Wilbur Crash during Incise Flow.....file size limitations?

[SAHarris]

HI guys,

I am working on a huge world map at print resolution....file is 12000 x 4800 px (32.4mb) 16-bit grayscale .PNG file.

I am working on a toshiba laptop with 3 GB ram + and external hard drive scratch disk of 75GB. It is running Windows Vista 32 bit. I also re-installed the newest version of Wilbur for my system and tried this a second time.

I am able to open the file and view it, however when I begin to do anything with the file (fill basins, incise and flow) it says it is not working, but It is actually using 98% of the CPU, so I know it is still working, then eventually it crashes.

I am assuming that this is a RAM issue. IF so, is there a way I can tell Wilbur to use the external Hard drive as a scratch disk?? I am using this set up in PSCS3 with no issues what so ever.

Please advice if there is an upward file size limit, or if there is a way for me to bypass this issue......

All I need is to get the file incised and a few other things to import back into Photoshop.....

Thanks....

[arsheesh]

This is really a question for Wadronate, but I can tell you from experience that the 32 bit version of Wilbur has difficulty handling files sizes in excess of 4000x4000px (300dpi). Waldronate suggested to me that the 64 bit version could better handle larger files, but I haven't been able to get it to work on my system. One trick you can use with larger files (though perhaps not with the file size you are using) is to crop out the sea. Of course, that assumes you are working with on a map of a landmass surrounded by a body of water; if this is not the case then this technique will not work. If so however, cropping out the sea will reduce the file size. Once you've finished running the land through Wilbur then you can enlarge the canvas of the image back to it's original size in GIMP or PS. OK, I'll stop talking now and wait for Waldronate to come and clear this up better than I can.

Cheers,
-Arsheesh

[waldronate]

Most likely you're encountering an out-of-memory condition. The 32-bit version of the program is pretty strictly limited to about 2GB or memory space, including program space, working buffers and undo space. Wilbur won't try to swap data in memory out to disk on its own; it assumes that its memory needs will all fit into the available process memory space.

12000*4800 is about 58M samples. Wilbur uses 4 bytes per sample for height information, 1 byte for selection, and 4 bytes per color. That's just under 520MB of memory per state. Wilbur will try to allocate that amount of memory again for every action that saves an undo. In addition, it may try to allocate several working buffers during an operation (they would only be 4 bytes per sample per buffer, but that's a whole lot of memory for very large surfaces).

With that size of surface, you'll be butting up against the 1.5GB or so of free memory space available pretty quickly.

The answer to your question about moving a scratch file is that no, you can't do it because Wilbur doesn't have one. The answer to your other question about maximum file size is that you're probably going to find a practical size of 4000x4000 to 6000x6000 samples. If you cut your image dimensions in half (6000x2400) then you will probably be able to comfortably work with the file in the 32-bit edition of Wilbur.

If you were running something like the 64-bit version of Windows 7, then you could use then 64-bit edition of Wilbur, which has the Win64 per-process space of 8TB rather than the 2GB for the 32-bit edition.

One other thing to watch out for with larger surfaces is that incise flow operations can appear to be doing nothing at all for a long time (literally an hour or more). There won't be a user interface for that section due to how Wilbur interacts with the OpenMP libraries that let it do multithreading.

[SAHarris]

Thanks Waldronate!

I appreciated that info...I am looking around to see if I know anyone with a computer that meets those requirements....aka 64bit windows 7 with some serious RAM.....My next computer will be able to do that, but don't have the money together yet....

Thanks for your help and the technical info.