Fill NoData by Bilinear Interpolation
Overview
Bilinear interpolation fills NoData cells by estimating values from surrounding valid cells. It is suitable for repairing small gaps in continuous raster surfaces. Different interpolation methods vary in smoothness, local-extreme preservation, and edge behavior.
Use Cases
- Fill small NoData holes in continuous raster data such as elevation, temperature, or imagery bands.
- Prepare spatially continuous raster input for later zonal statistics, threshold extraction, or map production.
- Repair gaps before visualization or downstream analysis.
Parameters
| Parameter | Description | Notes |
|---|---|---|
| Input raster file | Raster file whose NoData cells need bilinear interpolation | Required |
| Output raster file | Output raster file after bilinear interpolation | Required |
Steps
- Start the tool: Open Geoprocessing Toolbox → Spatial Analysis Tools > Raster Synthesis > Fill NoData, then start the Fill NoData by Bilinear Interpolation tool pane.
- Prepare input: Select the Input raster file and confirm that the data is complete and readable.
- Set core parameters: Confirm that the NoData areas to be filled are appropriate for bilinear interpolation.
- Set output: Specify the Output raster file and confirm that the output path, format, and naming rules meet downstream requirements.
- Run and inspect the result: Click Run, then check whether filled cells, value range, and spatial position meet expectations.
Notes
- Interpolation is best for small or moderate NoData gaps. Large gaps may produce unreliable surfaces.
- Use a projected coordinate system for distance-sensitive interpolation when possible.
- Sparse valid cells, uneven distribution, or outliers can reduce the reliability of the filled surface.