Meeting Agenda
1. Call to Order
2. Approval of Agenda
3. Approval of Minutes of previous mtg
4. IEEE Patent Policy
5. Discussion of Draft Standard
6. Other Business
7. Future Meetings
8. Adjourn
Minutes of SAR Metadata Std Working Group Meeting
July 30, 2020
1. Call to order
attendees:
Leland Pierce
Wade Schwartzkopf
Marc Trachy
Chuck Heazel
Mike Stewart
nathan Bombaci
Vanessa Lalitte
we have a quorum
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2. Approval of agenda
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Marc moved, Wade seconded, no discussion, no opposition
approved.
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3. Approval of minutes of previous meeting
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Marc moved, Mike seconded, no discussion, no opposition
approved.
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4. IEEE Patent and Copyright Policy
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1. slides 1-4 were shown and discussed by the chair
2. Chair provided an opportunity for participants to identify patent
claim(s)/patent application claim(s) and/or the holder of patent
claim(s)/patent application claim(s) of which the participant is
personally aware and that may be essential for the use of that
standard.
Wade said he would look into what the status was of the NGA copyright transfer process for SICD.
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5. Discussion of current draft standard
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Discussion on Marc Trachy’s document giving ideas for changes to make
in SICD for this standard.
1. Replace /SICD/ImageCreation with a lineage
current SICD image-creation metadata is limited, if change to
lineage can put more info there for humans.
need exact details.
chuck has presented some ideas on this already.
chcuk mentioned that error-popagation could also be added.
Leland: perhaps we need to survey other SAR formats for what they
include.
2. Remove AMP8I_PHS8I (likely PixelType won’t appear in the IEEE
version anyway)
Wade has seen it used, so wants to keep it.
the ISO range-type could be used instead to describe the structure
of the data for each pixel.
3. /SICD/ImageData/ValidData:
Make required and to include no zero filled pixels,
(may discard some valid pixels for simplification)
check says that there is no ISO concept for this.
4. /SICD/ImageData/SCPPixel: Allow to be non-integer
make it real-valued
center of pixel in SICD
need to look at implications to other metadata that uses line and
column values
the PHD std does this
5. /SICD/GeoData/EarthModel: Replace with an ITRF version?
currently required to be wgs84.
wgs84 is not precise enough in its definition for some applications
replacing with a specific ITRF would be better
6. /SICD/GeoData/GeoInfo: Remove
this is basically a list of “lat, lon, feature description”
largely NGA-specific
everyone agreed to remove it.
7. /SICD/Grid/ImagePlane: Remove
an enumeration: SLANT, GROUND, other
historically has been poorly-populated: inaccurate
however, may still be useful for some applications
8. /SICD/Grid/Type: Document which ones can go with with image
formation algorithms
info in V3. perhpas include in our std?
9. /SICD/Grid/TimeCOAPoly: Document more precise definition of center
of aperture time
OK
10. /SICD/Grid/*/ImpRespWid: Remove
most other stds have this, but not useful
maybe just add more docs on how to use it?
code exists on github.
11. /SICD/Grid/*/Sgn: Remove (force -1, producers must conjugate if they would have had +1)
SICD has 2: 1 for row, 1 for col
only 1 would be better, none even better
all other phases need to be conjugated if need to change it
some producers screwed this up
need more docs
12. /SICD/Grid/*/KCtr: Either rename to KOrigin (my preference) and force producers to make it constant across the image or make it variable across the image.
possible to make constant
currently specified as a constant, but it actually varies across
the image
need to describe the variation across the image
cosmo-skymed/INCA: KCtr is cont across the image,
but delta-KCOA is not, in spotlight mode
PFA with slant deskew
perhaps rename to KOrigin so less confusing, or KZero. Give good defn.
13. /SICD/Grid/*/DeltaK1 /SICD/Grid/*/DeltaK2: Remove
limits of spectral support of image in each direction, or nyquist,
whichever is smaller
not helpful, especially if doing part of an image
calculating by yourself is best
14. /SICD/Grid/*/DeltaKCOAPoly: Make required
everyone agreed to make it required.
can be zero, but must be specified
15. /SICD/Grid/*/WgtFunct and /SICD/Grid/*/WgtType:
Replace with required consolidated structure where WindowName
and WgtFunct are required or force uniform weighting.
change to have new class, including:
WgtFunct, WindowName, WtFunc
and make all required
16. Add slowtime and frequency 4d grid
could take an hour to discuss
all possible if know image formation algo.
docs do not describe how to do it.
have provider do it using their image-formation-algo
general agreement, but need more details.
17. /SICD/Timeline/CollectStart: Change to reference time
everyone agreed
18. /SICD/Timeline/CollectDuration: Remove
everyone agreed
19. /SICD/IPP: Make required?
difficult to generate from some providers
need better docs so it will be populated correctly
general agreement
20. /SICD/Antenna/TwoWay: Remove
agreed. just use 2 1-way’s
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6. Other business?
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none
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7. Next meeting
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the group wanted to have the next meeting in 2 weeks, at 11am.
Our next meeting will be on :
Thursday, August 13, 11AM Eastern time
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8. Adjourn
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Marc motioned, Wade seconded. no opposition. passed