Filling Out the Imaging Dictionary Classes

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The imaging dictionary is a discipline dictionary, which means that its classes will appear in the <Discipline_Area> at the bottom of the <Observation_Area> in observational product labels (and in the <Context_Area>, if appropriate, in non-observational products). The classes in this dictionary provide parameters and processing information specific to image-type data, which includes data produced by imagers, but also instrument like imaging spectrometers.

The standard abbreviation for the namespace defined by this dictionary is "img:".

Begin: 13 August 2017 for version 1.7.0.0 Working: 24 June 2018 for version 1.9.0.0

<Imaging>

REQUIRED

This is the wrapper class for the Imaging Dictionary. It must be used whenever you want or need to include imaging acquisition or processing parameters in your product label. It has four subclasses, listed below, each of which may be omitted or repeated as appropriate for your data product. The subclasses are fairly complex, so each is described on its own page.

<pds:Local_Internal_Reference>

REQUIRED

This class ties the imaging descriptions following to a specific image-type object described elsewhere in the product label. This class and its attributes are in the core PDS namespace, and so are described here using the standard "pds:" prefix. How you reference them in your product label depends on the conventions you're using for namespace references. If you're not sure what that means, see Schema Referencing in PDS Labels: Namespace References elsewhere on this wiki.

Repeat this class once for each image-type object that you want to tie to this <Imaging> class.

<pds:comment>

OPTIONAL

If there are any caveats or special circumstances about this reference that you want to note for end-users, this is the place to do it.

<pds:local_identifier_reference>

REQUIRED

This attribute must contain a string that appears in the <local_identifier> attribute of an image-type object elsewhere in this label.

Note: There is no validation that checks if the local_identifier belongs to an image-type object. Type carefully.

<pds:local_reference_type>

REQUIRED

This attribute must have the value imaging_parameters_to_image_object.

<Command_Parameters>

OPTIONAL

The attributes in this class define the commands sent to the spacecraft. These commanded values may or may not correspond to the actual, observational values. The actual values should be provided in the <Image_Product_Information> class, following.

<Image_Product_Information>

OPTIONAL

This class contains attributes describing the image itself, including parameters for exposure, filter description, sampling, framing, and so on.

<Imaging_Instrument_State_Parameters>

OPTIONAL

This class contains attributes describing the instrument that obtained the data, including field of view, various mode settings, commanding, and telemetry parameters.

<Image_Compression_Parameters>

OPTIONAL

This class contains attributes describing onboard compression.