tesseractOCR 识别数字问题

拍下图片再进行识别，所以如果图片的分辨率不高的话是无法准确识别的，那么在拍出来进行截取时，就需要保留原有的分辨率，确保图片不会严重失真（归根结底保证图片不失真）

处理图片方法：
/**
*将图片缩放到指定的CGSize大小
* UIImage image 原始的图片
* CGSize size 要缩放到的大小
*/
-(UIImage*)image:(UIImage *)image scaleToSize:(CGSize)size{

CGSize size1 = CGSizeMake(size.width * [UIScreen mainScreen].scale, size.height * [UIScreen mainScreen].scale);
UIGraphicsBeginImageContext(size1);
// 得到图片上下文，指定绘制范围
UIGraphicsBeginImageContext(size1);

// 将图片按照指定大小绘制
[image drawInRect:CGRectMake(0, 0, size1.width, size1.height)];

// 从当前图片上下文中导出图片
UIImage* scaledImage = UIGraphicsGetImageFromCurrentImageContext();

// 当前图片上下文出栈
UIGraphicsEndImageContext();


// 返回新的改变大小后的图片
return scaledImage;

}

/**
*从图片中按指定的位置大小截取图片的一部分
* UIImage image 原始的图片
* CGRect rect 要截取的区域
*/
-(UIImage )imageFromImage:(UIImage )image inRect:(CGRect)rect{

float a = [UIScreen mainScreen].scale;

//将UIImage转换成CGImageRef
CGImageRef sourceImageRef = [image CGImage];

//按照给定的矩形区域进行剪裁
CGImageRef newImageRef = CGImageCreateWithImageInRect(sourceImageRef, CGRectMake(rect.origin.x*a, rect.origin.y*a,rect.size.width*a, rect.size.height*a));

//将CGImageRef转换成UIImage
UIImage *newImage = [UIImage imageWithCGImage:newImageRef];

//返回剪裁后的图片
return newImage;

}

完整代码：

// 这是拍照按钮的方法
- (void)shutterCamera
{

NSLog(@"jnlai");

AVCaptureConnection *videoConnection = [self.stillImageOutput connectionWithMediaType:AVMediaTypeVideo];
if (!videoConnection) {
    return;
}

[self.stillImageOutput captureStillImageAsynchronouslyFromConnection:videoConnection completionHandler:^(CMSampleBufferRef imageDataSampleBuffer, NSError *error) {
    if (imageDataSampleBuffer == NULL) {
        return;
    }
    NSData *imageData = [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageDataSampleBuffer];
    UIImage *image = [UIImage imageWithData:imageData];
    NSLog(@"image size = %@ %lf %lf", NSStringFromCGSize(image.size),image.size.height,image.size.width);


    NSInteger h = screenHeigth-370-64*2-45-30;
    NSInteger w = screenWidth-90;

    UIImage* image1 = [Tools image:image scaleToSize:CGSizeMake(screenWidth, screenHeigth)];
    UIImage *image2= [Tools imageFromImage:image1 inRect:CGRectMake(45,  45, w, h)];



    [self recognizeImageWithTesseract:image2];



}];

}

-(void)recognizeImageWithTesseract:(UIImage *)image{

NSMutableArray *Marr = [NSMutableArray arrayWithCapacity:9];

dispatch_async(dispatch_get_global_queue(0, 0), ^{
    // 处理耗时操作的代码块...

    G8Tesseract *tesseract = [[G8Tesseract alloc] initWithLanguage:@"eng"];

    tesseract.image = [image g8_blackAndWhite];
    tesseract.engineMode = G8OCREngineModeCubeOnly;
    tesseract.charWhitelist = @"0123456789";

    [tesseract recognize];

    NSString *recognizedText = tesseract.recognizedText;

   NSArray *recognizeArr = [recognizedText componentsSeparatedByString:@"\n"];

    NSLog(@"arrarr %@",recognizeArr);

    NSString *temp =nil;


    for (NSString *str  in recognizeArr) {


        if ([self checkIsHaveNumAndLetter:str]>2) {


            NSMutableString *mStr = [[NSMutableString alloc]init];

            for(int i =0; i < [str length]; i++)
            {
                temp = [str substringWithRange:NSMakeRange(i,1)];

                if ([Tools deptNumInputShouldNumber:temp]) {

                    [mStr appendString:temp];
                }

                if ([temp isEqualToString:@"B"]) {

                    [mStr appendString:@"8"];
                }

                if ([temp isEqualToString:@"l"]) {

                    [mStr appendString:@"1"];
                }

                if ([temp isEqualToString:@"O"]||[temp isEqualToString:@"o"]) {

                    [mStr appendString:@"0"];
                }


            }

            if ([Tools checkLandline:mStr]||[Tools checkTel:mStr]) {
                [_Marr addObject:mStr];

                [Marr addObject:mStr];
            }


        }

    }



    NSLog(@"识别结果 \n %@",recognizedText);


    //通知主线程刷新
    dispatch_async(dispatch_get_main_queue(), ^{
        //回调或者说是通知主线程刷新，

        if (Marr.count !=0) {

            [_Marr addObjectsFromArray:Marr];
             _dataArr =  [self removeArray:_Marr].copy;
            [self To_CreateScanResultView];
        }



    });

});

}

在处理识别结果时最好先用”\n”分割成数组，会比较简单处理数据