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This guide explains how to export (save) Nearmap imagery as a jpeg file or a georeferenced jpeg file from MapBrowser Classic. 

The export tool in the US version of MapBrowser Classic is called Export Imagery, and you can access it by selecting the Export tab from the toolbar, and then Export Imagery.

The export tool in the AU version of MapBrowser Classic is called Save Photomaps, and you can access it by selecting the camera icon from the toolbar.


You can export a defined area of Nearmap imagery as a jpeg. Optionally, you can include a georeferencing file in your export that will let you use the jpeg with GIS-enabled software.

This guide covers the following topics:

Save the Whole Map Screen

The simplest way to save a jpeg from the MapBrowser, is to select Current screen from the export tool.

Simply open the export tool as described above, and click Save. The Current Screen setting will download the whole window at exactly the resolution you see  as a .jpeg file.

You cannot choose the projection with this setting; the imagery downloads will be in EPSG:3857, Spherical Mercator projection (see Projection below). 

Please note that this process creates low resolution jpeg. To create a high resolution jpeg, see Save Part of the Displayed Map Area as a jpeg.

Save Part of the Displayed Map Area as a jpeg

To save part of the displayed map area as a jpeg:

  1. Open the export tool.
  2. Click Define Area. A suite of options will appear and a bounding box will show on the map.
  3. Resize the bounding box to define the area you want to export.
  4. From the Projection dropdown, select the projection to use. Read about the Projection setting below.
  5. From the Resolution dropdown, select your desired resolution. Read about the Export from MapBrowser Classic#Resolution setting below.
  6. Click Save.

The map area within the blue box will download as a .jpeg file at the resolution you selected, in the projection you selected.

Save Part of the Displayed Map Area as a jpeg with a Georeferencing File (.jgw)

If you want to import a Nearmap jpeg into a GIS-enabled software package, you wil need to create a georeferencing file (in .jgw format) to go with it.

To save part of the displayed map area as a jpeg with an accompanying georeferencing file:

  1. Open the export tool.
  2. Click Define Area. A suite of options will appear and a bounding box will show on the map.
  3. Resize the bounding box to define the area you want to export.
  4. From the Projection dropdown, select the projection to use. Read about the Projection setting below.
  5. From the Resolution dropdown, select your desired resolution. Read about the Export from MapBrowser Classic#Resolution setting below.
  6. Check the "Include georeference file" checkbox.
  7. Click Save.

A zip file will download with two files in it:

  • A .jpg file containing area you defined at the resolution and projection you selected 
  • A .jgw file containing georeferencing information

These files have the same name except for their extension. This means that most GIS-enabled software packages will be able to automatically find the georeference file when you import the jpeg.

About the Parameters in the Export Imagery tool

Projection

Projection is an important setting. When the spherical Earth is "projected" onto a flat map surface, distortions occur. Like Google, Bing, and MapQuest maps, we use Spherical Mercator (EPSG:3857, also known as EPSG:3785 and EPSG:900913) in our online MapBrowser. This maps the sphere to a convenient rectangle, but has large distortions away from the Equator.

When saving images, we recommend using an available local map projection so that scale and measurements are accurate.

Resolution

Resolution allows you to specify a resolution in meters per pixel. The available options are determined by the size of the blue box you define. Please note that if you save in the Spherical Mercator projection, meters/pixel is only a rough estimate due to that projection's inherent distortions.

There is a system limitation to maximum image size, which varies by coordinate system. For the default Web Mercator coordinate system, this limit is 50 megapixels. Due to the way local map projections are rendered, the maximum image size for locally projected imagery may be lower than 50 megapixels. If the area you define is too large for the highest resolution you will see the message "For a higher resolution please define a smaller area." This tool permits saving of images at extremely high aspect ratios, which can be very useful when saving along transportation routes.

File Size

File Size is a very rough estimate as to the maximum file size that will be downloaded. The actual size will often be much lower because it is difficult for us to estimate image compression efficiency in advance.

About the Optional Georeferencing File and File Naming Conventions

The Include georeference file checkbox determines whether or not a JGW sister file will download alongside your JPG image in a ZIP file. A JGW is a simple text file containing six numbers for locating the image in a coordinate system: 

  • Pixel size in the x-direction in map units
  • Rotation about y-axis (which is zero for this system)
  • Rotation about x-axis (which is zero for this system)
  • Pixel size in the y-direction in map units (often negative)
  • X-coordinate of the center of the upper left pixel
  • Y-coordinate of the center of the upper left pixel

The JGW georeference file has the same filename as the image file, and its name must always match that of the JPG. The filenames follow this format:

<projection>_Date<YYYYMMDD>_Lat<latitude>_Lon<longitude>_Mpp<resolution>

For example, an image downloaded in the EPSG:3785 (Spherical Mercator) projection from a September 10, 2015 survey centered at (37.483834,-122.144782) with resolution of 0.597 meters per pixel would have the filename:

EPSG3785_Date20150910_Lat37.483834_Lon-122.144782_Mpp0.597.jpg

You can import the image and its JGW to any application that supports georeference files. Examples are AutoCAD Map 3D or Civil 3D, ArcGIS, ArcMap, MapInfo and QGIS. See our guides on importing georeferenced jpegs for more information.