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https://issues.apache.org/jira/browse/IMAGING-311?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17426357#comment-17426357
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Gary Lucas commented on IMAGING-311:
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I've made some progress on this issue and have submitted a pull-request to
Commons Imaging. A bit more work is still required (mostly additional JUnit
tests and a few missing accessor methods).
This change will enable Imaging to support additional data sets such as the
National Bathymetry System GeoTIFF raster products. These products give ocean
depth as a combination of depth and accuracy. The attached picture illustrates
the concept. The terrestrial features are from work that was done for
Imaging-251, but the oceanographic information comes from multi-variable
GeoTIFFs that were not previously accessible by the Imaging API (or any other
Java API that I know of).
!NBS_Example.jpg!
I built the imagery using a combination of Commons Imaging, some open-source
software I wrote to demonstrate [Shaded Relief Rendering
Techniques,|https://gwlucastrig.github.io/gridfour/notes/ElevationGeoTiff1.html]
and some geographic mapping modules I developed for my employer's Java-based
[wXstation|http://www.sonalysts.com/products/wxstation/] product.
> Read TIFFs with multiple floating-point samples
> -----------------------------------------------
>
> Key: IMAGING-311
> URL: https://issues.apache.org/jira/browse/IMAGING-311
> Project: Commons Imaging
> Issue Type: New Feature
> Components: Format: TIFF
> Affects Versions: 1.0-alpha3
> Environment:
> [IMAGING-251|https://issues.apache.org/jira/browse/IMAGING-251]
> Reporter: Gary Lucas
> Priority: Major
> Attachments: NBS_Example.jpg
>
>
> I propose to extend Commons Imaging to support reading TIFF files that
> contain floating-point formats that feature more than one sample. The
> ability to support floating-point samples was introduced in
> [ISSUE-251|https://issues.apache.org/jira/browse/IMAGING-251]. But that
> implementation was limited to only those files that provided a single sample
> per raster cell (e.g. "a single sample per pixel"). The ability to read files
> with multiple samples per raster cell would extend the usefulness of the
> Commons Imaging API, particularly for geophysical applications.
> If anyone knows of good sources for test TIFF files that use this format,
> please let me know.
> *Background*
> In addition to conventional image data, TIFF files can provide floating-point
> numerical information. This feature is often used for geophysical data (in
> GeoTIFF files), but can also be applied to other uses. Although the existing
> implementation can support files which give a single value per raster cell,
> there are some products that carry multiple samples per cell. Examples
> include products that give both a measured value and a corresponding accuracy
> estimate (i.e. 245.6 meters plus or minus 0.5 meters). Some geophysical
> products give vectors (gravitational potential, wind vectors, ocean currents,
> etc.).
> Changes would involve extensions to the classes in the TIFF datareader
> package as well as the TiffRasterData class.
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