McIDAS-V Support Forums

Hi, we're having a problem with GeoTIFF files which have the Model Type tag set to Projected (1).

The problem is that in the Field Selector tab of the Data Explorer in McIDAS-V (1.7u1), the only Display option shown is Omni Control - the normal Image Display options aren't shown.

GeoTIFF files with Model Type set to Geographic (2) all work fine and can be opened in an Image Display.

This is causing us a particular problem with certain GeoTIFF files produced by the NASA DRL IPOPP software which use a Stereographic projection by default.

We altered some settings in IPOPP to generate those files using the Geographic model type and this allowed them to be opened in an Image Display.

However we need to be able to use the Stereographic projection for polar regions, where Geographic isn't suitable.

I found previous posts about problems with non-rectilinear coordinate systems when using the Flat File data source, but please can someone confirm if there are similar limitations for GeoTIFF files. And if so, are there any plans to support projected GeoTIFF files in the future?

Best Regards,

Chris Wright
Dartcom

Hi Chris,

Thanks for reporting and explaining this issue. There is an existing request to expand the projection types supported with GeoTIFF files. It's written up as McIDAS-V Inquiry 1835. I will add a cross-reference in it to this forum post so the programmer is aware of your particular request.

Can you please post a sample file (or files) to our anonymous ftp? Here are instructions:

ftp ftp.ssec.wisc.edu
user: anonymous
password: your_email_address
bin
cd pub/incoming
put filename
bye

Once you post the file(s), please let us know the name(s) so we can add it/them to our testing dataset.

Thank you,
Barry

Hi Sir

I know this..
The best way to handle this is to get
the ncj geotiff iosp:
https://github.com/USGS-CIDA/geotiff-iosp

I posted it long time back to ncj community.
They told it may get integrated into the ncj branch in due course of time. But it never happened.
If you can post that sample file. I can try to atleast ingest it into mcv.

Regards
Ghansham

See this thread:

https://www.unidata.ucar.edu/support/he ... 02340.html

Hi all

Sample program showing how to read projected geotiff using geotiff iosp for ncj.
Output of program is also shown.

The best way could be to create an "Under Development->DataSource" before ncj community officially adopts it

Ghansham

Thanks for your replies Barry and Ghansham.

A sample GeoTIFF file containing channel 4 of an AHRPT image transformed to a Stereographic projection can be downloaded from here:

ftp://ftp.dartcom.co.uk/pub/geotiff/DartcomGeoTIFF.tif

And this is what it looks like when loaded into Global Mapper:

I've also uploaded the following files to the pub/incoming folder on ftp.ssec.wisc.edu:

DartcomGeoTIFF.tif
MODSHARPTCOLOR_roi1_18302105308.tif

The second file is a BlueMarble MODIS image generated by the NASA DRL IPOPP software using the Stereographic projection.

Regarding the NCJ GeoTIFF IOSP, I'm not clear how I could add this to McIDAS-V - any pointers Ghansham?

Best Regards,
Chris

The quickfix can be I can create a plugin and send you that. It should work for you.

Many thanks Ghansham, if you can give me a link to download the plugin I'll give it a try.

Chris

Hi All

I will try to generate a plugin and upload it on this thread itself. Give me a couple of days.
Ghansham

Thanks Ghansham, there's no hurry. Will await news in due course.

Chris