Show HN: Screen recording with JavaScript

https://mgechev.github.io/jscapture/

by own3r • 12 years ago

87 29 12 years ago

mgechev.github.io

wingerlang• 12 years ago

Chrome Version 35.0.1916.114 OSX 10.9

I get an error then a blank modal. On both buttons. Nothing in the console to tell me more or anything like that.

ioseph• 12 years ago

Chrome 34.0.1847.137m on Win7, getting an alert: "Error, while recording your screen"

eskimobloood• 12 years ago

Seems the app is a test to verify that people don't read the README.

sync• 12 years ago

From the readme:

    Currently the API for screen capturing is supported only by Google Chrome, Canary and Chromium by enabling an experimental flag.

    In order to enable the flag:

    Go to chrome://flags
    Enable - "Enable screen capture support in getUserMedia()"
    Restart your browser

https://github.com/mgechev/jscapture#how-to-use

dshankar7• 12 years ago

Please do not do this.

You should not instruct users to change flags in order to use this. This opens up fairly serious security loopholes as malicious websites can start screensharing without being instantiated by the user.

Instead of using the getUserMedia API directly, you should use Chrome's chooseDesktopMedia API to get a desktop capture source (the screen, a tab, or any application window). The chooseDesktopMedia API is available in Chrome 34+ and can be used to do desktop screen capture/share without asking the user to enable flags.

As of 6 hours ago, the flag (#enable-usermedia-screen-capture) has been removed and will not be present in Chrome 35 Stable. [Ref: https://codereview.chromium.org/270353002 & https://code.google.com/p/chromium/issues/detail?id=347641]

In any case, cool hack!

dshankar7• 12 years ago

Another benefit of using cDM: more visitors to your site would be able to use your app right now instead of posting "Chrome vers. doesn't work" :-)

20% of the world (and likely an even larger percentage of HN users) already have cDM support! [http://caniuse.com/usage_table.php]

gk12• 12 years ago

I was excited about this at first. I don't know of any simple way to record my screen without having to download decade-old software. A web-based solution like this would be amazing... Until I realized I'd have to follow a list of work-arounds just to get it working.

Hoping this is just the first trial run and the next iteration will get this resolved.

randall• 12 years ago

(yo Darshan!)

Correct me if I'm wrong but isn't that api an extension only api?

https://developer.chrome.com/extensions/desktopCapture

cpncrunch3• 12 years ago

It does look like it is only for extensions. Does this mean it will now be impossible for users to use desktop sharing from web apps?

I don't really see the security problem. Right now there is a popup asking if you want to share your screen, and there is also a permanent warning at the bottom of the screen while the screen is being shared. Also it is only available on https sites. What possible security risk is there?

dshankar7• 12 years ago

(Hey Randall! :-)

Yes, it requires an extension and that's the way it ought to be. Explicit user-intent, properly sandboxed.

Allowing any website to arbitrarily capture your entire desktop screen (or any application screen) is an enormous security risk that shouldn't be taken lightly, so an extension seems like the right decision.

thrush• 12 years ago

Even with security risk, this is a bit of a golden egg for automated selenium testing!

MasterScrat• 12 years ago

It would be really nice to be able to record a portion of my browser window, convert the sequence to a GIF and upload it to imgur.

That would make some bug reports much clearer, rather than describing each step.

scraplab• 12 years ago

Yes, this would be brilliant. I'd really like it as an always available app with a hotkey to activate recording, and Dropbox integration for upload + sharing. Even limited to a few seconds it'd be very useful for developing complex UI interactions with a remote team.

gk12• 12 years ago

...convert the sequence to a GIF and upload it to imgur.

I would even pay for a tool like this.

xhrpost• 12 years ago

Trying to think how you could build this. Unless there's some fancy new feature in the browsers, I think you'd have to do something complicated like run WebKit.JS and capture from the canvas output.

petercooper• 12 years ago

It's not browser based but such a thing exists for Windows and OS X: http://www.cockos.com/licecap/

MattBearman• 12 years ago

Shameless plug: My app BugMuncher (http://bugmuncher.com) allows you to submit screenshots with bug reports, without needing any browser plugins or experimental APIs. The ability to take a sequence of screenshots for each bug report is on the road map.

Jonovono• 12 years ago

I am working on a project to do that for the Mac: https://github.com/Jonovono/cutter. I originally wanted to do it in JS for the web but didn't find away. May revisit that now!

hsx• 12 years ago

This is cool but video should scale to screensize. Yes, I do understand that this is more of a proof of concept.

SimeVidas• 12 years ago

Why is Firefox not supported? https://github.com/mgechev/jscapture/issues/5

gcp• 12 years ago

FWIW Firefox for Android supports sharing Tabs via getUserMedia.

frozenport• 12 years ago

"With great power comes great responsibility"

yaronn01• 12 years ago

I recently did something similar with official javascript APIs:

http://s3-us-west-2.amazonaws.com/anigif100/pacman/index.htm...

Show HN: Screen recording with JavaScript

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