/**
\page History
\section history History
<PRE>
2005-01-04 1.0.0 Vesa Oikonen, Calle Laakkonen, Riku Klén, Jarkko Johansson
	Former libpet, the common PET C library, has been divided up in smaller
	sublibraries that each handle a specific task. This library includes functions
	utilised in image file input and output procedures. 

2005-03-03 1.0.0 Jarkko Johansson 
	imgproc.[c/h] moved to libtpcimgp library

2005-04-05 1.0.1 (krs) Roman Krais
       interfile.c added (for reading interfile headers)

2005-04-25 1.1.0 Jarkko Johansson
	History and Readme files included in new print functions:
	libtpcimgio_print_readme(FILE *fp);
	libtpcimgio_print_history(FILE *fp);
	libtpcimgio_print_dreadme(FILE *fp);
	libtpcimgio_print_dhistory(FILE *fp);
	libtpcimgio_print_build(FILE *fp);
	in file libtpcimgio.c. Update the the Readme and History
	there.

	Compiled in Windows with MinGW.

2005-05-04 1.1.0 JJ
       Minor changes in file sifio.c.

2005-08-01 1.1.1 CL/JJ
       Changed image loading/writing functions fname to const,
       and extern int VOL_TEST to int VOL_TEST.

2005-10-10 1.1.2 CL
       imgWriteAnalyze() now writes only 1 frame at a time,
       conserving memory.

2005-11-21 1.1.3 VO
       lambda2factor() now calculates correctly when removing
       decay correction considering frame lengths.

2005-12-12 1.1.4 VO
       imgReadAnalyze() sets img.isotopeHalflife,
       if isotope is found in SIF.

2006-10-31 1.1.5 VO
       Added function imgUnitId().
       Fixed a timezone bug with ECAT7 files.

2006-12-28 1.1.6 VO
       Changes in identification of isotope codes.

2007-02-02 1.2.0 VO
       Additions in IMG structure, and subsequent changes in i/o functions.
       Isotope and halflife related functions are relocated into libtpcmisc.
       This library is now independent of libtpcimgp.
       IMG min and max search functions are relocated here.
       User_process_code is read/written with ECAT7 and ECAT6.3 files.
       Patient_id is read/written with ECAT7 and ECAT6.3 files.
       Study_description is read/written with ECAT7 and ECAT6.3 files.
       X, y and z resolution is read/written with ECAT7 images.
       Prompts and randoms (delayed) are read/written with ECAT7 and
       ECAT6.3 sinograms and read from SIF with Analyze 7.5.
       Changes in identifying and processing calibration units.

2007-02-11 1.2.1 VO
       Addition in IMG structure.
       Deleted imgmsg.h. Set IMG.statmsg using imgSetStatus().

2007-02-27 1.2.2 VO
       Bug corrections.

2007-03-13 1.2.3 VO
       Added ECAT matrix list functions and error messages.
       ECAT 6.3 header print format changed.

2007-03-21 1.2.4 VO
       Changes to make easier to write ECAT7 2D files.

2007-03-25 1.2.5 VO
       Addition of functions for reading and writing ECAT and Analyze
       format one frame at a time.

2007-04-03 1.3.0 VO
       Added support for ECAT7 polar maps.
       Information for polar map added to IMG struct.

2007-07-17 1.3.1 Harri Merisaari
       Modified for optional ANSI compatibility.

2007-09-10 1.3.2 VO
       Bug correction in setting error messages.
       Bug correction in reading some too long header text fields.

2007-09-10 1.3.3 VO
       Return value of localtime() is always checked.

2007-09-11 1.3.4 VO
       Corrected a bug affecting versions 1.3.1 -1.3.3:
       Analyze and ECAT files could have been mixed if in same folder.

2007-09-12 1.3.5 VO
       Corrected a bug affecting frame-by-frame reading of
       ECAT7 2D image files.

2008-07-07 1.3.6 VO
       Image decay correction functions return error if frame times
       are missing.
       Assumes that Analyze 7.5 images are corrected for decay when
       that information is not found in header file.

2008-07-11 1.3.7 VO
       Added function sifModerate().

2008-07-14 1.3.8 VO
       Added function imgAllocateWithHeader().

2008-07-24 1.3.9 VO
       Added functions ecat7EditMHeader(), ecat7EditSHeader(),
       ecat7EditVHeader(), imgSetUnit(), and ecat7PrintSubheader().

2008-09-02 1.4.0 VO
       Default ECAT backup extension changed to .bak.

2008-10-03 1.4.1 VO
       Accepts certain Analyze formats with 32 bit pixel values.

2008-10-09 1.4.2 VO
       Accepts more Analyze formats with 32 bit pixel values (PVElab).

2008-11-06 1.4.3 VO
       Bug correction in reading ECAT 6.3 files.

2009-02-17 1.5.0 VO
       Added definitions for Siemens Inveon in img.h.
       Added micropet.c and .h for reading Siemens Inveon images.

2009-02-25 1.5.1 VO
       Changes in micropet.c and .h to allow reading CT images.

2009-04-06 1.5.2 VO
       Changes in sif.c to allow SIF without prompts and randoms.

2009-09-28 1.5.3 VO
       Change in micropet.c reading pixel z size.

2009-12-01 1.5.4 VO
       Added function imgSmoothMax().

2009-12-10 1.5.5 VO
       Tiny update in img_ana.c.

2010-02-12 1.5.6 VO
       Time zone is corrected in imgSetEcat7MHeader().

2010-05-11 1.5.7 VO
       imgUnitFromEcat7() tries more to identify units.

2010-08-19 1.5.8 VO
       ECAT7 main header field patient_birth_date is read correctly
       whether is is in documented YYYYMMDD format or as seconds from
       start of years 1970.

2011-01-11 1.5.9 VO
       Bug fixes in reading micropet images.

2011-02-04 1.5.10 VO
       Label unitless was previously not written in main header
       when IMG data is written in ECAT7 format.

2011-08-12 1.5.11 VO
       Supports reading MicroPET images with header version 001.701
       (previously only 001.830).

2011-08-13 1.5.12 VO
       MicroPET frame times (sec) are read as floats.
       Frame times are saved in SIF with one decimal when necessary.

2011-08-17 1.5.13 VO
       Changed exp_date format in Analyze header to prevent overflow.


</PRE> 
 */
