Pillow on Android: is libtiff support expected for JPEG-compressed TIFFs?

[GalileoAlmeria]

Hi Feodor and Flet team,

First of all, thank you for the excellent work on Flet — especially the mobile packaging and the growing set of pre-built binary packages. In a previous case you helped us resolve a related packaging issue quickly, which we really appreciated.

We are building a weather-radar visualisation app (AEMET data) with Flet 1.0.4. The same code works correctly on Windows but fails on Android when reading regional PPI radar products.

Observed behaviour

Windows (Pillow 12.3.0):
libtiff=True → JPEG-compressed TIFF (compression=7) loads fine.

Android (Pillow 12.2.0, built with flet build apk):
libtiff=False →
OSError: decoder libtiff not available

Uncompressed palette TIFFs (the national composite) work on both platforms. Only the JPEG-in-TIFF PPI files fail on Android.

Quick summary of the files

Product Compression Mode Result on Android
National composite 1 (none) P OK
Regional PPI 7 (JPEG) RGBA decoder libtiff not available

We confirmed that download, file selection and coordinate handling all succeed; the failure occurs only at Image.load().

Question

Flet already publishes both pillow and flet-libtiff wheels on pypi.flet.dev.
Is libtiff support expected to be enabled in the Android Pillow builds?
If it is, could you advise on the recommended way to ensure the decoder is available (extra dependency, build flag, etc.)?
If it is intentionally disabled or still work-in-progress, we will look for alternative approaches (server-side conversion, etc.).

I have prepared a minimal reproducible example (code + sample JPEG-compressed TIFF) and attached it as a zip file.

Thank you very much for any guidance.

Best regards,
Galileo

reproduccion_minima_pillow_tiff.zip

[ndonkoHenri]

Thanks for the clear report and the repro.

Pillow’s mobile build simply wasn’t linking libtiff, even though libtiff was already on the index. We have now published Pillow 12.3.0 build 1, which links it, so JPEG-, LZW- and deflate-compressed TIFFs now decode on Android and iOS.

Rebuild your app and let us know.

[GalileoAlmeria]

Thank you very much, ndonkoHenri (and the whole Flet team)!

I just rebuilt the APK with the new Pillow 12.3.0 build 1 and confirmed that JPEG-compressed TIFFs now load correctly on Android. The "decoder libtiff not available" error is gone and the radar PPI images work as expected.

Really impressive how quickly you identified the missing link and published the fixed build. Your support on mobile packaging continues to be outstanding.

Thanks again for the excellent work!

Best regards,
Galileo