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diff --git a/doc/tools/thumbnail.rst b/doc/tools/thumbnail.rst new file mode 100644 index 00000000..722388d0 --- /dev/null +++ b/doc/tools/thumbnail.rst @@ -0,0 +1,66 @@ +thumbnail +========= + +.. program:: thumbnail + +Synopsis +-------- + +**thumbnail** [ *options* ] *input.tif* *output.tif* + +Description +----------- + +:program:`thumbnail` is a program written to show how one might use the +``SubIFD`` tag (#330) to store thumbnail images. +:program:`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 +------- + +.. option:: -w width + + Specify the width of thumbnail images in pixels. + +.. option:: -h height + + Specify the height of thumbnail images in pixels. + +.. option:: -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 +-------- + +:doc:`tiffdump` (1), +:doc:`tiffgt` (1), +:doc:`tiffinfo` (1), +:doc:`/man/libtiff` (3tiff), |