[McIDAS #TEU-219455]: topo map

Hi Kwan,

re:
> You were right.  I did not use McIDAS to display the images.  I used GEMPAK.

That would go a long way towards explaining the discrepancy in
the rendition of the colors in the displays.  GEMPAK does not support
display of more than ** I think ** 90 color levels, and its way of
mapping to those levels is "interesting".

re:
> This seemingly simple image remap still baffles me.  Did you use the EB
> command to stretch the colors of the remapped image?

I used EB on two of the images to manipulate the gray scale so
that the Great Lakes area was more easily seen.  In the last set
I sent, I used the TOPO.ET enhancement directly, meaning I did
not do any stretching.

re:
> To dig a little deeper, I ran IMGLIST on the two images.
> 
> imglist.k TOPO/NEW FORM=ALL
> Image file directory listing for:TOPO/NEW
> Pos Satellite/         Date       Time      Center      Res (km)
> Image_Size
> sensor                                 Lat  Lon    Lat   Lon
> --- -------------  ------------  --------  ---- ----  ----- -----
> ------------
> 1  GOES-7 IR      1 JAN 07001  00:00:00    39   99
> Band: 5    No Information Available                  5.28  5.28   762 x
> 1056
> proj:    0 created: 2014270  50754  memo: GINI:: Sat 10  SecID  1
> ChID  5
> type:PRD      cal type:BRIT
> offsets:  data=    1280 navigation=  256 calibration=  768
> auxiliary=    0
> doc length:   0   cal length:   0   lev length:   0 PREFIX=   0
> valcod:          0 zcor:  0 avg-smp: N
> start yyddd: 2007001  start time:     0  start scan:    0
> lcor:    1  ecor:     1  bytes per pixel: 1  ss: 33
> Resolution Factors (base=1):   Line=    5.3   Element=    5.3
> 
> *I had to use RES=6 to make the resolution of the destination file similar
> to that of the original as you suggested.*

Yup, I did also.

re:
> imgremap.k TOPO/NEW MYDATA/IMAGES.3050 PRO=PS X 97 SSI=ALL SSIZE=ALL
> SIZE=ALL RES=6
> 
> imglist.k MYDATA/IMAGES.3050 FORM=ALL
> Image file directory listing for:MYDATA/IMAGES
> Pos Satellite/         Date       Time      Center      Res (km)
> Image_Size
> sensor                                 Lat  Lon    Lat   Lon
> --- -------------  ------------  --------  ---- ----  ----- -----
> ------------
> 3050  GOES-7 IR      1 JAN 07001  00:00:00    39   99
> Band: 5    No Information Available                  5.24  5.24   908 x
> 1160
> proj:    0 created: 2014273  55929  memo: GINI:: Sat 10  SecID  1
> ChID  5
> type:PRD      cal type:BRIT
> offsets:  data=    1280 navigation=  256 calibration=  768
> auxiliary=    0
> doc length:   0   cal length:   0   lev length:   0 PREFIX=   0
> valcod:          0 zcor:  0 avg-smp: N
> start yyddd: 2007001  start time:     0  start scan:    0
> lcor:  489  ecor:  9392  bytes per pixel: 1  ss: 33
> Resolution Factors (base=1):   Line=    5.0   Element=    5.0
> imglist.k: done
> 
> *I had to run this EB command to stretch the color map of the destination.*
> 
> eb.k 0 10 0 255
> 
> So for some reason, the colors were remapped to only a small fraction of
> the total available color bins in the destination, which I don't quite
> understand.  Is this what you have as well?

I did not do any stretching.

re:
> I am attaching GIF files of the topo maps made using McIDAS.

OK.  Apparently you used EB to stretch the values in topo-test-97.gif.

Again, I used no stretch for the displays of the original and IMGREMAPped
displays that I sent previously.  I simply loaded the images and
specified use of the TOPO.ET enhancement.  Something like:

SF 1; ERASE F; IMGDISP TEST/TOPO EU=TOPO REFRESH='EG;MAP FILE=OUTVHPOL'
SF 2; ERASE F; IMGDISP MYDATA/IMAGES.3050 EU=TOPO REFRESH='EG;MAP FILE=OUTVHPOL'

Cheers,

Tom
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Ticket Details
===================
Ticket ID: TEU-219455
Department: Support McIDAS
Priority: Normal
Status: Closed