Infrared as watermark that can be detected by camera even in daylight

AI Thread Summary
Infrared can effectively serve as a watermark for still images and videos in dark environments, but challenges arise in daylight conditions. To enhance visibility in bright settings, users are exploring methods to increase the brightness of infrared rays without placing LEDs behind the image. Current attempts using multiple infrared LEDs have not yielded satisfactory results, possibly due to absorption by the canvas or low reflection intensity. Adjusting the angles of the infrared sources or using glass surfaces may improve reflection and visibility. Overall, further experimentation with materials and positioning is needed to optimize infrared watermarking in various lighting conditions.
makovx
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Infrared works perfectly fine as a watermark on still images (infrared LEDs put at the back of the image) and even videos when the surrounding is dark.

Is there a way to make it more noticeable even in broad daylight?

And let's say, if my surrounding is dimmer and I want to obscure still-images without putting infrared LEDs at the back, but projecting the beam in front of the image, is there a way to make the infrared rays brighter? I tried using 4 flashlights/spotlights-style with 12 IrLEDs each but the image is still not blocked.
 
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makovx said:
Infrared works perfectly fine as a watermark on still images (infrared LEDs put at the back of the image) and even videos when the surrounding is dark.
Very interesting. :wink:
And let's say, if my surrounding is dimmer and I want to obscure still-images without putting infrared LEDs at the back, but projecting the beam in front of the image, is there a way to make the infrared rays brighter? I tried using 4 flashlights/spotlights-style with 12 IrLEDs each but the image is still not blocked.
It sounds as though the IR is being largely absorbed by the canvas (or whatever), with little reflected? It might be possible to fiddle with angles, aiming the sources so that reflection would be towards where any pirate camera was likely to be positioned, but it might be a lost cause if reflection is diffuse and of low intensity. If you were dealing with paintings or photos, and were able to place them behind glass, investigate whether you can get better reflections off the glass surface. Or maybe there's a transparent coating that can be applied to glass to increase its reflection of IR?

Good luck with your photographic enterprise.
 
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