I have a master avi of a concert video filmed back in 1992. It's kind of an important show, so I want to restore this and get the best out of this video that I can. I'd like to clean up the noise for one thing. Another thing is that for the majority of video it's quite dark, so I'd like to brighten it up so that I can see the performers a bit better. Here's my explanation of the clips I've attached.
Clip 1 - As you can see in the clip labeled clip 1, the brightness is fine here (stays like this for the first 10-12 minutes of the concert) - I'd like to maybe raise it a tad, but very little. The noise however, like the whole video needs to be cleaned up.
Clip 2 - The lights go off about 10 minutes or so into the show, so I'd like to brighten this up as best I can to see the performers as best as possible. And again, I'd like to clean up the noise - the whole video needs the noise cleaned up as that is a constant throughout.
Clip 3 - Just another little clip to show how dark the show is once the lights are turned way down at the club here.
A forum member on here suggested to me that I use VirtualDub, since I am a beginner. I downloaded it last night along with a Filter pack consisting of about 200 different filters. There's so many, since many people put out their own filters.... does anyone know the best ones for de-noise, and the best one for brightness? Again, I'm looking to get the best I can get out of this video, and from my eyes - the main problem is the noise and of course the darkness. I would appreciate any tips on what to concentrate on, also what filters may be the better ones to go with on VirtualDub. Thanks a lot.
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I took a look at clip 2.
There is 'low-light filming' and there is 'no-light filming'. This, in my opinion, falls in to the second category.
There really is no detail in the video. Adjust brightness or contrast just magnifies the low-light noise and try to remove that will soften what is non-existant in the first place.
This is just my opinion and others may have other ideas.
Why did they cut the lights ? Could anyone present actually see anything ? Or did the camera just try to record in available light which was simply not there ?
I know the footage itself is not the greatest, and I'm not looking for a miracle or any sort of perfection with this. All I really want to do is raise the levels of bright/contrast a bit so that is a little easier to actually see the performers. Like I said, I played it in Windows Media Player, it was totally dark, I went to enhancements>video settings then raised contrast a bit and bright and I could see the performers at that point. Only thing that needed to be done was a little noise reduction. So that's really all I want to do - raise the levels of bright/contrast to actually be able to see the performers and remove a little of the noise... I know I probably can't get all the noise out due to losing lots of quality, but even a bit to make it more watchable and I'd be happy.... If anyone has any input on how to achieve this, I'd love to hear it! Thanks. I'm using Vdub, so any input on the best of the best as far as these sort of filters, I'd love any info that comes my way. Thanks!
I would stay away from HDRAGC on footage like this, especially if you don't know avisynth.
Try playing with the level filter in vdub, you will bring up the noise but it will be "watchable." This video will never look great no matter how much denoising you try to pile on later. Using the level filter be careful to keep the blacks black and don't blow out the highlights. Quick sample:
smrpix, thanks so much for the information! See, I'm such a beginner at this stage that I didn't know about the "levels" filter and that I could do that with it. I guess I could do the same with the rest of the video (the majority of it is really dark) like you see in clip 2 and clip 3. I guess I can play with the level filter to make it so that I can at least see the performers, thus making this watchable. If you don't mind providing another little example of one of the darker clips (clip 2 or 3), that would be great, but not needed - as I can always fiddle with the levels myself. I was just psyched to see this little example you gave on what can be achieved by this filter.... Yes, this is exactly what I want to do (just make things more visible and not hidden by darkness), especially during the parts where the lights go out. Would you recommend any de-noise filter to be applied after adjusting the levels to my liking?
If you're going to restore old video, you can't live without Avisynth and VirtualDub. VDub is easier and more intuitive, and it can work wonders, but Avisynth is the tool for utterly crappy video like these samples.
Clips 2 & 3 are in serious trouble (all of them are). Clip3's noise level is "louder" than the video signal itself. You can't just make it "brighter" (you'll make the noise brighter, too, and the noise itself will be brighter than most of the signal information!). Some of that noise looks like grain. That's not what it is. Grain isn't a problem for Avisynth. The two biggest problems here are that effectively you don't have a signal; you just have noise, in the form of crushed darks and low-light artifacts from both the camera and the recording. If you have more nosie than you have video, removing the noise does not reveal the video -- it removes the video as well, since the noise is the major component of what you're seeing.
(Below) frame 180 of clip3, unprocessed. This isn't just grain. It's your camera's encoder failing the "no-light capabilities test", resulting in artifacts and severe crushing. Crushed data isn't just "dark". Crushed data is destroyed data. It's gone. Nada. Zilch. Below the noise, nothing's there. There is no way to get the original scene's data back, because most of it was never recorded.
(Below) Among the tools you'll find useful (that means "essential") in video work are various histograms, vectorscopes, and other graphics goodies. Adobe Premiere Pro and Vegas Pro charge big $$$$ for theirs. Avisynth's and VirtualDub's are free. The image on the left is a YUV histogram, to look at the way video data is stored in your source. The image on the right is an RGB histogram, for seeing how the video will display in various monitors and TV's. The YUV levels histoghram shows luma (brightness) at the top, the blue-green channel in the middle, and red-green at the bottom. In RGB , you see all three channels Red-Green-Blue, with a composite of the brightness or luma at the top. The RGB left side is dark values, the right side is bright values.
These histograms show that Clip3 has severely crushed darks. In the RGB histogram of frame 180, all of the color and luma sits smacked against the left-hand side -- which means that essentially the only colors you have to work with are blacks. The YUV histogram shows color content as a thin white line in the middle of the graph: if you were looking at a dead-black frame, that's what black would look like in YUV. Both histograms show that the luma and chroma range is packed within the narrow range of RGB 0 (and below 0) to RGB 45 or so. RGB 45 would represent the darkest shadows in skin tones. Skin tones usually range from dark RGB 40 shadows to RGB 180 highlights. There is no color value brighter than than RGB 45. There are a few specular highlights at around RGB 240 or so, but above RGB 40 there is little or nothing to nothing to work with.
(Below) You can brighten this grimy stuff -- and the noise with it. In frame 180 below, the video hasn't just been "brightened", it's been low-contrast enhanced to bring up darks more than it brings up the brightest areas. A typical "brightness" control just moves stuff around on a histogram, but contrast masks and YUV level controls can work specifically on the darks and expand them to a more useable range -- much more powerful than a brightness button. Frame 180 has been brightened to far beyond the original range. The original RGB-0 black borders are the darkest part of the image below, and they'[re at RGB 44 -- which is gray, not black. You can see that making the darks brighter does not reveal more detail. All you can do with crushed blacks is make them brighter (gray). You'll also note that expanding the darkest colors resulted in a nearly monochrome image. You can't make crushed colors into variegated colors. They will always be one color, no detail.
(Below) Histograms showing how much the darks have been expanded -- far beyond the area where blacks should reside for TV, which is around RGB16 at the left-hand line on the RGB histogram. Note that all three RGB colors have about the same shape and position -=- that's what dark grays look like on an RGB histogram.
(Below) a 2X enlargement of the brightened frame 180. The squiggly junk and mottling you see isn't grain. They are artifacts. You can see that the junk is part of the image itself, and a lot of it is brighter than the "video". This stuff moves around a lot, but it isn't going anywhere. You can use strong smoothers to clear up some of it -- and you will destroy whatever detail is around it. The result will be a badly blurred image with faces that are nearly unrecognizable.
Last edited by sanlyn; 23rd Jan 2013 at 13:52.Our inventions are wont to be pretty toys, which distract our attention from serious things. They are but improved means to an unimproved end. -- Henry David Thoreau
(Below) After a few hours and a bunch of filters I managed to eke a little more "detail" out of Clip3. Got rid of all the grain, but I elected to do only a small amount of smoothing on the artifacts -- otherwise the lesser details would dissappear into a foggy blur and the girl would look like a lump of clay. In the image of gframe 180 you can clearly see the artifacts that results from no-light and crushing. But no "grain". I did get lazy at one point and used AutoLevels (other AGC controls did a terrible job and only mare things worse), then had to correct for its missteps -- I hate auto gain controls, they never do what you want but they can save some time. So the attached video below does show some "pumping" in a few frames from that bright window in the background. The nosie level is so high I had to use a higher bitrate to get a cleaner video; high noise levels always demand higher bitrates. This made the video about 5 MB bigger than it should have been.
Because of the way our forum's image viewer works, most posted images look darker than they really are.Our inventions are wont to be pretty toys, which distract our attention from serious things. They are but improved means to an unimproved end. -- Henry David Thoreau
Wow! Well you have done much better than anything I have been able to achieve so far. I'd be happy with this quality throughout. The part where the lights are on at the show is only about the 1st 10 minutes or so of the video... the last hour or so is the darkness.... Can I ask you how exactly you achieved these final results? Because at this point it looks to be about the best that I'm going to get out of this - and this is a vast improvement over the original. Do you have the settings you used on hand/how I can plug all this in at home tonight to complete this project?
This looks much more rich! How did you get it to look that much better? You did this with avisync? I'm a beginner and just started fiddling around with virtualdub. I have never used avisync.... I assume that you did this to the clip I have labeled "clip 1," correct? I can't imagine getting these results from the super dark clips 2 and 3. Also, did you de-noise this? Looks great... You used neat to de-noise?
Our inventions are wont to be pretty toys, which distract our attention from serious things. They are but improved means to an unimproved end. -- Henry David Thoreau
Avisynth steps and one in VirtualDub. Used one filter you'd have to buy (NeatVideo), and encoded with h264. Just "plugging it in" would be a weekend project.
I dunno, I think it could be cleaner, and easier, and I'd do away with any autogain nonsense even if it does save time. It's still mighty grungy, IMO. That video is one where you'd take a piece like Clip3 or 2 and try 3 or 4 different things, then use the same methods for the whole video. The industrial strength plugins you have to run with stuff like this runs veeerrry sloooowwwly. No way to avoid that.
FYI, the Avisynth filters I used (mostly at defaults. Mostly) were:
ContrastMask, SmoothAdjust, MCTemporalDenoise, TemporalDeGrain, RemoveGrain, DeBlock_QED, GradFun2DBmod. Just looking those up would take forever if you don't already have them, and they require a collection of support plugins.
With VirtualDub: AutoLevels 2002, NeatVideo, gradation curves, ColorMill
Will try something else later. It oughtta be easier than the above, but I ran out of time.