Bingimageanalyzer is a project mainly written in PHP, it's free.
Bing Aerial Image Analyzer for OpenStreetMap
This web page shows the default bing satellite and aerial photos overlaid with their capture date as set in the HTTP headers for each tile. It uses a PHP proxy script located here[1] to create the transparent date overlay tiles. If zoomed in past zoom level 11, the page shows an approximation of the remaining zoom depth for each quarter tile. This is visualized using a semi-transparent color (greener is more remaining zoom depth) and a number.
If you want old-style overlay tiles, not showing remaining zoom depth beyond zoomlevel 11, use 'nodepth=1' in the query string.
There is probably some violation of the Bing terms of use, as I call the http headers for the tiles directly, bypassing the Bing API. I see no real way around this, but if this site stops working all of a sudden, you know why. As of version 0.8, the load on the server is reduced somewhat by disk-caching the overlay tiles when they are generated.
Copyright (c) 2010 Very Furry / Martijn van Exel
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