MediaTrackSupportedConstraints.channelCount

The MediaTrackSupportedConstraints dictionary's channelCount property is a read-only Boolean value which is present (and set to true) in the object returned by MediaDevices.getSupportedConstraints() if and only if the user agent supports the channelCount constraint. If the constraint isn't supported, it's not included in the list, so this value will never be false.

You can access the supported constraints dictionary by calling navigator.mediaDevices.getSupportedConstraints().

Syntax

channelCountConstraintSupported = supportedConstraintsDictionary.channelCount;

Value

This property is present in the dictionary (and its value is always true) if the user agent supports the channelCount constraint. If the property isn't present, this property is missing from the supported constraints dictionary, and you'll get undefined if you try to look at its value.

Example

let result = document.getElementById("result");

if (navigator.mediaDevices.getSupportedConstraints().channelCount) {
  result.innerHTML = "Supported!";
} else {
  result.innerHTML = "Not supported!";
}

Result

Specifications

Specification Status Comment
Media Capture and Streams
The definition of 'channelCount' in that specification.
Candidate Recommendation Initial specification.

Browser compatibility

DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
channelCountChrome Full support 52Edge Full support ≤79Firefox Full support 56IE ? Opera Full support YesSafari ? WebView Android Full support 52Chrome Android Full support 52Firefox Android Full support 56Opera Android Full support YesSafari iOS ? Samsung Internet Android Full support 6.0

Legend

Full support
Full support
Compatibility unknown
Compatibility unknown

See also