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by megous 2030 days ago
Camera can record video, 720p will probably be a limit unless you don't mind lower than 30fps framerate.

Here's my test recording from a few weeks ago: https://megous.com/dl/tmp/vid-720.mp4

You can only encode via CPU for now, and at best you may be able to encode to x264 at the ultrafast profile. (don't remember which one is fastest, but it's the fastest one) Encoding with the fastest available profile just happens to run at 30fps, so it's still not enough to for realtime encoding even via CPU, if you account for the fact that CPU will start throttling soon after you start loading all 4 cores at once to the max.

So I recorded the above by saving raw frames. :)

Video image quality sucks of course. (that frame counter is all white uniform background in reality)
1 comments
jcun4128 2030 days ago
Don't mean to be nosy ha, what is the code you were working on/had on screen? Perhaps not specifics but language/context the grouping seemed interesting. (the indents are insane is it Go/Linux?)

I guess when you say "saving raw frames"... are you saying this video you made was not simple by "push record button, .mp4 comes out"?

Oh the white background comment is about the iso/bad balance?

Anyway thanks this is pretty cool... I just ordered mine so won't be able to play around with it till January.

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megous 2030 days ago
That's part of the C code running on the phone, recording itself. Kinda meta. :)

There's quite a lot of https://en.wikipedia.org/wiki/Vignetting going on. Camera sensors have anti-vignetting circuitry that is supposed to eliminate this, but it needs to be calibrated to each module and maybe even enclosure the module is in.

I recorded this via a C program, but you can do the same via v4l2-ctl command line tool and encode the result with ffmpeg.

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jcun4128 2030 days ago
> That's part of the C code running on the phone, recording itself. Kinda meta. :)

Oh man that's cool. I'm working towards that level (C/C++) but coming from JS/Python where you can pretty much "do anything" it's challenging(typing problems in particular eg. array of assorted things of any length).

Oh interesting about the Vignetting will have to read up on that not familiar with the term.

> ffmpeg

Yeah that's something cool I gotta work with too at some point.

Thanks

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