iphone - 我正在使用 ZXingObjC 库从图像中读取条形码，但它没有返回任何结果我使用的代码如下

Question

-(void)decode:(CVImageBufferRef)BufferRef
{

  NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];

  CGImageRef videoFrameImage = [ZXCGImageLuminanceSource createImageFromBuffer:BufferRef];

  CGImageRef rotatedImage = [self rotateImage:videoFrameImage degrees:0.0f];

  [NSMakeCollectable(videoFrameImage) autorelease];

  //Decoding:
  ZXLuminanceSource* source = [[[ZXCGImageLuminanceSource alloc]     initWithCGImage:rotatedImage] autorelease];

  [NSMakeCollectable(rotatedImage) autorelease];

  ZXBinaryBitmap* bitmap = [ZXBinaryBitmap binaryBitmapWithBinarizer:[ZXHybridBinarizer binarizerWithSource:source]];

  NSError* error = nil;

  // There are a number of hints we can give to the reader, including

  // possible formats, allowed lengths, and the string encoding.

  ZXDecodeHints* hints = [ZXDecodeHints hints];

  ZXMultiFormatReader* reader = [ZXMultiFormatReader reader];

  ZXResult* result = [reader decode:bitmap
                              hints:hints
                              error:&error];
  if (result) 
  {

    // The coded result as a string. The raw data can be accessed with

    // result.rawBytes and result.length.

    NSString* contents = result.text;

    // The barcode format, such as a QR code or UPC-A

    ZXBarcodeFormat format = result.barcodeFormat;

  } 

  else 

  {

    // Use error to determine why we didn't get a result, such as a barcode

    // not being found, an invalid checksum, or a format inconsistency.
  }


  [pool drain];

}

Answer 1

我遇到了这个问题，可以通过对相机生成的图像进行下采样轻松解决。显然，图书馆处理条形码的分辨率太高了。通过在调用 [image CGImage] 之前将我的 UIImage 的大小减小到 640x480，一切正常。

Answer 2

您已经评论说您应该使用错误来确定您没有得到结果的原因，但您实际上并没有这样做。看看里面有什么error。