MICROSOFT_PRESS_EBOOK_PROGRAMMING_WINDOWS_8_APPS_WITH_HTML_CSS_AND_JAVASCRIPT_PDF

}
return degrees + "°" + minutes + "\'" + seconds + "\"" + reference;
To summarize, the sign of the value indicates direction. A positive value for latitude means North,
negative means South; for longitude, positive means East, negative means West. The whole number
portion of the value provides the degrees, and the fractional part contains the number of minutes
expressed in base 60. Multiplying this value by 60 gives the whole minutes, with the remainder then
containing the seconds. It’s odd, but that’s the kind of raw data you get from a GPS device that
geolocation APIs normally convert for you directly.
Media Properties in the Samples
A few of the samples in the Windows SDK show you how to work with some of the properties described
in the last section and how to work with those properties more generally. The Simple imaging sample, in
Scenario 1 (js/scenario1.js), provides the most complete demonstration because you can choose an
image file and it will load and display various properties, as shown in Figure 10-5 (I’ve scrolled down to
see all the properties). I can verify that the date, camera make/model, and exposure information are all
accurate.
FIGURE 10-5 Image file properties in the Simple imaging sample.
The sample’s openHandler method is what retrieves these properties from the file, specifically
showing a call to StorageFile.properties.getImagePropertiesAsync and the use of
ImageProperties.retrievePropertiesAsync for a couple of additional properties not already in
ImageProperties. Then getImagePropertiesForDisplay coalesces these into a single object used by the
sample’s UI. Some lines are omitted in the code shown here:
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