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Docs-level statements (imagebufalgo.md/.h) taken from producer reading.\n\nLimitations: Code/spec read at pinned commits 2026-10-22; nothing compiled or rendered.\n\nEvidence status: curator/producer inference or synthesis from the cited sources (code read, not executed, where code is cited); correlated desk review (Claude); not independently reviewed.","citations":[{"url":"https://github.com/AcademySoftwareFoundation/OpenImageIO/blob/febb1748a5a1b4f3da48d27aaae5a314b70c8f87/src/libOpenImageIO/imagebufalgo_xform.cpp","note":"OpenImageIO src/libOpenImageIO/imagebufalgo_xform.cpp at febb1748 (raw), L636, L723, L776; whole-file search"},{"url":"https://github.com/AcademySoftwareFoundation/OpenImageIO/blob/febb1748a5a1b4f3da48d27aaae5a314b70c8f87/src/include/OpenImageIO/imagebufalgo.h","note":"OpenImageIO src/libOpenImageIO/imagebufalgo_xform.cpp at febb1748 (raw), L636, L723, L776; whole-file search"},{"url":"https://github.com/AcademySoftwareFoundation/OpenImageIO/blob/febb1748a5a1b4f3da48d27aaae5a314b70c8f87/src/doc/imagebufalgo.md","note":"OpenImageIO src/libOpenImageIO/imagebufalgo_xform.cpp at febb1748 (raw), L636, L723, L776; whole-file search"}]},"tags":[],"type":"article","links":[],"title":"Which pixel-centre convention and alpha handling does OpenImageIO use in resize, resample and warp, and does resize premultiply?","rights":[{"notes":"Applies to this original summary only, not to the cited sources.","hosting":"permitted","component":"documentation","license_id":null,"modification":"unknown","evidence_urls":[],"model_training":"unknown","redistribution":"permitted"}],"summary":"OpenImageIO's resize/resample/warp code uses a half-pixel centre convention, and the transform file does no premultiplication: alpha is filtered like other channels unless the caller premultiplies (the docs provide separate premult/unpremult functions).","evidence":{"claims":[{"url":"https://github.com/AcademySoftwareFoundation/OpenImageIO/blob/febb1748a5a1b4f3da48d27aaae5a314b70c8f87/src/libOpenImageIO/imagebufalgo_xform.cpp","claim":"OpenImageIO's resize/resample/warp code uses a half-pixel centre convention, and the transform file does no premultiplication: alpha is filtered like other channels unless the caller premultiplies (the docs provide separate premult/unpremult functions).","locator":"OpenImageIO src/libOpenImageIO/imagebufalgo_xform.cpp at febb1748 (raw), L636, L723, L776; whole-file search","classification":"inference"}],"review":"unreviewed","execution":"not_run","inspection":"source_inspected","execution_record_ids":[]},"language":"en","categories":["T11","T12","T17"],"extensions":{"curation/v1":{"curator":"CURATOR-A-20261021","revision":1,"topic_ids":["CAT:T17.12"],"confidence":"Low for code facts.","limitations":["Code/spec read at pinned commits 2026-10-22; nothing compiled or rendered.","Source pin hashes are native catalogue descriptor hashes, not upstream byte hashes. 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