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Okay, how big is the video and what exactly was the bandwidth? Can't understand why they won't put the basics in the article. So I illegally downloaded the vi

Okay, how big is the video and what exactly was the bandwidth? Can't understand why they won't put the basics in the article. So I illegally downloaded the video from YouTube; it appears to be 2657084 bytes, so 2657084/3.5 is 759166 bytes per second or 6073328 bits or 5.8 megabit per second. Reporting that as a maximum rate of 50 megabit seems ... a little "Comcastic". Or am I missing something? Update: I see another article calling it a 175 megabit transmission so if that took 148 seconds that's an average rate of 1.2 megabit. It's a mystery to me why average throughput is just not interesting to the author of the original article. And presumably the downvoting I'm getting is from a similar sense of vapid apathy about intriguing detail.

CountHackulus 12y ago
They said that the video was transmitted repeatedly over the course of the test.
dozy 12y ago
conceivable that the 3.5 seconds includes some overhead related to getting the thing powered up and pointed in the right direction. Also conceivable that it peaked at 50mbps for just a moment. I'll also throw in that whatever protocol they're using...I'm guessing it's not bit torrent over HTTP over TCP :)...has overhead as well to account for errors and OUTER-SPACE related nuances! anyways I'm willing to give them the benefit of the doubt.
maxerickson 12y ago
I wouldn't expect the bits coming down from YouTube to be a meaningful representation of what they transmitted. This page describes the mission goal as 10 megabits-per-second or higher, I guess they aren't making that up: http://www.nasa.gov/mission_pages/station/research/experiments/861.html http://www.nasa.gov/mission_pages/station/research/experimen...
- woodchuck64 12y ago
  Why wouldn't YouTube be meaningful? It would make sense for the video to be stored and transmitted as h264 and then uploaded as is to YouTube. I doubt YouTube recompresses h264.
  - maxerickson 12y ago
    It's certainly possible that it is of similar size. For it to be meaningful, I would want it to be overwhelmingly likely that it was the original.
  - burkaman 12y ago
    Because the version they put on Youtube is probably not the exact version they received from the ISS. The article repeatedly described the video as HD, and the Youtube version isn't. And if you aren't willing to take NASA at their word, it's not that hard to imagine how multiple versions of a video end up getting passed around an organization, and the one that gets uploaded is compressed for whatever reason.

CountHackulus 12y ago

They said that the video was transmitted repeatedly over the course of the test.

dozy 12y ago

conceivable that the 3.5 seconds includes some overhead related to getting the thing powered up and pointed in the right direction. Also conceivable that it peaked at 50mbps for just a moment. I'll also throw in that whatever protocol they're using...I'm guessing it's not bit torrent over HTTP over TCP :)...has overhead as well to account for errors and OUTER-SPACE related nuances! anyways I'm willing to give them the benefit of the doubt.

maxerickson 12y ago

I wouldn't expect the bits coming down from YouTube to be a meaningful representation of what they transmitted. This page describes the mission goal as 10 megabits-per-second or higher, I guess they aren't making that up: http://www.nasa.gov/mission_pages/station/research/experiments/861.html http://www.nasa.gov/mission_pages/station/research/experimen...

woodchuck64 12y ago
Why wouldn't YouTube be meaningful? It would make sense for the video to be stored and transmitted as h264 and then uploaded as is to YouTube. I doubt YouTube recompresses h264.
- maxerickson 12y ago
  It's certainly possible that it is of similar size. For it to be meaningful, I would want it to be overwhelmingly likely that it was the original.
- burkaman 12y ago
  Because the version they put on Youtube is probably not the exact version they received from the ISS. The article repeatedly described the video as HD, and the Youtube version isn't. And if you aren't willing to take NASA at their word, it's not that hard to imagine how multiple versions of a video end up getting passed around an organization, and the one that gets uploaded is compressed for whatever reason.