I have prepared a (lengthy) document that describes the MapInfo Virtual Raster (MVR) format. It should be used in conjunction with MapInfo Pro 2019 Patch 3, due to be released in October 2020. Some of the features described in this document will not be available in previous releases.
An MVR file is an XML text file that you can load into MapInfo Pro in just the same way that you load any other raster format. Pro will create a TAB file to accompany the MVR file when you first mount it.
This document also describes how to write rendering algorithms. Rendering algorithms can be embedded in an MVR and will usually be the raster source for an "Image" field in an MVR.
An MRD file is an XML text file that contains a rendering algorithm. You can load an MRD into MapInfo Pro in just the same way that you load any other raster format. Pro will create a TAB file to accompany the MRD file when you first mount it. This document does not cover MRD files explicitly, but the XML for a rendering algorithm is fully described.
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Sam Roberts
Engineer, MapInfo Pro Advanced (Raster)
Australia
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