flutter_internal/lib/common/transform.dart

import 'dart:io';
import 'dart:ui';
import 'package:google_mlkit_object_detection/google_mlkit_object_detection.dart';

double translateX(double x, InputImageRotation rotation, Size size, Size absoluteImageSize) {
  switch (rotation) {
    case InputImageRotation.rotation90deg:
      return x * size.width / (Platform.isIOS ? absoluteImageSize.width : absoluteImageSize.height);
    case InputImageRotation.rotation270deg:
      return size.width - x * size.width / (Platform.isIOS ? absoluteImageSize.width : absoluteImageSize.height);
    default:
      return x * size.width / absoluteImageSize.width;
  }
}

double translateY(double y, InputImageRotation rotation, Size size, Size absoluteImageSize) {
  switch (rotation) {
    case InputImageRotation.rotation90deg:
    case InputImageRotation.rotation270deg:
      return y * size.height / (Platform.isIOS ? absoluteImageSize.height : absoluteImageSize.width);
    default:
      return y * size.height / absoluteImageSize.height;
  }
}