Trim a landsat image to a latitude-longitude box. This is only an approximate operation, because landsat images are provided in x-y coordinates, not longitude-latitude coordinates.
landsatTrim(x, ll, ur, box, debug = getOption("oceDebug"))A landsat object, e.g. as read by read.landsat.
A list containing longitude and latitude, for the
lower-left corner of the portion of the image to retain, or a vector
with first element longitude and second element latitude. If provided,
then ur must also be provided, but box cannot.
A list containing longitude and latitude, for the
upper-right corner of the portion of the image to retain, or a vector
with first element longitude and second element latitude. If provided,
then ll must also be provided, but box cannot.
A list containing x and y (each of length 2),
corresponding to the values for ll and ur, such as would
be produced by a call to locator(2). If provided, neither
ll nor ur may be provided.
A flag that turns on debugging. Set to 1 to get a moderate amount of debugging information, or a higher value for more debugging.
An object of landsat-class, with data having
been trimmed approximately as specified.
As of June 25, 2015, the matrices storing the image data are trimmed to indices
determined by linear interpolation based on the location of the ll and
ur corners within the lon-lat corners specified in the image data. (A
previous version trimmed in UTM space, and in fact this may be done in future
also, if a problem in lonlat/utm conversion is resolved.) An error results if
there is no intersection between the trimming box and the image box.
The documentation for landsat-class explains the
structure of landsat objects, and also outlines the other functions dealing
with them.
Other things related to landsat data: [[,landsat-method,
[[<-,landsat-method,
landsat-class, landsatAdd,
landsat, plot,landsat-method,
read.landsat,
summary,landsat-method