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Ingenuity's Shadow During Third Flight shows the GIF below which is made from cropped bits from several downward-looking images from Ingenuity's navigation camera, stretched so that the ground is fixed and the helicopter's shadow moves. It shows several interesting features.

The caption includes:

The shadow of NASA’s Ingenuity Mars Helicopter can be seen in this animated GIF composed of images taken by its black-and-white navigation camera during the rotocraft’s third flight, on April 25, 2021. The camera, which tracks surface features below the helicopter, takes images at a rate at which the helicopter’s blades appear frozen in place, despite making 21 full rotations in-between each image. At full speed, the blades spin at 2,537 rpm. The images are aligned entirely using Ingenuity's on-board position tracking system highlighting the stability and accuracy of the navigation algorithm.

The GIF has been cropped to fill the frame, and the contrast has been increased so it’s easier to see; the frame rate has also been sped up. An uncropped version is included to show what the view from the camera normally looks like. An additional visualization shows how the star shape of the images in the original video is created by the fisheye lens on the navigation camera.

But I don't see said uncropped version anywhere. Does anyone know where/if it's been posted?

Question: Where is the uncropped version of this cool Ingenuity navigation camera GIF?

Ingenuity's Shadow During Third Flight, cropped version

You can also see the shadow hiding/opposition surge effect around ingenuity's shadow. Cool!

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  • $\begingroup$ If I understand the caption correctly, this has been created by Ingenuity itself. I.e. it's likely the raw images don't exist at all. $\endgroup$ – asdfex May 2 at 9:04
  • $\begingroup$ @asdfex that will be interesting if it crops, does affine transforms and builds GIFs all while flying on Mars! Thanks for catching the missing link. $\endgroup$ – uhoh May 2 at 9:16
  • $\begingroup$ @uhoh: it's not that implausible that it does this: it has a lot more computational power than anything else on Mars (than everything else on Mars!) and it's connected to Perseverance by a link which makes wet string look rather high-bandwidth. So it might make sense to process stuff locally. OTOH I'd kind of want the raw data if I could have it, even if I could only get it much later. $\endgroup$ – user21103 May 2 at 13:18
  • $\begingroup$ @tfb youtu.be/Sr9yk5eBL1M the system extracts features and tracks them. (something like optical flow) It doesn't crop and morph a long series of images to match each other and to look nice, that's computationally much more expensive and after it's done it can't use that anyway. It works in a much smaller parameter space; the pixel coordinates of the green dots in the video. This GIF was done by humans for humans to enjoy and to trigger Stack Exchange questions. $\endgroup$ – uhoh May 2 at 14:18
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    $\begingroup$ @uhoh, yes, I agree with all that: this video was made for people, not for navigation, clearly. What I meant is that it's possible (though, I think, unlikely) that the image was processed on-board Ingenuity (not while it's flying of course!) because it was more efficient to do that and transmit only the processed image rather than all the frames given bandwidth constraints. I don't think this is likely but it's a possibility. $\endgroup$ – user21103 May 2 at 14:43

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