Subject: Minutes of European FITS Committee Meeting, 1992 May 14-15

From: dwells at azalea.cx.nrao.edu (Don Wells)
Date: Thu, 11 Jun 1992 01:07:36 GMT

[NOTE- the two messages below were transmitted to "fitsbits"
yesterday, but did not explode due to a technical problem -Don]

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From: pgrosbol at eso.org
Subject: Minutes of European FITS Committee Meeting, 1992 May 14-15
Date: Tue, 09 Jun 92 13:27:28 +0200

                    Draft Minutes of 8th Meeting
                                 of
                      European FITS Committee
                       prepared by P.Grosbol
                         ESO, 1992-June-09

 The 8th meeting of the European FITS Committee was held in two
sessions during the 4th Data Analysis Workshop in ESO, May 14-15,
1992. The meeting was attended by 10-15 people with many FITS
Committee members e.g.  M.Currie, P.Grosbol, P.Kalberla, F.Pasian,
D.Ponz, E.Raimond, B.Peterson and D.Tody. The agenda was as follows:

        1) Status report (Chairman)
        2) Blocking Proposal
        3) Binary Table Extension
        4) Image Extension
        5) World Coordinates in FITS
        6) Any Other Business

Besides the general status report the main discussion was concerned
with the Blocking, BINTABLE and IMAGE Proposals. There were general
agreement on that the Proposals were acceptable and could be puts
forward to a vote in their present form. The more detailed issues
were:

 1) Status report: The annual report for 1991 of the IAU FITS Working
    Group was distributed and commented. The main issues were the
    IAU General Assembly, creation of the 'sci.astro.fits' news group
    by D.Wells, availability of anonymous ftp accounts with FITS
    documents, and the NASA FITS Support office including the
    draft of a standard document for 'Implementation of the FITS'.

    The main developments after this report are the official creation
    of the 'sci.astro.fits' news group, a final proposal for an IMAGE
    extension and the general discussion on the proposals through the 
    news group.

 2) Blocking: All expressed general agreement. The issue on whether
    or not 8mm Exabyte tapes should be defined as fixed or variable
    length was raised. There had not been extensive test of the
    fixed block QIC cartridges.

 3) BINTABLE: The data types were discussed with reference to
    arrays of string instead of only characters. The main argument
    for arrays of strings was the usage for defining units and
    types of multi-dimensional arrays. Since this is not a main
    issue yet, it was recommended only to allow arrays of characters
    in the current proposal and review the issue when array
    definitions are more tested. Only the main proposal is 
    up for recommendation NOT the appendices on Multi-dimensional
    and Variable Length Arrays.

 4) IMAGE: All agreed to recommend the current proposal i.e.
    with the name 'IMAGE', PCOUNT=0 and GCOUNT=1. It was found
    that this extension 

 5) World-Coordinates: There were general agreement on that a
    firm definition was required even if it did not include all
    non-linear cases.

 6) Any Other Business: A proposal from V.Lipovetsky (Russian 6m) was
    circulated. Many of the features could be encoded using the
    BINTABLE proposal which was not know to him at the time.
    A definition of data sequences in arrays was introduced.

    Compression of FITS data files were discussed. It was unclear
    if the better approach would be to have a special compress
    extension or just compress to total FITS file using standard
    tools. The introduction of hardware compress for several
    devices (e.g. 8mm and DAT) would solve some problems in transport,
    however, the techniques used are not yet standard.

It was agreed that the three proposals listed below were acceptable
in their present form and could be recommended:

    a) Binary Table Extension to FITS, W.D.Cotton and D.Tody,
       (20 September 1991). Note: only the main proposal is
       considered NOT the appendices!

    b) The FITS IMAGE Extension, A Proposal, J.D.Ponz, R.W.Thompson,
       J.R.Munoz (7 February 1992).

    c) Draft Proposal for Blocking of Fixed-block Sequential Media
       and bitstream Devices, P.Grosbol, D.Wells (1990-August-10).

The texts are available through anonymous ftp at ESO, NRAO and GSFC.
Since not all members of the Committee were present the final vote
would be done in June through e-mail. Final testing, wording and
possible clarification will be done through the review by the IAU FITS
Working Group.

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From: pgrosbol at eso.org
Subject: Addendum to Minutes of European FITS Committee 8th Meeting
Date: Tue, 09 Jun 92 17:10:15 +0200

             Addendum to Draft Minutes of 8th Meeting
                                 of
                      European FITS Committee
                       prepared by P.Grosbol
                         ESO, 1992-June-09

Due to an error I had during the editing, point 4) of the minutes
was not complete.  The full text is given below (sorry):

 4) IMAGE: All agreed to recommend the current IMAGE proposal i.e.
    with the name 'IMAGE', PCOUNT=0 and GCOUNT=1. It was found
    that this extension is required to provide an easy way of 
    append other images (e.g. flags, errors, or PSF's) to the 
    prime matrix . Although the BINTABLE extension later may be
    extended with conventions to encode images, such conventions 
    (see Appendices in BINTABLE proposal) are yet neither tested 
    nor finalized. To ensure that the IMAGE extension remains
    simple the values PCOUNT=0 and GCOUNT=1 were recommended.
--

Donald C. Wells             Associate Scientist        dwells at nrao.edu
National Radio Astronomy Observatory                   +1-804-296-0277
520 Edgemont Road                                 Fax= +1-804-296-0278
Charlottesville, Virginia 22903-2475 USA            78:31.1W, 38:02.2N