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Mars images rendered in 4K [video]

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Re: Mars images rendered in 4K [video]

#94
post #67

Earlier quoted context omitted.

At least they're panning at 60fps, decreasing tearing/seizures

How do you get 60fps, it stutters at 30fps for me.

What hardware are you using? Even if your browser is taking advantage of a hardware decoder, older ones may struggle with 4K@60.

Re: Mars images rendered in 4K [video]

#95
post #92

I can't find a comment asking this yet, so I'll do it: where can I get the actual images, not in a video? I'm assuming these images are in the public domain?

Spirit and Opportunity: https://mars.nasa.gov/mer/multimedia/images/ (raw: https://mars.nasa.gov/mer/multimedia/raw/ )

Curiosity: https://mars.nasa.gov/msl/multimedia/images (raw: https://mars.nasa.gov/msl/multimedia/raw-images )

Re: Mars images rendered in 4K [video]

#98

what impressed me more about this video is how earth like an alien world looks like. it may not have vegetation but there's nothing I wouldn't expect to see somewhere on earth.

Devon Island is where many people train to work on Mars missions https://www.youtube.com/watch?v=xzyOdH6OlV0

Re: Mars images rendered in 4K [video]

#99
post #89

Earlier quoted context omitted.

That's exactly what I'm saying, though. Because YouTube (like other streaming services) aggressively compresses both 1080p and 4K, but the 4K version still has a much higher bitrate , watching the 4K stream on a 1080p monitor will be significantly better quality than watching a 1080p stream on a 1080p monitor. I'm not saying you won't see any compression artifacts at all, of course if it's an scene you will. But the…

Yeah, what I'm saying is that because the 4k streams are trying to convey more entropy than the 1080p streams, I've observed that even though their bitrate is higher, the resultant compression effects are far more severe, to the point where the overall experience is better with 1080p, sometimes even if you have access to the full 4k resolution. I've seen similar effects with audio content (after a certain point, incr…

Oh now I understand what you're saying -- that makes sense. It's not what I've observed, but I definitely can imagine how settings for the compression, or what the algorithm concentrates on, could make that happen. I'll have to pay close attention now! And your rationalization probably makes sense -- I read the h.266 codec is supposedly focusing specifically on perception improvements in 4K/8K, so it may be addressing what your'e perceiving specifically.

Funnily enough, this reminds me of what I did with JPEGs on websites when Retina first became a thing. Instead of serving up different assets depending on resolution, I discovered that serving up a 2x resolution JPEG to everyone, with really crappy quality, was superior to serving up 1x with high quality. For 1x screens, blockiness was inherently shrunken because of JPEG's fixed block sizes, and for 2x screens the low quality was harder to perceive because it was at a small scale anyways. How compression interacts with scale/resolution is not a necessarily intuitive thing.

Re: Mars images rendered in 4K [video]

#100

Earlier quoted context omitted.

There is in fact wind. Only ~1% as much air as Earth, but it's sufficient to support phenomena like dust devils. https://science.nasa.gov/science-news/science-at-nasa/2005/1... Of course, it's very weak, so it couldn't push over a spacecraft or building like in "The Martian", but I suspect sands shifts on a very slow timescale. I'm not sure.

There are "dust devils" on Mars: http://www.esa.int/ESA_Multimedia/Images/2018/04/Dust_devil_... .

You just linked to the ESA version of my NASA link :)
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