Let's take this sea landscape:
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Select the sea using Pen Tool. Choose Gradient Tool, take the foreground colour as white, background colour as black. Make the gradient filling down-top. Then select the sky, desaturate it, make Auto Contrast. Then use the semi-transparent gradient filling with 80% opacity. Make Auto Contrast again. Draw the seashore with a black colour. This is our depth map:
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| gradient filling the sea | semi-transparent gradient filling the sky with 80% opacity | drawing the seeshore with a black |
This is the anaglyphic image:
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This is the animated image:
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