NZ Imagery Surveys dataset now available

We’re excited to release NZ Imagery Surveys — a new dataset that provides a central source to find out about the aerial imagery that we publish on the LINZ Data Service. This will make it easier to discover the aerial imagery that is most relevant to you.

Since 2012, we’ve worked with councils and other government departments to better coordinate the acquisition and dissemination of aerial imagery. This has improved ease of access and use, achieved better value for public sector investments and driven economic growth.

The NZ Imagery Surveys dataset brings together useful information about those aerial imagery surveys — information that was previously only available by examining each individual Aerial Photo Tile Index dataset and the layer metadata.

The boundary between Porirua Urban and Wellington Rural aerial imagery, with the attributes of the Porirua Urban imagery survey as shown in QGIS.

This dataset will help you determine what aerial imagery layers are available for a specific location, when they were flown, and the ground sample distance and accuracy of those layers. We’ve also included the supplier and licensor.

For example, using the flown_from and flown_to dates stored in this new composite dataset, we can display the boundaries of these imagery surveys as they’ve accumulated from 1999 to present.

NZ Imagery Surveys accumulating over time.

If we display the imagery flown during each flying season, you can also see how procurements have ramped up since 2010.

Aerial Photos datasets flown per flying season.

The flown date range for the imagery survey is important, as it sets the context for what the aerial imagery shows.

The key attributes included for each aerial imagery survey are:

Links to aerial imagery datasets

The imagery_id and index_id attributes link to the corresponding Aerial Photos and Aerial Photos Tile Index datasets on the LINZ Data Service. The identifier in these columns is part of the LINZ Data Service URL, e.g. https://data.linz.govt.nz/layer/<imagery_or_index_id>.

Set order

This is a great companion for the NZ Aerial Imagery set. The set_order attribute helps determine the imagery surveys that are included in that set and what order they are displayed in.

Ground sample distance and accuracy

An easy to consume overview of the ground sample distance and accuracy for each imagery survey is provided.

Licensor

The licensor, who should be specified when attributing aerial imagery, is also documented in this dataset. See Attributing elevation or aerial imagery data for more details.

This dataset is available for free under a Creative Commons Attribution 4.0 International license.

Download or connect to the NZ Imagery Surveys dataset here.

Check out the data dictionary here.

We used QGIS Time Manager plugin and Green Recorder to create the GIFs in this article.