Hey Steven, if you're use is just the most compact raster source then I think a lossless compression format like mrsid / ecw / jpg2000 may serve you a lot better. MBTiles certainly is an improvement over a bunch of tiles on disk, as it cuts out the disk blocks. But that's about the only gain you get afaik, while the lossless formats actually do get some serious compression.
A little searching on the web lead to this: 'Now for the kicker - size and number of files: MrSID - 80.4 MBs and 2 files; JPG - 21.5 MBs and 3 files; JPG2000 - 4.5 MBs and 3 files; GeoTIFF 24-bits - 121.8 MBs and 1 file; GeoTIFF 8-bit - 10.4 MBs and 1 file. Clearly, the JPG2000 packs the greatest image bang for your MBs.' >From >http://www.evs-islands.com/2008/08/comparison-mrsid-jpg-jpg2000-geotiff-24.html A word of warning with H2 - I made a similar recommendation to your architecture and had someone get burned with data corruption. This was a couple years ago, so it may be better now, but it's tough if anything goes wrong with H2 because there's not lots of tools to get in and diagnose and do backups and the like. Note also that GWC can support WMS directly, by under/over sampling tiles to combine in to the image requested. It can't reproject, but should allow client access. One big question with MBTiles in GeoServer is if it should be a coverage format, or just read direct by GeoWebCache. Recently I convinced myself of the latter. You could do either, but I think doing it in a coverage format breaks some expectations. It works great if the MBTiles are just pure raster data. But if it had vector data go in to it at all then sticking that through a WMS is likely going to make things look crappy, as you'll be sampling and projecting rasterized vectors. The other thing is the UTFGrid interaction stuff, which would be entirely lost if you do a coverage reader, but could be incorporated in GWC. So that if someone made an MBTiles file with utfgrids they could work. And just in general doing it in GWC I feel sets the expectation more properly, that it's tiles. I believe MBTiles should be thought of as more an interactive display format. It's like the modern version of a printed map - something a designer composes to be exactly as they want. Treating it as a raster datastore I think only works unless you're just doing pure raster data in it. But it's not a great format for pure raster data, because it only has one projection, one tile size, etc. I think there is a need for a tile format for mobile devices, but MBTiles would need to evolve a bit to meet that. But then it risks sacrificing its simplicity. On Tue, Jan 31, 2012 at 8:08 AM, Steven Siebert <steven.sieb...@t-3-solutions.com> wrote: > > Hi Edward, > > I realize the typical use case for mbtiles, but my scenario is a little > different than most. What I am seeking is the most compact (disc size) > raster source possible, and based on the research of my colleague, mbtiles > what the industry uses to cache tile data on smart phones etc, so he > theorizes this is the most compact. I have him running tests to prove this > claim at the moment, which seems interesting to me as compressing image > binaries (aside from deduplication) isn't usually that significant. In the > mean time, I wanted to test the waters for community interest in this - your > response was very helpful in this regard. > > My use case is that I would like make a version of my web application > (currently bundled as an EAR, dependent on GIS services) easily deployable to > nodes that are often offline or with very poor communications. These nodes > will have no IT support, so they really need a double-click/service run sort > of operation. Rather than write a thick client application, which I will > have to maintain with an already understaffed/small team, I am looking to > leverage an embedded application server (glassfish) to serve as a container > for my apps and geoserver (war) both backed by an H2 database (for relational > an vector/metadata). Geoserver would serve as an offline/local GIS solution > for each node, which I would initially seed with some raster data but would > receive updates through a remote management service. What I am looking > toward mbtiles for is a compact raster source. A second (smaller) advantage > is it's small disc footprint in terms of number of (small/very small) files. > Since many of these deployments will be on file systems that need to be > regularly defragmented, I don't want to cause users to have to do this type > of "administrative" work (especially since they might not by delegated the > permission to do so). > > I did initially see that GeoWebCache supported this and provides WMTS (which > is great). I initially suggested we use GeoWebCaches ability to register > tiles programmatically via it's REST API to seed the cache and use this > service, but the team made a good point in that that wouldn't give WMS > services, which is important for many other clients (if we're giving them an > offline GIS server, they might as well be able to use it for all their tools > that support OGC services). Depending on the most of disc space allocated to > us, we may or may not have GeoWebCache running on the deployed system - of > course, if geoserver directly supported mbtiles, perhaps it could be done in > such a way that both system could use the same source (read only, of course) > - geoserver for WMS+ and geowebcache for WMS-C, WMTS, TMS, etc. > > I appreciate your time, and any feedback would you and the community would be > greatly appreciated. > > S > > On Tue, Jan 31, 2012 at 4:41 AM, Edward Mac Gillavry > <emacgilla...@hotmail.com> wrote: >> >> Steven, >> >> MBTiles is a storage format for tile caches. In what sense would you like to >> see GeoServer supporting MBTiles? Tile caches are typically generated with >> GeoWebCache in the context of GeoServer. Here, the MBUtil >> (https://github.com/mapbox/mbutil) could be of use to convert your directory >> based tile cache created by GWC into MBTiles and then serve it in TileMill? >> Also, MBUtil and a few other scripts (e.g. https://gist.github.com/837851 >> and https://github.com/pbarry/MBTiles-extractor) take the tiles from the >> MBTiles database and put them into a directory structure. >> >> Or would you like to see GeoServer treating an MBTiles database as it would >> cascade a WMS, i.e. yet another data store? >> >> Kind regards, >> >> Edward >> >> From: steven.sieb...@t-3-solutions.com >> Date: Mon, 30 Jan 2012 14:43:58 -0500 >> To: geoserver-users@lists.sourceforge.net >> Subject: [Geoserver-users] mbtiles support >> >> >> Hello, >> >> I've checked the email archives, JIRA, and the project Roadmap and see no >> mention of supporting MBTiles in GeoServer. I did, however, see a few >> external blogs mentioning that it was on a "long list" of items to support. >> >> I did briefly go through the trunk branch and the branches branch on the SVN >> and didn't see any existing project for this. >> >> Is there any community effort on this particular issue at the moment that >> I'm not seeing? Is there interest by the community for something like this >> in GeoServer? >> >> If creating an extension for GeoServer is the route I go...I see that GDAL >> has support for mbtiles. Can anybody give advice on this would be the right >> approach for the GeoServer architecture, our supporting the mbtiles >> specification directly would be more preferable. Any other info/interest in >> this would be good to know, which would influence myself/my company in >> investing in this effort. >> >> Regards, >> >> Steve >> >> ------------------------------------------------------------------------------ >> Keep Your Developer Skills Current with LearnDevNow! The most comprehensive >> online learning library for Microsoft developers is just $99.99! Visual >> Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. >> Free future releases when you subscribe now! >> http://p.sf.net/sfu/learndevnow-d2d >> _______________________________________________ Geoserver-users mailing list >> Geoserver-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/geoserver-users > > > > > -- > > Steven Siebert > Director Innovation and Research > T3 Solutions > (706) 791-9083 > http://www.t-3-solutions.com > > > ------------------------------------------------------------------------------ > Keep Your Developer Skills Current with LearnDevNow! > The most comprehensive online learning library for Microsoft developers > is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, > Metro Style Apps, more. Free future releases when you subscribe now! > http://p.sf.net/sfu/learndevnow-d2d > _______________________________________________ > Geoserver-users mailing list > Geoserver-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/geoserver-users > ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d _______________________________________________ Geoserver-users mailing list Geoserver-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/geoserver-users
