{
    "content": [
        {
            "type": "text",
            "text": "# pnmhistmap(1) (man)\n\n**Summary:** pnmhistmap - draw a histogram for a PGM or PPM file\n\n**Synopsis:** pnmhistmap [-black] [-white] [-max N] [-verbose] [pnmfile]\n\n## Flags\n\n| Flag | Long | Arg | Description |\n|------|------|-----|-------------|\n| — | — | — |  |\n| — | — | — | The -black and -white options, which can be used seperately or together, are useful for im‐ ages with a large percentage |\n| — | — | — | ful for inputs with a large percentage of single-color pixels which are not black or white. |\n| — | — | — | Report the progress of making the histogram, including the largest-count value used to scale the output. All flags can b |\n\n## See Also\n\n- pgmhist(1)\n- ppmhist(1)\n- pgm(5)\n- ppm(5)\n\n## Section Outline\n\n- **NAME** (2 lines)\n- **SYNOPSIS** (2 lines)\n- **DESCRIPTION** (7 lines)\n- **OPTIONS** (1 lines) — 4 subsections\n  - -black (1 lines)\n  - -white (6 lines)\n  - -max (3 lines)\n  - -verbose (5 lines)\n- **BUGS** (7 lines)\n- **SEE ALSO** (2 lines)\n- **AUTHOR** (5 lines)\n\n## Full Content\n\n### NAME\n\npnmhistmap - draw a histogram for a PGM or PPM file\n\n### SYNOPSIS\n\npnmhistmap [-black] [-white] [-max N] [-verbose] [pnmfile]\n\n### DESCRIPTION\n\nReads  a  portable anymap as input, although bitmap (PBM) input produces an error message and\nno image.  Produces an image showing a histogram of the color (or gray) values in the  input.\nA  graymap (PGM) input produces a bitmap output.  A pixmap (PPM) input produces pixmap output\nwith three overlaid histograms: a red one for the red input, a green one for the green input,\nand  a blue one for the blue input.  The output is fixed in size: 256 pixels wide by 200 pix‐\nels high.\n\n### OPTIONS\n\n#### -black\n\n#### -white\n\nThe -black and -white options, which can be used seperately or together, are useful  for  im‐\nages  with  a  large percentage of pixels whose value is zero or 255, which can cause the re‐\nmaining histogram data to become unreadbaly small.  Note that, for pixmap inputs,  these  op‐\ntions apply to all colors; if, for example, the input has a large number of bright-red areas,\nyou will probably want to use the -white option.\n\n#### -max\n\nful  for  inputs with a large percentage of single-color pixels which are not black or\nwhite.\n\n#### -verbose\n\nReport the progress of making the histogram, including the largest-count value used to\nscale the output.\n\nAll flags can be abbreviated to their shortest unique prefix.\n\n### BUGS\n\nAssumes  maxval  is  always  255.  Images with a smaller maxval will only use the lower-value\nside of the histogram.  This can be overcome either by piping  the  input  through  \"pnmdepth\n255\"  or by cutting and scaling the lower-value side of the histogram.  Neither is a particu‐\nlarly elegant solution.\n\nShould allow the output size to be specified.\n\n### SEE ALSO\n\npgmhist(1), ppmhist(1), pgm(5), ppm(5)\n\n### AUTHOR\n\nWilson H. Bent. Jr. (whb@usc.edu).\n\n\n\n25 October 1993                             pnmhistmap(1)\n\n"
        }
    ],
    "structuredContent": {
        "command": "pnmhistmap",
        "section": "1",
        "mode": "man",
        "summary": "pnmhistmap - draw a histogram for a PGM or PPM file",
        "synopsis": "pnmhistmap [-black] [-white] [-max N] [-verbose] [pnmfile]",
        "flags": [
            {
                "flag": "",
                "long": null,
                "arg": null,
                "description": ""
            },
            {
                "flag": "",
                "long": null,
                "arg": null,
                "description": "The -black and -white options, which can be used seperately or together, are useful for im‐ ages with a large percentage of pixels whose value is zero or 255, which can cause the re‐ maining histogram data to become unreadbaly small. Note that, for pixmap inputs, these op‐ tions apply to all colors; if, for example, the input has a large number of bright-red areas, you will probably want to use the -white option."
            },
            {
                "flag": "",
                "long": null,
                "arg": null,
                "description": "ful for inputs with a large percentage of single-color pixels which are not black or white."
            },
            {
                "flag": "",
                "long": null,
                "arg": null,
                "description": "Report the progress of making the histogram, including the largest-count value used to scale the output. All flags can be abbreviated to their shortest unique prefix."
            }
        ],
        "examples": [],
        "see_also": [
            {
                "name": "pgmhist",
                "section": "1",
                "url": "https://www.chedong.com/phpMan.php/man/pgmhist/1/json"
            },
            {
                "name": "ppmhist",
                "section": "1",
                "url": "https://www.chedong.com/phpMan.php/man/ppmhist/1/json"
            },
            {
                "name": "pgm",
                "section": "5",
                "url": "https://www.chedong.com/phpMan.php/man/pgm/5/json"
            },
            {
                "name": "ppm",
                "section": "5",
                "url": "https://www.chedong.com/phpMan.php/man/ppm/5/json"
            }
        ],
        "section_outline": [
            {
                "name": "NAME",
                "lines": 2,
                "subsections": []
            },
            {
                "name": "SYNOPSIS",
                "lines": 2,
                "subsections": []
            },
            {
                "name": "DESCRIPTION",
                "lines": 7,
                "subsections": []
            },
            {
                "name": "OPTIONS",
                "lines": 1,
                "subsections": [
                    {
                        "name": "-black",
                        "lines": 1
                    },
                    {
                        "name": "-white",
                        "lines": 6
                    },
                    {
                        "name": "-max",
                        "lines": 3
                    },
                    {
                        "name": "-verbose",
                        "lines": 5
                    }
                ]
            },
            {
                "name": "BUGS",
                "lines": 7,
                "subsections": []
            },
            {
                "name": "SEE ALSO",
                "lines": 2,
                "subsections": []
            },
            {
                "name": "AUTHOR",
                "lines": 5,
                "subsections": []
            }
        ]
    }
}