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Gary Lucas commented on IMAGING-311: ------------------------------------ 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. -- This message was sent by Atlassian Jira (v8.3.4#803005)