Section: 4.5.3 Image Movie Format

4.5.3 Image Movie Format

Image Movie Files The IDV can display a sequence of time-stamped images as an animation. This is most commonly used with the Web-Cam Display Control.

One can write their own xml file and display the images within the IDV using this xml format.

There are really two xml formats used. The first defines a set of imagesets:

<imagesets base="https://resources.unidata.ucar.edu/georesources/webcams/images" name="IDV Webcams">
    <group name="Rockies">
        <imageset name="Boulder, CO"  
                  index="boulder_co/index.xml"  
                  lat="40.0" lon="-105.27"/>
        <imageset name="Denver, CO"  
                  index="denver_co/index.xml"  
                  lat="39.75" lon="-105"/>
    </group>
    <group name="National Parks">
        <imageset name="Theodore Roosevelt National Park, ND"  
                  index="theodorerooseveltnationalpark_nd/index.xml"  
                  lat="46.94889" lon="-103.43306"/>
        <imageset name="Big Bend National Park,TX"  
                  index="bigbendnationalpark_tx/index.xml"  
                  lat="29.25" lon="-103.25"/>
        <imageset name="Olympic National Park"  
                  index="olympicnationalpark/index.xml"  
                  lat="48.26667" lon="-124.675"/>
    </group>
    ...
</imagesets>

This is a "table of contents". The base attribute, if defined, is used as a url base to prepend to the urls defined by the index attributes. This file can be imported by the Web-Cam Display Control. The lat and lon attributes are optional and are used to locate the source of the movie on a map for the user to select.

Each of the index attributes refers to an images xml file of the form:

<images base="https://resources.unidata.ucar.edu/georesources/webcams/images/boulder_co"
        name="Boulder, CO" 
        group="Rockies" 
        format="yyyyMMddHHmmz" desc="From: http://9news.com">
    <image time="200607251446GMT" file="image_200607251446GMT.jpeg"/>
    <image time="200607251430GMT" file="image_200607251430GMT.jpeg"/>
    <image time="200607251414GMT" file="image_200607251414GMT.jpeg"/>
    <image time="200607251357GMT" file="image_200607251357GMT.jpeg"/>
    <image time="200607251344GMT" file="image_200607251344GMT.jpeg"/>
    ...
</images>

The images tag defines a base attribute (optional, used to prepend to any image urls), a name, a (optional) group and a date format and a description (desc). Each image tag has a time in the format specified in the images tag and a file attribute which refers to some image. This may be an absolute or relative url or file path.

This file can also be directly imported by the Web-Cam Display Control.

Unidata IDV Workshop for version 6.2u2 > Advanced Topics > Miscellaneous Items