I'm surprised how poor the video downlink is on Artemis II. I see constant UV corruption even when the bit errors corrupt a full slice.

April 02, 2026 - 23:56 UTC

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TDRS seems to be showing it's age eh?
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I would bet NASA people have noted it as well and will want it improved by the third launch. It isn't remotely a priority now I would assume. But No bucks if there's No Buck Rogers.
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yea, it's truly shit, we had better overall in analog back in '72
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I wonder if they can send a good old fashioned NTSC feed lol
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It would fail in less offensive ways. :)
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They were really nice for a bit, I think they are having some issues with them. Hashtag planning mission. I guess the crew have cameras though?
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UltraViolet?
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It's the color encoding portion(UV) of a YUV macroblock in mpeg style encoders. The luminance (Y) usually gets most of the bits dedicated, because the eye is sensitive to luminance changes and color gets cut by 1/2 or 1/4
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I am sorry we have gotten so spoiled with Space-X's wonderful videos and downlink.
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Yeah. They know the importance of packing a few more bits in their downlinks for "marketing" reasons.
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Any idea what bitrate is allocated to video in the downlink multiplex @destevez.net ? Does everything have FEC? I’ve only seen a little bit of video @jeriellsworth.bsky.social but I see what you mean. I wonder if the encoder is directly generating the artifacts
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Would be cool to know the specs

When I did the telemetry encoding for Astra #1, video was a nice to have if we could wedge it in before launch. Tried to convince the person configuring the encoders to set very small slices. "Hey, I designed encoders" - Ignored - We didn't get many good frames back
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I haven't attempted to get my hands on some Artemis II IQ data yet (partly because T16 is sucking my life 😆). I suspect it is the same system as Artemis I, which had everything as 1/2 LDPC encrypted with SDLS. So we can't look into what share of the multiplex each service gets.
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But what if the errors are IN the error correction code?
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that and the toilet breaking is a glitchy metaphor on the state of the country
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They're using the new deep space communication system starting tomorrow. It streams in 4K. They're not worried about putting on a show right now, it's a brand new spacecraft and entertainment isn't the priority. Making sure they're not going to die is.
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I meant constant UV corruption even when the slice isn't corrupted.
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Speculation on my part, but maybe this was caused by the Van Allen radiation belts and not UV? The Van Allen belts range from about 1000-12,000 km from Earth and SpaceX rockets max out at about 600km.
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They're in space
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