casacore
ImageAttrHandlerHDF5.h
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1//# ImageAttrHandlerHDF5.h: Attributes handler for HDF5 images
2//# Copyright (C) 2012
3//# Associated Universities, Inc. Washington DC, USA.
4//#
5//# This library is free software; you can redistribute it and/or modify it
6//# under the terms of the GNU Library General Public License as published by
7//# the Free Software Foundation; either version 2 of the License, or (at your
8//# option) any later version.
9//#
10//# This library is distributed in the hope that it will be useful, but WITHOUT
11//# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12//# FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
13//# License for more details.
14//#
15//# You should have received a copy of the GNU Library General Public License
16//# along with this library; if not, write to the Free Software Foundation,
17//# Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA.
18//#
19//# Correspondence concerning AIPS++ should be addressed as follows:
20//# Internet email: aips2-request@nrao.edu.
21//# Postal address: AIPS++ Project Office
22//# National Radio Astronomy Observatory
23//# 520 Edgemont Road
24//# Charlottesville, VA 22903-2475 USA
25//#
26//# $Id$
27
28#ifndef IMAGES_IMAGEATTRHANDLERHDF5_H
29#define IMAGES_IMAGEATTRHANDLERHDF5_H
30
31
32//# Includes
33#include <casacore/casa/aips.h>
34#include <casacore/images/Images/ImageAttrHandler.h>
35#include <casacore/images/Images/ImageAttrGroupHDF5.h>
36#include <casacore/casa/HDF5/HDF5Group.h>
37#include <casacore/casa/Utilities/CountedPtr.h>
38#include <map>
39
40namespace casacore {
41
42// <summary>
43// Abstract base class for an image attributes handler.
44// </summary>
45
46// <use visibility=export>
47
48// <reviewed reviewer="" date="" tests="tPagedmage.cc" demos="dPagedImage.cc">
49// </reviewed>
50
51// <prerequisite>
52// <li> <linkto class=ImageInterface>ImageInterface</linkto>
53// </prerequisite>
54
55// <etymology>
56// This class makes it possible to store extra attributes with an image to
57// describe atrbitrary meta information.
58// </etymology>
59
60// <synopsis>
61// For LOFAR it was needed to store extra meta information and to be able to
62// convert it from casacore table format to HDF5 format and vice-versa.
63// Furthermore, it must be possible to access the information in a way that
64// arbitrary info can be stored and retrieved.
65//
66// The attributes are divided into handlers. Each handler can reside in a subtable
67// of the image or in a handler in HDF5. All attributes in a handler have the
68// same number of values, where each value can be a scalar or (small) array.
69// It is possible to define units and measure info for an attribute.
70// </synopsis>
71
72// <example>
73// This example shows how to get attributes from an image.
74// make it known to the image.
75// <srcblock>
76// // Open the image (as readonly for the moment).
77// PagedImage<Float> myimage ("image.name");
78// // Get access to attibute handler LOFAR_SOURCE.
79// ImageExtrAttr& = myimage.attrHandler ("LOFAR_SOURCE");
80// // Get the data for some field.
81// Vector<String> names = ImageExtrAttr->getString("NAME");
82// </srcblock>
83// </example>
84//
85// <motivation>
86// LOFAR needed functionality to store arbitrary attributes.
87// </motivation>
88
90{
91public:
92 // Default construct from the image table.
94
95 // Attach the table and return this object.
96 // It looks for the table keyword ATTRGROUPS which contains the subtables
97 // defining the attribute groups.
98 // If the keyword does not exist, it will be added if <src>createHandler</src>
99 // is set.
100 // Otherwise the handler is an empty one and no groups can be added to it.
102 Bool createHandler = False);
103
105
106 // Attach the hid and return this object.
107 // It looks for the group ATTRGROUPS which contains groups
108 // defining the attribute groups.
109 // If the group does not exist, it will be added if <src>createHandler</src>
110 // is set.
111 // Otherwise the handler is an empty one and no groups can be added to it.
113 Bool createHandler,
114 Bool isWritable);
115
116 // Flush the attibrutes if needed.
117 virtual void flush();
118
119 // Test if the given attribute group is present.
120 virtual Bool hasGroup (const String& name);
121
122 // Get all attribute group names.
123 virtual Vector<String> groupNames() const;
124
125 // Get access to a group.
126 virtual ImageAttrGroup& openGroup (const String& groupName);
127
128 // Create an attribute group with the given name.
129 virtual ImageAttrGroup& createGroup (const String& groupName);
130
131 // Close the group with the given name. It will flush its attributes.
132 // Nothing is done if it is not open.
133 virtual void closeGroup (const String& groupName);
134
135private:
136 Bool itsCanWrite; //# writable?
137 CountedPtr<HDF5Group> itsGroup; //# HDF5 group to add to
138 std::map<String,ImageAttrGroupHDF5> itsGroupMap; //# attribute groups
139};
140
141} //# NAMESPACE CASACORE - END
142
143#endif
Referenced counted pointer for constant data.
Definition: CountedPtr.h:81
virtual ImageAttrGroup & openGroup(const String &groupName)
Get access to a group.
virtual void flush()
Flush the attibrutes if needed.
ImageAttrHandlerHDF5 & attachTable(const Table &image, Bool createHandler=False)
Attach the table and return this object.
ImageAttrHandlerHDF5()
Default construct from the image table.
virtual ImageAttrGroup & createGroup(const String &groupName)
Create an attribute group with the given name.
virtual Vector< String > groupNames() const
Get all attribute group names.
ImageAttrHandlerHDF5 & attachHid(const HDF5Object &hid, Bool createHandler, Bool isWritable)
Attach the hid and return this object.
virtual Bool hasGroup(const String &name)
Test if the given attribute group is present.
std::map< String, ImageAttrGroupHDF5 > itsGroupMap
CountedPtr< HDF5Group > itsGroup
virtual void closeGroup(const String &groupName)
Close the group with the given name.
String: the storage and methods of handling collections of characters.
Definition: String.h:225
this file contains all the compiler specific defines
Definition: mainpage.dox:28
const Bool False
Definition: aipstype.h:44
bool Bool
Define the standard types used by Casacore.
Definition: aipstype.h:42