Ask HN: How is Netflix able to prevent screenshots on Chrome?

8 points by the42thdoctor 4y ago ↗ HN

The other day I tried to screenshot a funny frame in a Netflix video to show to a friend and the image came out black. I tried both the `prtsc key` and the `Snipping Tool`. This got me wondering is JavaScript able to interfere with the built-in OS printscreen function ?

I was using Chrome on a Windows 10 machine, and in the end, strangely enough, I was able to take the screenshot on the Netflix Android app.

5 comments

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amir-h 4y ago ↗

That's probably DRM protected content, it's not Javascript hack but a mecahnism that's built in deeper. A high level overview of how it works on Android is here(the secure texture part):

https://source.android.com/devices/graphics/arch-st#st_vid_p...

I'm not sure what the implementation is on Chrome/Desktop; probably something similar.

[dead] holomorphically 4y ago ↗

Try OBS Studio if you want to do screen capture.

colesantiago 4y ago ↗

The workaround of pointing/recording content using a mobile camera is guaranteed to always work regardless of any flimsy DRM scheme these vendors implement [0].

[0] https://en.wikipedia.org/wiki/Analog_hole

sundvor 4y ago ↗

It's ironic that a lot of efforts spent trying to fight this had the result of steering at least some towards piracy, so as to enable getting the desired content without all these experience degrading anti piracy measures.

schappim 4y ago ↗

Chrome has the Widevine DRM built into it. Since 2017 users cannot disable it.