I'm seeing a native crash from google_mlkit_face_detection that only happens in Android release builds.

Environment

• Flutter: (version)

• google_mlkit_face_detection: (version)

• google_mlkit_commons: (version)

• camera: (version)

• camera_android_camerax: (version)

• Android: 16

• Device: (device model)

Behavior

• Debug build works.

• Release build crashes.

• The crash occurs every time at:

final inputImage = InputImage.fromFilePath(capture.path);
final faces = await _detector.processImage(inputImage);

The image itself is valid.

Diagnostics show:

• Camera initializes successfully.

• takePicture() succeeds.

• JPEG exists on disk.

• JPEG header is valid.

• Dart successfully decodes the JPEG.

• InputImage.fromFilePath() succeeds.

• Crash occurs only when calling FaceDetector.processImage().

Relevant log sequence:

after_takePicture
capture_file_metadata
dart_decode_completed
before_inputImage_fromFilePath
after_inputImage_fromFilePath
before_detector_processImage
PlatformException:
Attempt to invoke virtual method
'java.lang.Class java.lang.Object.getClass()'
on a null object reference

Stack trace:

PlatformException(
error,
Attempt to invoke virtual method
'java.lang.Class java.lang.Object.getClass()'
on a null object reference,
...
FaceDetector.processImage(...)
)

Things already ruled out

• Storage permissions

• Camera permissions

• Corrupt JPEG

• Invalid image path

• Invalid file

• InputImage.fromFilePath() creation failure

I originally suspected InputImage.fromBytes, but my current code does not use it.

Current flow is:

takePicture()
↓
JPEG saved
↓
InputImage.fromFilePath(...)
↓
FaceDetector.processImage(...)
↓
Native NPE

Additional observations

• Debug works.

• Release fails.

• This strongly suggests either:

  • R8/minification

  • ML Kit native dependency issue

  • Android 16 compatibility issue

  • google_mlkit_face_detection regression

Has anyone encountered this exact release-only crash?

If this is an R8 issue, are there recommended keep rules for current ML Kit versions?