Add Tiled .TIFF Support #60
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… code some more, including separating out the sample function so that the readTileData now supports all data formats as well. Added some comments for clarity.
Codecov ReportAttention: Patch coverage is
Additional details and impacted files@@ Coverage Diff @@
## main #60 +/- ##
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- Coverage 79.89% 74.66% -5.23%
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Files 12 12
Lines 562 604 +42
Branches 110 120 +10
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+ Hits 449 451 +2
- Misses 106 144 +38
- Partials 7 9 +2 ☔ View full report in Codecov by Sentry. |
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Attached are two sample images which have different tiled layouts for testing, from different sources (one from Upper Austria DGM and one from SwissALTI3D). |
… code some more, including separating out the sample function so that the readTileData now supports all data formats as well. Added some comments for clarity.
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For some reason, github is not correctly updating the diff after I rebased the branch. The files changed are clearly incorrect (at time of writing). |
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The main branch in your repo is out of sync with this one so rebasing with your main branch adds changes unrelated to this PR on this branch. |
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I realized this. The PR was closed, I synced my main branch, branched and readded the changes. A new PR #62 has been opened. |
This PR adds support for tiled .TIFF files. This is related to issue #58. If merged, the API remains unchanged but the feature is then supported.
This has been tested and works for a number of datasets from SwissALTI3D and DGM Data from the Upper Austrian government.
The implementation mimics the implementation of
readStripDataasreadTileData. To reduce duplicate code, the decompression switch was isolated into a separate function.Additionally, the
fillXfunctions were removed, as they only work with linearized data / the assumption of a linear index. Instead, they were replaced with a singlesampleValuefunction, which can be called directly inreadStripDataorreadTileDatawith the specific indexing procedure while still being extensible to support more formats.There is a minor consideration that the "check" which is the stored format is now performed once per iteration, instead of calling a specialized function once (per strip) which is iterated inside. These checks could be removed by selecting a callback once at the beginning of the function and using that to sample the value. I am not sure what is more performant in transpiled typescript though, de-referencing an additional callback or 3 if statements. I didn't want to introduce more / opinionated code than necessary, so this is the "minimum viable" change.
The tile reading implementation can be compared to libtiff in C/C++ here and here.