The IAS Viewer is our preferred tool for looking at HiRISE images in full resolution. It provides excellent support for the JP2 file format and the interactive streaming protocol for JP2 which is called JPIP. It is written in Java and installs automatically in a secure “sandbox” on your computer when you visit a link to it. These links are in a section labeled “JP2 Quicklook (IAS Viewer)” on the HiRISE web site; every observation will have that on the right-hand side of the page.

We use the IAS Viewer ourselves in most cases. A prerequisite is having Java installed already on your computer; I’m pretty sure that both Microsoft Vista and Apple’s OS X do that by default, and most older versions of those operating systems do too. You can check by going to java.com and clicking on the “Do I Have Java?” link.

I have tested the IAS Viewer on a 2001-era computer (an iMac DV) with a low-speed wireless connection. Surprisingly, it worked about as good as on our work machines (dual or quad-core Macs with gigs of memory and ultra-fast Ethernet connections to nearby servers). With much older PC’s or via dial-up it may not be usable, I expect. But the bottom line is, you do not need to have the latest and greatest in computing technology to fill your screen with a steady source of high-res HiRISE pixels.

Early in the mission, our partners at NASA Ames put together a site using a Flash applet called Zoomify. They still maintain this site; however, it takes time and effort for them to keep up with our releases. Zoomify uses “tile pyramids”, or multiple copies of image data at each zoom resolution. So not only must the data be transferred, it must then be rendered into many tiles, occupying slightly more space than the original data. For that reason, they convert to JPEG, which eliminates some of the highest resolution information. Still, it may be faster because the lower resolutions are pre-rendered and the highest resolution has been decreased. Flash, like the IAS Viewer, is supported on Windows, Mac, and (x86 flavors of) Linux.

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The HiRISE project has developed a fairly significant amount of software. I’ve been privileged to play a part in that development, which continues even as we get deeper into the primary mission. So, rather than space science or operations, this post will discuss one of the nittier, grittier aspects of our work.

The processing pipelines have been introduced in earlier entries. Thanks to the efforts of HiRISE developers (mostly before my time with the project) these have provided a very solid foundation for our automated ground data system. There has been very little need for trouble-shooting or fine-tuning of the core software.

One issue that did come up earlier in PSP however was a strange failure that happened periodically, though not predictably. If you are a programmer, there is nothing so dreadful as a bizarre, non-repeatable bug… not counting Monday morning meetings, of course.

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Here we are over two weeks into PSP, and we haven’t even finished releasing our TRA images!

Actually, today we got 31 TRA images out the door, just about completing that set. In addition, the previous 32 grayscale images have been reprocessed with our improved geometry—no more jagged edges on the reprojected “Red Mosaics”.

Furthermore, the full-res images are now available as lossless JPEG-2000 (JP2) files. At HiROC we are using the ExpressView application from a company called LizardTech… a subsidiary of some Japanese company (that has no affiliation to us FWIW).

ExpressView is available for Mac and Windows. Their download page describes it only as a browser plug-in, but the installer contains an application as well.

ExpressView provides progressive rendering (though you still have to have the entire file first—we are considering moving to a streaming model using the JPIP protocol but there are even fewer clients available). It should also reduce the amount of memory (RAM) needed to view our largest images.

There are a few options available to Linux users, but nothing we have tried is as fast or as feature-rich. In any case, let us know what works or doesn’t work for you.

All of these images are available at the usual location.

A system for streamlining the process of editing captions, highlighting cut-out areas and pushing out web pages is in the works. We will get caught up.

In the meantime, look for the first set of PSP releases by this time next week.

P.S. Happy Thanksgiving.