Feature Description

Filter image refers to the process of automatically filtering and selecting original images based on rules such as image extent, acquisition time, resolution, cloud coverage, and duplicate names. Through this process, high-quality images that meet specific requirements can be quickly extracted from massive data, effectively reducing redundancy. This not only improves data processing speed but also ensures the accuracy and timeliness of analysis results, thereby meeting the needs of various application scenarios such as topographic mapping, resource surveys, environmental monitoring, and disaster assessment.

Filter image can quickly exclude data that does not meet the criteria, such as outdated, low-resolution, or heavily cloud-covered images, ensuring that subsequent analysis is based on high-quality data.

SuperMap ImageX Pro supports this feature starting from the 2025 version.

Function Entry

Imagery Tab -> Satellite Image Processing Group -> Filter Image.

Operation Instructions

1. Click the Imagery tab -> Image Management group -> Filter Image button to open the Filter Image panel and the Image Preview window.
2. In the Filter Image panel, set screening parameters such as Image Path, Filter Criteria, and Trim Overlapping Images. Detailed descriptions are as follows:
   • Image Path: Set the path where the original images are stored. The system will automatically read all image data under this path (including subfolders).
   • Filter Criteria: Filter original images based on the following conditions:
     • Image Extent: Provides three methods to set the extent, loading only images within the specified range:
       • Geographic Range: Construct the image extent using Left, Bottom, Right, and Top coordinates of a geographic coordinate system (GCS). Supports copying/pasting coordinates for reuse.
       • Range Data: Use the bounds of a specified dataset as the image extent. Supported formats include UDBX/UDB, GeoJson, or ShapeFile.
       • Standard View Frame Number: Enter the map sheet number under a designated scale, and the system will automatically calculate the image range based on the map sheet number.
     • Acquisition Time: Set the time range for image acquisition. The system automatically reads the time information from image files and only loads images within the specified time range.
     • Resolution (m): Set the resolution range for images. The system automatically reads the resolution from image files and only loads images within the specified resolution range.
     • Cloud Coverage (%): Set the cloud coverage range for images. The system automatically reads cloud coverage information from image files and only loads images within the specified cloud coverage range.
   • Trim Overlapping Images: After selecting images based on filter criteria, overlapping images may exist and require further elimination:
     • Eliminate Duplicate Names: Remove images with duplicate file names.
     • First Priority: Set the first priority for trimming overlapping images. Options include Time, Resolution, or Same Orbit.
     • Second Priority: Set the second priority for trimming overlapping images, choosing from the remaining two options. For example, if Time is selected as the first priority, only Resolution or Same Orbit can be selected here.
     • Third Priority: Set the third priority for trimming overlapping images, which will be the only remaining option. For example, if Time is the first priority and Resolution is the second, then only Same Orbit can be selected here.

     For example: Check Eliminate Duplicate Names, set First Priority to Time, Second Priority to Resolution, and Third Priority to Same Orbit. During image filtering, duplicate images will be removed first, then the most recent images (by time) will be retained, followed by images with the highest resolution, and finally images from the same orbit.

3. Click the Query button. The Search Result will list qualifying panchromatic and multispectral images in groups, and the Image Preview window will display the image bounds info. You can flexibly control whether an image is displayed in the Image Preview window by using the Visible button in front of each panchromatic or multispectral image.
4. Check if the filtering results meet the requirements via the Filter Image window. For images that do not meet the requirements or need replacement, you can use the tools in the Search Result groups to add or delete images. When deleting an image, you only need to delete the panchromatic or multispectral image; its paired image will be automatically deleted.
5. After confirming the filtering is complete, click the Export button on the toolbar to output an image files list to save the filtering results. In the Set the Image Path and Set Image Path (dsm/dem) sections for original and reference images, you can apply the filtering results to process production by using the Add List method.

Related Topics

DOM Production Workflow

DOM Tessellation Workflow

DSM/DEM Production Workflow

Setting Environment Variables