detectNSFWFromImage method

Future<NsfwResult?> detectNSFWFromImage(Image image)

Detects NSFW content from an image

Inference runs synchronously on the calling isolate. Use compute() or another background isolate if you need to keep the UI responsive.

Implementation

Future<NsfwResult?> detectNSFWFromImage(img.Image image) async {
  if (_isClosed) throw StateError('NsfwDetector has been closed.');
  if (_isRunning) {
    throw StateError(
      'NsfwDetector is already running an inference. Concurrent calls are not supported.',
    );
  }
  _isRunning = true;
  try {
    final resizedImage = img.copyResize(
      image,
      width: _kInputWidth,
      height: _kInputHeight,
    );

    final inputBuffer = _imageToInputBuffer(resizedImage);
    final output = <List<double>>[List<double>.filled(2, 0.0)];

    _interpreter.run(inputBuffer, output);

    final result = output.first;
    if (result.length < 2) {
      throw NsfwDetectorException(
        'Model output has unexpected shape: expected at least 2 values.',
      );
    }

    final score = result[1];
    return NsfwResult(isNsfw: score > _threshold, score: score, safeScore: result[0]);
  } catch (error, stackTrace) {
    if (error is NsfwDetectorException) {
      rethrow;
    }
    throw NsfwDetectorException(
      'Failed to detect NSFW content from image.',
      cause: error,
      stackTrace: stackTrace,
    );
  } finally {
    _isRunning = false;
  }
}