.. _`gdal.gdal.formats.mbtiles`:
=========
MBTiles
=========
.. versionadded:: 1.10 le pilote MBTiles permet de lire les rasters au format MBTiles, qui est
une spécification pour stocker des données cartographique tuilées dans des bases de données
SQLites.
GDAL/OGR doit être compilé avec la gestion du pilote SQLite, et des pilotes JPEG et PNG.
Le SRS esttoujours la projection Pseudo-Mercator (ie Google Mercator).
Le pilote peut récupéré les attributs des pixels encodés selon la spécification UTFGrid
disponible dans certains fichiers MBTiles. Ils peuvent être obtenu avec la commande
``gdallocationinfo`` ou avec l'appel *GetMetadataItem("Pixel_iCol_iLine", "LocationInfo")*
sur un objet bande.
Exemples
=========
* Accéder à un raster MBTiles distant :
::
$ gdalinfo /vsicurl/http://a.tiles.mapbox.com/v3/kkaefer.iceland.mbtiles
Renvoie :
::
Driver: MBTiles/MBTiles
Files: /vsicurl/http://a.tiles.mapbox.com/v3/kkaefer.iceland.mbtiles
Size is 16384, 16384
Coordinate System is:
PROJCS["WGS 84 / Pseudo-Mercator",
GEOGCS["WGS 84",
DATUM["WGS_1984",
SPHEROID["WGS 84",6378137,298.257223563,
AUTHORITY["EPSG","7030"]],
AUTHORITY["EPSG","6326"]],
PRIMEM["Greenwich",0,
AUTHORITY["EPSG","8901"]],
UNIT["degree",0.0174532925199433,
AUTHORITY["EPSG","9122"]],
AUTHORITY["EPSG","4326"]],
PROJECTION["Mercator_1SP"],
PARAMETER["central_meridian",0],
PARAMETER["scale_factor",1],
PARAMETER["false_easting",0],
PARAMETER["false_northing",0],
UNIT["metre",1,
AUTHORITY["EPSG","9001"]],
AXIS["X",EAST],
AXIS["Y",NORTH],
EXTENSION["PROJ4","+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m +nadgrids=@null +wktext +no_defs"],
AUTHORITY["EPSG","3857"]]
Origin = (-3757031.250000000000000,11271093.750000000000000)
Pixel Size = (152.873992919921875,-152.873992919921875)
Image Structure Metadata:
INTERLEAVE=PIXEL
Corner Coordinates:
Upper Left (-3757031.250,11271093.750) ( 33d44'59.95"W, 70d36'45.36"N)
Lower Left (-3757031.250, 8766406.250) ( 33d44'59.95"W, 61d36'22.97"N)
Upper Right (-1252343.750,11271093.750) ( 11d14'59.98"W, 70d36'45.36"N)
Lower Right (-1252343.750, 8766406.250) ( 11d14'59.98"W, 61d36'22.97"N)
Center (-2504687.500,10018750.000) ( 22d29'59.97"W, 66d30'47.68"N)
Band 1 Block=256x256 Type=Byte, ColorInterp=Red
Overviews: 8192x8192, 4096x4096, 2048x2048, 1024x1024, 512x512
Mask Flags: PER_DATASET ALPHA
Overviews of mask band: 8192x8192, 4096x4096, 2048x2048, 1024x1024, 512x512
Band 2 Block=256x256 Type=Byte, ColorInterp=Green
Overviews: 8192x8192, 4096x4096, 2048x2048, 1024x1024, 512x512
Mask Flags: PER_DATASET ALPHA
Overviews of mask band: 8192x8192, 4096x4096, 2048x2048, 1024x1024, 512x512
Band 3 Block=256x256 Type=Byte, ColorInterp=Blue
Overviews: 8192x8192, 4096x4096, 2048x2048, 1024x1024, 512x512
Mask Flags: PER_DATASET ALPHA
Overviews of mask band: 8192x8192, 4096x4096, 2048x2048, 1024x1024, 512x512
Band 4 Block=256x256 Type=Byte, ColorInterp=Alpha
Overviews: 8192x8192, 4096x4096, 2048x2048, 1024x1024, 512x512
* Lire des attributs de pixel encodés selon la spécification UTFGrid :
::
$ gdallocationinfo /vsicurl/http://a.tiles.mapbox.com/v3/mapbox.geography-class.mbtiles -wgs84 2 49 -b 1 -xml
Renvoie :
::
74
{"admin":"France","flag_png":"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"}
238
.. seealso::
* `Spécification MBTiles `_
* `Spécification UTFGrid `_
.. yjacolin at free.fr, Yves Jacolin - 2013/01/01 (Trunk r25229)