+
+ +
+

projinfo

+
+

New in version 6.0.0.

+
+

Geodetic object and coordinate operation queries

+
+

Synopsis

+
+
+
projinfo
+
+
[-o formats] [-k crs|operation|datum|ensemble|ellipsoid] [–summary] [-q]
+
[[–area name_or_code] | [–bbox west_long,south_lat,east_long,north_lat]]
+
[–spatial-test contains|intersects]
+
[–crs-extent-use none|both|intersection|smallest]
+
[–grid-check none|discard_missing|sort|known_available]
+
[–pivot-crs always|if_no_direct_transformation|never|{auth:code[,auth:code]*}]
+
[–show-superseded] [–hide-ballpark] [–accuracy {accuracy}]
+
[–allow-ellipsoidal-height-as-vertical-crs]
+
[–boundcrs-to-wgs84]
+
[–authority name]
+
[–main-db-path path] [–aux-db-path path]*
+
[–dump-db-structure]
+
[–identify] [–3d]
+
[–output-id AUTH:CODE]
+
[–c-ify] [–single-line]
+
–searchpaths | –remote-data |
+
–list-crs [list-crs-filter] |
+
–dump-db-structure [{object_definition} | {object_reference}] |
+
{object_definition} | {object_reference} | (-s {srs_def} -t {srs_def})
+

+
+
+

where {object_definition} or {srs_def} is one of the possibilities accepted +by proj_create()

+ +

{object_reference} is a filename preceded by the ‘@’ character. The +file referenced by the {object_reference} must contain a valid +{object_definition}.

+
+
+
+

Description

+

projinfo is a program that can query information on a geodetic object, +coordinate reference system (CRS) or coordinate operation, when the -s and -t +options are specified, and display it under different formats (PROJ string, WKT string +or PROJJSON string).

+

It can also be used to query coordinate operations available between two CRS.

+

The program is named with some reference to the GDAL gdalsrsinfo that offers +partly similar services.

+

The following control parameters can appear in any order:

+
+
+-o formats
+

formats is a comma separated combination of: +all, default, PROJ, WKT_ALL, WKT2:2015, WKT2:2019, WKT1:GDAL, WKT1:ESRI, PROJJSON, SQL.

+

Except all and default, other formats can be preceded by - to disable them.

+
+

Note

+

WKT2_2019 was previously called WKT2_2018.

+
+
+

Note

+

Before PROJ 6.3.0, WKT1:GDAL was implicitly calling –boundcrs-to-wgs84. +This is no longer the case.

+
+
+

Note

+

When SQL is specified, --output-id must be specified.

+
+
+ +
+
+-k crs|operation|datum|ensemble|ellipsoid
+

When used to query a single object with a AUTHORITY:CODE, determines the (k)ind of the object +in case there are CRS, coordinate operations or ellipsoids with the same CODE. +The default is crs.

+
+ +
+
+--summary
+

When listing coordinate operations available between 2 CRS, return the +result in a summary format, mentioning only the name of the coordinate +operation, its accuracy and its area of use.

+
+

Note

+

only used for coordinate operation computation

+
+
+ +
+
+-q
+

Turn on quiet mode. Quiet mode is only available for queries on single objects, +and only one output format is selected. In that mode, only the PROJ, WKT or PROJJSON +string is displayed, without other introduction output. The output is then +potentially compatible of being piped in other utilities.

+
+ +
+
+--area name_or_code
+

Specify an area of interest to restrict the results when researching +coordinate operations between 2 CRS. The area of interest can be specified either +as a name (e.g “Denmark - onshore”) or a AUTHORITY:CODE (EPSG:3237) +This option is exclusive of --bbox.

+
+

Note

+

only used for coordinate operation computation

+
+
+ +
+
+--bbox west_long,south_lat,east_long,north_lat
+

Specify an area of interest to restrict the results when researching +coordinate operations between 2 CRS. The area of interest is specified as a +bounding box with geographic coordinates, expressed in degrees in a +unspecified geographic CRS. +west_long and east_long should be in the [-180,180] range, and +south_lat and north_lat in the [-90,90]. west_long is generally lower than +east_long, except in the case where the area of interest crosses the antimeridian.

+
+

Note

+

only used for coordinate operation computation

+
+
+ +
+
+--spatial-test contains|intersects
+

Specify how the area of use of coordinate operations found in the database +are compared to the area of use specified explicitly with --area or --bbox, +or derived implicitly from the area of use of the source and target CRS. +By default, projinfo will only keep coordinate operations whose are of use +is strictly within the area of interest (contains strategy). +If using the intersects strategy, the spatial test is relaxed, and any +coordinate operation whose area of use at least partly intersects the +area of interest is listed.

+
+

Note

+

only used for coordinate operation computation

+
+
+ +
+
+--crs-extent-use none|both|intersection|smallest
+

Specify which area of interest to consider when no explicit one is specified +with --area or --bbox options. +By default (smallest strategy), the area of +use of the source or target CRS will be looked, and the one that is the +smallest one in terms of area will be used as the area of interest. +If using none, no area of interest is used. +If using both, only coordinate operations that relate (contain or intersect +depending of the --spatial-test strategy) to the area of use of both CRS +are selected. +If using intersection, the area of interest is the intersection of the +bounding box of the area of use of the source and target CRS

+
+

Note

+

only used for coordinate operation computation

+
+
+ +
+
+--grid-check none|discard_missing|sort|known_available
+

Specify how the presence or absence of a horizontal or vertical shift grid +required for a coordinate operation affects the results returned when +researching coordinate operations between 2 CRS. +The default strategy is sort (if PROJ_NETWORK is not defined). +In that case, all candidate +operations are returned, but the actual availability of the grids is used +to determine the sorting order. That is, if a coordinate operation involves +using a grid that is not available in the PROJ resource directories +(determined by the PROJ_LIB environment variable, it will be listed in +the bottom of the results. +The none strategy completely disables the checks of presence of grids and +this returns the results as if all the grids where available. +The discard_missing strategy discards results that involve grids not +present in the PROJ resource directories. +The known_available strategy discards results that involve grids not +present in the PROJ resource directories and that are not known of the CDN. +This is the default strategy is PROJ_NETWORK is set to ON.

+
+

Note

+

only used for coordinate operation computation

+
+
+ +
+
+--pivot-crs always|if_no_direct_transformation|never|{auth:code[,auth:code]*}
+

Determine if intermediate (pivot) CRS can be used when researching coordinate +operation between 2 CRS. A typical example is the WGS84 pivot. By default, +projinfo will consider any potential pivot if there is no direct transformation +( if_no_direct_transformation). If using the never strategy, +only direct transformations between the source and target CRS will be +used. If using the always strategy, intermediate CRS will be considered +even if there are direct transformations. +It is also possible to restrict the pivot CRS to consider by specifying +one or several CRS by their AUTHORITY:CODE.

+
+

Note

+

only used for coordinate operation computation

+
+
+ +
+
+--show-superseded
+

When enabled, coordinate operations that are superseded by others will be +listed. Note that supersession is not equivalent to deprecation: superseded +operations are still considered valid although they have a better equivalent, +whereas deprecated operations have been determined to be erroneous and are +not considered at all.

+
+

Note

+

only used for coordinate operation computation

+
+
+ +
+
+--hide-ballpark
+
+

New in version 7.1.

+
+

Hides any coordinate operation that is, or contains, a +Ballpark transformation

+
+

Note

+

only used for coordinate operation computation

+
+
+ +
+
+--accuracy {accuracy}
+
+

New in version 8.0.

+
+

Sets the minimum desired accuracy for returned coordinate operations.

+
+

Note

+

only used for coordinate operation computation

+
+
+ +
+
+--allow-ellipsoidal-height-as-vertical-crs
+
+

New in version 8.0.

+
+

Allows exporting a geographic or projected 3D CRS as a compound CRS whose +vertical CRS represents the ellipsoidal height.

+
+

Note

+

only used for CRS, and with WKT1:GDAL output format

+
+
+ +
+
+--boundcrs-to-wgs84
+

When specified, this option researches a coordinate operation from the +base geographic CRS of the single CRS, source or target CRS to the WGS84 +geographic CRS, and if found, wraps those CRS into a BoundCRS object. +This is mostly to be used for early-binding approaches.

+
+ +
+
+--authority name
+

Specify the name of the authority into which to restrict looks up for +objects, when specifying an object by name or when coordinate operations are +computed. The default is to allow all authorities.

+

When used with SQL output, this restricts the authorities to which intermediate +objects can belong to (the default is EPSG and PROJ). Note that the authority +of the --output-id option will also be implicitly added.

+
+ +
+
+--main-db-path path
+

Specify the name and path of the database to be used by projinfo. +The default is proj.db in the PROJ resource directories.

+
+ +
+
+--aux-db-path path
+

Specify the name and path of auxiliary databases, that are to be combined +with the main database. Those auxiliary databases must have a table +structure that is identical to the main database, but can be partly filled +and their entries can refer to entries of the main database. +The option may be repeated to specify several auxiliary databases.

+
+ +
+
+--identify
+

When used with an object definition, this queries the PROJ database to find +known objects, typically CRS, that are close or identical to the object. +Each candidate object is associated with an approximate likelihood percentage. +This is useful when used with a WKT string that lacks a EPSG identifier, +such as ESRI WKT1. This might also be used with PROJ strings. +For example, +proj=utm +zone=31 +datum=WGS84 +type=crs will be identified +with a likelihood of 70% to EPSG:32631

+
+ +
+
+--dump-db-structure
+
+

New in version 8.1.

+
+

Outputs the sequence of SQL statements to create a new empty valid auxiliary +database. This option can be specified as the only switch of the utility. +If also specifying a CRS object and the --output-id option, the +definition of the object as SQL statements will be appended.

+
+ +
+
+--list-crs [list-crs-filter]
+
+

New in version 8.1.

+
+

Outputs a list (authority name:code and CRS name) of the filtered CRSs from the database. +If no filter is provided all authority names and types of non deprecated CRSs are dumped. +list-crs-filter is a comma separated combination of: allow_deprecated,geodetic,geocentric, +geographic,geographic_2d,geographic_3d,vertical,projected,compound. +Affected by options --authority, --area, --bbox and --spatial-test

+
+ +
+
+--3d
+
+

New in version 6.3.

+
+

“Promote” the CRS(s) to their 3D version. In the context of researching +available coordinate transformations, explicitly specifying this option is +not necessary, because when one of the source or target CRS has a vertical +component but not the other one, the one that has no vertical component is +automatically promoted to a 3D version, where its vertical axis is the +ellipsoidal height in metres, using the ellipsoid of the base geodetic CRS.

+
+ +
+
+--output-id=AUTH:NAME
+
+

New in version 8.1.

+
+

Identifier to assign to the object (for SQL output).

+

It is strongly recommended that new objects should not be added in common +registries, such as EPSG, ESRI, IAU, etc. +Users should use a custom authority name instead. If a new object should be +added to the official EPSG registry, users are invited to follow the +procedure explained at https://epsg.org/dataset-change-requests.html.

+

Combined with --dump-db-structure, users can create +auxiliary databases, instead of directly modifying the main proj.db database. +See the example how to export to an auxiliary database.

+

Those auxiliary databases can be specified through +proj_context_set_database_path() or the PROJ_AUX_DB +environment variable.

+
+ +
+
+--c-ify
+

For developers only. Modify the string output of the utility so that it +is easy to put those strings in C/C++ code

+
+ +
+
+--single-line
+

Output PROJ, WKT or PROJJSON strings on a single line, instead of multiple +indented lines by default.

+
+ +
+
+--searchpaths
+
+

New in version 7.0.

+
+

Output the directories into which PROJ resources will be looked for +(if not using C API such as proj_context_set_search_paths() +that will override them.

+
+ +
+
+--remote-data
+
+

New in version 7.0.

+
+

Display information regarding if Network capabilities is enabled, and the +related URL.

+
+ +
+
+

Examples

+
    +

  1. Query the CRS object corresponding to EPSG:4326

    2. +
+
projinfo EPSG:4326
+
+
+

Output:

+
PROJ.4 string:
++proj=longlat +datum=WGS84 +no_defs +type=crs
+
+WKT2:2019 string:
+GEOGCRS["WGS 84",
+    DATUM["World Geodetic System 1984",
+        ELLIPSOID["WGS 84",6378137,298.257223563,
+            LENGTHUNIT["metre",1]]],
+    PRIMEM["Greenwich",0,
+        ANGLEUNIT["degree",0.0174532925199433]],
+    CS[ellipsoidal,2],
+        AXIS["geodetic latitude (Lat)",north,
+            ORDER[1],
+            ANGLEUNIT["degree",0.0174532925199433]],
+        AXIS["geodetic longitude (Lon)",east,
+            ORDER[2],
+            ANGLEUNIT["degree",0.0174532925199433]],
+    USAGE[
+        SCOPE["unknown"],
+        AREA["World"],
+        BBOX[-90,-180,90,180]],
+    ID["EPSG",4326]]
+
+
+
    +

  1. List the coordinate operations between NAD27 (designed with its CRS name) +and NAD83 (designed with its EPSG code 4269) within an area of interest

    2. +
+
projinfo -s NAD27 -t EPSG:4269 --area "USA - Missouri"
+
+
+

Output:

+
DERIVED_FROM(EPSG):1241, NAD27 to NAD83 (1), 0.15 m, USA - CONUS including EEZ
+
+PROJ string:
++proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert \
++xy_in=deg +xy_out=rad +step +proj=hgridshift +grids=conus \
++step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1
+
+WKT2:2019 string:
+COORDINATEOPERATION["NAD27 to NAD83 (1)",
+    SOURCECRS[
+        GEOGCRS["NAD27",
+            DATUM["North American Datum 1927",
+                ELLIPSOID["Clarke 1866",6378206.4,294.978698213898,
+                    LENGTHUNIT["metre",1]]],
+            PRIMEM["Greenwich",0,
+                ANGLEUNIT["degree",0.0174532925199433]],
+            CS[ellipsoidal,2],
+                AXIS["geodetic latitude (Lat)",north,
+                    ORDER[1],
+                    ANGLEUNIT["degree",0.0174532925199433]],
+                AXIS["geodetic longitude (Lon)",east,
+                    ORDER[2],
+                    ANGLEUNIT["degree",0.0174532925199433]]]],
+    TARGETCRS[
+        GEOGCRS["NAD83",
+            DATUM["North American Datum 1983",
+                ELLIPSOID["GRS 1980",6378137,298.257222101,
+                    LENGTHUNIT["metre",1]]],
+            PRIMEM["Greenwich",0,
+                ANGLEUNIT["degree",0.0174532925199433]],
+            CS[ellipsoidal,2],
+                AXIS["geodetic latitude (Lat)",north,
+                    ORDER[1],
+                    ANGLEUNIT["degree",0.0174532925199433]],
+                AXIS["geodetic longitude (Lon)",east,
+                    ORDER[2],
+                    ANGLEUNIT["degree",0.0174532925199433]]]],
+    METHOD["CTABLE2"],
+    PARAMETERFILE["Latitude and longitude difference file","conus"],
+    OPERATIONACCURACY[0.15],
+    USAGE[
+        SCOPE["unknown"],
+        AREA["USA - CONUS including EEZ"],
+        BBOX[23.81,-129.17,49.38,-65.69]],
+    ID["DERIVED_FROM(EPSG)",1241]]
+
+
+
    +

  1. Export an object as a PROJJSON string

    2. +
+
projinfo GDA94 -o PROJJSON -q
+
+
+

Output:

+
{
+    "type": "GeographicCRS",
+    "name": "GDA94",
+    "datum": {
+        "type": "GeodeticReferenceFrame",
+        "name": "Geocentric Datum of Australia 1994",
+        "ellipsoid": {
+            "name": "GRS 1980",
+            "semi_major_axis": 6378137,
+            "inverse_flattening": 298.257222101
+        }
+    },
+    "coordinate_system": {
+        "subtype": "ellipsoidal",
+        "axis": [
+        {
+            "name": "Geodetic latitude",
+            "abbreviation": "Lat",
+            "direction": "north",
+            "unit": "degree"
+        },
+        {
+            "name": "Geodetic longitude",
+            "abbreviation": "Lon",
+            "direction": "east",
+            "unit": "degree"
+        }
+        ]
+    },
+    "area": "Australia - GDA",
+    "bbox": {
+        "south_latitude": -60.56,
+        "west_longitude": 93.41,
+        "north_latitude": -8.47,
+        "east_longitude": 173.35
+    },
+    "id": {
+        "authority": "EPSG",
+        "code": 4283
+    }
+}
+
+
+
    +

  1. Exporting the SQL statements to insert a new CRS in an auxiliary database.

    2. +
+
# Get the SQL statements for a custom CRS
+projinfo "+proj=merc +lat_ts=5 +datum=WGS84 +type=crs +title=my_crs" --output-id HOBU:MY_CRS -o SQL -q > my_crs.sql
+cat my_crs.sql
+
+# Initialize an auxiliary database with the schema of the reference database
+echo ".schema" | sqlite3 /path/to/proj.db | sqlite3 aux.db
+
+# Append the content of the definition of HOBU:MY_CRS
+sqlite3 aux.db < my_crs.db
+
+# Check that everything works OK
+projinfo --aux-db-path aux.db HOBU:MY_CRS
+
+
+

or more simply:

+
# Create an auxiliary database with the definition of a custom CRS.
+projinfo "+proj=merc +lat_ts=5 +datum=WGS84 +type=crs +title=my_crs" --output-id HOBU:MY_CRS --dump-db-structure | sqlite3 aux.db
+
+# Check that everything works OK
+projinfo --aux-db-path aux.db HOBU:MY_CRS
+
+
+

Output:

+
INSERT INTO geodetic_crs VALUES('HOBU','GEODETIC_CRS_MY_CRS','unknown','','geographic 2D','EPSG','6424','EPSG','6326',NULL,0);
+INSERT INTO usage VALUES('HOBU','USAGE_GEODETIC_CRS_MY_CRS','geodetic_crs','HOBU','GEODETIC_CRS_MY_CRS','PROJ','EXTENT_UNKNOWN','PROJ','SCOPE_UNKNOWN');
+INSERT INTO conversion VALUES('HOBU','CONVERSION_MY_CRS','unknown','','EPSG','9805','Mercator (variant B)','EPSG','8823','Latitude of 1st standard parallel',5,'EPSG','9122','EPSG','8802','Longitude of natural origin',0,'EPSG','9122','EPSG','8806','False easting',0,'EPSG','9001','EPSG','8807','False northing',0,'EPSG','9001',NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,0);
+INSERT INTO usage VALUES('HOBU','USAGE_CONVERSION_MY_CRS','conversion','HOBU','CONVERSION_MY_CRS','PROJ','EXTENT_UNKNOWN','PROJ','SCOPE_UNKNOWN');
+INSERT INTO projected_crs VALUES('HOBU','MY_CRS','my_crs','','EPSG','4400','HOBU','GEODETIC_CRS_MY_CRS','HOBU','CONVERSION_MY_CRS',NULL,0);
+INSERT INTO usage VALUES('HOBU','USAGE_PROJECTED_CRS_MY_CRS','projected_crs','HOBU','MY_CRS','PROJ','EXTENT_UNKNOWN','PROJ','SCOPE_UNKNOWN');
+
+
+
PROJ.4 string:
++proj=merc +lat_ts=5 +lon_0=0 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs +type=crs
+
+WKT2:2019 string:
+PROJCRS["my_crs",
+    BASEGEOGCRS["unknown",
+        ENSEMBLE["World Geodetic System 1984 ensemble",
+            MEMBER["World Geodetic System 1984 (Transit)"],
+            MEMBER["World Geodetic System 1984 (G730)"],
+            MEMBER["World Geodetic System 1984 (G873)"],
+            MEMBER["World Geodetic System 1984 (G1150)"],
+            MEMBER["World Geodetic System 1984 (G1674)"],
+            MEMBER["World Geodetic System 1984 (G1762)"],
+            ELLIPSOID["WGS 84",6378137,298.257223563,
+                LENGTHUNIT["metre",1]],
+            ENSEMBLEACCURACY[2.0]],
+        PRIMEM["Greenwich",0,
+            ANGLEUNIT["degree",0.0174532925199433]],
+        ID["HOBU","GEODETIC_CRS_MY_CRS"]],
+    CONVERSION["unknown",
+        METHOD["Mercator (variant B)",
+            ID["EPSG",9805]],
+        PARAMETER["Latitude of 1st standard parallel",5,
+            ANGLEUNIT["degree",0.0174532925199433],
+            ID["EPSG",8823]],
+        PARAMETER["Longitude of natural origin",0,
+            ANGLEUNIT["degree",0.0174532925199433],
+            ID["EPSG",8802]],
+        PARAMETER["False easting",0,
+            LENGTHUNIT["metre",1],
+            ID["EPSG",8806]],
+        PARAMETER["False northing",0,
+            LENGTHUNIT["metre",1],
+            ID["EPSG",8807]]],
+    CS[Cartesian,2],
+        AXIS["(E)",east,
+            ORDER[1],
+            LENGTHUNIT["metre",1]],
+        AXIS["(N)",north,
+            ORDER[2],
+            LENGTHUNIT["metre",1]],
+    ID["HOBU","MY_CRS"]]
+
+
+
    +

  1. Get the WKT representation of EPSG:25832 in the WKT1:GDAL output format and on a single line

    2. +
+
projinfo -o WKT1:GDAL --single-line EPSG:25832
+
+
+

Output:

+
WKT1:GDAL string:
+PROJCS["ETRS89 / UTM zone 32N",GEOGCS["ETRS89",DATUM["European_Terrestrial_Reference_System_1989",SPHEROID["GRS 1980",6378137,298.257222101,AUTHORITY["EPSG","7019"]],AUTHORITY["EPSG","6258"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4258"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",0],PARAMETER["central_meridian",9],PARAMETER["scale_factor",0.9996],PARAMETER["false_easting",500000],PARAMETER["false_northing",0],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","25832"]]
+
+
+
+
+ + +
+