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Recently, we had a problem with people doing donuts in our parking lot. We have the cameras in place but the night vision camera couldn’t see the license plate because of the lights that illuminate the plate. It looked like a blank, white rectangle where the license plate should be. ​

Is there anything I can do in Photoshop or something of the sort in order to get the plate numbers?

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    \$\begingroup\$ I'd say it's on topic here. Is it possible that you upload an image? Also, are they raw, jpg...? \$\endgroup\$
    – OnBreak.
    Sep 4, 2018 at 13:56
  • \$\begingroup\$ I'd be shocked if images from a parking lot night vision camera are raw format — in fact, it's probably stills from a compressed video stream. \$\endgroup\$
    – mattdm
    Sep 4, 2018 at 14:41
  • \$\begingroup\$ @mattdm wait, you mean you can't just "ENHANCE"??? youtube.com/watch?v=KiqkclCJsZs \$\endgroup\$
    – OnBreak.
    Sep 4, 2018 at 15:11
  • \$\begingroup\$ @Hueco I have the MP4 video and can take screenshots of them. is there a specific image format that would be best for this type of thing \$\endgroup\$
    – Josh
    Sep 4, 2018 at 17:04
  • \$\begingroup\$ I'm not the best judge of the best way to grab data from an mp4. I don't think a screen grab will provide for you. Perhaps ask for the best way to modify the mp4 in a similar way as my curves example over at Video.SE? \$\endgroup\$
    – OnBreak.
    Sep 4, 2018 at 17:07

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Like Orch said, once something is blown out, there's generally nothing there to recover. But, give this a try and see how it works.

I created a pure white image and then lowered down from pure white by just a tad to create this square:

enter image description here

As you can see, the square is there, but just barely. Open an image editor, Pixlr in this case (online and free), or photoshop, or gimp...

Use the Curves tool. This tool adjusts the image so that any given value is modified. By dragging it as I did, I'm telling Pixlr to darken every single pixel that is not pure white:

enter image description here

As you can see, the barely there rectangle is now sticking out. Hopefully, if there is any data in the plate, this method will reveal it.

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  • \$\begingroup\$ is there a "best" image format for this type of thing? \$\endgroup\$
    – Josh
    Sep 4, 2018 at 17:10
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    \$\begingroup\$ @Josh Any non-destructive format should do. If the picture is JPG, depending on the compression setting, you might have lost the fine color-differences between "completely white" and "almost completely white". \$\endgroup\$
    – Lothar
    Apr 2, 2019 at 22:29
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Generally recovering detail in overexposed areas of a photo doesn't work well (especially if it's not in a raw format), but you might as well give it a shot. Open the picture in some photoediting software and move the sliders for exposure and highlights down until you (hopefully) see something.

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