  im‐\nage:\n\n0   1   0\n2   2   2\n\n"
                },
                {
                    "name": "Miscellaneous",
                    "content": "The  inputfile  argument  identifies the file containing the index PAM or PNM image.  - means\nStandard Input.  It won't work if both the input image file and lookup table file  are  Stan‐\ndard Input.\n\nThe output index image goes to Standard Output.\n\n\n"
                }
            ]
        },
        "OPTIONS": {
            "content": "In  addition  to  the options common to all programs based on libnetpbm (most notably -quiet,\nsee \u001b]8;;index.html#commonoptions\u001b\\ Common Options\u001b]8;;\u001b\\ ), pamunlookup recognizes the following command line option:\n\n\n",
            "subsections": [
                {
                    "name": "-lookupfile=_",
                    "content": "lookupfile names the file that contains the PAM or PNM image that is the lookup table.\nThis option is mandatory.\n\n\n\n\n"
                }
            ]
        },
        "SEE ALSO": {
            "content": "pamlookup(1), ppmchange(1), pnmcolormap(1), pnm(1), pam(1)\n\n\n",
            "subsections": []
        },
        "HISTORY": {
            "content": "pamunlookup was new in Netpbm 10.72 (September 2015).\n",
            "subsections": []
        },
        "DOCUMENT SOURCE": {
            "content": "This manual page was generated by the Netpbm tool 'makeman' from  HTML  source.   The  master\ndocumentation is at\n\nhttp://netpbm.sourceforge.net/doc/pamunlookup.html\n\nnetpbm documentation                       09 August 2015                 Pamunlookup User Manual(1)",
            "subsections": []
        }
    },
    "summary": "pamunlookup - inverse of pamlookup",
    "flags": [
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "lookupfile names the file that contains the PAM or PNM image that is the lookup table. This option is mandatory."
        }
    ],
    "examples": [],
    "see_also": [
        {
            "name": "pamlookup",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/pamlookup/1/json"
        },
        {
            "name": "ppmchange",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/ppmchange/1/json"
        },
        {
            "name": "pnmcolormap",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/pnmcolormap/1/json"
        },
        {
            "name": "pnm",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/pnm/1/json"
        },
        {
            "name": "pam",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/pam/1/json"
        }
    ],
    "tldr": {
        "source": "not_found",
        "examples": []
    }
}