Cached Raster function

Overview

The Cached Raster function creates a preprocessed cache at the point in the function chain where it's added. It is typically inserted in a function chain before the functions that can impede performance due to more computationally intensive processing. These functions can include Convolution, Band Arithmetic, Pansharpen, or Geometric. Multiple Arithmetic functions are also computationally intensive.

Notes

Caution:

This function is only supported when added to the function chain for an item in a mosaic dataset. It is not valid to add this function to the mosaic dataset's function chain or to the function chain on a layer.

You can insert this function when accessing the function chain for each raster in a mosaic dataset using the Raster Functions Batch Editor or the Define Mosaic Dataset Item Cache tool. You can generate the cache for each item when adding the function using the Define Mosaic Dataset Item Cache tool, or you can generate or update the cache using the Synchronize Mosaic Dataset tool with the Build Item Cache parameter checked.

Parameters

ParameterDescription

Raster

The location in the function chain representing the last function output used in this function. This will be populated automatically.

Cache Path

The location where the cached dataset will be stored. By default, the cache is generated and stored in a folder next to where the mosaic dataset resides. This folder has the same name as the geodatabase, with a .cache extension. However, if the mosaic dataset is created in an enterprise geodatabase, the cache will be created in that geodatabase.

Cache Filename

A system-generated name used to identify the cached dataset. This will appear once the function has been added to the function chain. It cannot be edited.

Compression

Specifies the type of compression, if any, that will be used when generating the cache.

  • Lossless—Lossless compression retains the value of each pixel when generating the cache dataset.
  • Lossy—Lossy compression does not retain the exact value of each pixel when generating the cached dataset. When using this method, a compression quality can also be set between 1 and 100 percent.
  • None—No compression will be used when generating the cached dataset.

The default is Lossless.

Maximum Allowed Columns

Limits the size of the cache dataset by number of pixels in columns. If the extent of the data cannot fit within this constraint, it will not be generated.

The default is 200000.

Maximum Allowed Rows

Limits the size of the cache dataset by number of pixels in rows. If the extent of the data cannot fit within this constraint, it will not be generated.

The default is 200000.

Request Size Type

Specifies the technique that will be used to resample the resolution of the cached raster. Resampling a cached raster can make complicated function chains and intensive processes perform faster.

  • Pixel Size Factor—A scaling factor will be used to resample the cached raster. This is the default, and the default factor is 1, so that no scaling takes place.
  • Pixel Size—The pixel size at which the cached raster will be created.

Request Size

The pixel size at which the cached raster will be created.

The default value is 1.


In this topic
  1. Overview
  2. Notes
  3. Parameters