dectris.albula.DImage Class Reference

The Dectris Image class. More...

Public Member Functions
def	DImage (dataType="int32")
	Default constructor. More...
def	DImage (width, height, dataType="int32")
	Construct image of given size More...
def	DImage (width, height, value)
	Construct image of given size filled with a specific value. More...
def	DImage (image, dataType=None)
	Construct DImage from existing DImage or numpy array More...
def	DImage (image, value)
	Construct image from an existing DImage but set all pixels to value. More...
def	resize (width, height)
	Resize image. More...
def	dataType ()
	Data type string. More...
def	width ()
	Width of the image: Number of pixels in X. More...
def	height ()
	Height of the image: Number of pixels in Y. More...
def	data ()
	NumPy array keeping a copy of the image data. More...
def	fromData (numpyArray)
	Sets the image data from a numpy array. More...
def	pixel (iX, iY)
	Returns the pixel value at iX,iY. More...
def	pixel (iX, iY, defaultReturn)
	Returns the pixel value at iX,iY. More...
def	setPixel (x, y, value)
	Sets the pixel value at (x,y) More...
def	optionalData ()
	optionalData() returns a reference to a DImageOptionalData object containing header information of the image. More...
def	setOptionalData (optionalData)
	set the DImageOptionalData object containing the header data More...
def	mean (rect=None, mask=None, lowerCountLimit=- 1e30, upperCountLimit=1e30)
	Calculate the mean pixel value of the image given a mask, a rectangle, a lower and an upper count limit. More...
def	variance (rect=None, mask=None, lowerCountLimit=- 1e30, upperCountLimit=1e30)
	Calculate the variance of the image given a mask, a rectangle, a lower and an upper count limit. More...
def	rms (rect=None, mask=None, lowerCountLimit=- 1e30, upperCountLimit=1e30)
	Calculate the rms pixel value of the image given a mask, a rectangle, a lower and an upper count limit. More...
def	median (rect=None, mask=None)
	Calculate the median pixel value of the image providing a mask image. More...
def	lowCut (cutValue)
	Replace all pixels with counts less than cutValue with cutValue. More...
def	lowCut (img)
	Replace all pixels with counts less than the pixel value of img with the pixel value of img. More...
def	highCut (cutValue)
	Replace all pixels with counts greater than cutValue with cutValue. More...
def	highCut (img)
	Replace all pixels with counts greater than the pixel value of img with the pixel value of img More...
def	numberOfPixelsInInterval (lowerLimit, upperLimit, rect=None, mask=None)
	Calculate the number of pixels with values below, above and inside the interval [lowerLimit,uppperLimit]. More...
def	fill (value, rect=None, mask=None)
	Fill pixels of the image providing a mask image. More...
def	extract (rect)
	Extrakt a region of the image to a new image. More...
def	createMask (lowerLimit, upperLimit, inverse=False)
	Creates a mask from an image. More...
def	splineFit (nGridX, nOrderX, nGridY, nOrderY, skipNModuleBorderPix, mask=None)
	Fit a 2 dimensional spline to the image. More...
def	medianFilter (m, n, mask=None)
	Apply median filter to image providing a mask file. More...
def	meanFilter (m, n, mask=None)
	Apply mean filter to image providing a mask file. More...
def	varianceFilter (m, n, mask=None)
	Apply variance filter to image providing a mask file. More...

Detailed Description

The Dectris Image class.

Slicing or indexing operator.

Class DImage provides functionality to manipulate detector images.

class DImage provides the following operations:

-DImage	Unary minus operator of an image
DImage += img	The += operator for an image
DImage -= img	The -= operator for an image
DImage *= img	The *= operator for an image
DImage /= img	The /= operator for an image
DImage += value	The += operator for a value
DImage -= value	The -= operator for a value
DImage *= value	The *= operator for a value
DImage /= value	The /= operator for a value
DImage + img	The + operator for an image
DImage - img	The - operator for an image
DImage * img	The * operator for an image
DImage + value	The + operator for a value
DImage - value	The - operator for a value
DImage * value	The * operator for a value
DImage[ position ]	DImage supports indexing and slicing. img[x,y] returns the pixel value at (x,y), img[x:x+width,y:y+height] returns the subimage at (x,y) of the given width and height. In addition a third slicing parameter denotes the step size of the subimage, e.g. img[x0:x1:xstep,y0:y1:xstep] returns a subimage where in the x direction (y direction) every xstep'th (ystep'th) pixel is taken into account. If optionalData() has a pixel mask the returned image has a pixel mask as well (see DImageOptionalData.pixel_mask()). The indexing operation can be used to set pixel values. E.g. img[0:100,100:200] = value sets pixels between [0,100) and [100:200) to value, where value may be either a numeric value or a DImage object. If value is a DImage its dimensions must coincide with the dimensions of the replaced region, else DRuntimeException is thrown. If slicing parameters are outside image border DOutOfRangeException is thrown. Parameters position Tuple of two integers or slicing objects, or one DRect object. Returns DImage or numeric value. Pixel masks of returned images are set if optionalData() has a pixel mask

Constructor & Destructor Documentation

DImage() [1/5]

def dectris.albula.DImage.DImage

(

dataType = "int32"

)

Default constructor.

Construct empty DImage of the type defined by dataType.

Parameters

dataType

String defining the data type: "int8", "int16", "int32", "int64", "uint8", "uint16", "uint32", "uint64", "float32", "float64"

DImage() [2/5]

def dectris.albula.DImage.DImage	(		width,
			height,
			dataType = "int32"
	)

Construct image of given size

Parameters

width
height
dataType	String defining the data type: "int8", "int16", "int32", "int64", "uint8", "uint16", "uint32", "uint64", "float32", "float64"

DImage() [3/5]

def dectris.albula.DImage.DImage	(		width,
			height,
			value
	)

Construct image of given size filled with a specific value.

The type of value must be Integer or Float resulting in a "int32" or "float32" image.

Parameters

width	Width of the image
height	Height of the image
value	Integer or Float. This value defines the image datatype and will be assigned to all pixels

DImage() [4/5]

def dectris.albula.DImage.DImage	(		image,
			dataType = None
	)

Construct DImage from existing DImage or numpy array

Parameters

image	DImage or 2-dimensional numpy array of type int, uint of float.
dataType	Either None or one of the following: "int8", "int16", "int32", "int64", "uint8", "uint16", "uint32", "uint64", "float32", "float64". If dataType is None the type of the new image is the same as image.

DImage() [5/5]

def dectris.albula.DImage.DImage	(		image,
			value
	)

Construct image from an existing DImage but set all pixels to value.

The shape of the constructed image is taken from image but the data type and the pixels values are taken from value. The type of value must be Integer or Float resulting in a "int32" or "float32" image.

Parameters

image	DImage whose shape defines the shape of constructed image
value	Integer or Float. This value defines the image datatype and will be assigned to all pixels

Member Function Documentation

createMask()

def dectris.albula.DImage.createMask	(		lowerLimit,
			upperLimit,
			inverse = False
	)

Creates a mask from an image.

Pixels within [lowerLimit, upperLimit] will be unmasked (i.e set to 0). If inverse flag is true, pixels within [lowerLimit, upperLimit] will be masked (i.e. set to 1). Unmasked pixels get the value 0, masked pixels get the value 1.

Parameters

lowerLimit	Integer or Float
upperLimit	Integer or Float
inverse	Bool

Returns

mask image. DImage of type "uint32"

data()

def dectris.albula.DImage.data

(

)

NumPy array keeping a copy of the image data.

The returned array is a two dimensional array in row major order. Hence the row (y-position) is accessed by the first index and the column (x-position) by the second index. Note: This is different to pixel() and setPixel().
Note: Starting from version 3.0 data() contains a copy to the image data rather than a reference. Hence it is no longer possible to change the image data by data(). Use fromData() instead.

Returns

NumPy array linked to the data

dataType()

def dectris.albula.DImage.dataType

(

)

Data type string.

Returns

One of the strings: "int8", "int16", "int32", "int64", "uint8", "uint16", "uint32", "uint64", "float32", "float64"

extract()

def dectris.albula.DImage.extract

(

rect

)

Extrakt a region of the image to a new image.

Parameters

rect	DRect object. Subregion to take into account

fill()

def dectris.albula.DImage.fill	(		value,
			rect = None,
			mask = None
	)

Fill pixels of the image providing a mask image.

Parameters

value	Integer or Float, which is casted to the image type
rect	DRect object. If not None, subregion to take into account.
mask	DImage object. If not None, do not take into account pixels masked with values different from zero

fromData()

def dectris.albula.DImage.fromData

(

numpyArray

)

Sets the image data from a numpy array.

numpyArray will be casted to the data type of the image.

Parameters

numpyArray

2-dimensional numpy array of type int, uint of float.

Returns

Reference to the DImage itself

height()

def dectris.albula.DImage.height

(

)

Height of the image: Number of pixels in Y.

highCut() [1/2]

def dectris.albula.DImage.highCut

(

cutValue

)

Replace all pixels with counts greater than cutValue with cutValue.

Parameters

cutValue

Float or Integer

highCut() [2/2]

def dectris.albula.DImage.highCut

(

img

)

Replace all pixels with counts greater than the pixel value of img with the pixel value of img

Parameters

img

DImage

lowCut() [1/2]

def dectris.albula.DImage.lowCut

(

cutValue

)

Replace all pixels with counts less than cutValue with cutValue.

Parameters

cutValue

FLoat, Integer or DImage

lowCut() [2/2]

def dectris.albula.DImage.lowCut

(

img

)

Replace all pixels with counts less than the pixel value of img with the pixel value of img.

Parameters

img

DImage

mean()

def dectris.albula.DImage.mean	(		rect = None,
			mask = None,
			lowerCountLimit = - 1e30,
			upperCountLimit = 1e30
	)

Calculate the mean pixel value of the image given a mask, a rectangle, a lower and an upper count limit.

Parameters

rect	DRect object. If not None, subregion to take into account
mask	DImage object. If not None, do not take into account pixels masked with values different from zero
lowerCountLimit
upperCountLimit

meanFilter()

def dectris.albula.DImage.meanFilter	(		m,
			n,
			mask = None
	)

Apply mean filter to image providing a mask file.

Every pixel is set to the mean of a square of size m*n around the pixel. Eventually throws an DException.

Parameters

m	width of the filter region. Must to be odd.
n	height of the filter region. Must to be odd.
mask	DImage object. If not None, do not take into account pixels masked with values different from zero

Returns

image with filter applied

median()

def dectris.albula.DImage.median	(		rect = None,
			mask = None
	)

Calculate the median pixel value of the image providing a mask image.

Parameters

rect	DRect object. If not None, subregion to take into account
mask	DImage object. If not None, do not take into account pixels masked with values different from zero

Returns

median value

medianFilter()

def dectris.albula.DImage.medianFilter	(		m,
			n,
			mask = None
	)

Apply median filter to image providing a mask file.

Every pixel is set to the median of a square of size m*n around the pixel. Eventually throws an DException.

Parameters

m	width of the filter region. Must to be odd.
n	height of the filter region. Must to be odd.
mask	DImage object. If not None, do not take into account pixels masked with values different from zero

Returns

image with filter applied

numberOfPixelsInInterval()

def dectris.albula.DImage.numberOfPixelsInInterval	(		lowerLimit,
			upperLimit,
			rect = None,
			mask = None
	)

Calculate the number of pixels with values below, above and inside the interval [lowerLimit,uppperLimit].

Parameters

lowerLimit	lower limit of the interval
upperLimit	upper limit ot the interval
rect	DRect object. If not None, subregion to take into account
mask	DImage object. If not None, do not take into account pixels masked with values different from zero

Returns

tuple (below, inside, above) i.e. (# pixels with value < lowerLimit, # pixels with lowerLimit <= value <= upperLimit, # pixels with value > upperLimit )

optionalData()

def dectris.albula.DImage.optionalData

(

)

optionalData() returns a reference to a DImageOptionalData object containing header information of the image.

The returned reference must not live longer than the parent DImage object. Changes applied to the returned object apply to the images optional data as well, because it is a reference.

Returns

Reference to a DImageOptionalData object containing header information of the image

pixel() [1/2]

def dectris.albula.DImage.pixel	(		iX,
			iY
	)

Returns the pixel value at iX,iY.

If iX,iY is outside the image borders 0 is returned.

Parameters

iX	x position
iY	y position

pixel() [2/2]

def dectris.albula.DImage.pixel	(		iX,
			iY,
			defaultReturn
	)

Returns the pixel value at iX,iY.

If iX,iY is outside the image borders defaultReturn is returned.

Parameters

iX	x position
iY	y position
defaultReturn

resize()

def dectris.albula.DImage.resize	(		width,
			height
	)

Resize image.

All data is destroyed.

Parameters

width	New image width
height	New image height

rms()

def dectris.albula.DImage.rms	(		rect = None,
			mask = None,
			lowerCountLimit = - 1e30,
			upperCountLimit = 1e30
	)

Calculate the rms pixel value of the image given a mask, a rectangle, a lower and an upper count limit.

Parameters

rect	DRect object. If not None, subregion to take into account
mask	DImage object. If not None, do not take into account pixels masked with values different from zero
lowerCountLimit
upperCountLimit

setOptionalData()

def dectris.albula.DImage.setOptionalData

(

optionalData

)

set the DImageOptionalData object containing the header data

Parameters

optionalData

DImageOptionalData object

setPixel()

def dectris.albula.DImage.setPixel	(		x,
			y,
			value
	)

Sets the pixel value at (x,y)

Parameters

x	Integer value denoting the x position
y	Integer value denoting the y position
value	Integer or Float

splineFit()

def dectris.albula.DImage.splineFit	(		nGridX,
			nOrderX,
			nGridY,
			nOrderY,
			skipNModuleBorderPix,
			mask = None
	)

Fit a 2 dimensional spline to the image.

Parameters

nGridX
nOrderX
nGridY
nOrderY
skipNModuleBorderPix
mask	DImage object. If not None, do not take into account pixels masked with values different from zero

variance()

def dectris.albula.DImage.variance	(		rect = None,
			mask = None,
			lowerCountLimit = - 1e30,
			upperCountLimit = 1e30
	)

Calculate the variance of the image given a mask, a rectangle, a lower and an upper count limit.

Parameters

rect	DRect object. If not None, subregion to take into account
mask	DImage object. If not None, do not take into account pixels masked with values different from zero
lowerCountLimit
upperCountLimit

Returns

mean

varianceFilter()

def dectris.albula.DImage.varianceFilter	(		m,
			n,
			mask = None
	)

Apply variance filter to image providing a mask file.

Every pixel is set to the variance of a square of size m*n around the pixel. Eventually throws an DException.

Parameters

m	width of the filter region. Must to be odd.
n	height of the filter region. Must to be odd.
mask	DImage object. If not None, do not take into account pixels masked with values different from zero

Returns

image with filter applied

width()

def dectris.albula.DImage.width

(

)

Width of the image: Number of pixels in X.