我是谷歌MLKit的新手，想检测Android和iOS的账单/收据，我使用X1 E0 F1 X和X1 E1 F1 X。
检测由Google MLkit完成，然后由react-native-vision-camera解释
在java中的android上我没有问题，账单被很好地检测到：
Image
在iOS上，对于相同的代码（但使用Objective C而不是Java），我从未检测到发票：
Image

#import <Foundation/Foundation.h>
#import <VisionCamera/FrameProcessorPlugin.h>
#import <VisionCamera/Frame.h>
#import <MLKit.h>

@interface VisionScanObjectsFrameProcessorPlugin : NSObject
+ (MLKObjectDetector*) objectDetector;
@end

@implementation VisionScanObjectsFrameProcessorPlugin

+ (MLKObjectDetector*) objectDetector {
  static MLKObjectDetector* objectDetector = nil;
  if (objectDetector == nil) {
    NSString *path = [[NSBundle mainBundle] pathForResource:@"lite-model_object_detection_mobile_object_labeler_v1_1" ofType:@"tflite"];
    MLKLocalModel *localModel = [[MLKLocalModel alloc] initWithPath:path];

    MLKCustomObjectDetectorOptions *options = [[MLKCustomObjectDetectorOptions alloc] initWithLocalModel:localModel];
    options.detectorMode = MLKObjectDetectorModeSingleImage;
    options.shouldEnableClassification = YES;
    options.classificationConfidenceThreshold = @(0.5);
    options.maxPerObjectLabelCount = 3;

    objectDetector = [MLKObjectDetector objectDetectorWithOptions:options];
  }

  return objectDetector;
}

static inline id scanObjects(Frame* frame, NSArray* arguments) {
  MLKVisionImage *image = [[MLKVisionImage alloc] initWithBuffer:frame.buffer];
  image.orientation = frame.orientation; // <-- TODO: is mirrored?

  NSError* error;
  NSArray<MLKObject*>* objects = [[VisionScanObjectsFrameProcessorPlugin objectDetector] resultsInImage:image error:&error];

  NSLog(@"Object detected : %ld", objects.count);

  NSMutableArray* results = [NSMutableArray arrayWithCapacity:objects.count];
  for (MLKObject* object in objects) {
    NSMutableArray* labels = [NSMutableArray arrayWithCapacity:object.labels.count];

    for (MLKObjectLabel* label in object.labels) {
      if (122 == label.index || 188 == label.index || 288 == label.index || 325 == label.index || 357 == label.index || 370 == label.index || 480 == label.index || 510 == label.index || 551 == label.index) {
        [labels addObject:@{
          @"index": [NSNumber numberWithFloat:label.index],
          @"label": label.text,
          @"confidence": [NSNumber numberWithFloat:label.confidence]
        }];
      }
    }

    if (labels.count != 0) {
      [results addObject:@{
        @"width": [NSNumber numberWithFloat:object.frame.size.width],
        @"height": [NSNumber numberWithFloat:object.frame.size.height],
        @"top": [NSNumber numberWithFloat:object.frame.origin.y],
        @"left": [NSNumber numberWithFloat:object.frame.origin.x],
        @"frameRotation": [NSNumber numberWithFloat:frame.orientation],
        @"labels": labels
      }];
    }
  }

  return results;
}

VISION_EXPORT_FRAME_PROCESSOR(scanObjects)

@end

我真的认为这段代码可以工作，因为我没有任何崩溃（在它工作之前^^我有），但我从来没有检测到一个文档。：/
NSLog(@"Object detected : %ld", objects.count);几乎总是return 0。**例外的是，它将return 1**检测我的电脑键盘，但这是非常非常罕见的。
在过去的4天里，我尝试了很多方法（different model、异步检测、检测前调整大小等），但还是一样：/