• 14 Posts
  • 372 Comments
Joined 3 years ago
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Cake day: June 22nd, 2023

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  • So find the places where the bitrate changes and decode and analyze those frames. Outdoors, true, leaves blow around, there is wildlife etc. A harder problem. I was thinking more of an indoor security camera. As for examining the bit rate, I guess it depends on the encoding, but e.g. in .mp4 there is a “key frame” every so often and then a bunch of delta frames, and if stuff is changing too fast iirc the key frames become more frequent. But I believe there is a fast way to scan for them, that is needed for fast forwarding in video.


  • I have to wonder if there’s a faster way than literally decoding the video and analyzing the decoded frames, if that’s how you’re doing it with ffmpeg. Video compression revolves around motion estimation so maybe it’s possible to just scan the file and find frames where the motion vectors (the data saying how the stuff in the picture is changing at a given frame) suddenly get larger. I assume this is for something like a security video that usually shows a static picture, and OP wants to flag when someone enters the room. In that case there will be almost no motion most of the time, and suddenly there will be some.




  • Meh, it’s sort of an empty gesture, as discussed in the HN thread. The “competitor” is a somewhat-compatible Teensy 3 clone that uses a different processor with roughly similar cpu performance. It doesn’t compete with the much faster Teensy 4 which is the only model that PJRC currently sells. And these types of boards aren’t generally about CPU performance anyway. If you want fast computing, get a Linux board or similar. These boards are about stuff like analog i/o.








  • I’d DIY it (maybe with FreeNAS, about which I know nothing) instead of buying a proprietary NAS in a box. What’s the point of self-hosting if you’re going to be at the mercy of someone else’s software anyway? If you’re DIY’ing, there are 3.5" drive enclosures with soundproofing stuff in them that should keep the drive pretty quiet. Or if you can afford enough SSD’s for your storage requirements, then use those.