detectFromMatBytes method

Future<List<Hand>> detectFromMatBytes(Uint8List bytes, { required int width, required int height, int matType = 16, })

Detects hands from raw pixel bytes without constructing a cv.Mat first.

This avoids the overhead of building a Mat on the calling thread: the bytes are transferred via zero-copy TransferableTypedData and the Mat is reconstructed inside the background isolate.

Parameters:

• bytes: Raw pixel data (typically BGR format, 3 bytes per pixel)
• width: Image width in pixels
• height: Image height in pixels
• matType: OpenCV MatType value (default: CV_8UC3 = 16 for BGR)

Returns a list of Hand objects, one per detected hand.

Throws StateError if called before initialize.

Implementation

Future<List<Hand>> detectFromMatBytes(
  Uint8List bytes, {
  required int width,
  required int height,
  int matType = 16,
}) async {
  if (!isReady) {
    throw StateError(
        'HandDetector not initialized. Call initialize() first.');
  }
  final List<dynamic> result = await _worker!.sendRequest<List<dynamic>>(
    'detectMat',
    {
      'bytes': TransferableTypedData.fromList([bytes]),
      'width': width,
      'height': height,
      'matType': matType,
    },
  );
  return _deserializeHands(result);
}