1.1.1.0 image.pad

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image.pad - Function

1.1.1 Pad the perimeter of the direction plane with a number of pixels of specified value and mask.

Description

This method pads the directional plane of an image with a specified number of pixels on each side. The numerical and mask values of the padding pixels may also be specified. If a region is selected, a subimage of that region is created and then padded with the specified pixel parameters. Thus, padding an image of shape (ra, dec, freq) = (512, 512, 10) specifying npixels = 3 results in an image of size (518, 518, 10), with the blc of the directional plane of the original pixel set corresponding to the directional pixel of (3, 3) in the output. If wantreturn is True, an image analysis tool attached to the output image is returned. If False, none is returned.

Arguments


Inputs
outfile	Output image name. If not specified, no persistent image is created.
	allowed:	string
	Default:
npixels	Number of pixels with which to pad each side of the direction plane.
	allowed:	int
	Default:	1
value	Value given to the padding pixels.
	allowed:	double
	Default:	0
padmask	Value of the mask for the padding pixels. True=>good (unmasked), False=>bad (masked).
	allowed:	bool
	Default:	false
overwrite	Overwrite the output if it exists? Default False
	allowed:	bool
	Default:	false
region	Region selection. See ”help par.region” for details. Default is to use the full image.
	allowed:	any
	Default:	variant
box	Rectangular region to select in direction plane. See ”help par.box” for details. Default is to use the entire direction plane.
	allowed:	string
	Default:
chans	Channels to use. See ”help par.chans” for details. Default is to use all channels.
	allowed:	string
	Default:
stokes	Stokes planes to use. See ”help par.stokes” for details. Default is to use all stokes planes.
	allowed:	string
	Default:
mask	Mask to use. See help par.mask. Default is none.
	allowed:	string
	Default:
stretch	Stretch the mask if necessary and possible? See help par.stretch. Default False
	allowed:	bool
	Default:	false
wantreturn	Return an image analysis tool attached to the created subimage?
	allowed:	bool
	Default:	true

Returns
image

Example

        ia.fromshape("",[50, 50, 10])
        # pad it with 5 pixels of value 2.5 all unmasked
        padded = ia.pad(npixels=5, value=2.5, padmask=True)
        ia.done()
        # returns [60, 60, 10]
        paddedshape = padded.shape()
        padded.done()

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