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This is the establishing shot for my short film “Keep Your Feet on the Ground”:

Unfortunately, the consumer camcorder I used had no way to turn off the autoexposure feature of the camera, so as the camera pans down, the roof overexposes to white and the shadows under the eaves drop to black.  After a couple failed experiments, I was able to correct the shot.  Here’s the final version:

My first whack at this was just to try to color correct it.  But where the roof is exposed to white, you can’t color correct lost detail back into that area.  So since this shot was almost a nodal pan, with no action other than the camera movement, I decided I could create a panorama in Photoshop and then fake the camera move in Shake.  This is what I did.

1) I stitched together the best parts of several frames into on Panorama.  (Details on this step can be found in several tutorials across netland, so I’ll just illustrate the process with a simple, useless diagram.)

Some of the frames I used to assemble the panorama.

Some of the frames I used to assemble the panorama.

2) Next, I imported the panorama into Shake.  After fiddling with image brightness, I noticed some mistakes I made when stitching the images together, so I Quickpaint-ed them away.

3) I then added the camera movement using a Pan node.  This took some tweaking to get smooth camera movement and avoid looking off the edges of the panorama.

4) Now this isn’t a normal shot. The last frame of this pan is the first frame of a camera dolly in to the window. So the last frame of the shot couldn’t be changed from the original. I forgot that when I was making the panorama, and had painted all over the bottom part of the panorama. So I had to remake the panorama, being careful not to touch the bottom part this time.

5) The shot looked pretty good at this point, but I noticed the background looked like it should be warping a bit as the camera moved to better match the feel of the original shot. So I added a Lens Warp node. While it improved the shot, it also created several problems. It warped some of the panorama edges into view, and affected that last frame of the shot again.

6) I got around affecting the last frame by fading out the kappa value in the Lens Warp node over time:

Here you can see I faded the Lens Warp kappa value over time.

Here you can see I faded the Lens Warp kappa value over time.

7) To fix the edges coming into view caused by the Lens Warp node, I AGAIN had to remake the panorama in Photoshop, this time cloning in extra sky and bricks on the edges to make things work. (That’s the third time, for those of you not counting.)

The Completed Panorama

The Completed Panorama

8 ) Since the panorama isn’t video, the shot was missing video noise like a real video clip would have. I used a Film Grain node to analyze the sky on the original clip, replicate that noise pattern, and applied it to my panorama pan. Then I decided it didn’t look right, spent about an hour manually fiddling with the values, compared my manual film grain to the original clip, and decided the Film Grain analysis was way better than my poor attempts. Trust the Film Grain node analysis.

9) Finally, just to make SURE that the final frame matched up with the original footage, I actually spliced the panorama shot and the original clip together, making the original clip visible on the last frame. Ops OK. That means everything looked good, yo.

Here's the complete shake tree I used to create the shot.

Here's the complete shake tree I used to create the shot.

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During my playful experiments with Fourier Transforms, I discovered that you can overlay an image on top of a Fourier transformed image, and freely convert back and forth from Fourier to regular space. Each transform would descramble the previously FFT’d image. So in short, you can hide the FFT of one image in another image.

Here’s the message I want to hide:

The Secret Message!

The Secret Message!

I’ve put it in the bottom half of the picture so it will still be intelligible after being transformed. Here’s the FFT of my secret message:

The Fourier Transform of My Secret Message

The Fourier Transform of My Secret Message

My first test overlaid the FFT over a color wheel, but it’s still a bit obvious:

The Secret Message overlaid on a test image.

The Secret Message overlaid on a test image.

If we scroll the FFT over to the corners and scale down the brightness, it’s much harder to spot when overlaid with the zucchini-in-a-bottle image:

The secret message offset to hide it better, overlaid on a normal photo.

The secret message offset to hide it better, overlaid on a normal photo.

You can barely spot it. Some information is lost when the image is saved in the .tif format, but after we scale the brightness back up, we get this:

The actual use decoded message (rescued from a zucchini-in-a-bottle)

The actual use decoded message (rescued from a zucchini-in-a-bottle)

Here’s my whole shake tree for both the test image and the final masterfully masterfool zucchini-hiding-a-secret image. Cheers!

Lossless Shake Message Tree

Lossless Shake Message Tree

Masterfool Zucchini Secret Message Shake Tree

Masterfool Zucchini Secret Message Shake Tree