MediaTrackConstraints: sampleSize property
  The MediaTrackConstraints dictionary's
  sampleSize property is a ConstrainULong
  describing the requested or mandatory constraints placed upon the value of the
  sampleSize constrainable property.
  If needed, you can determine whether or not this constraint is supported by checking
  the value of MediaTrackSupportedConstraints.sampleSize as returned by a
  call to MediaDevices.getSupportedConstraints(). However, typically this
  is unnecessary since browsers will ignore any constraints they're unfamiliar with.
Value
  If this value is a number, the user agent will attempt to obtain media whose sample
  size (in bits per linear sample) is as close as possible to this number given the
  capabilities of the hardware and the other constraints specified. Otherwise, the value
  of this ConstrainULong will guide the user agent in its efforts to provide
  an exact match to the required sample size (if exact is specified or both
  min and max are provided and have the same value) or to a
  best-possible value.
Note: Since this property can only represent linear sample sizes, this constraint can only be met by devices that can produce audio with linear samples.
Examples
See the Constraint exerciser example.
Specifications
| Specification | 
|---|
| Media Capture and Streams # dom-mediatrackconstraintset-samplesize | 
Browser compatibility
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