Feature Description

Batch reproject refers to simultaneously projecting multiple datasets under a data source. After conversion, the coordinates of the specified dataset are consistent with the coordinate system of the target datasource.

Feature Entry

• Start tab -> Data Processing group -> Project -> Batch Reproject.
• In the workspace manager, select the datasource's context menu and choose Batch Reproject.

Steps

1. List of source datasets：

   Import datasets that require batch reproject using the Add button. The list will display Source Dataset, Datasource, Coordinate System, and Target Dataset information.

2. Target Dataset：
   • Datasource: Click the drop-down button of the datasource combo box to select the datasource for saving the projection transformation result datasets.
   • Target coordinate system: Used to display detailed description information of the target datasource's coordinate system.
   • For the coordinate systems of the source datasource and target datasource, note the following points:
     • Planar coordinate systems do not support projection. In the dataset list on the right, datasets with planar coordinate systems in the source datasource are automatically filtered out. You can set a dataset's coordinate system on the "Coordinate System" page in its properties panel via right-click.
     • Generally, it is recommended that datasets in the source datasource maintain the same coordinate system as the source datasource. If a dataset in the source datasource has a different coordinate system, its actual coordinate system will be used as the source coordinate system during conversion.
     • For the target datasource, datasources with planar coordinate systems are automatically filtered out. You can set a datasource's coordinate system on the coordinate system page in its properties panel via right-click.
3. Reference System Conversion：
   • Conversion method: Click the drop-down button to the right of the "Conversion method" label. The dropdown menu lists over ten reference system conversion methods provided by the system, and you can select an appropriate one. For explanations of conversion methods, refer to Reference System Conversion Method Description.
   • Projection transformation parameters: Different conversion methods allow for different customizable parameters in the "Parameter Settings" dialog. For detailed descriptions of parameter settings, see Dataset Projection Conversion.
4. After completing all parameter settings, click the "Convert" button to perform the projection operation. You can view the projection transformation result in the output window.

Notes： All projections involve distortion, so transformations between different projections are often not fully reversible. That is, map data can be projected from its original system to another, but it may not always be precisely converted back. Therefore, users should save a copy of the original file before projection. Additionally, minimize the number of projection transformations to ensure accuracy of results. Each projection is designed to reduce distortion in specific areas for given characteristics, so they have applicable scopes. When performing projection transformations, transformations should occur between similar coordinate system ranges to maintain accuracy. For example, converting a world map from Mercator projection to Gauss projection ensures precision only near the central meridian, with significant distortion in distant areas. In practice, the choice of conversion method depends on specific circumstances. For determining parameters, purchase authoritative survey data or verify correctness using known control points in both coordinate systems. After text projection, the height and angle of text will be converted accordingly. If this change is undesired, reset the height and angle for the converted text.

Related Topics

Reproject Dataset

Transform Coordinates

Calculate Transformation Model Parameters