NASA has provided some hi resolution image of Digital Elevation Models from Mars. An example can be seen here:
http://hirise.lpl.arizona.edu/dtm/dtm.php?ID=ESP_025277_2275 [hirise.lpl.arizona.edu]

The file I'm interested in is the big 448.1 MB file on the top left of this page.

I can't find anything that will open this file.

I have been told that some of the images they have on their website are 16, but this one is 32 bit. The dimensions are given in the header, so I tried to open it in “raw” format in Photoshop, using 5064 as the size of the header. I got something that looks a little like what I think it should look like, but it is clearly not right, since the header says the file is 32bit and Photoshop will only open a 16bit image.

Is there a way to open a “raw” image in Houdini so I can save it out as a .rat file?

Dave

davedjohnson
NASA has provided some hi resolution image of Digital Elevation Models from Mars. An example can be seen here:
http://hirise.lpl.arizona.edu/dtm/dtm.php?ID=ESP_025277_2275 [hirise.lpl.arizona.edu]

The file I'm interested in is the big 448.1 MB file on the top left of this page.

I can't find anything that will open this file.

I have been told that some of the images they have on their website are 16, but this one is 32 bit. The dimensions are given in the header, so I tried to open it in “raw” format in Photoshop, using 5064 as the size of the header. I got something that looks a little like what I think it should look like, but it is clearly not right, since the header says the file is 32bit and Photoshop will only open a 16bit image.

Is there a way to open a “raw” image in Houdini so I can save it out as a .rat file?

Dave

It seems that these images are stored in PDS format:
http://www.fileformat.info/format/pds/egff.htm [fileformat.info]

The file seems to be a 1 channel file at 15702x7134 pixels, stored as 32-bit floats. Which is about 450MB of data – which seems about right.

I'm not sure how to get this into Houdini though – not without writing code – you might be able to use Python, though I can't think how at the moment.

Adding a custom format is documented http://www.sidefx.com/docs/hdk12.5/hdk_image_extend.html [sidefx.com] and I believe there's a sample that loads in raw data which you might be able to hack.

Thanks Mark. I was really hoping someone else had tackled this. But since it doesn't seem like they have, I'll take a whack at it.

If I get it working, I'll pass it on.

Dave

There are different flavours of PDS .img files around, but in the past I have been able to work with some of them in Globalmapper. That thing is also nice to do reprojections of data.

It might be overkill for what you need though.