{"json_modified": "2016-10-07T15:41:19.455659", "uuid": "dc6c7dc1-6bda-4346-a2b8-9c9a4729b26f", "title": "MediaStreamTrack.getConstraints()", "url": "/en-US/docs/Web/API/MediaStreamTrack/getConstraints", "tags": ["API", "Media Capture and Streams", "getConstraints", "MediaStreamTrack", "Reference", "Media Streams API", "Method"], "translations": [], "modified": "2016-10-07T15:41:19", "label": "MediaStreamTrack.getConstraints()", "localization_tags": [], "locale": "en-US", "id": 192193, "last_edit": "2016-10-07T15:41:14", "summary": "The <strong><code>getConstraints()</code></strong> method of the <a href=\"/en-US/docs/Web/API/MediaStreamTrack\" title=\"The MediaStreamTrack interface represents&#xA0;a single media track within a stream; typically, these are audio or video tracks, but other track types may exist as well.\"><code>MediaStreamTrack</code></a> interface returns\u00a0a <a href=\"/en-US/docs/Web/API/MediaTrackConstraints\" title=\"The MediaTrackConstraints dictionary is used to describe a set of capabilities and the value or values each can take on. A constraints dictionary is passed into applyConstraints() to allow a script to establish a set of exact (required) values or ranges and/or preferred values or ranges of values for the track, and the most recently-requested set of custom constraints can be retrieved by calling getConstraints().\"><code>MediaTrackConstraints</code></a>\u00a0object containing the set of constraints most recently established for the track using a prior call to <a href=\"/en-US/docs/Web/API/MediaStreamTrack/applyConstraints\" title=\"The applyConstraints() method of the MediaStreamTrack interface applies a set of constraints to the track; these constraints let the Web site or app establish ideal values and acceptable ranges of values for the constrainable properties of the track, such as frame rate, dimensions, echo cancelation, and so forth.\"><code>applyConstraints()</code></a>. These constraints indicate values and ranges of values that the Web site or application has specified are required or acceptable for the included constrainable properties.", "sections": [{"id": "Quick_Links", "title": null}, {"id": "Syntax", "title": "Syntax"}, {"id": "Parameters", "title": "Parameters"}, {"id": "Return_value", "title": null}, {"id": "Example", "title": "Example"}, {"id": "Specifications", "title": "Specifications"}, {"id": "Browser_compatibility", "title": "Browser compatibility"}], "slug": "Web/API/MediaStreamTrack/getConstraints", "review_tags": []}