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>From: "Mekonnen Gebremichael" <address@hidden> >Organization: Pratt School of Engineering, Duke University >Keywords: 200504201601.j3KG1gv2005753 McIDAS access Hi Mekonnen, >Thanks for your help! No worries. >The following command seemed to work. I guess the problem earlier was I >mentioned the entire file name. Anyway, I have attached the data file. > >DSSERVE ADD TEST/IMAGES AREA DIRFILE=/mek11/sagres_home/GOESdata/* "Test GOES >IR image OK, the problem was that the file name had two periods ('.') in it. I created a dataset including the file you sent to test the image's integrity as follows: <as 'mcidas'> cd ~mcidas/workdata mkdir globir cd globir cp ~support/globir.02182.0015 . mcenv -f 1@700x1200 dsserve.k ADD GLOBIR/AREA AREA DIRFILE=/home/mcidas/workdata/globir/globir.\* \"Global IR composte images I then tested the image using IMGLIST: imglist.k GLOBIR/AREA.1 FORM=ALL Image file directory listing for:GLOBIR/AREA Pos Satellite/ Date Time Center Res (km) Image_Size sensor Lat Lon Lat Lon --- ------------- ------------ -------- ---- ---- ----- ----- ------------ 1 G-8 IMG 1 JUL 02182 00:15:00 5 110 Band: 4 No Information Available 13.93 13.93 1310 x 2852 proj: 0 created: 2002182 10838 memo: RT MSAT MA type:VISR cal type:BRIT offsets: data= 768 navigation= 256 calibration= 0 auxiliary= 0 doc length: 0 cal length: 0 lev length: 0 PREFIX= 0 valcod: 0 zcor: 0 avg-smp: N start yyddd: 2001353 start time:193000 start scan: 2500 lcor: 272 ecor: -9964 bytes per pixel: 1 ss: 70 Resolution Factors (base=1): Line= 14.0 Element= 14.0 imglist.k: done I see that the image size is 1310x2852 and that this accounts for the file size: 1310x2852 = 3736120 When you add the size of the image header and audit comments, the size is the same. So, the README file's suggestion that there were multiple images per file was incorrect. Furthermore, I note that the image is indeed single banded. When an image only contains a single band, you do not have to include the BAND= keyword in McIDAS commands that do something (e.g., list, display, etc.) the iamge. The next thing I did was load the image into the single frame I created in the 'mcenv' invocation and create a GIF out of it: imgdisp.k GLOBIR/AREA.1 MAG=-2 map.k SAT frmsave.k 1 mekonnen.gif The results of this can be seen at: http://www.unidata.ucar.edu/content/staff/tom/gifs/mekonnen.gif As you will notice, the image is black. To verify that the image you sent has no data in it, I used the IMGPROBE command: imgprobe.k LIST BOX DAT=GLOBIR/AREA.1 MODE=N LATLON=5 110 PLACE=C SIZE=600 600 The listing from this showed only zero for brightnesses. It would seem, therefore, that this image has no data in it. >Some more follow-up questions... > >(1) Upon executing this command: >IMGDISP TEST/IMAGES.1 BAND=4 >I found the following error message: "IMGDISP: stretch table specified in >SU= does not exist on server" >QUESTION: how to overcome this problem? I did not get this message. I have seen the message in the past, and I believe that it indicates a problem with the McIDAS build on your machine. Please try the following to see if you can display images from a remote ADDE server: <as 'mcidas'> ** before starting your McIDAS session ** setenv MCCOMPRESS GZIP <- assumes that you have port 112 access through your firewall mcidas <- start a McIDAS session DATALOC ADD RTIMAGES atm.geo.nsf.gov <- point at an ADDE server on atm.geo.nsf.gov for the dataset whose group name is RTIMAGES DSINFO IMAGE RTIMAGES <- see what descriptors are in RTIMAGES Your listing should be: Dataset Names of Type: IMAGE in Group: RTIMAGES Name NumPos Content ------------ ------ -------------------------------------- ANTARCTIC 10 Antarctic IR Composite EDFLOATER-I 10 Educational Floater EDFLOATER-II 10 Educational Floater II GE-39 10 GOES-East 3.9 um IR GE-CO2 10 GOES-East 13.0 um IR GE-IR 10 GOES-East North America IR GE-IRTOPO 10 GOES-East IR/TOPO Composite GE-VIS 10 GOES-East North America VIS GE-VISTOPO 10 GOES-East VIS/TOPO Composite GE-WV 10 GOES-East North America H2O GEW-IR 10 GOES-East/West IR Composite GEW-IRTOPO 10 GOES-East/West IR/TOPO Composite GEW-VIS 10 GOES-East/West VIS Composite GEW-VISTOPO 10 GOES-East/West VIS/TOPO Composite GEW-WV 10 GOES-East/West H2O Composite GW-12 10 GOES-West 12.0 um IR GW-39 10 GOES-West 3.9 um IR GW-IR 10 GOES-West Western US IR GW-IRTOPO 10 GOES-West IR/TOPO Composite GW-VIS 10 GOES-West Western US VIS GW-VISTOPO 10 GOES-West VIS/TOPO Composite GW-WV 10 GOES-West Western US H2O MDR 10 Manually Digitized Radar MDRTOPO 10 MDR/TOPO Composite MOLL-IR 10 Mollweide Composite IR MOLL-IRTOPO 10 Mollweide IR/TOPO Composite MOLL-WV 10 Mollweide Composite H2O RESFLOATER 10 Research Floater DSINFO -- done Next, list out the images in the RTIMAGES dataset: IMGLIST RTIMAGES/GE-IR.ALL This listing should look like: Image file directory listing for:RTIMAGES/GE-IR Pos Satellite/ Date Time Center Band(s) sensor Lat Lon --- ------------- ------------ -------- ---- ---- ------------ 1 G-12 IMG 14 MAY 05134 17:45:00 0 72 4 2 G-12 IMG 14 MAY 05134 18:15:00 0 72 4 3 G-12 IMG 14 MAY 05134 18:45:00 0 72 4 4 G-12 IMG 14 MAY 05134 19:15:00 0 72 4 5 G-12 IMG 14 MAY 05134 19:45:00 0 72 4 6 G-12 IMG 14 MAY 05134 20:15:00 0 72 4 7 G-12 IMG 14 MAY 05134 20:45:00 0 72 4 8 G-12 IMG 14 MAY 05134 16:15:00 0 72 4 9 G-12 IMG 14 MAY 05134 16:45:00 0 72 4 10 G-12 IMG 14 MAY 05134 17:15:00 0 72 4 imglist.k: done Now, display the most recent image in the set: IMGDISP RTIMAGES/GE-IR <- if the position number is not specified, the most recent image will be displayed. Does this work? If not, do you get the same message about a stretch tabke not existing on the server? If yes, there is a problem with your build. Before being able to move on to the 2) will need to figure out exactly why your build is misbehaving. I could login and take a look if you would like. In order to do this I would need login as your 'mcidas' user. (2) I would like to produce an ascii file that contains the subset of this image over the US, but it is not clear from the Learning Guide how to do this. I would appreciate your insight into this. The steps I would use are: - create an output dataset of type AREA into which you can wite images. I would use the default MYDATA/IMAGES dataset since there is a McIDAS BATCH file that will create the dataset for you: BATCH MYDATA.BAT This will create a dataset with group name MYDATA with 4 descriptors: MYDATA/IMAGES MYDATA/GRIDS MYDATA/PTSRCS MYDATA/TOPO You will be interested in using the MYDATA/IMAGES dataset. - create a new image that contains the coverage you want using IMGCOPY. Here is one example of how to do this: IMGCOPY TEST/IMAGES.1 MYDATA/IMAGES.3000 LATLON=30 100 SIZE=600 800 This will result in the extraction of a sector of 600 lines by 800 elements centered on 30N and 100W. The new sector will be written into AREA3000. AREA3000 should be located in your ~mcidas/workdata directory. You will need to adjust the LATLON= center Latitude and Longitude to what you want and the SIZE= to the size you want to get the coverage you desire. - write the ASCII values from the newly created image sector out to disk files using AXFORM. Here is an example: AXFORM 3000 mekonnen FTYPE=ASC This will result in the creation of the files mekonnen.* in the McIDAS working directory which will be ~mcidas/workdata if you are doing all of this as the user 'mcidas'. Please read through the online help for the various commands listed above to learn more about how to use them: HELP BATCH HELP IMGCOPY HELP AXFORM >Thank you, No worries. >p.s. feel free to post this and all other transactions on the online >tracking. OK, thanks. This will be useful for users in the future. Cheers, Tom -- NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.