Around the same time I posted a writeup analyzing the disparity in the airliner satellite video pair, u/Randis posted this thread pointing out that there are matching noise patterns between the two videos. When I saw the screenshot I thought it just looked like similarly shaped clouds, but after more careful analysis I agree that it is matching sensor noise.

The frame that u/Randis posted is frame 593. This happens in the section between frame 587 through 747 where the video is not panning. Below is a crop from the original footage during that section, at position 205,560 and 845,560 in a 100×100 pixel window (approximately where u/Randis drew red boxes), upsampled 8x using nearest neighbor, and contrast dialed up 20x.

Another way to see this even more clearly is to stack up all the images from this section and take the median over time. This will give us a very clear background image without any noise. Then we can subtract that background image from each frame, and it will leave us with only noise. The video below is the absolute difference between the median background image and the current frame, multiplied by 30 to increase the brightness.

The fact that the noise matches so well indicates that one of the videos is a copy of the other, and it is not a true second perspective.

If this is fake, this means that a complex depth map was generated that accounts for the overall slant of the ocean, and for the clouds and aircraft appearing in the foreground. The rendering pipeline would be: first 3D or 2D render, then add noise, then apply depth map. It would have been just as easy to apply the noise after the depth map, and for someone who spent so much care on all the other steps it is surprising they would make this mistake.

If this is real, there is likely no second satellite. But there may be synthetic aperture radar performing interferometric analysis to estimate the depth. SAR interferometry is like having a Kinect depth sensor in the sky. For the satellite nerds: this means looking for a satellite that was in the right position at the right time, and includes both visible and SAR imaging. Another thread to pull would be looking into SAR + visible visualization devices, and see if we can narrow down what kind of hardware this may have been displayed on.

What would the depth image look like? Presumably it would look something like the disparity video that we get from running StereoSGBM, but smoother and with fewer artifacts.

Another “tell” that just came up, u/JunkTheRat noticed that the text on the right distorts while the text on the left stays still.

Here is a visualization showing this effect across the entire video.

At the top left is the frame number. The top image is the left image telemetry. The second image is the right image telemetry. The third image is the absolute difference between the left and right. The fourth image is the absolute difference with brightness increased 4x.

The text is clearly slanting and jumping. This indicates the telemetry data on the right was not added in post, but it is a distorted version of the video on the left.

This led me to another question: what is happening with the mouse cursor? If this is real, I would expect the mouse to be overlaid at a consistent disparity, so it appears “on top” of all the other stuff on the screen. If the entire right image, including the cursor, is just a distortion of the one on the left, then I would expect the mouse to jump around just like the text.

But as I was looking into this, I found something that is a much bigger “tell”, in my opinion. Anyone who has set a single keyframe in video editing or VFX software will recognize this immediately, and I’m sort of surprised it hasn’t come up yet.

The cursor drifts with subpixel precision during 0:36 – 0:45 (frames 865-1079).

Here is a zoom into that section with the drifting cursor, upsampled with nearest neighbor interpolation and with difference images on the bottom. Note that the window is shifted by 640+3 pixels.

Note that the difference image changes slightly. This indicates that it is being affected by a depth map, just like the text. If we looked through more of the video we might find that it follows the disparity of the regions around it, rather than having a fixed disparity as you would expect from UI overlay.

But the big thing to notice is how smoothly the cursor is drifting. I estimate the cursor moves 17px in 214 frames, that’s 0.08 pixels per frame. While many modern pointing interfaces track user input with subpixel precision, I am unaware of any UI that displays cursors with subpixel precision. Even if we assume this screen recording is downsampled from a very large 4K screen, and we multiply the distance by 5x, that’s still 0.4 pixels per frame.

This is exactly what it looks like when you are creating VFX, and keyframe an animation, and accidentally delete one keyframe that would have kept an object in place—causing a slow drift instead of a quick jump.

This cursor drift has convinced me more than anything that the entire satellite video is VFX.

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