}
		r = zr
		pr.closer = zr.IOReadCloser()
	case lz4Type:
		r = lz4.NewReader(scannedReader)
	case s2Type:
		r = s2.NewReader(scannedReader)
	case snappyType:
		r = s2.NewReader(scannedReader, s2.ReaderMaxBlockSize(64<<10))
	default:
		return nil, errInvalidCompressionFormat(fmt.Errorf("unknown compression type '%v'", compType))
	}
	pr.processedReader = newCountUpReader(r)

	return &pr, nil
}