Noise Reduction Tools and Techniques in DaVinci Resolve

hello everyone it's david tercera here again and this week i'm going to be speaking to you about noise reduction and now those of you with resolve light who know that you do not have noise reduction built into your program don't worry I'm going to talk about some alternatives you have both in plugins and free things you can do within the program itself but we're also going to examine noise as a overall look of exactly what is noise reduction what's it doing and how it affects your shot and good ways to get around it we'll be looking at both the spatial and temporal internal resolve noise reduction as well as neat video ofx the video we're going to look at all this on is a music video that I did a couple months back for a band called we're the ocean this song is great it's called good for you you should check it out is really great video it's a single one take video which is really impressive shot by a good friend of mine Jake Harris and directed by Edward John Drake now this video was shot on dragon using the highlight olp f at a 1600 a si and this shot using Van Diemen lomé around front and morphix was you're pretty cool little lenses with cook speed pan career elements they ended up shooting wide open and so they had a lot working against them this is a single take one shot music video that's about four minutes long give or take and is a real incredible work in terms of the choreography and the camera moves and the lighting transitions so they had a lot of things working against him while they were making this the video that we're seeing and that went out finally was the final take of this and so as they were shooting throughout the day they tried to hit Magic Hour but each take as time went on got obviously darker and darker and so they ended up having a bit of noise problem by the time they got to the end but it's it's worth it because the final take is such energy and everything hit its mark spur fect lee it's a really great video but at first they were worried that things were too dark and there was too much noise so we had to do a lot of stuff to sort of clean this up and make it usable well we're going to take a look at just one part of this video that I think really does a good job of showing noise and what you can do with it to help eliminate it so this is a shot from the beginning so I've got this very complex node tree right here and this is now what I use to create the video this is a sort of learning node tree I've set up to show you different things about noise so you can better understand it and your different options in terms of eliminating it when we got this shot it came in looking like this now that may look unusable and I'm actually not working off the raw our 3ds here we had to ship this video out very quickly and so the editor in LA had to send me over Knights of the finished product which was d squeezed and compressed down to 1080p via DNxHD 220 megabit and there's still a lot of latitude in the final footage but as you bring that up you reveal a lot of noise that is still in the original our 3ds but it's exacerbated by our workflow fortunately we have lots of tools that are disposable to get rid of that so let's take a look at this so real quick just you know I have this first primary node here which isn't doing anything except bringing the levels and the color up to where we used it for the final video so for all intents and purposes we can ignore this now some people like to denoise before they do any primary Corrections I prefer to denoise after that's partially a workflow thing so you'll notice all denoise solutions tend to be taxing on your GPU and CPU depending on how your system is set up you can do things like node caching and smart caching which we may talk about a later time but but it's easy to get caught up fiddling with noise reduction instead of focusing on getting the grayed out and done quickly so what I tend to do is make sure I've got all my primaries done go through with my secondaries and then as my very last pass I'll go in and denoise the shots I really need it so let's take a look at this the first thing you want to do when you take a look at noise if you're not in a hurry and just slapping something on top of it is understanding what parts of the shot are actually noisy so you can see here when let me blow this up for you so there's really two types of noise there's chroma noise and there's luma noise and luma know is tends to be a sort of even washer noise across your image especially you'll see it a lot more in shadows and highlights but what it is is this sort of an even noise across everything and sometimes can be very pretty for example an Alexa at 1680 is going to be not a tremendously clean image but is going to be have a a pretty grain that feels sort of organic and if you're lucky you can get away without having to denoise it other cameras you can run into something that you have a little bit more chroma noise and so you can see in this space right here we've got this really ugly noise there's a lot of greens there's a lot of reds it's you over here there's just a lot of stuff going on that is not pre at all and even emotion which helps to get rid of noise it's still really ugly stuff but it's not all is not lost so there's still a lot we can do here and so what I've done first to better illustrate exactly what type of noise we have here is I have created splitter combiner node and this is not something you need to do typically when noise reducing but I just want to show you what noise is you have a better understanding and you can do that right here with the splitter combiner node alt Y on Windows command Y on Mac and what this does is it splits damage up into red green and blue Channel and so let's take a look at this right now so what I've done is shown only this red channel here and you can see just how noisy the red channel is it's faced back here there's a lot of noise going on right here if I switch over to the green Channel however you'll see this is a lot cleaner image and this is pretty typical for digital cameras pretty much across the board but especially in cameras like they have 65 they have a lot bigger and more present green photo sites because green is most important when encoding that digital data so they tend to focus on making sure the green channel is as clean as possible and that really reflects right here you can see there is still noise present especially considering how dark this image was when we started but it's a lot cleaner than that red channel right here which is just a mess going over the blue channel we can see it's somewhere between it's definitely not as noisy as a red but it is still much noisier than that clean green Channel and so that gives you a good idea and this is actually a technique you can use later so if you have a camera that for whatever reason has a bad red photosites is really noisy you can actually do a splitter node like this and apply your noise reductions solely to the red channel which will make a big difference in cleaning up just the problem areas with noise while the rest of your image detailed the big thing about noise reduction is you want to do as little as possible because it has the tendency to sort of smooth out your image to lose a lot of the highlight details and luma details which make your sort of entire image look soft and washed out and in a worst-case scenario skin gets sort of plasticky and the whole thing feels this really digital and there are things you can do to get rid of that even if you don't have an option there especially things like adding grain and different types of sharpening which we'll cover in another video at a later time but one of the great techniques for getting around that is focusing on just denoising the parts that need to be whether that's certain luma areas or certain color channels so for example if I were just adding noise this red channel there would still be noise as we can see in the blue channel but a lot of the noise wouldn't be nearly as bad as what we're seeing with everything all combined similarly I've created a layer node here with the luma and the chroma and these are recombined using just the composite mode ad and luma channel this node has all the saturation produce and the chroma channel has all the getting taken out and again we can take a look and see the noise isn't terrible in the luma you can see there is noise here and this is what I'm talking about with luma knows where it's definitely present but it's not sort of like just on his skin where we would see like with that red noise or um any particular areas sort of an even washing this noise itself isn't that ugly it's it's not desirable exactly the way it is the dragon doesn't have particularly pretty noise like you'd find in some more filmic cameras but it's still a great image and this noise by itself I would probably argue especially on a tight deadline that is present and we can move on and not worry about it and let's take a look at the chroma noise now you'll see that this is because it's such a dark image we've done much to work with so let me turn up the gamma so we can see a little bit better and you can see again especially in his face there's tons of chroma noise here back here there's a lot of blue noise writing here a little bit of green in his shirt you can very quickly see you know especially in these shadows that most of the noise problems we're going to be working with here are in the chroma noise so let me go ahead and reset that get out of here and go back to our full view and now we can focus on the actual noise reduction so again these notes right here aren't actually for doing any stuff I've just got them here to illustrate exactly what kind of noise reduction problems we're dealing with and so give you a better understanding of what noise reduction is doing now resolve has two noise reduction built in and this is only on the the full license version of resolve so those of you with Blackmagic cameras or those of you who have purchased the resolve software you have access to this those of you using the free resolve light which I guess actually the names have changed now with the resolve 12 so you have result 12 has the free version and resolve 12 studio as the pay version but regardless these are the two noise options you can get to them right here under this little star and so we have spatial noise reduction and temporal noise reduction and they work in two different ways and you can use them by themselves together or whatever combination you find works best and we'll go over some some options with with noise reduction that you can do in the future to sort of make things even better similar to how we've done our splitter nodes up here but first let's just take a look at this spatial know that I've got already up here so turn this on quickly we've got a couple of options here your radius your blend and your luma and chroma which you can gain or on gang and I've got them on ganged right now but let me go ahead and just reset everything so this is what we're looking at right out of the box there's there's nothing on and we've got lots of noise so let me just without doing anything just turn this up a little bit and you can quickly see the noise on our image is disappearing the noise is still there I mean you can see colors and stuff here it's maybe a little bit blocky but it's a lot less than it was before and we can turn it up even more and you can see all the noise is gone but we've replaced it with this ugly sort of blocking effect so what the spatial noise reduction is doing is searching for areas of similar color and luma values and sort of blurring them together and so what that does is it gets rid of all the individual noise specs but we lose out on some stuff at the same time we lose in particular head sharpness and we give these artifacts where the noise reduction is thinking like for example on his nose here these are two distinct areas and in an effort to preserve the edge detail it's sort of created this harsh mask here and that's what's causing this blocking and so this is not a very pretty noise reduction it works in a pinch but this is not necessarily what we want to use but let's talk about these options here and see how we can make this a little better so the radius changes the search area that the algorithm uses in order to create different amounts of noise reduction so let's mess up the large here and zoom this back in you can see a lot of the blocking is is significantly improved you can see there's almost a little bit of blending going on here there's not that harsh edge and while it's not perfect it is significantly improved over the small radius now this comes out a little bit of an expense the small search area allows your computer to run much faster because for every frame it's not having a search tons and tons of pixels just to make one pixel look correct the larger you create your radius the more time your CPU or your GPU has to spend searching through all these in order to optimize what areas get smoothes and what areas get left alone and you'll find this in all noise reduction there's a delicate balance between quality and render speed and it helps to have the fastest GPU you can and making sure even a VRAM to deal with larger scenes especially when we get to the temporal noise reduction and we'll talk about that in a moment going back and thinking about you know how we saw more noise here in the red channels than we did in the luma channels we can also optimize which areas get more details affected for example if we were to just denoise in the luma channel limiter my chrome annoys off you can see we've got lots of blurring and so we've lost a lot of detail that the luma channel holds and we still retain a lot of this noise and if we do the opposite you can see we've got this very even luma nose which almost looks filmic and taken away a lot of that ugly blocking color noise so this is a lot better start already so zooming in we can even see that some of that strange blocking isn't happening here because a lot of that is affected from the the luma nose noise reduction because most of the detail in your image resides within the luma channel and so you want to be very careful when increasing this luma threshold to do as little bit as possible a deaf touch here is definitely preferred so I've turned the luma up a little bit and we started getting some blocking but you can see this is a not a bad start we threw some film grain on here this would be a pretty good image and I'd be pretty happy with that now we've got this blend tool too which is for example if you don't want to have to go back and read grain things you can start increasing this and it blends this image with the original image so you get some of the original noise back like you can see back here and over here but it helps to reduce on the blockiness that is big problem if you don't go back and read grain things so that spatial noise reduction is the fastest noise reduction you have but it's also the least precise and can easily result in those blockings in those plastic looking skin okay so let's take a look at temporal noise reduction over here and now the way temporal noise reduction works is it compares frames next to the frames so let's say this is our frame that uh we happen to be noise-reducing at this time and so we'll look at a couple frames before so you can see look at the noise right here in this car as I click back you can see the noise moves pretty dramatically and as I go shot-to-shot you can see the noise actually moves and the what temporal noise reduction does is it says if I average enough of these frames then the noise on this should move frame to frame and it shouldn't be the same in any single frame and by averaging these and combining them we can figure out what this image was before all this noise was here and it's a very clever trick and it works exceptionally well in terms of getting rid of just noise while preserving or luma details so things like it shirt here his eyes so things like his shirt here or the specularity in his eyes so let's take a look at this let's turn it on and when you mess with temporal noise reduction you've got an option again quite similar to the radius here where zero frames is off one frame will search the frame before and the frame after whatever frame you're currently on and two frames will do two frames to four and two frames after two frames to four and two frames after gives you much larger search area and we have especially bad noise like we have right here should result in a lot cleaner noise reduction so let's take a look we've got the thresholds turned up extremely high right now with the full motion radius so this is this is dimpled motion of shown as high as it goes so let's take a look here I can zoom them pretty far this is with it off and this is with it on and you'll notice wow his face isn't really changing that much and that's that's a big problem and I'll point out why in just a moment but let's take a look back here instead you can see here the temporal noise reduction is making a huge difference especially these backs and these shadows took over in these trees right here you can see off on off on there's a big difference in terms of that but it's not affecting his face as much as we'd like and here it is on and that's still pretty unacceptable amount of noise and if we go look at our settings you'll see I've already got the noise reduction turned up just about as high as it'll go you know motion radius large motion estimation the faster better it shouldn't matter much on a mostly static shot like this ah so what's up what's going on here why does this this better noise-reduction not looking better and so turning off this noise reduction for a moment let's take a look at how this chroma noise moves on his face and you'll see this noise is actually fairly static so shot-to-shot there's still a lot of color going on in here and and this is because this sensor was pushed so far out of necessity in order to get this shot again remember how far how dark it was as he walks into the light it's a pretty great shot and again I highly recommend you check out this video but when we had to push it up we've revealed a lot of the the noise that's just present in this sensor things like black balancing can help mitigate this some but what this is doing is it's leaving this mostly static chroma noise shot-to-shot that's especially exacerbated in his face which has lots of red we boosted the saturation quite a bit in order to to get that color back from the shadows resulting in this really bad chroma noise look and so what we want to do in this scenario is let me turn this temporal noise reduction back on you can see it's especially affecting his hair here from the motion estimation but let's go back to here and let's turn on this spatial analyst reduction but let's go back to it and turn the luma completely off and so what we've got here now is this spatial noise reduction reducing all this gross chroma noise but spatial noise reduction is really bad with luma noise and it does a really bad job about making things blocky so I've turned off the luma completely and I will go back to our temporal noise here and I'll blow this up and I'll turn it off and on you can see it's taken care of the Loom annoys back here and so we've sort of merged these two to have this pretty decent compromise where spatial is taking care of our gross chroma noise and the temporal is taking care of our luma without affecting the luma details keeping our image still looking sharp and so that's a great combination and that's really how you should be using these in difficult scenarios it's combining both these tools in order to get one great one let's turn them off for a second and talk about third-party solutions now everybody knows need video is familiar with it now mute video sells a ofx plugin which runs within resolve it's a little bit more expensive than the regular version but it's like $200 or something ridiculous which is such a great value for the noise processing it offers it's better than just about any solution on the market outside of a couple high-end things that aren't available here like a dark energy or some of the proprietary things Nakota makes but let's take a look and turn this on and you'll see a little bit of what I'm talking about in terms of the plastic miss that this does and this is utilizing both temporal and spatial noise reduction but it's doing a much more aggressive job of it it's left a lot of details here so you can see his hair still looks pretty good let me turn it off it's not affecting it as much as the temporal noise reduction is you can still see some of the details and his beard some of the stuff in his jacket and shirt but his skin is sort of gone fake looking it's lost the pores in the detail which might never have been there but you know it's definitely an issue and so this is where you run into the issue would need video but we'll talk about that in a minute let me let me open this up we'll take a look at like what exactly we're doing so here's what new video we're just working with this is the this is neat video for the latest version and that's a quick aside most people don't realize that they can do this but you can go to tools your preferences performance and optimize your need video settings a lot of by default I think it only runs on CPU and will run real slow if you go here it off to my settings you can whatever and hit start and it'll run through all the options of different combinations of your GPU combinations with your CPU to figure out what's asked is for you how many cores is to devote you know like if I use both my GPUs I can get 17 frames per second and this is a great way to speed this up because again noise reduction is processing intensive and anything can do to make it go faster definitely appreciate it so let's take a look again at this and you can see a lot of this information that I was showing you earlier here with these split nodes is available here you can see how much high low medium detail noise there is you can see where each channel is noisy the Greens apparently noisy down here in the shadows and the Reds noise you're up on the top and now using me video is very simple what you do is you just draw a box in an area that you want to analyze the noise now you can't just draw this box anywhere unfortunately you have to be very careful where you do it if you want to focus on something that's very static in terms of its chroma and its luma and this lets you make sure you're only analyzing noise and not different changes in terms of color or how bright something is you also want to focus on getting something that has as little detail as possible if I were for example to focus on this area here which has a a fairly even color and luma value but it has filled with skin detail which will lose if I if I run this so looking at this image you can see over here on this junk that this area is pretty even it's out of focus there's not a whole lot of detail here and so I can select this just at Auto profile run the fine tune on it and zoom out and hit apply and for the vast majority of things you'll notice that this is all you need to do let me turn it off this open FX open this up and zoom out that is a great out-of-the-box noise reduction that took almost no time we didn't have to fiddle with anything they're still detailed as beard in his hair his skin doesn't look great but it's not horrible and we can fix this easily with some grain which I've got enabled over here this is actually using the film convert engine which has some really horrible looking lots in it but is a great great Grange in Iran you're not in an Asus project so you turn that on and similarly let this nice even film looking grain without ugly chroma blotching and we've come a really long way since our original shot and so going back and turn that off real quick we'll go talk about this again now if you want to do for example use just temporal or just spatial noise reduction you can disable them or enable them here in the noise filter settings tab and you can also do other things like news dust and scratches or get rid of some of the artifact removal that sometimes occurs with post sharpening and you can even add smoothing and sharpening here as well as the same mixing tabs that we see down here and you can adjust the the quality temporal you can actually do just ridiculous amounts of temporal reduction for this project for the sake of rendering I've got it down to one but it's a tremendously powerful plugin and something I really recommend one thing to note with it though is that if you're working on high resolution projects for K 5 K 6 k footage especially footage said that needs to be debated so you know you're dragging your epoch and you're working on a 4k or greater timeline need video and temporal noise reduction in general uses a lot of VRAM so for every single frame the renderer is trying to create it needs to render approximately if you're on just a single radius so 3 or if you're on 2 or 5 you know up to 11 or or 5 frames just for a single shot and so it quickly adds up in your vram and so if you have a car that I've seen cards choke at 3 gig B RAM 4gb RAM which is why I've actually got a Titan in here specifically for this so that the 12 gigs guarantees I don't run out but I've seen meet video choke especially need video for on 4 gig cards just one thing to be aware of you should be fine with 60s on most projects it is something to consider and sometimes disabling temporal noise reduction and relying on just spatial is all you can do because of that vram issue I can't recommend you video enough this works in both the regular version resolve as well as the license pay for version it's easily worth the $200 or so that it costs and the devs are really responsive I don't have anything but nice things to say about the neat video team just be careful not to overdo it and ensure that if you're using this and you want to avoid plastic looking human skins you need to add grain back over on top of your project in order to get the detail back but we'll talk more about grain in an upcoming video because that's a whole topic that can use plenty of time on its own now I just want to go over this one more time and take a look at this other thing I've set up just to illustrate a couple more concepts that we've already discussed so here I've got the same primary that we've already done before I and then I've got this splitter node again so this is red green blue and then this qualifier right here and currently none of these are doing anything but I wanted to show you a couple of options here so um let's say we wanted to just get rid of certain parts of the noise in this image like we know this red noise here is terrible and this blue noise down here is terrible so what we can do is go down here in effect just this spatial noise reduction for just this section um now you might be tempted to say oh I want to get rid of all this red noise here let me just jack up the chroma and you'll see oh no nothing's happening and that's because what we're dealing with here is just a single red Channel which actually has no chrome associated with it it's just been stripped down to be just a little component of that channel that's recombined so chroma doesn't do anything because there is no chroma but if we jack up the luma you can see we've got this very noise 'less almost pixelated this looks like one of those cheap photoshop plugins but it but the noise is gone I'm in the red channel and if we go over the blue channel we do the same thing here and turn this up and we've got another like solarized cheap looking thing but if we turn it off we can see we've got a pretty decent approximation between we and so there's still green noise especially down here in this shirt but it's nothing bad we can go back and say we want to take out just a little bit of that green noise we can turn it up just a touch here and while we are impacting our sharpness at this point this is a way to handle like oh we need a lot more red reduction or we need you know not as much blue and then are hardly any green so you can get really fine tuning into here in order to preserve as much limited details possible without having to go into temporal noise reduction so that's a great trick in terms of analyzing just certain parts of the image similar here we've got this qualifier and say we only want to affect you know the shadows so we've got real bad shadow noise we can go in and go to our qualifier here and we can lower you know this down the luminance down so that we're only affecting the shadows here and even this out so something like that we can clean this up so it's not so messy you can add a little blur to it and now we can clean up just the shadows and so you can see back here pull this up that this area is cleaned up but our our highlights are still great this isn't a good solution for this particular image but if you have a camera that shoots lots of shadow noise but the highlights look beautiful then this is a great technique in order to only affect the par statements that really need noise reduction again noise reduction keys to do it to only the parts need it and do it as little as possible so you're not impacting your sharpness and forcing yourself on necessary render time similarly you can apply the same effect to just specific colors like if I want to just do this face here and this is in probably the best way to do this I think you'd be better served probably working within the details here that the channel splitter but it'll work in a pinch and just to do something rough and we can clean up just a face here and leave all this other noise so that's a great technique in terms of getting to the parts attainments that are necessary in order to clean up as best as you can now for those of you without the full version of resolve which enable these spatial noise reduction and temporal noise reduction and you can't or don't want to purchase meet video there's a little bit of a trick we can do to get some noise reduction when we're in dire straits here and I'm going to show you that real quick and so this trick depends on the fact that most of the sharpness of detail in in video is contained within the luma channel and the individual components of the color channel can be messed with without affecting the sharpness of the overall image too much and so again I've got this splitter combiner node here I've got this extra no that's not do anything if you want to do this again it's right here it's add splitter combiner node alt Y command Y on Mac I believe and it splits your image up into red green and blue and combines it back again right here and so you can go here and we can double up or we can look and see you know here's our bad noise in the red Channel here's our minimal noise and the green Channel and here's our meeting noise on the blue Channel okay so what we're going to do is we want to go to our splitter channels here and go up to the red and want to make it so we can see just what we're doing here and I'm going to just click over to the blur panel and just blur the hell out of the red Channel and I'm going to go down the green channel one or the blue Channel and blur the hell out of that let's see what we've done well so here we are we've got this I mean not great looking but not noisy image here we can compare it to what we had originally and it's not nearly as sharp as our original image but you know it's the details there but it's usable maybe looks a little bit glowy but this is a great trick in order to get rid of noise if you don't have a noise reduction plug-in and you desperately need to now you'll see we've got this green fringing everywhere this is a part of the problem of a pushing this stuff so we can you know sort of mess with these values here to try and push back some of that green fringing so I've sort of shifted stuff up and down that sort of slides her noise side-to-side uh and you can play around with things to try and get around this or let's let's say maybe we wanted to you know switch just do note sizing here and and zoom zoom in a little bit on the green channel just just the tiniest little bit God now we got all those chromatic aberration oh maybe it will shift this up a little bit no that doesn't do it what about zooming zooming out there so that's that's better than it was you can see here again how we've reduced this noise and uh again this is not definitely not the preferred way to do it we've got this fringing on the side we probably punch it on the whole thing now but if you are in a pinch and you do not have any noise reduction plugins by splitting all this stuff into separate channels it's a great way to get around that alternatively your let me go ahead and reset this let me grab my primary connection correction from over here so get this go back over here and this down here load up my primary we can also do a similar thing with a layer node arm changes to add lower the saturation on our top lower the gain on our bottom so this should be more or less the same image we were seeing before we'll double check yep it's the same and doing the same exact thing down here in our chroma channel and we can see again I'll and I'll temporarily turn this up so we can see what we're doing but just blur that and let me turn this back down turn this off and zoom in and you know we've got here's here's what it was here's what it is now so it's a pretty passable in term noise correction in terms of getting rid of that chroma noise and leaving just the lemon oiz while still preserving our details because again the detail is carried here you can see this is where you know the shirt of the hair and stuff and this right here is just color instructions so by just blurring part of the image we can get a sort of selective noise reduction and again this is where we were this is where we are now and I don't know how much YouTube compression is going to make this look like garbage but it is a big difference and we've got some sort of D saturated fringing along the top and the edges but this is a great way to get noise reduction in a pinch when you don't have any other tools and that about does it in terms of noise reduction we've covered what noise is where we can see different types luma and chroma and then different types of noise reduction both spatial-temporal third-party plugins like neat video and also different ways to apply noise reduction to only the parts of the image that need it I hope you found this helpful and I'll have some new tutorials coming out soon about things like grain and other things to help you make your noise reduction process a little bit easier this is David rusev Egan and thanks for watching

Channel: David Torcivia

Views: 108,415

Keywords: DaVinci Resolve, davinci, resolve, Blackmagic Design (Business Operation), Color Grading (Film Job), color grading, color correction, tutorial, Filmmaking (Industry), Noise Reduction (Field Of Study), noise reduction, neat video, neat video ofx, ofx, temporal noise reduction, spatial noise reduction, post production

Id: Nf9z_BJ05KY

Length: 36min 15sec (2175 seconds)

Published: Tue Sep 15 2015