gray_histo_abs
— Calculate the gray value distribution.
gray_histo_abs(Regions, Image : : Quantization : AbsoluteHisto)
The operator gray_histo_abs
calculates for the image
(Image
) within Regions
the absolute
(AbsoluteHisto
) ) histogram of the gray values.
The parameter Quantization
defines, how many frequencies of
neighbored gray values are added for one frequency value. The resulting
histogram AbsoluteHisto
is a tuple, whose indices are mapped on the
gray values of the input image Image
and whose elements contain the
frequencies of the gray values. The indices i of the frequency value
are calculated from the gray values g and the quantization q as follows:
whereas MIN denotes the minimal gray value, e.g., -128 for an int1
image type. Therefore, the size of the tuple results from the ratio of the
full domain of gray values and the quantization, e.g., for images of
int2 in .
The origin gray value of the signed image types int1 resp. int2 is
mapped on the index 128 resp. 32768, negative resp. positive gray values
have smaller resp. greater indices.
Note that the operator gray_histo_abs
only considers
the given Regions
and ignores any previously set domain
of the input image Image
.
Regions
(input_object) region(-array) →
object
Region in which the histogram is to be calculated.
Image
(input_object) singlechannelimage →
object (byte / cyclic / direction / int1 / int2 / uint2)
Image the gray value distribution of which is to be calculated.
Quantization
(input_control) number →
(real / integer)
Quantization of the gray values.
Default value: 1.0
Suggested values: 1.0, 2.0, 3.0, 5.0, 10.0
Restriction: Quantization >= 1.0
AbsoluteHisto
(output_control) histogram-array →
(integer)
Absolute frequencies of the gray values.
The operator gray_histo_abs
returns the value TRUE if the image
has defined gray values and the parameters are correct. The
behavior in case of empty input (no input images available) is set
via the operator
set_system(::'no_object_result',<Result>:)
, the behavior
in case of empty region is set via
set_system(::'empty_region_result',<Result>:)
.
If necessary an exception is raised.
histo_to_thresh
,
gen_region_histo
min_max_gray
,
intensity
,
gray_histo
,
gray_histo_range
disp_image
,
histo_2dim
,
scale_image_max
,
entropy_gray
Foundation