NSTextAttachment add image blurred

In my rich text project I use NSTextAttachment to add an image, but the image is blurred.How to solve this problem? Thanks a lot.
Code Block if let image = UIImage(named: "tag") {
      let textAttachment = NSTextAttachment()
      textAttachment.image = image
      textAttachment.bounds = CGRect(origin: CGPoint.zero, size: image.size)
      let textAttachmentString = NSMutableAttributedString(attributedString: NSAttributedString(attachment: textAttachment))
      textAttachmentString.addAttribute(NSAttributedString.Key.paragraphStyle, value: paraph, range: NSRange(location: 0, length: textAttachmentString.length))
      attributedText.append(textAttachmentString)
  }


NSTextAttachment add image blurred
 
 
Q