OssimSingleImageChain question

classic Classic list List threaded Threaded
2 messages Options
Reply | Threaded
Open this post in threaded view
|

OssimSingleImageChain question

Keller, Greg R.

Hi Ossim-Devs,

 

I have a question about the OssimSingleImageChain. I am using it to load jpg/geom files that are 512x512 and connecting multiple ossimSingleImageChains together with an ossimImageMosaic to get a single output reference.

I am seeing a very large memory footprint for the ossimSingleImageChain objects themselves. (About 5 megabytes per object instance).

 

Right now I am calling open followed by

setAddChainCacheFlag(false);

setAddHistogramFlag(false);

setAddResamplerCacheFlag(false);


and then calling createRenderedChain

Is this memory usage normal? Is there anything that I can do to reduce the memory usage or anything you see that I am doing wrong?

 

Thanks,

Greg Keller

Leidos Inc


------------------------------------------------------------------------------
Slashdot TV.  
Video for Nerds.  Stuff that matters.
http://tv.slashdot.org/
_______________________________________________
www.ossim.org
Ossim-developer mailing list
[hidden email]
https://lists.sourceforge.net/lists/listinfo/ossim-developer
Reply | Threaded
Open this post in threaded view
|

Re: OssimSingleImageChain question

David Burken
Hi Greg,

Two thing I can think of are tile size and cache size.  Usually each object in the chain owns a tile.  The ossimJpegTileSource has a cache to avoid decompressing.  So it actually creates two tiles, one cache  and one to pass on in the getTile.  So depending on your tile size and the amount of tile request on each individual single image chain that may be the issue.  I wouldn't think it would be 5MB though given:   512x512x3x2=1,572,864.   It would be a good idea to save the state of the chain to a keyword list and print out for debug.

The tile size is controlled by the ossim preferences by the "tile_size" keyword.
The application fixed cache is controlled by the "cache_size" keyword.

To see your preferences you can do.
$ ossim_info --config

See:
http://trac.osgeo.org/ossim/browser/trunk/ossim/etc/templates/ossim_preferences_template

Hope that helps,
Dave

On 08/25/2014 05:47 PM, Keller, Greg R. wrote:

Hi Ossim-Devs,

 

I have a question about the OssimSingleImageChain. I am using it to load jpg/geom files that are 512x512 and connecting multiple ossimSingleImageChains together with an ossimImageMosaic to get a single output reference.

I am seeing a very large memory footprint for the ossimSingleImageChain objects themselves. (About 5 megabytes per object instance).

 

Right now I am calling open followed by

setAddChainCacheFlag(false);

setAddHistogramFlag(false);

setAddResamplerCacheFlag(false);


and then calling createRenderedChain

Is this memory usage normal? Is there anything that I can do to reduce the memory usage or anything you see that I am doing wrong?

 

Thanks,

Greg Keller

Leidos Inc



------------------------------------------------------------------------------
Slashdot TV.  
Video for Nerds.  Stuff that matters.
http://tv.slashdot.org/


_______________________________________________
www.ossim.org
Ossim-developer mailing list
[hidden email]
https://lists.sourceforge.net/lists/listinfo/ossim-developer


------------------------------------------------------------------------------
Slashdot TV.  
Video for Nerds.  Stuff that matters.
http://tv.slashdot.org/
_______________________________________________
www.ossim.org
Ossim-developer mailing list
[hidden email]
https://lists.sourceforge.net/lists/listinfo/ossim-developer