GOM Inspect Python API documentation

Welcome to the GOM Inspect Python API documentation. Here you can find a detailed documentation of a subset of the Add-on programming specification. Please bear in mind, that recording commands with the script editor can be used to add new functions to your script.

Important

The now preliminary API is currently under heavy development and will change massively in the near future.

Image processing

Image related functions can be used to query images from the measurements of a project. This is not done directly, but via an ‘image acquisition’ object which acts as a proxy between the image storing data structured and the functions which can be used to process the image data.

Terminology:

‘point’: 3D coordinate in the project.
‘pixel’: 2D coordinate in an image.

gom.api.project

gom.api.project.get_image_aquisition(measurement, camera, stages)

Generate a list of image acquisition objects which can be used as input for image processing functions.

API version:

1

Parameters:

measurement (Reference) – Measurement the image is to be queried from
camera (str) –
Identifier for the camera which contributed to the measurement. Valid values are:
- ’left camera’: Left camera in a two camera system or the only existing camera in a single camera system
- ’right camera’: Right camera in a two camera system
- ’photogrammetry’: Photogrammery (TRITOP) camera
stages (list [int]) – (Optional) Indices of the stages for which an image acquisition object is to be generated.

Returns:

List of image acquisition objects which can be used by image processing functions. The number of objects matches the number of stage indices in the stages parameter of the function call.

Return type:

List [Reference]

Example

measurement = gom.app.project.measurement_series['Deformation series'].measurements['D1']
stage = gom.app.project.stages['Stage 1']
point = gom.app.project.actual_elements['Point 1'].coordinate
 
left = gom.api.project.get_image_acquisition (measurement, 'left camera', [stage.index])[0]
right = gom.api.project.get_image_acquisition (measurement, 'right camera', [stage.index])[0]

gom.api.imaging

gom.api.imaging.compute_pixels_from_point(point_and_image_acquisition)

Compute pixel coordinates from point coordinates

API version:: 1
Parameters:: point_and_image_acquisition (List) – List of pairs where each entry describes a point coordinate plus the image acquisition object which should be used to compute the matching image pixel.
Returns:: List of image pixels where each entry is the result of projecting the point via the associated image acquisition structure into the image. The pixel coordinate system center is located in the upper left corner.
Return type:: List

Example

measurement = gom.app.project.measurement_series['Deformation series'].measurements['D1']
stage = gom.app.project.stages['Stage 1']
point = gom.app.project.actual_elements['Point 1'].coordinate
 
left = gom.api.project.get_image_acquisition (measurement, 'left camera', [stage.index])[0]
right = gom.api.project.get_image_acquisition (measurement, 'right camera', [stage.index])[0]
 
p = gom.api.imaging.compute_pixels_from_point ([(point, left), (point, right)])
 
print (p)

[gom.Vec2d (1031.582008690226, 1232.4155555222544), gom.Vec2d (1139.886626169376, 1217.975608783256)]

gom.api.imaging.compute_point_from_pixels([[pixel_and_image acquisition, ]]use_calibration)

Compute point coordinate from pixel coordinates

API version:

1

Parameters:

pixel_and_image_acquisition (List) – List of pairs where each entry describes a pixel image coordinate plus the image acquisition object which should be used to compute the matching point.
use_calibration (bool) – If set, the information from the calibration is used to compute the point. Project must provide a calibration for that case.

Returns:

List of lists of (pixel, residuum) where each entry is the result of projecting the point via the associated image acquisition structure into the image. The pixel coordinate system center is located in the upper left corner.

Return type:

List

measurement = gom.app.project.measurement_series['Deformation 1'].measurements['D1']
stage = gom.app.project.stages[0]
point = gom.app.project.actual_elements['Start Point 1'].coordinate
 
left = gom.api.project.get_image_acquisition (measurement, 'left camera', [stage.index])[0]
 
p = gom.api.imaging.compute_point_from_pixels ([[(gom.Vec2d (10, 10), left)]], False)
 
print (p)

[[gom.Vec3d (-638.2453100625158, 1627.6169782583584, 0.0), 0.0]]

gom.api.imaging.compute_epipolar_line(image_acquisition_1, [pixel_and_image_acquisition]_2, max_distance)

Compute epipolar line coordinates

API version:

1

Parameters:

image_aquisition_1 (List) – Handle of the image acquisition the epipolar line should be found in.
pixel_and_image_aquisition_2 (List) – List of pairs where each entry describes a pixel image coordinate plus the image acquisition object which should be used to compute the matching point. The image acquisition object here. is the “other” acquisition providing the pixels used to find the matching epipolar lines in the image_acquisition_1 object.
max_distance (double) – Maximum search distance in mm.

Returns:

List of epipolar line coordinates, each one consisting of a list of image pixels.

Return type:

List

stage = gom.app.project.stages['Stage 1']
point = gom.app.project.actual_elements['Point 1'].coordinate
 
left = gom.api.project.get_image_acquisition (measurement, 'left camera', [stage.index])[0]
right = gom.api.project.get_image_acquisition (measurement, 'right camera', [stage.index])[0]
 
l = gom.api.imaging.compute_epipolar_line (left, [(gom.Vec2d (1617, 819), right)], 10.0)
 
print (l)

[[gom.Vec2d (4.752311764226988, 813.7915394509045), gom.Vec2d (10.749371580282741, 813.748887458453), gom.Vec2d (16.73347976996274, 813.706352662515), ...]]

Checks

Functions used to handle checks.

gom.api.scripted_checks_util

gom.api.scripted_checks_util.is_scalar_checkable(element)

Test if the referenced element is suitable for inspection with a scalar check.

API version:: 1
Parameters:: element (Reference) – Element to be checked
Returns:: True’ if the given element s suitable for inspection with a scalar check.
Return type:: bool

element = gom.app.project.inspection['Point 1']
state = gom.api.scripted_checks_util.is_scalar_checkable (element)
print (state)

True

gom.api.scripted_checks_util.is_surface_checkable(element)

Test if the referenced element is suitable for inspection with a surface check.

API version:: 1
Parameters:: element (Reference) – Element to be checked
Returns:: True’ if the given element s suitable for inspection with a surface check.
Return type:: bool

element = gom.app.project.inspection['Point 1']
state = gom.api.scripted_checks_util.is_surface_checkable (element)
print (state)

True

gom.api.scripted_checks_util.is_curve_checkable(element)

Test if the referenced element is suitable for inspection with a curve check.

API version:: 1
Parameters:: element (Reference) – Element to be checked
Returns:: True’ if the given element s suitable for inspection with a curve check.
Return type:: bool

element = gom.app.project.inspection['Point 1']
state = gom.api.scripted_checks_util.is_curve_checkable (element)
print (state)

True