bwshrink — shrink a black and white bw file
bwshrink
[-s squareinsize
] [-w in_width
] [-n in_height
] [-f shrink_factor
] [-u ] [infile.bw
] > outfile.bw
bwshrink
will take a black and white
bw(5)
format file of given dimensions and produce a smaller
scaled version.
The
-w
and
-n
flags specify the input file width and number of scan lines in pixels.
They can both be set to the same value via
-s.
Defaults of 512 are assumed for unspecified dimensions.
The integer scaling factor is set with the
-f
flag. By default, the factor is 2.
The program reads the entire image into memory, and then scales the image down to 1/factor the original size in both dimensions.
By default, bwshrink uses boxcar averaging to produce the output pixels from
the input. The
-u
option causes bwshrink to use image undersampling instead.
If the dimensions of the input image are not evenly divisible by the shrink factor, incorrect and bizarre output is generated.