00001 //# ImageAttrHandlerCasa.h: Attributes handler for CASA images 00002 //# Copyright (C) 2012 00003 //# Associated Universities, Inc. Washington DC, USA. 00004 //# 00005 //# This library is free software; you can redistribute it and/or modify it 00006 //# under the terms of the GNU Library General Public License as published by 00007 //# the Free Software Foundation; either version 2 of the License, or (at your 00008 //# option) any later version. 00009 //# 00010 //# This library is distributed in the hope that it will be useful, but WITHOUT 00011 //# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 00012 //# FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public 00013 //# License for more details. 00014 //# 00015 //# You should have received a copy of the GNU Library General Public License 00016 //# along with this library; if not, write to the Free Software Foundation, 00017 //# Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA. 00018 //# 00019 //# Correspondence concerning AIPS++ should be addressed as follows: 00020 //# Internet email: aips2-request@nrao.edu. 00021 //# Postal address: AIPS++ Project Office 00022 //# National Radio Astronomy Observatory 00023 //# 520 Edgemont Road 00024 //# Charlottesville, VA 22903-2475 USA 00025 //# 00026 //# $Id$ 00027 00028 #ifndef IMAGES_IMAGEATTRHANDLERCASA_H 00029 #define IMAGES_IMAGEATTRHANDLERCASA_H 00030 00031 00032 //# Includes 00033 #include <casacore/casa/aips.h> 00034 #include <casacore/images/Images/ImageAttrHandler.h> 00035 #include <casacore/images/Images/ImageAttrGroupCasa.h> 00036 #include <map> 00037 00038 namespace casacore { 00039 00040 // <summary> 00041 // Abstract base class for an image attributes handler. 00042 // </summary> 00043 00044 // <use visibility=export> 00045 00046 // <reviewed reviewer="" date="" tests="tPagedmage.cc" demos="dPagedImage.cc"> 00047 // </reviewed> 00048 00049 // <prerequisite> 00050 // <li> <linkto class=ImageInterface>ImageInterface</linkto> 00051 // </prerequisite> 00052 00053 // <etymology> 00054 // This class makes it possible to store extra attributes with an image to 00055 // describe atrbitrary meta information. 00056 // </etymology> 00057 00058 // <synopsis> 00059 // For LOFAR it was needed to store extra meta information and to be able to 00060 // convert it from casacore table format to HDF5 format and vice-versa. 00061 // Furthermore, it must be possible to access the information in a way that 00062 // arbitrary info can be stored and retrieved. 00063 // 00064 // The attributes are divided into handlers. Each handler can reside in a subtable 00065 // of the image or in a handler in HDF5. All attributes in a handler have the 00066 // same number of values, where each value can be a scalar or (small) array. 00067 // It is possible to define units and measure info for an attribute. 00068 // </synopsis> 00069 00070 // <example> 00071 // This example shows how to get attributes from an image. 00072 // make it known to the image. 00073 // <srcblock> 00074 // // Open the image (as readonly for the moment). 00075 // PagedImage<Float> myimage ("image.name"); 00076 // // Get access to attibute handler LOFAR_SOURCE. 00077 // ImageExtrAttr& = myimage.attrHandler ("LOFAR_SOURCE"); 00078 // // Get the data for some field. 00079 // Vector<String> names = ImageExtrAttr->getString("NAME"); 00080 // </srcblock> 00081 // </example> 00082 // 00083 // <motivation> 00084 // LOFAR needed functionality to store arbitrary attributes. 00085 // </motivation> 00086 00087 class ImageAttrHandlerCasa : public ImageAttrHandler 00088 { 00089 public: 00090 // Default construct from the image table. 00091 ImageAttrHandlerCasa(); 00092 00093 // Attach the table and return this object. 00094 // It looks for the table keyword ATTRGROUPS which contains the subtables 00095 // defining the attribute groups. 00096 // If the keyword does not exist, it will be added if <src>createHandler</src> 00097 // is set. 00098 // Otherwise the handler is an empty one and no groups can be added to it. 00099 ImageAttrHandlerCasa& attachTable (const Table& image, 00100 Bool createHandler = False); 00101 00102 virtual ~ImageAttrHandlerCasa(); 00103 00104 // Flush the attibrutes if needed. 00105 virtual void flush(); 00106 00107 // Test if the given attribute group is present. 00108 virtual Bool hasGroup (const String& name); 00109 00110 // Get all attribute group names. 00111 virtual Vector<String> groupNames() const; 00112 00113 // Get access to a group. 00114 virtual ImageAttrGroup& openGroup (const String& groupName); 00115 00116 // Create an attribute group with the given name. 00117 virtual ImageAttrGroup& createGroup (const String& groupName); 00118 00119 // Close the group with the given name. It will flush its attributes. 00120 // Nothing is done if it is not open. 00121 virtual void closeGroup (const String& groupName); 00122 00123 private: 00124 Bool itsCanAdd; //# can groups be added? 00125 Table itsImageTable; //# Table object of image 00126 std::map<String,ImageAttrGroupCasa> itsGroupMap; //# attribute groups 00127 }; 00128 00129 } //# NAMESPACE CASACORE - END 00130 00131 #endif