TIFFSETTAGEXTENDER(3tiff)

✨ TIFFSETTAGEXTENDER ✨

ok so bestie, you know how we're deep in the 3tiff manual section (LibTIFF girlies rise up 💅) and you want libtiff to actually know about your little custom tags? yeah. this is the page for that. let's go 🎀

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🌸 NAME 🌸

TIFFSetTagExtender — registers the merge function for user defined tags as an extender callback with libtiff 🦋

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💖 SYNOPSIS 💖

#include <tiffio.h>

TIFFExtendProc TIFFSetTagExtender(TIFFExtendProc extender)

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✨ DESCRIPTION ✨

ok so TIFFSetTagExtender() is literally the vibe-setter for your custom tags 🫶 you use it to register the merge function for user defined tags as an extender callback with libtiff. that's it. that's the whole job. queen behavior.

if you want a lil more context on the whole thing, there's a brief description hanging out over at Defining Application Tags 📚 go read it, i'll wait 💜

⚠️ NOTE: TIFFSetTagExtender() can NOT be used to extend custom directories (like EXIF, GPS or other custom directories, bestie, don't even try it 😭). Only the TIFF directory can be extended with additional tags. that's the rule. periodt.

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👀 SEE ALSO 👀

• libtiff (3tiff)
• Defining New TIFF Tags (3tiff)
• TIFFMergeFieldInfo (3tiff)

go read those too, iykyk 🧚

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💜 AUTHOR 💜

LibTIFF contributors — the collective main characters who made all this happen 👑

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🎀 COPYRIGHT 🎀

1988-2025, LibTIFF contributors

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ok that's the whole page bestie, you ate that 🍓 mwah 💋

this was LibTIFF version 4.7, dated Jun 27, 2026 — catch you in the next manpage, no cap ✨🌈💖