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Under the CSM standard, each plugin library can define its own ISD

camera model format. This library uses an auxiliary JSON formatted file that must

be next to the image file passed to the CSM::ISD class. We provide an

OpenAPI server for generating these,

[pfeffernusse](https://github.com/USGS-Astrogeology/pfeffernusse). The

swagger specification is located on

[swaggerhub](https://app.swaggerhub.com/apis/USGS-Astro/pfeffernusse2/0.1.4-oas3).

You can also use [ALE](https://github.com/USGS-Astrogeology/ale)

directly with metakernels to generate the auxiliary JSON file.

be next to the image file passed to the CSM::ISD class.

ISD files and strings can be generated by using [ALE](https://github.com/USGS-Astrogeology/ale)

with metakernels and accompanying SPICE kernels, or from ISIS cubes that have attached

SPICE data.

The camera model read from an ISD file is converted at load time to an

internal representation which makes camera operations more