Fix read_geotiff_gpu byteswap on big-endian multi-byte TIFFs#1515
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brendancol wants to merge 1 commit intoxarray-contrib:mainfrom
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Fix read_geotiff_gpu byteswap on big-endian multi-byte TIFFs#1515brendancol wants to merge 1 commit intoxarray-contrib:mainfrom
brendancol wants to merge 1 commit intoxarray-contrib:mainfrom
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cupy.ndarray (13.x) does not expose .byteswap(), so any BE multi-byte TIFF hit AttributeError inside the GPU decode pipeline. The dispatcher in read_geotiff_gpu caught it and silently fell back to CPU, so output stayed correct but the GPU path was effectively dead for BE data. Replace both arr.byteswap() calls with a small helper that views the array as the swapped-order dtype and copies, which works on numpy and cupy arrays alike. Closes xarray-contrib#1508
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Summary
Closes #1508.
cupy.ndarray(13.x) has no.byteswap()method, so any big-endian multi-byte TIFF was hittingAttributeErrorinside the GPU decode pipeline. The outertry/exceptinread_geotiff_gpuate the error and quietly fell back to CPU, so users got correct results but lost the GPU fast path on BE data.This swaps both
arr.byteswap()calls in_gpu_decode.pyfor a small helper that views the array as the swapped-order dtype and copies. Works on both.What changed
_gpu_decode.py: added_xp_byteswap(arr)helper, called at the two BE byteswap sites.tests/test_gpu_byteswap_1508.py: new GPU regression test. Reads a BE TIFF (uint16, int16, uint32, int32, plus uncompressed uint16) viaread_geotiff_gpu, asserts the result is a CuPy DataArray (not a NumPy fallback from a swallowed crash), and matches the CPU read.Out of scope
The outer
try/except Exceptioninread_geotiff_gputhat turns GPU errors into silent CPU fallback is itself worth revisiting; that's how this bug went undetected. Not touching it here. Filing as a follow-up.GPU predictor=2 on BE data is also broken, but in a separate way: the predictor kernel decodes the byte stream as native LE before the byteswap. That's a kernel-level issue, not a byteswap one. Also a follow-up.
Test plan
pytest xrspatial/geotiff/tests/test_gpu_byteswap_1508.py -q-> 5 passedpytest xrspatial/geotiff/tests/ -q-> 695 passed, 4 skipped (3 pre-existing matplotlib palette failures unrelated)