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I need to recover some badly underexposed video. The video is virtually black with no detail at the moment.

I don't need it to be perfect but I would like some ideas on a process I could follow to recover some of the image. It will be OK if it's grainy and I don't really mind if the white balance is off.

It was shot on a DSLR using f11 ISO100.

If anyone could suggest a good program (free or trial) I could use and a process to recover something out of it then that would be fantastic.

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    Can you post a sample frame of the video? This will help us let you know if it is salvageable or not and possibly suggest some settings to try if there is enough detail there to expand. – AJ Henderson Sep 28 '14 at 20:02
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The biggest problem you are facing is that a DSLR typically records to the H.264 codec. That codec tries to minimize the file size and the only way to achieve that is to throw out negligible information.
Sadly human eyes are not sensitive to black parts of video, so dark areas are highly compressed. That means you will have a really hard time brightening your footage, since most information is simply lost.

Had you had access to a RAW or lossless recording codec, you might have been able to recover a reasonable amount of your footage, but that would have cost much more storage space and meant more post production work.

If you would like to learn more about codecs, there is an in-depth explanation on Phillip Bloom's Blog.

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You could use the 30 days trial version of Premiere Pro (most editing programs will be able to perform the following options).

The best way to make the video viewable depends on how badly the video is underexposed. If some areas are literally pitchblack, there is nothing you can do about it.

First, try to use the brightness and contrast effect and raise the brightness till you see a difference. Play around with the contrast value as well.

If that does not work, deactivate or delete the brightness and contrast effect and try adjusting the luminance curve. Try raising the curve, so that minimal differences between the shades of gray (lol) will be increased to make them visible. That way, the video won't look really good, but it might be viewable at least.

Try adjusting the luminance curve to something like this: enter image description here

Or maybe:

enter image description here

(Not really sure if the second one would work as intended in this case, but it's worth a shot)

If that still doesn't work, you could try playing around with RGB curves and color corrections. However, if you didn't see any improvement after performing those steps, I don't think you'll be able to perform these steps.

If one of the above steps works, you might be able to even get some color in it using RGB curves and/or increased saturation, but I'm not sure if this will do anything if your material is really that highly underexposed.

  • Premiere is overkill for this. Any tool has basic color correction necessary for expanding the luminence space of the video, however if there is as little detail as he is claiming, it is unlikely to make any difference in the first place as there is nothing at all to expand. – AJ Henderson Sep 28 '14 at 20:01
  • Well yeah, but that's no reason to not give it a shot. Worst case it doesn't work at all and the 20 minutes needed to do this are wasted. I pointed out that most video editing software should do the job. I recommended Premiere because it offers different advanced approaches to color and tone correction which may or may not work better than others and because I know the program and thus was able to give specific directions on how to approach the problem as well as offer screenshots. He asked for a free program or a free trial anyway ... – MoritzLost Sep 28 '14 at 20:09
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    +1 That's fair, I don't mean to detract from your answer, just want to make sure they understand that if there is enough there to extract, they don't have to buy a $600, $240 a year program or $30 a month program to do it. It's also probably worth pointing out that if they want to go super advanced, either Speedgrade, After Effects or Divinci Resolve would all offer even more advanced options (though I understand that you were explaining what you know.) – AJ Henderson Sep 28 '14 at 20:14
  • Fair enough, no hard feelings! I just wanted to explain my answer, though you are of course right saying that there is no need to buy a commercial product! – MoritzLost Sep 28 '14 at 23:25
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You are almost certainly up a creek with no paddle. Since video is less than 8 bit color, what you see when you watch it is what is there.

If there was some small amount of detail but it was just really dark, then you could alter the white point and get something minimally usable out of the darkest part of the image. This can be done with any decent video tool, including most free ones as it is basically just a brightness boost (make everything medium grey) crossed with a contrast boost (make the darker greys black and the lighter greys white.)

If, however, it is almost solid black like you said your video looks, then there is no (or very, very minimal) detail to expand out. There is no "hidden details" like you have in a 12 bit or 14 bit raw image that are hiding outside the visual range of the image. This is also why color correction on video footage is so much more of a challenge. It is also why the ability to shoot RAW video, which does capture 12 or 14 bit images for frames on cameras like the 5D Mark iii is such a big deal in the DSLR video world right now, because such functionality used to only be available on $30k+ cameras.

  • Neat! Does it use some kind of lossy compression when recording? cinema5d.com/shooting-raw-canon-5d-mark-iii-2014-magic-lantern says 25min on a 128GB card. 14bits*3components * 30fps * 60sec/min * 25min * 1920*1080 / 8bits-per-byte / (128*1024^3) = 3.05, so they're getting a compression ratio of only 3. So probably lossless. – Peter Cordes Jan 15 '15 at 11:05
  • Yes, raw video is lossless normally, there are some ways to compress raw in a lossy way but the 5d doesn't have the specialized hardware to deal with that. – AJ Henderson Jan 15 '15 at 14:47
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Like others have said, just load your video in anything and play with the brightness effects. Even a gamma curve could do the trick.

Or save a frame of the video where you can see anything at all, and play with that in a still-image program like imview, and play with the brightness / contrast / gamma to see if there's anything still there worth looking at.

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