[ka-Map-users] Improving ka-map speed with non-cached WMS?

Stephen Woodbridge woodbri at swoodbridge.com
Wed Dec 16 22:56:55 EST 2009

Personally, I have switched all my application building over to 
OpenLayers because is has all the functionality of ka-map on the client 
side and will support ka-maps precache script if you want to use it on 
the server-side and you can mix layers in tiles, with a single-tile mode 
which just draws a single large image filling the view port like you are 
requesting. Also OpenLayers has a very active community and is still 
very active on the development side of things.



Bistrais, Bob wrote:
> I'm looking into doing this, and may well be asking for further advice.
> Taking it from another angle- is it possible to bypass or disable
> ka-map's tiling for the image layers?  I don't mean precached vs.
> nocache, what I mean is, is it possible to draw the WMS data directly
> and without breaking it into tiles when ka-map renders it?  I'm asking
> because this seems to be what's slowing it down.  I can draw my WMS
> services in MapServer CGI mode and they're plenty fast.  Likewise, using
> the same WMS services in ArcGIS or other platforms, they draw more
> quickly than with ka-map.
> -----Original Message-----
> From: Stephen Woodbridge [mailto:woodbri at swoodbridge.com] 
> Sent: Monday, December 14, 2009 6:02 PM
> To: Bistrais, Bob
> Cc: ka-map-users at lists.maptools.org
> Subject: Re: [ka-Map-users] Improving ka-map speed with non-cached WMS?
> There may be other or even better ways of dealing with this, but my
> strategy has been convert all the imagery to uncompressed GTIFF data
> using an internal tiled format which is the most efficient for mapserver
> to access. And then to run gdaladdo on top of those. Really large files
> will probably need to be tiled into smaller tiles and then built a
> tileindex to stitch it all back together again. This will give you good
> mapserver performance at the cost of disk space. If you data is getting
> update and you need to remove old imagery and replace it, then use some
> kind of directory structure to help manage that, for example if you have
> a file xxx.sid create a directory xxx_sid and put the tiles in there. 
> then if you need to replace xxx.sid in the future it is easy to remove
> the old tiles and create new ones.
>    -Steve
> Bistrais, Bob wrote:
>> We have our imagery data for the WMS services in three different
>> formats- JP2, SID, and GTIFF.  I've been doing most of my testing with
>> the jp2, since that's statewide orthoimagery.
>> The application is presenting the WMS service in PNG24.
>> A gdalinfo for one of the images gives the following:
>> Driver: JP2ECW/ERMapper JPEG2000
>> Files: C:\naip_07\tiles\augusta_nw.jp2 Size is 5655, 7594 Coordinate 
>> System is:
>> LOCAL_CS["unnamed",
>>     UNIT["unknown",1]]
>> Origin = (429916.000000000000000,4914197.000000000000000)
>> Pixel Size = (1.000000000000000,-1.000000000000000)
>> Corner Coordinates:
>> Upper Left  (  429916.000, 4914197.000) Lower Left  (  429916.000, 
>> 4906603.000) Upper Right (  435571.000, 4914197.000) Lower Right (  
>> 435571.000, 4906603.000)
>> Center      (  432743.500, 4910400.000)
>> Band 1 Block=5655x1 Type=Byte, ColorInterp=Red
>>   Overviews: arbitrary
>> Band 2 Block=5655x1 Type=Byte, ColorInterp=Green
>>   Overviews: arbitrary
>> Band 3 Block=5655x1 Type=Byte, ColorInterp=Blue
>>   Overviews: arbitrary
>> As for the mapfile layer- do you mean the mapfile which consumes the 
>> WMS (part of the ka-map app), or the file which creates the WMS 
>> service?  If you mean the file which consumes the WMS, this is it:
>> #NAIP Orthoimagery
>>   GROUP "NAIP2007_Imagery"
>>   NAME "naip2007"
>>   TYPE raster
>>   CONNECTION "http://myserver/wms/mapserv.exe?map=c:/wms/orthos.map&"
>>     "wms_server_version" "1.1.1"
>>     "wms_format" "image/png"
>>     "wms_title" "NAIP"
>>     "wms_abstract" "NAIP 2007 imagery"
>>     "wms_srs" "EPSG:26919"
>>     "wms_onlineresource" "MaineOrthos-NAIP"
>>     "wms_name" "naip2007,naip10moverview,naip100moverview"
>>     "queryable" "false"
>>     "tile_source" "nocache"
>>     "imageformat" "PNG24"
>>   END
>> END
>> -----Original Message-----
>> From: Stephen Woodbridge [mailto:woodbri at swoodbridge.com]
>> Sent: Thursday, December 10, 2009 3:14 PM
>> To: Bistrais, Bob
>> Cc: ka-map-users at lists.maptools.org
>> Subject: Re: [ka-Map-users] Improving ka-map speed with non-cached
> WMS?
>> Bistrais, Bob wrote:
>>> I have a ka-map application which consumes WMS services, consisting 
>>> of
>>> various imagery layers.  We don't want to precache tiles for the WMS.
>>> We also have precached tiles for vector data in the application.
>>> I don't know if it matters, but the web server uses IIS, not Apache.
>>> Other viewers, such as ArcGIS and Quantum GIS, can consume the same 
>>> WMS services and have much faster draw times than our Ka-Map
>> application.
>>> We would like to see improved draw times for the WMS imagery, again, 
>>> without precaching it.  Can anyone make recommendations or point me 
>>> to
>>> a resource discussing this?
>> Bob,
>> Probably need more information like:
>> What your mapfile LAYER looks like?
>> What format is the raster data in?
>> What does gdalinfo /path/to/a/raster.file look like?
>> and this is really a question about how to increase performance of 
>> raster data from mapserver and might get a better response from that 
>> list.
>> I think there is a page(s) in mapserver docs on how to do this:
>> http://www.google.com/#hl=en&source=hp&q=mapserver+raster+performance
>> -Steve

More information about the ka-Map-users mailing list