1.1.1.0 image.boundingbox

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image.boundingbox - Function

1.1.1 Get the bounding box of the specified region
Description

This function finds the bounding box of a region of interest when it is applied to a particular image. It is returned in a record which has fields ‘blc’, ‘trc’, ‘inc’, ‘bbShape’, ‘regionShape’, ‘imageShape’, ‘blcf’ and ‘trcf’ containing the bottom-left corner, the top-right corner (in absolute image pixel coordinates), the increment (stride) of the region, the shape of the boundingbox, the shape of the region, the shape of the image, the blc in formatted absolute world coordinates and the trc in formatted absolute world coordinates, respectively.

Note that the shape of the bounding box will be different from the shape of the region if a non-unit stride (increment) is involved (see the example below).

Arguments


Inputs
region	The region of interest. Default is whole image.
	allowed:	any
	Default:	record

Returns
anyrecord

Example

"""
#
print "\t----\t boundingbox Ex 1 \t----"
ia.maketestimage() # Create image tool
x=[’3pix’,’6pix’,’9pix’,’6pix’,’5pix’,’5pix’,’3pix’] # X vector in abs pixels
y=[’3pix’,’4pix’,’7pix’,’9pix’,’7pix’,’5pix’,’5pix’] # Y vector in abs pixels
mycs = ia.coordsys()
r1=rg.wpolygon(x=x,y=y,csys=mycs.torecord()) # Create polygonal world region
mycs.done()
bb = ia.boundingbox(r1) # Find bounding box
print bb
#{’regionShape’: array([7, 7]), ’trc’: array([9, 9]),
# ’imageShape’: array([113, 76]),
# ’blcf’: ’00:00:27.733, -00.06.48.000’,
# ’trcf’: ’00:00:24.533, -00.05.36.000’, ’bbShape’: array([7, 7]),
# ’blc’: array([3, 3]), ’inc’: array([1, 1])}
ia.close()
#
"""

Example

"""
#
print "\t----\t boundingbox Ex 2 \t----"
ia.maketestimage()
b = rg.box([10,10],[20,20],[2,3])
print ia.boundingbox(b)
#{’regionShape’: array([6, 4]), ’trc’: array([20, 19]),
# ’imageShape’: array([113, 76]),
# ’blcf’: ’00:00:24.000, -00.05.24.000’,
# ’trcf’: ’00:00:18.667, -00.03.36.000’, ’bbShape’: array([11, 10]),
# ’blc’: array([10, 10]), ’inc’: array([2, 3])}

ia.close()
#
"""

In this example we see the difference between bbShape and regionShape because of the increment (stride). See also that the trc is modified by the increment.

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