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void gwy_data_field_grains_mark_curvature (GwyDataField *data_field
,GwyDataField *grain_field
,gdouble threshval
,gboolean below
);
Marks data that are above/below curvature threshold.
data_field |
Data to be used for marking. |
|
grain_field |
Data field to store the resulting mask to. |
|
threshval |
Relative curvature threshold, in percents. |
|
below |
If |
void gwy_data_field_grains_mark_watershed (GwyDataField *data_field
,GwyDataField *grain_field
,gint locate_steps
,gint locate_thresh
,gdouble locate_dropsize
,gint wshed_steps
,gdouble wshed_dropsize
,gboolean prefilter
,gboolean below
);
Performs watershed algorithm.
data_field |
Data to be used for marking. |
|
grain_field |
Result of marking (mask). |
|
locate_steps |
Locating algorithm steps. |
|
locate_thresh |
Locating algorithm threshold. |
|
locate_dropsize |
Locating drop size. |
|
wshed_steps |
Watershed steps. |
|
wshed_dropsize |
Watershed drop size. |
|
prefilter |
Use prefiltering. |
|
below |
If |
gboolean gwy_data_field_grains_remove_grain (GwyDataField *grain_field
,gint col
,gint row
);
Removes one grain at given position.
gboolean gwy_data_field_grains_extract_grain (GwyDataField *grain_field
,gint col
,gint row
);
Removes all grains except that one at given position.
If there is no grain at (col
, row
), all grains are removed.
void gwy_data_field_grains_remove_by_number (GwyDataField *grain_field
,gint number
);
Removes grain identified by number
.
grain_field |
Field of marked grains (mask). |
|
number |
Grain number was filled by |
Since: 2.35
void gwy_data_field_grains_remove_by_size (GwyDataField *grain_field
,gint size
);
Removes all grains below specified area.
void gwy_data_field_grains_remove_by_height (GwyDataField *data_field
,GwyDataField *grain_field
,gdouble threshval
,gboolean below
);
Removes grains that are higher/lower than given threshold value.
data_field |
Data to be used for marking |
|
grain_field |
Field of marked grains (mask) |
|
threshval |
Relative height threshold, in percents. |
|
below |
If |
void
gwy_data_field_grains_remove_touching_border
(GwyDataField *grain_field
);
Removes all grains that touch field borders.
Since: 2.30
GwyComputationState * gwy_data_field_grains_watershed_init (GwyDataField *data_field
,GwyDataField *grain_field
,gint locate_steps
,gint locate_thresh
,gdouble locate_dropsize
,gint wshed_steps
,gdouble wshed_dropsize
,gboolean prefilter
,gboolean below
);
Initializes the watershed algorithm.
This iterator reports its state as GwyWatershedStateType.
data_field |
Data to be used for marking. |
|
grain_field |
Result of marking (mask). |
|
locate_steps |
Locating algorithm steps. |
|
locate_thresh |
Locating algorithm threshold. |
|
locate_dropsize |
Locating drop size. |
|
wshed_steps |
Watershed steps. |
|
wshed_dropsize |
Watershed drop size. |
|
prefilter |
Use prefiltering. |
|
below |
If |
void
gwy_data_field_grains_watershed_iteration
(GwyComputationState *state
);
Performs one iteration of the watershed algorithm.
Fields state
and progress fraction
of watershed state are updated
(fraction is calculated for each phase individually). Once state
becomes GWY_WATERSHED_STATE_FINISHED
, the calculation is finised.
A watershed iterator can be created with
gwy_data_field_grains_watershed_init()
. When iteration ends, either
by finishing or being aborted, gwy_data_field_grains_watershed_finalize()
must be called to release allocated resources.
void
gwy_data_field_grains_watershed_finalize
(GwyComputationState *state
);
Destroys a watershed iterator, freeing all resources.
void gwy_data_field_grains_mark_height (GwyDataField *data_field
,GwyDataField *grain_field
,gdouble threshval
,gboolean below
);
Marks data that are above/below height threshold.
data_field |
Data to be used for marking. |
|
grain_field |
Data field to store the resulting mask to. |
|
threshval |
Relative height threshold, in percents. |
|
below |
If |
void gwy_data_field_grains_mark_slope (GwyDataField *data_field
,GwyDataField *grain_field
,gdouble threshval
,gboolean below
);
Marks data that are above/below slope threshold.
data_field |
Data to be used for marking. |
|
grain_field |
Data field to store the resulting mask to. |
|
threshval |
Relative slope threshold, in percents. |
|
below |
If |
gdouble
gwy_data_field_otsu_threshold (GwyDataField *data_field
);
Finds Otsu's height threshold for a data field.
The Otsu's threshold is optimal in the sense that it minimises the inter-class variances of two classes of pixels: above and below theshold.
Since: 2.37
void gwy_data_field_grains_add (GwyDataField *grain_field
,GwyDataField *add_field
);
Adds add_field
grains to grain_field
.
Note: This function is equivalent to
gwy_data_field_max_of_fields(grain_field, grain_field, add_field);
and it will be probably removed someday.
void gwy_data_field_grains_intersect (GwyDataField *grain_field
,GwyDataField *intersect_field
);
Performs intersection betweet two grain fields,
result is stored in grain_field
.
Note: This function is equivalent to
gwy_data_field_min_of_fields(grain_field, grain_field, intersect_field);
and it will be probably removed someday.
gint gwy_data_field_number_grains (GwyDataField *mask_field
,gint *grains
);
Numbers grains in a mask data field.
mask_field |
Data field containing positive values in grains, nonpositive in free space. |
|
grains |
Zero-filled array of integers of equal size to |
gint gwy_data_field_number_grains_periodic (GwyDataField *mask_field
,gint *grains
);
Numbers grains in a periodic mask data field.
This function differs from gwy_data_field_number_grains()
by the assumption
of periodicity, i.e. grains can touch across the opposite field edges.
mask_field |
Data field containing positive values in grains, nonpositive in free space. |
|
grains |
Zero-filled array of integers of equal size to |
Since: 2.38
gint * gwy_data_field_get_grain_bounding_boxes (GwyDataField *mask_field
,gint ngrains
,const gint *grains
,gint *bboxes
);
Find bounding boxes of all grains.
mask_field |
Data field containing positive values in grains, nonpositive
in free space. However its contents is ignored as all
grain information is taken from |
|
ngrains |
The number of grains as returned by
|
|
grains |
Grain numbers filled with |
|
bboxes |
Array of size at least 4*( |
Since: 2.3
GwyDataLine * gwy_data_field_grains_get_distribution (GwyDataField *data_field
,GwyDataField *grain_field
,GwyDataLine *distribution
,gint ngrains
,const gint *grains
,GwyGrainQuantity quantity
,gint nstats
);
Computes distribution of requested grain characteristics.
Puts number of grains vs. grain value data into distribution
, units, scales
and offsets of distribution
are updated accordingly.
Note the i
-th bin is [i
*dx
+off
,(i
+1)*dx
+off
] so the central value
you probably want to use for plotting is (i
+0.5)*dx
+off
(where dx
is
the distribution
data line pixel size, off
is its offset).
data_field |
Data field used for marking. For some quantities its values are not used, but units and physical dimensions are always taken from it. |
|
grain_field |
Data field (mask) of marked grains. Note if you pass
non- |
|
distribution |
Data line to store grain distribution to. |
|
ngrains |
The number of grains as returned by
|
|
grains |
Grain numbers filled with |
|
quantity |
The quantity to calculate. |
|
nstats |
The number of samples to take on the distribution function. If nonpositive, a suitable resolution is determined automatically. |
A data line with the distribution: distribution
itself if it was
not NULL
, otherwise a newly created GwyDataLine caller must
destroy. If there are no grains, NULL
is returned and
distribution
is not changed.
gdouble * gwy_data_field_grains_get_values (GwyDataField *data_field
,gdouble *values
,gint ngrains
,const gint *grains
,GwyGrainQuantity quantity
);
Calculates characteristics of grains.
This is a bit low-level function, see also
gwy_data_field_grains_get_distribution()
.
The array values
will be filled with the requested grain value for each
individual grain (0th item of values
which does not correspond to any grain
will be overwritten with an arbitrary value and should be ignored).
The grain numbers serve as indices in values
. Therefore as long as the
same grains
is used, the same position in values
corresponds to the same
particular grain. This enables one for instance to calculate grain sizes
and grain heights and then correlate them.
data_field |
Data field used for marking. For some quantities its values
are not used, but its dimensions determine the dimensions of
|
|
values |
Array of size |
|
ngrains |
The number of grains as returned by
|
|
grains |
Grain numbers filled with |
|
quantity |
The quantity to calculate. |
values
itself if it was not NULL
, otherwise a newly allocated
array that caller has to free.
gdouble ** gwy_data_field_grains_get_quantities (GwyDataField *data_field
,gdouble **values
,const GwyGrainQuantity *quantities
,guint nquantities
,guint ngrains
,const gint *grains
);
Calculates multiple characteristics of grains simultaneously.
See gwy_data_field_grains_get_values()
for some discussion. This function
is more efficient if several grain quantities need to be calculated since
gwy_data_field_grains_get_values()
can do lot of repeated work in such case.
data_field |
Data field used for marking. For some quantities its values
are not used, but its dimensions determine the dimensions of
|
|
values |
Array of |
|
quantities |
Array of |
|
nquantities |
The number of requested different grain values. |
|
ngrains |
The number of grains as returned by
|
|
grains |
Grain numbers filled with |
values
itself if it was not NULL
, otherwise a newly allocated
array that caller has to free with g_free()
, including the
contained arrays.
Since: 2.22
gboolean
gwy_grain_quantity_needs_same_units (GwyGrainQuantity quantity
);
Tests whether a grain quantity is defined only when lateral and value units match.
TRUE
if quantity
is meaningless when lateral and value units
differ, FALSE
if it is always defined.
Since: 2.7
GwySIUnit * gwy_grain_quantity_get_units (GwyGrainQuantity quantity
,GwySIUnit *siunitxy
,GwySIUnit *siunitz
,GwySIUnit *result
);
Calculates the units of a grain quantity.
quantity |
A grain quantity. |
|
siunitxy |
Lateral SI unit of data. |
|
siunitz |
Value SI unit of data. |
|
result |
An SI unit to set to the units of |
When result
is NULL
, a newly creates SI unit that has to be
dereferenced when no longer used later. Otherwise result
itself
is simply returned, its reference count is NOT increased.
Since: 2.7
void gwy_data_field_area_grains_tgnd (GwyDataField *data_field
,GwyDataLine *target_line
,gint col
,gint row
,gint width
,gint height
,gboolean below
,gint nstats
);
Calculates threshold grain number distribution.
This function is a simple gwy_data_field_area_grains_tgnd_range()
that
calculates the distribution in the full range.
data_field |
A data field. |
|
target_line |
A data line to store the distribution to. It will be resampled to the requested width. |
|
col |
Upper-left column coordinate. |
|
row |
Upper-left row coordinate. |
|
width |
Area width (number of columns). |
|
height |
Area height (number of rows). |
|
below |
If |
|
nstats |
The number of samples to take on the distribution function. If nonpositive, a suitable resolution is determined automatically. |
void gwy_data_field_area_grains_tgnd_range (GwyDataField *data_field
,GwyDataLine *target_line
,gint col
,gint row
,gint width
,gint height
,gdouble min
,gdouble max
,gboolean below
,gint nstats
);
Calculates threshold grain number distribution in given height range.
This is the number of grains for each of nstats
equidistant height
threshold levels. For large nstats
this function is much faster than the
equivalent number of gwy_data_field_grains_mark_height()
calls.
data_field |
A data field. |
|
target_line |
A data line to store the distribution to. It will be resampled to the requested width. |
|
col |
Upper-left column coordinate. |
|
row |
Upper-left row coordinate. |
|
width |
Area width (number of columns). |
|
height |
Area height (number of rows). |
|
min |
Minimum threshold value. |
|
max |
Maximum threshold value. |
|
below |
If |
|
nstats |
The number of samples to take on the distribution function. If nonpositive, a suitable resolution is determined automatically. |
void gwy_data_field_grains_splash_water (GwyDataField *data_field
,GwyDataField *minima
,gint locate_steps
,gdouble locate_dropsize
);
void
gwy_data_field_grain_distance_transform
(GwyDataField *data_field
);
Performs Euclidean distance transform of a data field with grains.
Each non-zero value will be replaced with Euclidean distance to the grain boundary, measured in pixels.
See also gwy_data_field_grain_simple_dist_trans()
for simple distance
transforms such as city-block or chessboard.
Since: 2.36
void gwy_data_field_grain_simple_dist_trans (GwyDataField *data_field
,GwyDistanceTransformType dtype
,gboolean from_border
);
Performs a simple distance transform of a data field with grains.
Each non-zero value will be replaced with a distance to the grain boundary, measured in pixels.
See also gwy_data_field_grain_distance_transform()
for Euclidean distance
transform.
data_field |
A data field with zeroes in empty space and nonzeroes in grains. |
|
dtype |
Type of simple distance to use. |
|
from_border |
|
Since: 2.41
gboolean gwy_data_field_fill_voids (GwyDataField *data_field
,gboolean nonsimple
);
Fills voids in grains in a data field representing a mask.
Voids in grains are zero pixels in data_field
from which no path exists
through other zero pixels to the field boundary. The paths are considered
in 8-connectivity because grains themselves are considered in
4-connectivity.
Since: 2.37
gint gwy_data_field_waterpour (GwyDataField *data_field
,GwyDataField *result
,gint *grains
);
Performs the classical Vincent watershed segmentation of a data field.
The segmentation always results in the entire field being masked with the exception of thin (8-connectivity) lines separating the segments (grains).
Compared to gwy_data_field_grains_mark_watershed()
, this algorithm is very
fast. However, when used alone, it typically results in a serious
oversegmentation as each local minimum gives raise to a grain. Furthermore,
the full segmentation means that also pixels which would be considered
outside any grain in the topographical sense will be assigned to some
catchment basin. Therefore, pre- or postprocessing is usually necessary,
using the gradient image or a more sophisticated method.
The function does not assign pixels with value HUGE_VAL
or larger to any
segment. This can be used to pre-mark certain areas explicitly as
boundaries.
Since the algorithm numbers the grains as a side effect, you can pass a
grains
array and get the grain numbers immediatelly, avoiding the
relatively (although not drastically) expensive
gwy_data_field_number_grains()
call.
data_field |
A data field to segmentate. |
|
result |
Data field that will be filled with the resulting mask. It will be
resized to the dimensions of |
|
grains |
Optionally, an array with the same number of items as |
The number of segments (grains) in the result, excluding the
separators, i.e. the same convention as in
gwy_data_field_number_grains()
is used.
Since: 2.37
void gwy_data_field_mark_extrema (GwyDataField *dfield
,GwyDataField *extrema
,gboolean maxima
);