Old Maps Online And Georeferencer
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License | CC Attribution - NonCommercial - ShareAlike 3.0 Unported: You are free to use, adapt and copy, distribute and transmit the work or content in adapted or unchanged form for any legal and non-commercial purpose as long as the work is attributed to the author in the manner specified by the author or licensor and the work or content is shared also in adapted form only under the conditions of this | |
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00:00
Coma BerenicesProjective planeTexture mappingMappingInterface (computing)VideoconferencingPower (physics)State of matterComputer animation
00:42
CuboidRoute of administrationGamma functionUniform resource nameEmulationType theoryElectronic mailing listQuery languageResultantAreaRectangleMappingContext awarenessInterface (computing)Web pageSimilarity (geometry)Presentation of a groupCuboidInformationCovering spaceTexture mappingMusical ensembleMetropolitan area networkTime zone
02:07
Menu (computing)NumberValue-added networkSession Initiation ProtocolPhysical lawZoom lensImage resolutionSource codeXMLEngineering drawing
02:24
Digital filterScale (map)Bound stateQuery languageSimilarity (geometry)FeedbackApproximationLink (knot theory)Coma BerenicesAttribute grammarCuboidMetadataDublin CorePrice indexVirtual machineFile formatDependent and independent variablesIndependence (probability theory)Open setGoogolAlgebraic closureGoogle MapsGeometryForceInfinite conjugacy class propertyArtificial neural networkRevision controlContext awarenessPresentation of a groupMedical imagingGroup actionDatabaseMetropolitan area networkService (economics)Response time (technology)Search engine (computing)Computer fileMultiplication signScaling (geometry)Game theoryMatching (graph theory)PlanningAreaWordAlgebraic closureProjective planeIndependence (probability theory)WebsiteRevision controlPrice indexSubject indexingOrder (biology)MathematicsRow (database)Series (mathematics)Game controllerPhysical systemCoefficient of determinationResultantGreatest elementElectronic mailing listCartesian coordinate systemRight angleLatent heatFrequencyProcess (computing)Web pageWeightAttribute grammarSheaf (mathematics)GeometryKey (cryptography)Semiconductor memoryMappingDialectLine (geometry)BitBit rateFile archiverDigital photographyInterface (computing)Film editingInteractive televisionRegular graphInternetworkingEndliche ModelltheorieUniform resource locatorOpen setTexture mappingCuboidMetadataClient (computing)Read-only memoryInternet service providerFeedbackRaster graphicsQuery languageDublin CoreRepresentational state transferRankingSpline (mathematics)Binary codeData warehouseSimilarity (geometry)Web portalFile formatFilter <Stochastik>Computer animation
12:23
Film editingTexture mappingBelegleserVisualization (computer graphics)Interface (computing)Game controllerSpline (mathematics)Right anglePhysical lawComputer animation
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MappingSimultaneous localization and mappingPointer (computer programming)MappingQueue (abstract data type)Electronic mailing listWeb pageArithmetic progressionProjective planeRight angleFlow separationNeuroinformatikComputer animation
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MappingMathematical analysisGoogle MapsView (database)Google EarthUser interfaceOverlay-NetzTexture mappingResultantMathematical analysisServer (computing)Game controllerComputer fileInternet service providerScripting languageElectronic mailing listIdentifiabilitySpline (mathematics)CuboidField (computer science)MetadataView (database)Right angleCoefficient of determinationKeyboard shortcutMereologyDependent and independent variablesBitMatching (graph theory)MassComputer animation
15:30
Metropolitan area networkArtificial neural networkPresentation of a groupDifferent (Kate Ryan album)VideoconferencingTransformation (genetics)HypermediaGeometryElectronic visual displayMultiplication sign
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MetadataComputer-generated imageryThumbnailServer (computing)Source codeComa BerenicesInformationVisualization (computer graphics)MereologyProjective planeMedical imagingMatching (graph theory)Computer fileElectronic visual displayThumbnailMappingMetadataServer (computing)Computer animation
Transcript: English(auto-generated)
00:00
My name is Vaclav Krusak. I work for OCLCAN Technologies. I will be presenting to you today two of our projects. One is called Old Maps Online, the other is called Georeferencer. Old Maps Online is a project that started here in the UK at the University of Portsmouth.
00:22
It's basically what the name says. It's a large collection of old maps and it's an online portal intended for general internet users. I will now show you the interface in a short video so you can see what it looks like and what it does.
00:45
Here's the website. That's pretty much it. It's dominated by the map, which serves as a search interface. You zoom and pan on the map, as you would on Google Maps or something similar.
01:04
On the right side, the interface gives you context for what you see on the map. It will give you a list of maps from the collection that cover the same area that you are looking at. You can type a place name like London here. You will get maps of London.
01:26
When you move around, the list updates. The blue rectangle that you see, that's the query bounding box that's used for the search.
01:42
You can also specify it yourself. You can browse through the list of results. You can see more information about the map. You can go through the whole list. You can also go to another page that gives the full presentation for the map.
02:07
There you can actually look at the full resolution picture, which you will see soon.
02:26
What was that? It's a search engine for maps, basically. You find the area that you're interested in.
02:42
It's not just a search engine. It's more like a browser. You can just go to the database and start looking around. What you want to see, what you're interested in. You can also give it time and scale filters if you're interested in maps from a certain area,
03:01
of a certain scale or some specific time period. You can do that. There's also a full text filter. You can look for maps of a specific publisher or some place name that you're interested in. The list of results on the right is ordered.
03:22
It's ordered by geometric similarity to the query you're giving. It will put on the top of the list those maps that match the area that you're looking at. That's pretty important because the world maps, the maps of the whole world, they cover everything.
03:45
If you just ask for an intersection, you will get a lot of nonsensical results. If I'm interested in London, I don't want to see a world map. That's really important. Another important fact is that it has immediate feedback.
04:04
It's fast. When you pan around, you immediately see results. That's what drives the user interaction. Data in this collection comes from libraries and archives from around the world. There are around 130,000 maps right now, but we are growing.
04:26
As I said, it's a search engine. We don't steal the data. We don't get it for ourselves. We just link to the original sites. We basically provide a service to those institutions.
04:43
There's a list of the institutions that are currently in the system. How is it implemented? It uses our map rank search technology that we developed and used for several other projects as well.
05:02
Basically, it's a database. It's a collection of records, maps, but it can be anything else. Those records have geometries. We import them from well-known text or well-known binary. In the old maps online and other systems, we also associate metadata with these records.
05:27
This metadata is inspired by Dublin Core standard, but we can also provide other attributes, other kinds of data for custom purposes. As I said, the query is driven by the bounding box.
05:42
When you ask the database for something, you always give the bounding box that specifies the context that you're interested in, the place on the earth that you're interested in. It's basically a presentation technology.
06:02
It's intended for web portals that are used by many people at the same time, so it has to be fast. It's optimized for searching, not for storing. It's not really a database. It's basically an index. There are some compromises that you have to make if you want such speed.
06:26
For example, it's read-only. The database file, you have to create it again every time you change data. We have a master database of records,
06:40
and we recreate this read-only database every night or whenever there's an update. It's in a machine-dependent file format. For extra speed, we just map the file to memory. The keyword for anyone interested in databases is
07:03
borderline hybrid compressed bitmap indices. Sounds crazy, but it's basically a pretty known technique for fast indexing, for fast searches, and it's used in data warehousing and stuff like that. What's really different about this, as compared to other data structures,
07:28
the response time for the query is independent on the bounding box. As I said, it doesn't matter if you ask for the whole world or London or your house.
07:41
It should always run in the same time. It will give you the relevant results and ignore the rest, because if you use quadtree or something a little bit special, it has problems with the world maps, because if you ask for some small region, it can ignore the huge maps,
08:06
and they'll model the results. That's important. At the infrastructure side, it runs as a fast CGI application on Linux.
08:21
The URL queries conform to the open search standard, and results are in JSON, so basically you can use it as a regular REST API or HTTP API. The client that you saw, the user interface, is written in JavaScript.
08:44
We use Google Closure Tools for JavaScript to compile it, and the interface map, it can be Google Maps, OpenLayers 3, or eFlat, we don't care, or it can be something else entirely.
09:01
Okay, so if you want to get your data into old maps online, and I hope at least some of you won't, as I said, you have to give geometries for each record. The data has to be georeferenced, but these are old maps.
09:24
They belong to libraries, and what they do is basically they take the paper maps and they digitize them, they photograph them, basically. So what you get is an image, and then they put the image on their website, but that's not a map, you need a georeference,
09:41
you need to know where it is, what it covers. How do you do that? We have a service for that as well, it's called Georeferencer. Right now it's really intended for libraries and archives with large collections, and it gives them a way to georeference their data by crowdsourcing,
10:05
by using general public, regular internet users that go to their website, they get interested, and they do the georeferencing. The library gets georeferenced out of it,
10:23
and the users get some friendly competition, and nice shiny things to look at, basically. This work is sponsored by Moravian Library, it's a research project in the Czech Republic. Again, these are some institutions that already did their georeferencing with us.
10:49
How does that work? Basically, users go to the institution website, they have a large page with a plea for support, and there's usually a button that says,
11:01
okay, I'm interested, give me some map to georeference. They click the link, and they get to an interface where they add ground control points and cut lines to maps. We try hard to make it as easy as possible,
11:21
so you don't have to be logged in when you're creating the georeference. We ask you to log in afterwards, but even then, you don't have to. If you don't, we just store the georeferences anonymous, and then ask someone else to look at it and save it under his name,
11:42
so you don't have to give us anything, really. We store the full history of all edits, of all versions, so there's no problem like somebody comes in and destroys the work that someone else did. We always store only the changes, so we know exactly what happened when.
12:04
And there's a quality control. We can designate some users, usually employees of the institution, and they can go through the georeferences, verify them, and then those verified versions will go to export.
12:24
This is what it looks like. This is the georeferencing interface. There's a base map on the right, and a scanned image on the left. The user creates cut line, ground control points,
12:41
and then they save the work. If they come here from the institution website, they will go immediately from this to a 3D visualization to give them some reward. They did some work and they want to look at it, so that's what we do next.
13:05
Usually, the library will create a project page for this. There's a progress bar that says how many maps are already georeferenced, how many are still in the queue. There's a list of top contributors where people can look at it
13:26
and hope they will get there or compete with each other. We've seen some insane competitions already. What's the output? Users add ground control points, but what happens next?
13:42
Basically, anything you want to. We provide overlays over Google Maps, WMS, WMTS. As I said, you can view the result in Google Earth or download the KML,
14:00
which is usually what's really attractive to users. The reviewers can use Map Analyst for accuracy analysis. When they're verifying the work, we have a web interface to Map Analyst that runs on our server and it responds over HTTP, so we can show you distortion grids, stuff like that.
14:27
Libraries, usually they're interested in Mark 034. Mark is a standard for metadata for libraries. This field gives the bounding box of the map.
14:41
We also have a tool called GDAL Georeferencer. It's a script in Python. If you have a map in Georeferencer and it's already georeferenced, you can call this script on your master TIFF or ECW-FAR or something. You give the identifier of the map in Georeferencer
15:02
and this script will download the list of control points and create a VRT file that adds these control points to your master file. So at the end, you can warp it or do something else with it. And we also are right now adding support for annotations for linked data.
15:27
Here is the 3D view in embedded Google Earth. It's what the user sees. Here's a video of a WebGL-based presentation we're working on right now.
15:48
It's already deployed, but it looks a little bit different. We calculate the transformations on the fly in JavaScript and display it with WebGL.
16:03
So that's pretty cool. And again, we don't steal data.
16:21
You don't have to upload your TIFF files or anything. We use public image servers that are already exposed by the libraries running on their servers. We support a whole lot of image server formats. There's three of them here, but we have more.
16:42
The only image data that we store are small thumbnails that we display everywhere. Metadata that's associated with these maps is basically the same as in MapRank. So if you have a successful georeferencing project in Georeferencer,
17:01
we can just export the data and create a MapRank visualization for you. All right, that's it. Okay, I will now take questions.
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