How to change the current time in the progress control? - video.js

Is it possible to manualy set the current time position on the timeline? I need this because I have several separated videos which represent one video and are playing in different players.
For example, the actual current time is marked as white dot, the desired current time that I want to show as red dot.
Can I do this somehow without creating completely new custom controlbar?

Middleware could be part of the solution, which allows you to intercept and modify what's sent to / received from the playback tech (video element).
var myMiddleware = function(player) {
return {
currentTime: function(ct) {
// When the video el says the currentTime is 60s, report 160s
return ct + 100;
},
setCurrentTime: function(time) {
// When the user / progress bar wants to seek to 220s, actually seek to 120s
return time - 100;
}
};
};
videojs.use('*', myMiddleware);

Related

Synchronizing TWEEN, CCapture, and THREE.js rendering code to all be on the same clock

I'm using a library called CCapture to capture equally time-spaced frames. This code seems to be able to hook the clock and control it so that is slows down my rendering loop when it is capturing. My code uses clock.getDelta() to get the time and it uses this time to calculate the positions of moving transit vehicles. When CCapture controls the rendering rate, the vehicles are correctly positioned.
I recently started using the TWEEN library in my code.
function animate() {
renderer.setAnimationLoop( renderFrame );
}
function renderFrame() {
const delta = clock.getDelta()
timeSinceStart += delta;
repositionTransitVehicles(timeSinceStart);
renderer.render(scene, camera);
if (capturer) {
capturer.capture( renderer.domElement );
}
orbitControls.enabled = false;
TWEEN.update();
orbitControls.enabled = true;
orbitControls.update();
},
With the no-arguments version of TWEEN.update(), tweening works but always proceeds at real time, which is too fast when I'm using CCapture. If I use...
TWEEN.update(timeSinceStart)
...then tweening does not work at all.
Does anyone know the secret to making TWEEN.update() operate using the same clock as the rest of the model?
The timer that TWEEN uses is a millisecond timer, an thus the units of the time that need to be passed into TWEEN.update() need to be in units of milliseconds. The units of THREE.Clock() are seconds. So use...
TWEEN.update(timeSinceStart*1000)
Wherever you use TWEEN's .start() method to initiate your tweens, you will also need to pass in the argument timeSinceStart*1000 as well.

Titanium geolocation distanceFilter property is not working as expected

Need a help here for geolocation API - even after using Titanium.Geolocation.distanceFilter = 10; 10 in meter callback function is getting triggered randomly without moving here and there. Any idea what is wrong here ?
function Geolocate() {
var self = this;
// The callback function we should call when location is finally determined
this.locationReceivedCallback = function () {};
// Check if location event is already triggered or not
this.isLocationEventRegister = false;
// The function that unregisters the location event
this.unregisterLocationEvent = function () {
this.isLocationEventRegister = false;
Ti.Geolocation.removeEventListener('location', self.locationReceivedCallback);
};
}
Geolocate.prototype.init = function () {
// Setting up some preference values
Titanium.Geolocation.distanceFilter = 10; //The minimum change of position (in meters) before a 'location' event is fired.
if (deviceDetect.isIos()) {
Titanium.Geolocation.accuracy = Titanium.Geolocation.ACCURACY_BEST; // Using this value on Android enables legacy mode operation, which is not recommended.
} else {
Titanium.Geolocation.accuracy = Titanium.Geolocation.ACCURACY_LOW; //Using this value on Android enables simple mode operation.
}
};
Geolocate.prototype.getCurrentPosition = function (callback) {
this.isLocationEventRegister = true;
this.locationReceivedCallback = callback;
Titanium.Geolocation.addEventListener("location", this.locationReceivedCallback);
};
Geolocate.prototype.locationServicesAreAvailable = function () {
if (Titanium.Geolocation.locationServicesEnabled) {
return true;
} else {
return false;
}
};
Geolocate.prototype.cancelLocationRequest = function () {
this.unregisterLocationEvent();
};
module.exports = Geolocate;
Actual scenario is whenever I clicked on get location its gives me current location. then i tried to drag it map or image view for nearest place. Suddenly my view go current location. This is happening because of call back ? How to get rid off this ?
It's not a problem to do with your code, it is simply GPS in-accuracy.
GPS accuracy is (almost) never better than 10 meters, meaning it can be 10 meters off. When it recalculates your position it can be 10 meters down the line, so even if you're perfectly still with perfect GPS accuracy, you still might have differences of about 10 meters.
That said, you probably don't have best GPS accuracy when sitting behind a computer in a building, you probably have closer to 30-45 meters accuracy. Meaning every recalculation can easily be 10 meters differently.
Your solution would actually be rate-limit on top of using this property. The property will make sure it will not trigger multiple times per second, and then you can, in your own code, rate limit what you do with it.

Using video.js is it possible to get current HLS timestamp?

I have an application which is embedding a live stream in it. To cater for delays I'd like to know what is the current timestamp of the stream and compare it with the time on the server.
What I have tested up till now is checking the difference between the buffered time of the video with the current time of the video:
player.bufferedEnd() - player.currentTime()
However I'd like to compare the time with the server instead and to do so I need to get the timestamp of the last requested .ts file.
So, my question is using video.js, is there some sort of hook to get the timestamp of the last requested .ts file?
Video.js version: 7.4.1
I had managed to solve this issue, however please bear with me I don't remember where I had found the documentation for this bit of code.
In my case I was working in an Angular application, I had a video component responsible for loading a live stream with the use of video.js. Anyway let's see some code...
Video initialisation
private videoInit() {
this.player = videojs('video', {
aspectRatio: this.videoStream.aspectRatio,
controls: true,
autoplay: false,
muted: true,
html5: {
hls: {
overrideNative: true
}
}
});
this.player.src({
src: '://some-stream-url.com',
type: 'application/x-mpegURL'
});
// on video play callback
this.player.on('play', () => {
this.saveHlsObject();
});
}
Save HLS Object
private saveHlsObject() {
if (this.player !== undefined) {
this.playerHls = (this.player.tech() as any).hls;
// get and syncing server time...
// make some request to get server time...
// then calculate difference...
this.diff = serverTime.getTime() - this.getVideoTime().getTime();
}
}
Get Timestamp of Video Segment
// access the player's playlists, get the last segment and extract time
// in my case URI of segments were for example: 1590763989033.ts
private getVideoTime(): Date {
const targetMedia = this.playerHls.playlists.media();
const lastSegment = targetMedia.segments[0];
const uri: string = lastSegment.uri;
const segmentTimestamp: number = +uri.substring(0, uri.length - 3);
return new Date(segmentTimestamp);
}
So above the main point is the getVideoTime function. The time of a segment can be found in the segment URI, so that function extracts the time from the segment URI and then converts it to a Date object. Now to be honest, I don't know if this URI format is something that's a standard for HLS or something that was set for the particular stream I was connecting to. Hope this helps, and sorry I don't have any more specific information!

Strava API - accurate longitude and latitude

Does anyone know a way to get the exact longitude and latitude for an activity from the strava api using a get request?
I'm trying to integrate the strava api with google maps and I'm trying to build an array with the appropriate long/lat locations, but the https://www.strava.com/api/v3/athlete/activities?per_page=100... request is only returning longitude and latitudes rounded off like: start_longitude: 2.6.
I've found a "hacky" way of retrieving the start coordinates by looping through results and then sending off another request within the loop, although this is sending WAY too many requests. - below is a snippet of my request:
// start request
$.get( "https://www.strava.com/api/v3/athlete/activities?per_page=100&access_token=ACCESSTOKEN", function (results) {
// loop through request
for (i = 0; i < results.length; i++) {
if(results[i].type === 'Run') {
// add an element to the array for each result
stravaComplete.push(true);
$.get( "https://www.strava.com/api/v3/activities/"+ results[i].id +"?per_page=5&access_token=ACCESSTOKEN", function (runs) {
if(typeof runs.segment_efforts[0] != "undefined"){
var runLatitude = runs.segment_efforts[0].segment.start_latitude;
var runLongitude = runs.segment_efforts[0].segment.start_longitude;
stravaActivityList.push({"lat": runLatitude, "lng": runLongitude});
}
// remove the element from the array
stravaComplete.pop();
// if all the elements have been removed from the array it means the request is complete
if(stravaComplete.length == 0) {
// reinitialize map
initMap(stravaActivityList);
}
});
}
}
});
Any guidance would be great. Thanks.
It's not clear if you need coordinates of start points only, or for the whole activity and what accuracy is required.
Response to query https://www.strava.com/api/v3/athlete/activities includes a field map => summary_polyline from which you should be able to extract coordinates of the whole (although simplified) activity. You can also use this polyline to display it in google maps.
If you, however, need even better accuracy you need to retrieve every activity and use map => summary_polyline or map => polyline fields.
To get full data streams should be used
Use summary_polyline[0] and summary_polyline[-1] (Ruby) instead of rounded values. See this code from Slava for an example.

How to debounce a signal in QML?

I have a few properties that have change handlers that request a repaint of a canvas. This works fairly well, but I would like to debounce the signal because a user can only see a limited number of refreshes and some of the data items can change quite frequently. This causes far more refreshes than the user can see and reduces how responsive the UI is.
I have looked at debouncing the signal in javascript (there are examples on the web for how to do that) and tie it in to QML, but I haven't figured out how to get QML and javascript to work together in that way yet.
I would love to see something like the following:
function rateLimitedRefresh(){
// magic to limit to 30 frames per second
canvas.requestPaint()
}
onValueChanged: {
rateLimitedRefresh();
}
With the requestPaint method only being called on the canvas a maximum of 30 times per second.
I used a modification of Mertanian's answer. This modification enforces the frame rate limit at a per frame level as opposed to a per second level.
property var limitStartTime: new Date()
function rateLimitedRefresh(){
// magic to limit to 30 frames per second
var now = new Date();
if (now - limitStartTime >= 32) {
limitStartTime = now
canvas.requestPaint()
}
}
How about something like this:
property var limitStartTime: new Date()
property int refreshesThisSecond: 0
function rateLimitedRefresh(){
// magic to limit to 30 frames per second
if ((new Date()) - limitStartTime >= 33) {
limitStartTime = new Date(limitStartTime.getTime() + 33)
canvas.requestPaint()
}
}
onValueChanged: {
rateLimitedRefresh();
}