-blankthreshold

-blankthreshold percentage

The -blankthreshold flag sets the percentage value of white pixels to dark or black pixels to determine if a page is blank.  The percentage is the percentage value to use.  The -blankthreshold flag is ignored if -noblankpages is not specified.

For example, if percentage is 99, this means that the page must consist of 99% "white" or blank pixels to be considered a blank page.  The lower the percentage value, the "darker" the page will be before being considered blank.

Example:

twainsave -filename test.tif -filetype tif1 -multipage -noblankpages -blankthreshold 98

This command acquires a multipage TIFF file that uses no compression to a TIFF file called test.tif.  If any blank pages are found, they are not saved to the TIFF file (the -noblankpages option does this).  To consider a page blank, there must be at least 98% white pixels on the page (the -blankthreshold setting).

Default Setting:

If -noblankpages is specified, and -blankthreshold is not specified, the threshold value is 98.