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Comment by dmurray | Hacker News Reader

Last night I downloaded a TV episode and played it in VLC. 30 seconds in, the power failed. Fine, it's an old laptop I'm using as a media server, battery is long dead - this never happened before but maybe something is loose. I checked the power supply and restarted it. It failed again at the same point in the video, and again a third time. Something about that video causes my laptop to die.

I turned it off and went to bed. Maybe I'll troubleshoot it today. But I'd love to understand what could have happened. The closest thing I know of is the Janet Jackson video that could crash hard drives [0]. In this case the sound was playing on a different device (my TV) so I don't think it's the same explanation.

For extra weirdness, the episode was Black Mirror S7E01. Exactly the kind of thing the creators would like to build into a Black Mirror episode.

[0] https://devblogs.microsoft.com/oldnewthing/20220816-00/?p=10...

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Dying on the exact same frame, or just generally in the same spot?

In the case of the latter my first thought would be thermals. Different video codecs have significantly different decoding costs, and may also stress different parts of your system. You could check for that by playing that same video but not starting at the beginning and see if it's the same duration. Or jump to just before it dies and see if it plays through.

If by "downloaded" you mean The High Seas, those who provision the high seas are often on the cutting edge of using codecs with every last feature turned on to make the videos smaller to squeeze every last bit out of the encodings that they can, which can make them unusually expensive to decode. Or so I've heard.

I didn't get to dig much further into it, but for those of you who suggested ideas:

- not always the same frame. The first three failures were within seconds of each other, possibly the same frame. I tried again the next night and it got through that part of the video, but crashed a minute later - I was able to play the video using a different app (Ubuntu's built-in Videos app from an old Ubuntu release, maybe 20.04)

Some of these video codecs have pathological cases that might be maxing out your video while doing the decoding. If you're only using it as a media server, that might exceed the (possibly age-degraded) capacity of your power supply. Replacing the power supply might help in that case.

It's also possible that something in a particular frame is triggering a bug in your driver and crashing that way. In that case, your best bet might be to transcode the video to a different codec or something.

Maybe your particular video download is from an entirely trustworthy source, but it's not unheard of that untrustworthy folks will modify a file with the intent of causing this to happen.

If you manage to find out what the cause is, I'd love to hear it.

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