MICROSOFT_PRESS_EBOOK_PROGRAMMING_WINDOWS_8_APPS_WITH_HTML_CSS_AND_JAVASCRIPT_PDF

vid.msInsertVideoEffect("GrayscaleTransform.GrayscaleEffect", true, null);
vid.msInsertVideoEffect("InvertTransform.InvertEffect", true, null);
The second parameter to msInsertVideoEffect, by the way, indicates whether the effect is required,
so it’s typically true. The third is a parameter called config, which just contains additional information to
pass to the effect. In the case of the geometric effects in the sample, this parameter specifies the
particular variation:
var effect = new Windows.Foundation.Collections.PropertySet();
effect["effect"] = effectName;
vid.msClearEffects();
vid.msInsertVideoEffect("PolarTransform.PolarEffect", true, effect);
where effectName will be either “Fisheye”, “Pinch”, or “Warp”.
Audio effects, not shown in the sample, are applied the same way with msInsertAudioEffect (with
the same parameters). Do note that each element can have at most two effects per media stream. A
video element can have two video effects and two audio effects; an audio element can have two audio
effects. If you try to add more, the methods will throw an exception. This is why it’s a good idea to call
msClearEffects before inserting any others.
For additional discussion on effects and other media extensions, see Using media extensions.
Browsing Media Servers
Many households, including my own, have one or more media servers available on the local network
from which apps can play media. Getting to these servers is the purpose of the one other property in
Windows.Storage.KnownFolders that we haven’t mentioned yet: mediaServerDevices. As with other
known folders, this is simply a StorageFolder object through which you can then enumerate or query
additional folders and files. In this case, if you call its getFoldersAsync, you’ll receive back a list of
available servers, each of which is represented by another StorageFolder. From there you can use file
queries, as discussed in Chapter 8, “State, Settings, Libraries, and Documents,” to search for the types of
media you’re interested in or apply user-provided search criteria. An example of this can be found in the
Media Server client sample.
Audio Playback and Mixing
As with video, the audio element provides its own playback abilities, including controls, looping, and
autoplay:
Again, as described earlier, the same W3C spec applies to both video and audio elements. The same
code to play just the audio portion of a video is exactly what we use to play an audio file:
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