NAME

       thumbnail - create a TIFF file with thumbnail images

SYNOPSIS

       thumbnail [ options ] input.tif output.tif

DESCRIPTION

       thumbnail  is  a  program written to show how one might use the SubIFD tag (#330) to store
       thumbnail images.  thumbnail copies a TIFF Class F facsimile file to the output  file  and
       for each image an 8-bit greyscale "thumbnail sketch" is created.  The output file contains
       the thumbnail image with the associated full-resolution page linked below with the  SubIFD
       tag.

       By  default,  thumbnail  images  are  216  pixels  wide  by  274  pixels high.  Pixels are
       calculated by sampling and filtering the input image with each pixel value passed  through
       a contrast curve.

OPTIONS

       -w width
              Specify the width of thumbnail images in pixels.

       -h height
              Specify the height of thumbnail images in pixels.

       -c contrast
              Specify  a  contrast curve to apply in generating the thumbnail images.  By default
              pixels values are passed through a linear contrast curve that simply maps the pixel
              value ranges.  Alternative curves are:

                                       ┌───────┬────────────────────────┐
                                       │Curve  │ Description            │
                                       ├───────┼────────────────────────┤
                                       │exp50  │ 50% exponential curve  │
                                       ├───────┼────────────────────────┤
                                       │exp60  │ 60% exponential curve  │
                                       ├───────┼────────────────────────┤
                                       │exp70  │ 70% exponential curve  │
                                       ├───────┼────────────────────────┤
                                       │exp80  │ 80% exponential curve  │
                                       ├───────┼────────────────────────┤
                                       │exp90  │ 90% exponential curve  │
                                       ├───────┼────────────────────────┤
                                       │exp    │ pure exponential curve │
                                       ├───────┼────────────────────────┤
                                       │linear │ linear curve           │
                                       └───────┴────────────────────────┘

BUGS

       There are no options to control the format of the saved thumbnail images.

SEE ALSO

       tiffdump (1), tiffgt (1), tiffinfo (1), libtiff (3tiff),

AUTHOR

       LibTIFF contributors

COPYRIGHT

       1988-2023, LibTIFF contributors