Multispectral and Panchromatic Registration

Feature Description

Multispectral and panchromatic registration uses the panchromatic image as a reference to register the multispectral image to ensure the quality of image fusion.

SuperMap iDesktopX11i(2023) starts to support this function.

Parameter description

Parameter Name Parameter interpretation Parameter type
Dataset

Displays the original multispectral image data used for registration, and it is not editable.

DatasetMosaic
Use ortho panchromatic data Checked by default, the result data from Generate Orthophoto will be used as the reference data. If unchecked, the panchromatic data from the original image will be used as the reference data. Boolean
Panchromatic data

Available after checking Use ortho panchromatic data.

Displays the dataset containing the panchromatic image data after orthorectification, and it is not editable.

DatasetMosaic
Matching method

Six matching methods are provided, and can be selected based on data characteristics and requirements. Among them, the AFHORP and RIFT methods support multi-modal data matching; CASP and DEEPFT are based on deep learning and require additional AI model configuration and CUDA environment installation; generally, MOTIF, CASP, or DEEPFT are recommended.

  • MOTIF (default): A template matching algorithm for multi-modal images, characterized by the use of lightweight feature descriptors. MOTIF can overcome nonlinear radiation distortion caused by differences between SAR and optical images.
  • CASP: A novel cascade matching flow, which benefits from integrating high-level features, helping to reduce the computational cost of low-level feature extraction. This flow decomposes the matching stage into two progressive stages, first establishing one-to-many correspondences on a coarser scale as cascade priors. Then, using these priors for guidance, one-to-one matches are determined on the target scale.[1]
  • DEEPFT: An image matching method based on deep learning.
  • SIFT: A method for extracting distinctive invariant features from images, which can be used for reliable matching between objects or scenes from different viewpoints.
  • RIFT: A feature matching algorithm robust to large-scale nonlinear radiation distortion. It can improve the stability of feature detection and overcome the limitations of feature description based on gradient information.
  • AFHORP: A feature matching algorithm for multi-modal images. AFHORP has strong resistance to radiation distortion and contrast differences in multi-modal images and performs excellently in solving problems of orientation reversal and abrupt phase extremum changes.
 
Correction model

Provides Linear RPC Correction Model, Quadratic Polynomial RPC Correction Model, and Cubic Polynomial RPC Correction Model. Linear RPC Correction Model is selected by default.

  • Linear RPC Correction Model: Suitable for cases where internal distortion of the image is small. This model requires no less than 4 ground control points. Please add control point information via the Manage Ground Control Points function.
  • Quadratic Polynomial RPC Correction Model: Suitable for cases where internal distortion of the image is moderate. This model requires no less than 9 ground control points. Please add control point information via the Manage Ground Control Points function.
  • Cubic Polynomial RPC Correction Model: Suitable for cases where internal distortion of the image is large. This model requires no less than 16 ground control points. Please add control point information via the Manage Ground Control Points function.

If executing the production workflow, the Correction model parameter in Block Network Adjustment will be used, and it is not editable.

CorrectedModelType
Number of blocks in column direction The number of blocks dividing a scene of image in the column direction. The default is 12. Integer
Number of blocks in row direction The number of blocks dividing a scene of image in the row direction. The default is 4. Integer
Minimum points per block The minimum number of matched points within each image block. The default is 1000. Integer
Cloud mask Sets the data source where the cloud mask dataset is located. DataSource
Dataset Automatically removes tie points within the dataset bounds based on the set cloud mask dataset. By default, no cloud mask dataset is set, meaning all tie points are retained. DatasetVector
Building detection Not checked by default, meaning building area detection is not performed. When checked, building area detection will be automatically performed, and all tie points within the detected result range will be removed. Boolean
Export directory Uses the Processing path parameter in Set the Image Path, and it is not editable. File
Resolution type

Specifies the method for setting the output resulting image resolution. Original resolution is selected by default.

  • Original resolution: Retains the original resolution of the input image.
  • Fixed Value: Uses the input fixed value as the output image resolution.
  • Custom: Outputs different resolutions based on different satellite sensor types. After selecting the Custom option, the Custom Resolution: dialog box will pop up. You can click the Add button on the toolbar to add a record. Then click the cell in the Satellite sensor type column to select the sensor type. Finally, input the resolution corresponding to the sensor type in the cell of the Resolution column.
    Notes:
    • If the corresponding satellite sensor type is not found, please select the USEDEFINE option. After selecting this option, the system will use the resolution corresponding to USEDEFINE to output all data of unsupported satellite sensor types.
    • If processing image data of multiple satellite sensor types simultaneously (e.g., ZY3, GF-2, LandSat) but only set the resolution for one type (e.g., only set for ZY3), images of other satellite sensor types (e.g., GF-2 and LandSat) will be output using their original resolution.

If executing the production workflow, the Resolution type parameter in Generate Orthophoto will be used. When the resolution type in Generate Orthophoto is Fixed Value or Custom, the value here will be automatically calculated as 4 times.

OrthoRatioType
Coordinate system settings Uses the Output coordinate system parameter in Set the Image Path, and it is not editable. PrjCoordSys
Output format Uses the Output format parameter in Set the Image Path, and it is not editable. FileType
Compression method Uses the Compression method parameter in Set the Image Path, and it is not editable. CompressMethod

Output Result

  • Outputs the multispectral image data processed by orthorectification to the local folder.
  • Automatically creates an OrthoMuxmosaic dataset in the OrthoData data source based on the multispectral orthophoto image data.
  • Outputs the registration report RegistrationReport.csv file to the Adjustment/Registration directory.
    • If the process is executed multiple times, the Registration folder name will be suffixed with "_n".
    • In the registration report, one image pair is one record.
    • The registration report includes: serial number, multispectral image, panchromatic image, number of points, minimum mean error (pixel), maximum mean error (pixel), overall root-mean-square error (rmse) (pixel).

Related Topics

Block Network Adjustment

Generate Orthophoto

Image Fusion