jeffreyveon’s answer will help reduce the chance that your user will choose deny, since she will only have to choose once.
In case she does click deny, you can provide a message that explains why you need the permission and how to update her choice. For example:
navigator.getUserMedia (
// constraints
{
video: true,
audio: true
},
// successCallback
function(localMediaStream) {
var video = document.querySelector('video');
video.src = window.URL.createObjectURL(localMediaStream);
video.onloadedmetadata = function(e) {
// Do something with the video here.
};
},
// errorCallback
function(err) {
if(err === PERMISSION_DENIED) {
// Explain why you need permission and how to update the permission setting
}
}
);