1 /*=========================================================================
2  *
3  *  Copyright Insight Software Consortium
4  *
5  *  Licensed under the Apache License, Version 2.0 (the "License");
6  *  you may not use this file except in compliance with the License.
7  *  You may obtain a copy of the License at
8  *
9  *         http://www.apache.org/licenses/LICENSE-2.0.txt
10  *
11  *  Unless required by applicable law or agreed to in writing, software
12  *  distributed under the License is distributed on an "AS IS" BASIS,
13  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  *  See the License for the specific language governing permissions and
15  *  limitations under the License.
16  *
17  *=========================================================================*/
18 #ifndef itkRealTimeClock_h
19 #define itkRealTimeClock_h
20 
21 #include "itkMacro.h"
22 #include "itkObject.h"
23 #include "itkObjectFactory.h"
24 #include "itkRealTimeStamp.h"
25 
26 namespace itk
27 {
28 /** \class RealTimeClock
29  * \brief Provides a timestamp from a real-time clock.
30  *
31  * This class represents a real-time clock object
32  * and provides a timestamp in platform-independent format.
33  *
34  * \author Hee-Su Kim, Compute Science Dept. Kyungpook National University,
35  *                     ISIS Center, Georgetown University.
36  * \ingroup ITKCommon
37  */
38 
39 class ITKCommon_EXPORT RealTimeClock:public Object
40 {
41 public:
42   using Self = RealTimeClock;
43   using Superclass = Object;
44   using Pointer = SmartPointer< Self >;
45   using ConstPointer = SmartPointer< const Self >;
46 
47   /** Method for defining the name of the class */
48   itkTypeMacro(RealTimeClock, Object);
49 
50   /** Method for creation through the object factory */
51   itkNewMacro(Self);
52 
53   /** Define the type for the timestap */
54   using TimeStampType = double;
55 
56   /** Define the type for the frequency of the clock */
57   using FrequencyType = double;
58 
59   /** Returns a timestamp in seconds, e.g. 52.341243 seconds */
60   TimeStampType GetTimeInSeconds() const;
61 
62   /** Returns the frequency of a clock */
63   itkGetConstMacro(Frequency, FrequencyType);
64 
65   /** Get the time as a RealTimeStamp type. */
66   RealTimeStamp GetRealTimeStamp() const;
67 
68 protected:
69 
70   /** Constructor. */
71   RealTimeClock();
72 
73   /** Destructor. */
74   ~RealTimeClock() override;
75 
76   void PrintSelf(std::ostream & os, Indent indent) const override;
77 
78 private:
79   FrequencyType m_Frequency{1};
80   TimeStampType m_Difference;
81   TimeStampType m_Origin;
82 
83   // Returns a timestamp in a TimeStamp data structure.
84   // We hide this method in the private section, because it returns the
85   // modified time of the itk::Object. That modified time is ambiguous with
86   // the role of the RealTimeStamp.
87   const TimeStamp & GetTimeStamp() const override;
88 };
89 } // end of namespace itk
90 
91 #endif  // itkRealTimeClock_h
92