GETPIXEL

Section: User Commands (1)
Updated: July 2012
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NAME

getpixel - extract value of pixel (x,y) from a tiff.

SYNOPSIS

Extracts the hex-value of a given pixel from a .cam or .tiff file.
The pixel address may be in Hawaii-quadrants, Hawaii-fullframe, or X11-standard.

DESCRIPTION

getpixel: extract the numerical value of a single pixel from a .cam or .tiff file

USAGE:      getpixel -q QUAD -x X_POS -y Y_POS IMG_FILE
OPTIONS:    -q QUAD     is the quadrant number:  0,1,2,3, or F, or X11
             -x X_POS    is the x-co-ordinate, measured from the left. Range: [0, 511].
             -y Y_POS    is the y-co-ordinate, measured from the bottom. Range: [0, 511].

             -c, -r      are accepted as synonyms for -x, -y
             -h          shows help

IMG_FILE is either a .cam (.dat) or .tiff (.tif) file: either the cam or tiff
format will be selected, depending on the extension.

MODES:      QUADRANT    (-q 0,1,2,3):  x,y are the Hawaii-coordinates, within that quadrant
             FULL-FRAME  (-q F):        x,y are the Hawaii-coordinates, full-chip. Range: [0, 1023].
             X11-mode    (-q X11):      x,y are the X11-coordinates: full-frame, origin in top left.

See 'cam2tiff -h' for a diagram of the Hawaii chip, quadrants, and coordinate-axes.
Synonyms: x = column/fast-scan/pixel_clock; y = row/slow-scan/line_clock.
The output is a single 24-bit value, in the format 0xffeedd.

NOTE:  'stream' must be built with 32-bit quantum depth. This system has 32.
        To set this, build ImageMagick, configured --with-quantum-depth=32 .

AUTHOR

The author of getpixel and this manual page is Richard Neill, <cam2tiff#AT(spamblock)#richardneill.org>
Copyright July 2012; this is Free Software (GPL v3+), see the source for copying conditions.