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Get the link to the TIFF

The STAC Catalog, https://linz-imagery.s3-ap-southeast-2.amazonaws.com/catalog.json, is the entry point of the LINZ imagery data. It points to the different STAC Collections representing a dataset.

Note: The files on our AWS S3 bucket linz-imagery can be accessible with a s3 path s3://linz-imagery or a https URL https://linz-imagery.s3-ap-southeast-2.amazonaws.com/.

Manually navigate through the STAC Catalog to a get a TIFF

This is an example using the "Wellington 0.075m Urban Aerial Photos (2021)" dataset.

  1. From catalog.json get the Collection link for "Wellington 0.075m Urban Aerial Photos (2021)" in the links list:
{
  "rel": "child",
  "href": "./wellington/wellington_2021_0.075m/rgb/2193/collection.json",
  "title": "Wellington 0.075m Urban Aerial Photos (2021)",
  "file:checksum": "1220ca9a50511a2cb0f03229a4cc0342b30c57790f63d72221396942a18719efcd42",
  "file:size": 172494
}
  1. The Collection can be accessible from this GitHub repository, stac/wellington/wellington_2021_0.075m/rgb/2193/collection.json or from https://linz-imagery.s3-ap-southeast-2.amazonaws.com/wellington/wellington_2021_0.075m/rgb/2193/collection.json. From the Collection get an Item link in the links list:
{ "rel": "item", "href": "./BQ31_500_040071.json", "type": "application/json" }
  1. The Item can be accessible from https://linz-imagery.s3-ap-southeast-2.amazonaws.com/wellington/wellington_2021_0.075m/rgb/2193/BQ31_500_040071.json. A list of assets can be found:
"assets": {
  "visual": {
    "href": "./BQ31_500_040071.tiff",
    "type": "image/tiff; application=geotiff; profile=cloud-optimized",
    "file:checksum": "1220648bf40bb0b7e1996ac3f4ae52858ec417fcf0179e5f13e31ae6d071431c79f9"
  }
}

In this case, the TIFF can be accessible from https://linz-imagery.s3-ap-southeast-2.amazonaws.com/wellington/wellington_2021_0.075m/rgb/2193/BQ31_500_040071.tiff

Note: Our TIFF files and STAC Item files use the same base name. Having the link to the STAC Item, you can determine the TIFF link by changing its suffix from .json to .tiff.

Using STAC Browser

This tool is described in this page.

GDAL

GDAL

Virtual file system

GDAL allows you to run command on a file that is not on your local machine using a virtual file systems path:

  • /vicurl/https://linz-imagery.s3-ap-southeast-2.amazonaws.com/[PATH]
  • /vsis3/s3://linz-imagery/[PATH]

gdalinfo

gdalinfo /vsicurl/https://linz-imagery.s3-ap-southeast-2.amazonaws.com/wellington/wellington_2021_0.075m/rgb/2193/BQ31_500_040071.tiff
Output 
Driver: GTiff/GeoTIFF
Files: BQ31_500_040071.tiff
Size is 3200, 4800
Coordinate System is:
PROJCRS["NZGD2000 / New Zealand Transverse Mercator 2000",
    BASEGEOGCRS["NZGD2000",
        DATUM["New Zealand Geodetic Datum 2000",
            ELLIPSOID["GRS 1980",6378137,298.257222101,
                LENGTHUNIT["metre",1]]],
        PRIMEM["Greenwich",0,
            ANGLEUNIT["degree",0.0174532925199433]],
        ID["EPSG",4167]],
    CONVERSION["New Zealand Transverse Mercator 2000",
        METHOD["Transverse Mercator",
            ID["EPSG",9807]],
        PARAMETER["Latitude of natural origin",0,
            ANGLEUNIT["degree",0.0174532925199433],
            ID["EPSG",8801]],
        PARAMETER["Longitude of natural origin",173,
            ANGLEUNIT["degree",0.0174532925199433],
            ID["EPSG",8802]],
        PARAMETER["Scale factor at natural origin",0.9996,
            SCALEUNIT["unity",1],
            ID["EPSG",8805]],
        PARAMETER["False easting",1600000,
            LENGTHUNIT["metre",1],
            ID["EPSG",8806]],
        PARAMETER["False northing",10000000,
            LENGTHUNIT["metre",1],
            ID["EPSG",8807]]],
    CS[Cartesian,2],
        AXIS["northing (N)",north,
            ORDER[1],
            LENGTHUNIT["metre",1]],
        AXIS["easting (E)",east,
            ORDER[2],
            LENGTHUNIT["metre",1]],
    USAGE[
        SCOPE["Engineering survey, topographic mapping."],
        AREA["New Zealand - North Island, South Island, Stewart Island - onshore."],
        BBOX[-47.33,166.37,-34.1,178.63]],
    ID["EPSG",2193]]
Data axis to CRS axis mapping: 2,1
Origin = (1748800.000000000000000,5427960.000000000000000)
Pixel Size = (0.075000000000000,-0.075000000000000)
Metadata:
  AREA_OR_POINT=Area
Image Structure Metadata:
  COMPRESSION=WEBP
  INTERLEAVE=PIXEL
  LAYOUT=COG
Corner Coordinates:
Upper Left  ( 1748800.000, 5427960.000) (174d46'37.05"E, 41d17' 9.95"S)
Lower Left  ( 1748800.000, 5427600.000) (174d46'37.37"E, 41d17'21.62"S)
Upper Right ( 1749040.000, 5427960.000) (174d46'47.36"E, 41d17' 9.79"S)
Lower Right ( 1749040.000, 5427600.000) (174d46'47.68"E, 41d17'21.46"S)
Center      ( 1748920.000, 5427780.000) (174d46'42.37"E, 41d17'15.70"S)
Band 1 Block=512x512 Type=Byte, ColorInterp=Red
  Overviews: 1600x2400, 800x1200, 400x600, 200x300
  Mask Flags: PER_DATASET ALPHA
  Overviews of mask band: 1600x2400, 800x1200, 400x600, 200x300
Band 2 Block=512x512 Type=Byte, ColorInterp=Green
  Overviews: 1600x2400, 800x1200, 400x600, 200x300
  Mask Flags: PER_DATASET ALPHA
  Overviews of mask band: 1600x2400, 800x1200, 400x600, 200x300
Band 3 Block=512x512 Type=Byte, ColorInterp=Blue
  Overviews: 1600x2400, 800x1200, 400x600, 200x300
  Mask Flags: PER_DATASET ALPHA
  Overviews of mask band: 1600x2400, 800x1200, 400x600, 200x300
Band 4 Block=512x512 Type=Byte, ColorInterp=Alpha
  Overviews: 1600x2400, 800x1200, 400x600, 200x300

QGIS

Loading the TIFF

  1. In QGIS, open the "Data Source Manager" (press ctrl+L)
  2. Select "Protocol: HTTP(S)" as the "Source Type"
  3. Select "HTTP/HTTPS/FTP" as the "Protocol Type"
  4. Paste the HTTPS URL to the TIFF, for example https://linz-imagery.s3-ap-southeast-2.amazonaws.com/wellington/wellington_2021_0.075m/rgb/2193/BQ31_500_040071.tiff
  5. Click on the "Add" button and wait for the file to load.

Data Source Manager QGIS View TIFF