# Interpolation

The Interpolation operator artificially increases the resolution of a raster by interpolating the values of the input raster. If the operator is queried with a resolution that is coarser than the input resolution, the interpolation is not applied but the input raster is returned unchanged. Unless a particular input resolution is specified, the resolution of the input raster is used, if it is known.

## Parameters

ParameterTypeDescriptionExample Value
interpolationInterpolationMethodthe interpolation method to be used"nearestNeighbor"
inputResolutionInputResolutionthe query resolution for the source operator"source"

## Types

The following describes the types used in the parameters.

### InterpolationMethod

The operator supports the following interpolation methods:

ValueDescription
nearestNeighborThe value of the nearest neighbor is used.
biLinearThe value is computed by bilinear interpolation.

### InputResolution

The operator supports the following input resolutions:

ValueDescription
{"type": "source"}The resolution of the input raster is used.
{"type": "value", "x": 0.1, "y": 0.1}The resolution is specified explicitly.

## Inputs

The Interpolation operator expects exactly one raster input.

ParameterType
sourceSingleRasterSource

## Errors

If the input resolution is set as "source" but the resolution of the input raster is not known, an error will be thrown.

## Example JSON

{
"type": "Raster",
"operator": {
"type": "Interpolation",
"params": {
"interpolation": "biLinear",
"inputResolution": {
"type": "source"
}
},
"sources": {
"raster": {
"type": "GdalSource",
"params": {
"data": {
"type": "internal",
"datasetId": "36574dc3-560a-4b09-9d22-d5945f2b8093"
}
}
}
}
}
}