This function is a wrapper of
magick::image_crop. While the
latter asks you to set a geometry
parameter, this function enables you
to set the four sides of a subregion only
by click the mouse. You must click at
least 2 times (that is, click on 2 different
points to define a rectangle). After clicking,
please press Esc on your keyboard. You
can also designate an irregular polygon
by mouse with at least 3 clicks. If it is
irregular, you MUST click on positions
in order (something like that, when you
draw a polygon in R, you must input
the positions of points in order).
image_crop_click(x, only_value = FALSE, rectangle = TRUE, trim = FALSE)an image read into R by
magick::image_read or an image
modified by functions in the magick
package.
the default is FALSE, which will return the subregion. If you set it to TRUE, the result is only four values with the order: left, right, top, bottom.
whether the cropped area is a rectangle (default is TRUE). If it is FALSE, the subregion can be irregular.
this is only used when
rectangle is FALSE. It decides whether
the irregular subregion is to be trimmed. If it
is FALSE (default), no trimming will be done.
If it is a 0 to 100 value,
magick::image_trim will be used, whose
fuzz argument is equal to trim.
If it is TRUE (not 1), trimming will be done
according to the mouse click you have made.