Man, oh man...watched each several times, never gets old. Thanks, Doug!

Truly excellent work Doug, I've toured the Pathfinder site a dozen or so times now, thanks to you!

Now, if we can just get you and James Cameron in the same room, maybe, just maybe, the two of you can bring "Red Mars" to the big screen...!

Very nice work!

This was raised over in the Opportunity distant vistas thread, but I think this is probably the better home for it.

After helping Doug make the Pathfinder DEM, we were trying to figure out how well it matched up with the panorama from on the ground (suspiciously well!). So using the same method as in the other thread, here's my attempt at trying to show the distant features that show up for something about 1.5 m off the deck at Pathfinder's location.

Here's a hillshade basemap of the DEM, with a colour map overlain. I had to stretch the colour to show off the subtle topography at Pathfinder, hence the cut-off at big crater. You can also see the only error in the whole DEM near the top. The red dot is Pathfinder.
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And here's basically the visibility of that DEM from Pathfinder. Same colours as before - green is visible, red is not. Twin peaks and big crater show up quite nicely.
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Pete

What a fantastic and useful technique Pete! The work you guys are doing is amazing!

What was amazing was that just the very tip of North Knob was visible - and bingo, the Viewshed called it out perfectly.

just out of interest, here are a few quick views of the pathfinder area ("twin peaks" and the area immediately surroundig the lander) rendered using the single-image shape-from-shading (SFS) method described in the other thread ...
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although the SFS based DEMs are probably far less accurate overall than the near perfectly precise official stereo/altimeter based HiRISE DEMs, it is still amazes myself how much 3D detail can be squeezed out from a single image already...

You used the annotated one

I'm having some problems with the DTM .IMG files from the HiRISE site. It seems like the same (or similar) problem I was having back in page 4 of this thread.

I'm using the latest version of FWTools (2.4.7) and I can open up the .IMG in OpenEV. But I can't convert it to a .jpg, .bmp, .gif, or a .png file. It just says "unable to create output file...". When I try converting it to a .jp2 or a .tif file, it appears to work, but when I open the exported file into photoshop, it's completely black in the .tif file and completely grey in the .jp2.

Does anyone have any idea what's going on? Is there something I need to do to it before exporting it to another file format?

Use Bjorn's latest version of img2png - it'll turn it into a PNG for you.

Thank you djellison, that worked.

Now to see if I can do anything interesting with them in 3dsmax

Seems like the video's are still entrancing new fans, just noticed Gizmodo picked it up via Twitter from Roger Ebert.

Edited - I just noticed Emily's comment on the Discovery article regarding the attribution of the video and corrected my own mis-attribution. Hangs head in shame.

Yup - it's Adrians awesome work. Mine don't look anywhere near as good, and mine take minutes per frame, rather than 30 frames per second.

I've emailed the Gizmodo writer, commented at Discover, hopefully they'll get the message and correct it. Adrian is the one who deserves the credit for this, not me!!

New DEMs have been posted on the HiRISE website here.
Maybe some of the imaging wizards on this forum can use them to create flyovers, oblique views... I wish I could try it myself, but I don't have the tools to do it, nor the time to learn how to do it (there's a thing called "work" that gets in the way). I know everybody here has his own occupations, so I understand that it's not possible to fully exploit all those goodies.

Hi all, I've finally had enough free time to do some more animations based on the HiRISE DTMs. I hope you like them.

West Holden crater
Zumba crater
Dunes in Herchel crater
Dune Avalanche

Just totally awesome, especially when viewed in full-screen mode!

Absolutely. Freaking. Spectacular.

Thank you!!!!!!!!!!

Meh.

Mars3D:

Finally I downloaded your animations (HD) and with proper music, it's really ecstasy!

Thanks for kind words.

I have uploaded some more videos, these ones are in 1080p format.

They were created from DTM's I've used in previous animations but the paths are different.
Mojave
Athabasca
Dune Avalanche

You'll need to manually select 1080p for the best quality as it usually defaults to 360p.

- Adrian

Absolutely amazing. I love your animations. I do have a question if you don't mind. How do you handle the large .25m images and in real time no less? Do you chop them up into more manageable pieces? Or do you just have a really powerful computer/graphics card? I've been using 3dsmax and it really doesn't like large images, so I have to chop mine up into small bits, which can be a bit of a pain. I'm just wondering if you have a better technique or solution.

Thanks.

Hi JRA,
I have 4GB of ram (only 3GB is usable because I'm running a 32bit OS) The maximum image size I have been able to load into system memory is 32768x49152. Because its greyscale it uses 32768x49152x1 bytes which is 1.6GB. The image is then broken into tiles in memory and a cache of visible tiles are stored on the graphics card, so although I have a graphics card with 1.5Gb of RAM I think 512MB of video RAM would work ok to.

Some of the dataset images are bigger than what I can load into system memory e.g. Mojave, so I have to crop them. A 64bit OS with 6GB of RAM would allow me to not crop any of the datasets and run at the maximum resolution.

I am using a dual core CPU @ 1.8Ghz, CPU speed is not a limiting factor and mid range GPUs can handle the number of polygons I'm rendering. The biggest issue is the high system memory requirement.

I don't know 3dsmax so I cant give you any advice on that.

Hey, thanks for the reply and information. I think I'll have to stick to chopping them up into bite sized pieces for now then.

These are all great visualizations of the HiRISE elevation data, Doug your flyovers are simply superior. I am still crashing my spacecraft through the surface or veering off into the vast whiteness of space. I also think your layover here is outta this world, literally.

I wanted to visualize how the Gale Crater (msl study site) surface projects itself in terms of different sensors, as well as between the 10 adjacent HiRISE dtms listed on the map. A two-framed “flashing” movie here is an example of feature dislocation at the edge of the orthographic images. The map below projects those differences at 50-meter breaks spanning the 10 HiRISE dtm extent. The difference at the edges (featured in red) is most apparent in the Northern portion of the image. The hilly terrain to the south values are offset slightly compared to the Northern portion, but still visibly offset by some tens of meters in places. This offset affects the mosaic, and every model I run afterward, which is in conflict with my longing for order, especially in the overlapping regions of the map at larger extents. I have a couple ideas I may try but my mars time is slipping away rapidly to studies of a more earthly nature.... If anyone has experience geo-referencing or creating orthos I would greatly appreciate your comments.
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Any HiRISE DTM (and I assume HRSC DTM ) gets matched to the reference MOLA data. In same cases, there might only be one or two MOLA points within an entire DTM with which to do that.

The uncertainty of MOLA, the sparsity of its data compared to the HiRISE or HRSC footprint, the size of a MOLA footprint, and os on and so forth - this results in the differences between neigbouring DTMs.

It's a non-trivial task to remove those differences - one which I know some developers here on lab have tried to solve using a gradient domain solution that took several months.

RRussman, each DTM is ortho rectified an as such they are projected on a flat plane but each DTM is projected on a different plane so at the edges the planes exhibit the largest co-registration error. You would need to re-project all DTMs on a common plane but besides being non-trivial, the map you obtain is not really "ortho" anymore as you would have significant distortions. The other thing you could do is to project each DTM on the spheroid and then do a cylindrical projection. There's no good solution and what I do is to just work on one DTM at a time (currently still on PSP_010573_1755).

Paolo

One lesson to take from this is that DEMs and associated orthophotos look beautiful but are not gospel. You have to treat them with a bit of suspicion.

Phil

Doug, I’m pretty sure everything is matched to MOLA after 2000, but as you point out, the sampling is sparse even along track. By sparse I mean there are 48,211 mola points (PEDR) over several tracks/orbits in the map extent, and yes, some dtms are far more populated than others are. The HRSC and HiRise products are continuous data sets with much finer resolution. An excerpt from the literature on the resolution mismatch:

“Because of the low horizontal resolution of the MOLA data set compared to HiRISE images, vertical accuracy will likely be governed by the difference between localized topographic features and the broader-scale relief as measured by the altimetry, and may be several meters. The resolution mismatch between the two data sets is likely to make direct use of MOLA for horizontal control almost impossible. Our approach is to control lower-resolution images to a shaded relief product generated from MOLA data gridded at 1/256 or 231 m/pixel, then to transfer control from these images to the high-resolution stereopair.” (McKewen, etal, 2007) (from Wiley/JGR, access required for full text)

The discontinuity is most noticeable in the northern portion of the map with the DTEEC_010573_1755_010639_1755_U01 appearing offset more, relative to the adjacent overlapping regions, as well as the general flow of the collective model at multi-product extents. It might simply be that this model received less rigorous processing to the north and away from the msl region of interest.
“Since editing is extremely time-consuming, it is usually done on easily corrected errors and in the areas of most interest to the researcher.” (From the About DTMs page)

Paolo, I appreciate your suggestions and will experiment with re-projecting the dtms. I have experimented with re-geo-referencing the orthos (3rd order polynomial RMS:~0.7). The distortions were minimal, but as you mentioned, they lose their distinct relationship to the dtm and coordinate system, not to mention time consuming, tedious work. It makes your solution sound very appealing.

Phil, I am suspicious of every data set I open, especially my own