The HRPT Reader - Sample Results

You will find HRPT images on a variety of Web sites, including that of Michael Wienzek and Maurizio Bertolino.  Here are some samples, part of a larger image, just to whet your appetite.  These images were produced with the HRPT Reader available on this page.  As an example of the sort of processing you can do, I have provided an example of vegetation extraction using a local area coverage (LAC) pass raw data from the NOAA CLASS facility formerly the Satellite Active Archive.  It shows Egypt as a false-colour thumbnail, and a close-up. 

If you want to play with some raw data yourself, follow these instructions and get some data from NOAA's CLASS facility.

The rest of this page may take a few moments to load as there are a number of large images.

An APT image ...

... and its HRPT equivalent!

Iceland

Even though the sun is very low in the sky in January, thus producing good shadow detail, the histogram equalisation capability of the HRPT Reader enables the maximum use to be made of the 10 bits of video data from the AVHRR scanner.

Pass details: NOAA-16 2002 January 27 at 1313 UTC

3D images and fly-pasts

Using my extra GroundMap program to geographically rectify the output from the HRPT reader, you can produce some stunning effects by using the 3DEM 3D Terrain Visualisation and Flyby Animation software with the image.  Here are some results of this technique.  The method was described in the RIG Journal 72 by Ed Murashie, to whom many thanks are due.  You can even make an animation showing what it would be like flying over the terrain!  There is an online tutorial available on Mike Long's Web site.

Looking towards North Italy and the Alps - NOAA-17 2003 March 23 at 0958 UTC
From: Mike Jupp

The Alps from Lyon, France at 20km - NOAA-16 2003 Mar 23 at 12:57 UTC
From: Gérard Kruger

A picture looking down the Grand Canyon - NOAA 16 on 2002 Oct 15 at 20:44 UTC
Lake Powell is at the near end and Lake Mead is at the far end of the canyon
From: Ed Murashie

UK Floods

The southern part of the UK was subject to heavy floods just at the start of 2003 which caused disruption over much of England, with the Midlands and East being particularly badly affected.  The infra-red image below shows rivers swollen to an extent that I do not recall seeing before.  The land is colder, and therefore lighter, than the water in the rivers and sea, so that the rivers show up as dark lines.  This image is from NOAA-17 at 21:07 UTC on 2003-Jan-03.

Vegetation Extraction

Here raw data for a LAC pass for NOAA-14 has been downloaded and processed both with the standard false colour algorithm (using channel 2 for brightness and 4 for colour depending on temperature) and with the NDVI (normalised differential vegetation index) using channels 1 and 2, where the higher reflectivity of chlorophyll in the near infra-red is used to make a darker image.  You can e-mail me for the 1MB full resolution copy of the overview by asking for file: 200010021338.N14-fc-corrected.jpg

Pass details: NOAA-14 2000 October 02 at 1338 UTC

A regional overview image in false colour

The dark, fertile area is clustered around the Nile - resolution about 1.1km per pixel.

Popocatepetl Eruption Image of a volcanic ash cloud from this active volcano.  See here for more information.  This image shows the gridding capability (unadjusted) within the HRPT reader, and the red gridlines are at 15 and 20 degrees North and 95 and 100 degrees West.  The image is from SAA raw data, NOAA-14, 2000 December 14 at 22:59 UTC.

 

Copyright © David Taylor, Edinburgh

Last modified: 2007 Dec 23 at 15:16