There is a program at enounce.com that it will increase the play speed of a video in a browser. I think that 95% of videos on the internet run on flash therefore this tool can be useful. I am wondering how that program was created. Maybe they modify the html source in the browser? perhaps it looks for the swf video playing on your browser and it injects some JavaScript on that html element to increase the speed. I been researching on Google and I think it is possible to alter the playback speed of a video with JavaScript. If it is not modifying the html page then it will be nice to at least know how this can be achieved. Also if a video plays on your browser it has to be saved somewhere in your computer I believe. That's why you can seek back and forth once the video finished downloading. why is it that it is almost impossible to find it and the only way of getting that video will be by capturing the packages with a package sniffer? anyways that is not my question I am just really curious on how that program achieves doing what it does. it speeds up everything even Pandora songs.
MySpeed seems to intercept the media stream coming from the server into the Flash player that sits in your browser. It changes the speed on the fly, and sends the result to the Flash player.
PS: If you need to control the playing speed of your own videos I recommend looking into the VLC Browser Plug-in, or the QuickTime player, which also has very good speed control features (from Javascript). Or you could use the HTML5 <video> tag.
Afaik, Flash-based players like Longtail/JWPlayer and Nonverbla don't have very good support for this.
Related
I'm trying to find a way to make a program similar to after effects or blender in the browser, in the sense of developing certain animations etc., and compiling the animations and keyframes info a video, preferably frame-by-frame
Using the built in methods of the canvas and media recorder, I have yet to find a way to process a video by inserting one frame at a time, to a set framerate, usually the media recorder just records live in real time, it doesn't seem to be meant for frame by frame rendering, and also the canvas is limited in the sense of being too slow or unreliable to consistently get the image from it using either toDataURL or glGetPixels etc.
Is there a way to process videos in JavaScript without using the canvas at all?
Meaning, instead it would just generate the image data and display it as an img tag, or even a real time low quality video encoding and streaming, on the client side, and attach the stream to a video tag somehow, or perhaps the canvas could be used for development of the keyframes etc. but the actual processing would be done by scratch, is this the best way to go about this? And if so, how can it be done?
Is there any way to have two or more (preferably three) html5 < video > tags playing simultaneously and to be in perfect sync.
If I have let's say three tiles of one video and I want them to appear in browser as one big video. They need to be perfectly synchronized. Without even smallest visual/vertical hint that they are tiled.
Unfortunately I cannot use MediaController because it is not supported well enough.
I've tried some workouts, including canvases, but I still get visual differentiation. Has anyone had any similar problem/solution?
Disclaimer: I'm not a video guy, but here are some thoughts anyway.
If they need to be absolutely perfect...you are fighting several problems at once:
A device might not be powerful enough to acquire, synchronize and render 3 streams at once.
Even if #1 is solved, a device is never totally dedicated to your task. For example, it might pause for garbage collection between processing stream#1 and stream#2--resulting in dropped/unsynchronized frames.
So to give yourself the best chance at perfection, you should first merge your 3 videos into 1 vertical video in the studio (or using studio software).
Then you can use the extended clipping properties of canvas context.drawImage to break each single frame into 2-3 separate frames.
Additionally, buffer a few frames you acquire on the stream (this goes without saying!).
Use requestAnimationFrame (RAF) to control the drawing. RAF does a fairly good job of drawing frames when system resources are available and delaying frames when system resources are lacking.
Your result won't be perfect, but they will be synchronized. You will always have to make the decision whether to drop or delay frames when system resources are unavailable, but at least the frames you do present will be synchronized.
As far as I know it's currently impossible to play HTML5 video frame-by-frame, or seek to a frame accurate time-code. The nearest seek seems to be precise to roughly 1-second.
But you can still get pretty close using the some of the media frameworks:
Popcorn.js library made for synchronizing video with content.
mediagroup.js another library used to add support for mediagroup attributes on HTML5 media elements
The only feature that allowed that is named mediaGroup and it was removed from Chrome(apparently for not being popular enough). It's still present in WebKit. Relevant discussion here and here.
I think you can implement you own "mediagroup"-like tag using wasm though without DOM support it may be tricky.
Is there a way to change the playback speed of audio in the browser? What is best to accomplish this task, html5 audio, or flash, or something else? Are there any specific libraries that would help with this?
Use the Web Audio API.
In the following code I answered your other question.
best way to loop audio in the browser?
Modify the code in my answer above as follows for a playback speed example.
Right below
source.loop = loopOnOff;
add
source.playbackRate.value = 1; // change number to between 0.10 to 10 (or larger/smaller) to test.
You can also run the html audio tag through the web audio api and add effects processing.
Interesting question there,
HTMl5 will have player speed control will have speed control..
A couple of noteworthy upcoming features are playbackRate and defaultPlaybackRate. As you can probably imagine, these fellas let us alter the speed and direction of playback. This functionality could be used for fast-forward and rewind functions or perhaps to allow users to tweak the playback speed so they can fit more podcasts into their day.
audio.playbackRate returns 1 at normal speed and acts as a multiple that is applied to the rate of playback. For example, setting playbackRate to 2 would double the speed, while setting it to -1 would play the media backwards.
audio.defaultPlaybackRate is the rate at which the audio will play after you pause and restart the media (or issue any event for that matter).
Flash Player may help( but it will be customized one you may create, with stream buffer, you need to define the player speed once buffer has the content to play.
Sound easy but will take a lot effort,
Refer VLC opesource for better Idea, its documented with ffmpeg which works with Audio,
and works with client software, in browser ti will be heavy, refer Just to have idea.
I hope this may help :)
I've been working at a startup for some time and nearly have a product ready to ship for a certain platform that's a very high quality html5 javascript game. Everything was made in html5 from using canvas and even the audio+video elements. Now after we sent in our product for review they responded by telling us that the audio wasn't finished yet on their end and to convert our audio to swf and use flash for it instead.
The problem is I'm not a flash developer, I've never touched flash and only worked in javascript and we're already behind schedule. I don't have the slightest clue how I'd go about using swf files to play audio in a non obtrusive manner for an action game. Especially since our game is no simple game with a simple sound track. There's several tracks of audio an opening video, and dozens of sound effects for weapon clashes and such.
Is there anyone that can give me some tips or share some links on how I could go about using swf for audio for lots and lots of sounds without it making a mess of things and the dom?
Thanks alot
This post should help you with calling flash functions from javascript. http://painteddigital.com/2008/calling-flash-as3-functions-from-javascript/ Pretty easy.
Playing audio from flash is very simple too. Just take a look at the documentation for the Sound class.
I'm building a video for my website with HTML5. Ideally, I'd have only one silent video file, and five different audio tracks in different languages that sync up with the video.
Then I'd have a button that allows users to switch between audio tracks, even as the video is playing; and the correct audio track would come to life (without the video pausing or starting over or anything; much like a DVD audio track selection).
I can do this quite simply in Flash, but I don't want to. There has to be a way to do this in pure HTML5 or HTML5+jQuery. I'm thinking you'd play all the audio files at 0 volume, and only increase the volume of the active track... but I don't know how to even do that, let alone handle it when the user pauses or rewinds the video...
Thanks in advance!
Synchronization between audio and video is far more complex than simply starting the audio and video at the same time. Sound cards will playback at slightly different rates. (What is 44.1 kHz to me, might actually be 44.095 kHz to you.)
Often, the video is synchronized to the audio stream, but the player is what handles this. By loading up multiple objects for playback, you are effectively pulling them out of sync.
The only way this is going to work is if you can find a way to control the different audio streams from the video player. I don't know if this is possible.
Instead, I propose that you encode the video multiple times, with the different streams. You can use FFMPEG for this, and even automate the process, depending on your workflow. Switching among streams becomes a problem, but most video players are robust enough to guess the byte offset in the file, when given the bitrate.
If you only needed two languages, you could simply adjust the balance between a left and right stereo audio channel.
If you're willing to let all five tracks download, why not just mux them into the video? Videos are not limited to a single audio track (even AVI could do multiple audio tracks). Then syncing should be handled for you. You'd just enable/disable the audio tracks as needed.
It is doable with Web Audio API.
Part of my program listens to video element events and stops or restarts audio tracks created using web audio API. This gives me an ability to turn on and off any of the tracks in perfect sync.
There are some drawbacks.
There is no Web Audio API support in Internet Explorers except for Edge.
The technique works with buffered audio only and that's limiting. There are some problems with large files: https://bugs.chromium.org/p/chromium/issues/detail?id=71704