Feature Description
Connection points are homologous image points that can construct 3D models or establish connection relationships between adjacent models (images). Generating connection points helps improve accuracy during geometric correction, ensuring the spatial consistency of the imagery.
SuperMap iDesktopX supports this feature starting from version 11i(2023).
Parameter Description
| Parameter Name | Parameter Interpretation | Parameter Type |
| Dataset |
Displays the dataset containing the imagery used for generating connection points. It is not editable. |
DatasetMosaic |
| Input Image Type | Select the type of imagery used for generating connection points. The default is Panchromatic Image. It can also be switched to Multispectral Image, Forward-looking Image, Rear-view Image, or Front View and Rear View Image based on the specific situation. | ComboBoxImageType |
| Refer to the Adjustment File |
Based on existing adjustment file information, make the newly generated connection points approximate the accuracy of the existing ones. Use the Add and Delete buttons in the toolbar to conveniently manage multiple reference adjustment files. The reference adjustment file is obtained from the Block Network Adjustment function. |
ReferenceFileData |
| Error Threshold |
The error threshold for gross error elimination during image matching. The value range is [0,40]. The default is 5, and the unit is px. During the image matching process, the least squares method is used to fit the result points, removing points greater than the error threshold. A larger threshold retains more connection points but increases the probability of retaining erroneous points. |
Double |
| Point Distribution Mode |
Select the connection point distribution mode. Two methods are provided: Conventional and Uniform. The default is Conventional.
|
PointDistributionMethod |
| Number of Blocks in Column Direction |
Available when Conventional is selected in Point Distribution Mode. The number of blocks into which each overlapping area is divided in the column direction. The default value is 4. |
Integer |
| Number of Blocks in Row Direction |
Available when Conventional is selected in Point Distribution Mode. The number of blocks into which each overlapping area is divided in the row direction. The default value is 4. |
Integer |
| Matching Method |
Available when Conventional is selected in Point Distribution Mode. Six matching methods are provided, and one can be selected based on data characteristics and requirements. Among them, the AFHORP and RIFT methods support multimodal data matching; CASP and DEEPFT are based on deep learning and require additional configuration of AI models and installation of the CUDA environment. In general, it is recommended to use MOTIF, CASP, or DEEPFT.
|
ImageMatchMethod |
| Maximum Per Block |
Available when Conventional is selected in Point Distribution Mode. The maximum number of points retained within each image block during image matching. The value range is [1,2048]. The default is 256. |
Integer |
| Number of Seed Points |
Available when Uniform is selected in Point Distribution Mode. Sets the number of seed points for homologous point matching on each image scene. The value range is [64,6400]. The default is 512. When the image texture is poor, it is recommended to increase the number of connection points to match enough points and improve subsequent imagery quality. |
Integer |
| Seed Point Search |
Available when Uniform is selected in Point Distribution Mode. Sets the method for searching seed points. The default is Raster Center Point.
|
SearchSeedPointMethod |
| Template Size |
Available when Uniform is selected in Point Distribution Mode. Sets the interval size between seed points. The value range is [1,256]. The default is 40, and the unit is px. A larger template makes the searched points more reliable but takes longer. |
Integer |
| Search Radius |
Available when Uniform is selected in Point Distribution Mode. Sets the search radius for seed points during image matching. The value range is [0,256]. The default value is 40, and the unit is px. A larger search radius increases the matching range and also the processing time. |
Double |
| Semantic Culling of Non-ground Points | Not selected by default. When selected, connection points within cloud areas and building areas can be automatically culled based on AI semantic technology. | Boolean |
| Cloud Area | Available after selecting Semantic Culling of Non-ground Points. Selected by default, meaning connection points within cloud areas will be automatically culled based on the set dataset. If not selected, connection points within cloud areas will be retained. The dataset must contain an ImageName field, and the name must correspond to the image currently to be processed. | Boolean |
| Dataset |
Displayed after Cloud Area is selected. It is not editable. For workflows related to DOM production, use the cloud amount data from Set the Image Path. For workflows related to DSM production, use the cloud amount data from Set Image Path (dsm/dem). |
DatasetVector |
| Building Area |
Available after selecting Semantic Culling of Non-ground Points. Selected by default, meaning building areas will be automatically identified and connection points within those areas will be culled. If not selected, connection points within building areas will be retained. |
Boolean |
Output Result
A TiePoint vector point dataset is generated in the Control Point datasource.
Related Topics
Generate Ground Control Points
References
[1] Chen, P., Yu, L., Wan, Y., Pei, Y., Liu, X., Yao, Y., ... & Zhang, Y. (2025). CasP: Improving Semi-Dense Feature Matching Pipeline Leveraging Cascaded Correspondence Priors for Guidance. In Proceedings of the IEEE/CVF International Conference on Computer Vision (pp. 28063-28072).