32 Replies Latest reply on Dec 10, 2016 9:18 AM by chrisw44157881

    Waveform monitor still shows illegal levels after using video limiter

    CLVPRO

      I was wondering why the YC Waveform monitor someimes still shows illegal levels (past 100 IRE) even when a video limiter effect is used on the clip.

       

      It exceeds both with a single clip on the timeline with the effects, and also when I nest several stacked layers and apply the limiter to the nested sequence. Does anyone know a way for the video to actually limit at the levels needed for boradcast?

       

      Sometimes the levels look ok before I render the whole work area, but afte a render the levels extend past the limited value.

       

      Here are my setting on the video limiter effect, which I put last effect on the clip effect order:

       

      Video Limiter

      Reduction Axis: Chroma and Luma

      Luma Min: 0

      Luma Max: 100

      Chroma Min: 0

      Chroma Max: 120

      Reduction Method: Compress All

       

      I am working in Sony XDCAM EX 1080i HQ 29.97 and have checked Maximum Bit Depth for the sequence.

       

      Mecury Engine is enbled on my machine.

        • 2. Re: Waveform monitor still shows illegal levels after using video limiter
          CLVPRO Level 1

          When I first apply the effect, they levels compress in the waveform. Then when I "render entrire work area" the levels expand back, sometimes even more spreadout than before.

           

          I shuold probably also mention that I have applied another effect above the limiter, RGB Curves. Sometimes I also add Luma Curve, and/or Three-way Color Corrector (for secondary corrections). Those effects are applied to grade the images, and get it looking nice and the levels close if not exactly broadcast legal. The limiter is almost a fail safe, or at least that is what I'm trying to do. It seems that whatever combination I try, there still seems to be spikes shown on the waveform after rendering.

           

          I never recall having this problem doing the same process with DV footage for years.

           

          Seems like there might be something wrong with how Premiere Pro is rendering the limiter and/ or color effects with CS5 and/or with Sony XDCAM.

           

          Does anyone have any idea of why the limiting isn't working or what I should try?

          • 3. Re: Waveform monitor still shows illegal levels after using video limiter
            Stephen_Spider Level 3

            I use 3-way CC and Video Limiter all the time without issue. I wouldn't be suprized if some combination whacked things out, but it shouldn't be a show stopper.

             

            I don't use RGB curves, so I'm no help there.

             

            Try setting chroma & video limit to the same value. Just looking at it now, it makes a difference in the waveform.

             

            You can try nesting the clip before adding the limiter.

             

            You might try turning off MPE hardware acceleration before rendering, see what that does.

            • 4. Re: Waveform monitor still shows illegal levels after using video limiter
              CLVPRO Level 1

              Even if I only apply a single effect to correct the levels, and they peak at 100 according to the waveform, after I render they exceed past 100, and also the black level expands. So the problem isn't due to combining effects or concatenation.

               

              It must be a bug with the SonyXDCAM format and rendering.

              • 5. Re: Waveform monitor still shows illegal levels after using video limiter
                CLVPRO Level 1

                I mentioned in the original post that I tried nesting and applying the limiter to no avail. I also tried deleting previews and turning off MPE, and re-rendering and the same problem occurs.

                • 6. Re: Waveform monitor still shows illegal levels after using video limiter
                  LFedit Level 1

                  Hi CLVPRO,

                   

                  I remember having this issue a year ago or so when I was verifying chroma levels from an FCP export, and importing into Premiere. After getting the results you are currently, I tried sending an XML of the same project from FCP to Premiere, and used the video limiter to limit my levels.  After rendering out the sequence and bringing it back into Premiere, my levels exceeded what  had been previously limited.  After hours of troubleshooting I brought in a few broadcast spots that had already been aired, and found the same to be true. The spots weren't rejected, and I've learned to trust the sequence levels with effects applied and not the rendered file.  I'd suggest bringing in some older material to verify, but after I loaded 10 spots or so that were all broadcast approved and aired, I came to that conclusion. Please let me know if this is the case with you as well, as we can all submit bug reports.

                   

                  This is just my experience and take no responsibility for rejected spots following this advice.

                   

                  I have not personally tried this, but try taking the final file you rendered out of Premiere, import and export out of Apple Color with a 100IRE ceiling and see if that file exceeds levels in Premiere.  Then we'd really know if Premiere is reading the levels incorrectly.

                   

                  cheers

                  • 7. Re: Waveform monitor still shows illegal levels after using video limiter
                    CLVPRO Level 1

                    Sorry can't do that test because I'm running PC's here and do not have Apple Color. The previous test sounded like a good way to see how the scopes are behaving when dealing with footage with proper levels.

                     

                    I haven't sent any episodes shot with the Sony XDCAM EX footage to a duplication house with hardware scopes yet. A couple years ago I sent thirteen episodes shot with DVCAM for broadcast distribution. Those clips had the limiter effect on them in Premiere. My notes from them about one show say that the entire signal was 6 to 8 IRE too hot. Also there was a RGB gamut error at some point. Also they said the pedestal needed to be raised. These notes were just from one show, that was shot outside in the winter with snow by a different cinematographer. I DP'd the rest of the season forward, and probably shot with better levels right out of the can that needed less color correction. My point is, at least with this one episode using DVCAM, and probably CS3 at the time, the master deliverables levels were beyond the limiters settings as well.

                     

                    Seems to be that the Premiere Pro limiter isn't properly processing the entire clip, and further more, at least with XDCAM EX, parts of the signal expand (using any of the color correction effects) after render. Before maybe we couldn't see these illegal values in the trace, but now with CS5 they are visible after render.

                     

                    I'll just apply the limiter anyway and color grade using the scopes before rendering. The duplication house will have to run them through a real limiter, and sequentially clip some highlights in a poor manner. Seems like the best we can do for now with PP.

                    • 8. Re: Waveform monitor still shows illegal levels after using video limiter
                      LFedit Level 1

                      I've never worked with XDCAM EX, but thought I'd share my experience if it was of some use to you. Could possibly send a test to the dup house with what you believe to be correct coming from Premiere and adjust accordingly if they have any notes?  Any information regarding your distribution to a dup house in the future will be beneficial to all of use who rely on software scopes.   Best of luck to you.  

                      • 9. Re: Waveform monitor still shows illegal levels after using video limiter
                        Jon Chappell Level 3

                        I haven't done detailed testing with Premiere but I've seen a similar issue with FCP. You add a broadcast safe filter, make sure everything is legal with the scopes and yet the pixels are still slightly out. It's very small numbers - generally less than 1.5% of the total pixels and they're only slightly out, e.g. 14 or 15 instead of 16 for 8-bit media.

                         

                        My theory is that the application only samples a selection of pixels in order for the scopes to operate in realtime and so it misses out on minor fluctuations that exceed the limits. Either that or it's programmed deliberately to give a small amount of leeway.

                        • 10. Re: Waveform monitor still shows illegal levels after using video limiter
                          Kevin-Monahan Adobe Employee

                          One thing that has not been mentioned is the render order of the Video Limiter. Make sure the effect is placed last (at the bottom) in the "stack" of effects in the Effects controls tab. If not, it will have no effect.

                          • 11. Re: Waveform monitor still shows illegal levels after using video limiter
                            Powered by Design Level 4

                            Maybe if an effect must be last in CS6 they ( Adobe ) could make it so that no other effects can go below it. 

                             

                             

                             

                            Thanks for that info Kevin.

                             

                             

                            GLenn

                            • 12. Re: Waveform monitor still shows illegal levels after using video limiter
                              Jim Curtis Level 3

                              Sorry to see you still haven't worked this out.  I have a suggestion for a test and workaround.  You may not like it, but it might work.

                               

                              Export your edited sequence in an uncompressed AVI.  Bring that back into Pr, apply Curves or the Limiter (if you must), and export again, but not to XDCam.  Choose another codec.

                               

                              Then, tell us what happened, please.

                               

                              I cannot express enough contempt for XDCam EX.  It's one of the lamest codecs of all time; almost as bad as HDV: Long-GOP, 420, 8-bit... It's my Lex Luthor.  My Kryptonite.  When I was working in FCP+AJA with an XDCam EX job, I finally learned that I'd be time and aggravation ahead if I'd just transcode all my footage to ProRes before I started editing.

                               

                              I still get a lot of XDCam EX to work with.  Usually from my low-budget clients.  Always for non-broadcast, web, DVD, convention videos, etc, where nobody cares if the video is over 100.  I hate it less in Pr.  But, then, I'm not dealing with your issue.

                              • 13. Re: Waveform monitor still shows illegal levels after using video limiter
                                CLVPRO Level 1

                                Kevin, I mentioned in the second post that sometimes there were other color effects "above the limiter". Yes I made sure the limiter was always the last effect, and just for testing pruposes, also tried changing the order.

                                • 14. Re: Waveform monitor still shows illegal levels after using video limiter
                                  CLVPRO Level 1

                                  Glenn, yes it would be nice if there was a way to lock an effects order in future versions. Depending on the desired effect, sometimes the order needs to be changed. I suppose some people may even want to compress the image first, then apply additional color correct to achieve a particular look. It does seem like the default for the limiter should lock its order position as the last effect to render the file.

                                  • 15. Re: Waveform monitor still shows illegal levels after using video limiter
                                    CLVPRO Level 1

                                    Jim, I tried your test. First I had to change the uncompressed setting to 1920x1080, and to 29.97, and the field order. Then exported the clip. Once I import the clip into Premiere Pro the preview looks to be within legal range. However, just like before, once the timeline is rendered, the levels expand.

                                     

                                    Then I tried adding the limiter to the exported uncompressed avi clip. Then exported as uncompressed avi again. Imported that clip and just as before, looks legal during preview, but after render it expands. Also interesting to note that the uncompressed avi clip was over 6 GB for a 39 second clip.

                                     

                                    I feel your pain Jim. I usually enjoy color grading, but this has been driving me crazy. I'm not going to stress over it anymore, and just going to do the color correction using the scopes and my eyes as the guide, before rendering. I'll just have to let the duplication/captioning folks clean it up for broadcast. If I find out anything of interest, I will post here in the forum.

                                    • 16. Re: Waveform monitor still shows illegal levels after using video limiter
                                      Jim Curtis Level 3

                                      Well, it's great that you have a back-up plan.

                                       

                                      I was trying to determine if it was the codec that was causing your issue.  But, if you're getting the same results with an uncompressed AVI all the way, that sure seems to point to Pr, or something else as the culprit.

                                       

                                      I was getting some scaling down after rendering earlier in the year (also using XDCam EX footage), and I never found a fix for it, other than to scale my footage up a few percent.  That wasn't the answer I was hoping for, but I got my work done.  I reported the bug to Adobe, and am hoping it gets fixed for CS6.

                                      • 17. Re: Waveform monitor still shows illegal levels after using video limiter
                                        Stephen_Spider Level 3

                                        Try turning off maximum bit depth for sequence.

                                        • 18. Re: Waveform monitor still shows illegal levels after using video limiter
                                          CLVPRO Level 1

                                          I tried turning off Maximum Bit Depth, but still have the same problem. I typically edit and grade with maximum bit depth on so that I can see the whole signal, and if processing effects, it minimizes banding and artifacts.

                                          • 19. Re: Waveform monitor still shows illegal levels after using video limiter
                                            CLVPRO Level 1

                                            Jim glad you reported the bug to Adobe. I gave up on contacting Adobe years ago. I asked them when Premiere Pro and the CS suite was going to be 64 bit, and my response was that there wasn't a demand for it and they were going to wait till there was. Well they finally listened years later, not because one customer but because of the whole industry. I'd rather spend my time talking to users that actually have to use and know the software instead of a company whose primary goal is to make money. I don't blame Adobe, they didn't invent capitalism.

                                            • 20. Re: Waveform monitor still shows illegal levels after using video limiter
                                              Stephen_Spider Level 3

                                              Maybe completely uninstalling nvidia drivers and reinstalling?

                                              • 21. Re: Waveform monitor still shows illegal levels after using video limiter
                                                shooternz Level 6

                                                I guess somewhat related.... so here is my NEW "legalising video for broadcast workflow".

                                                 

                                                (Its NEW because our broadcast QC gatekeepers have tightened up a lot recently and promised to get tougher - including audio loudness)

                                                 

                                                I export my video sub master ( uncompressed QT) and check it in Da Vinci Resolve. (with the scopes)

                                                 

                                                The export is almost always illegal some where some how.

                                                 

                                                I have found the scopes and FX in Premiere in adequate for the task of legalising video at broadcast QC level.

                                                 

                                                So...In Da Vinci  Resolve...I set the scope Limiter settings  to 64 - 940 (10bit) and use Soft clips on the RGB curves to make them conform.

                                                 

                                                This works great and its quick!

                                                 

                                                I have a  Da Vinci Project set up as a preset , just for the task.

                                                • 22. Re: Waveform monitor still shows illegal levels after using video limiter
                                                  CLVPRO Level 1

                                                  Sounds like a good workflow. Would this process work in Da Vinci Resolve Lite (the free software version)? Can't afford the full version anytime soon, although it would be awesome to have with the full controller.

                                                  • 23. Re: Waveform monitor still shows illegal levels after using video limiter
                                                    shooternz Level 6

                                                    I am using Da Vinci Resolve Lite. 

                                                     

                                                    It is fully functional up to HD ( ie no 2k or 4k)

                                                     

                                                    I do not use a control surface with it (yet).  It is super easy to use from the GUI ( mouse control) and very responsive to subtlety.

                                                     

                                                    This is an awesome CC & Grade  application in every respect and it blows the current plugins right out of the water.

                                                     

                                                    BTW: A very cool marketing ploy by BM to meet the prospect of Adobe 'Speedgrade"

                                                     

                                                    My hopes are very high for Speedgrade but Adobe must meet the challenge of simple things likes "professional scopes and functions fpr "legalising video"

                                                     

                                                    Its a new "standard"  for broadcast digital media and Adobe needs to get into it from the get go.

                                                     

                                                    Hope you are listening Todd and Kevin?

                                                    • 24. Re: Waveform monitor still shows illegal levels after using video limiter
                                                      rowancloete Level 1

                                                      I recenty found that a project I hace been working on in Premiere CC, would fail automated QC for gamut errors, despite applying Video Limiter set to EBU limits:

                                                       

                                                      Reduction Axis: Chroma and Luma

                                                      Luma min: -1%

                                                      Luma max: 103%

                                                      Chroma min -5%

                                                      Chroma max: 105%

                                                       

                                                      I was fully expecting that the limiter would hard clamp at the levels specified (as in the good ol' days of FCP7's bulletproof Broadcast Safe). Looking at the YUV vectorscope and RGB parade confirms that the filter is not behaving as I would expect for chroma - color sneaks beyond legal limits all over the place, though reds get destroyed by the limiter - hard ugly artifacting clamping for anything approaching illegal. So it's doing something, but not what it should. Luma clamps perfectly and as expected. The Video Limiter is applied to an adjustment layer over my entire project. Interestingly, drop a Color Balance Color Correction filter (with no adjustment) onto the same adjustment layer with the Video Limiter, and chroma gets clamped properly, though at the expense of GPU acceleration (Video Limiter is GPU accellerated, Color Balance is not). Dropping the 32bit Video Limiter rendering to 8-bit with the addition of the Color Balance filter to the stack, effectively disabling the GPU accelleration of the Video Limiter, seems to fix it. Tradeoff - slow, non-GPUaccellerated exports.


                                                      Codec is XDCAM HD 422

                                                      Mac Pro 6,1

                                                      OSX 10.9.5

                                                      • 25. Re: Waveform monitor still shows illegal levels after using video limiter
                                                        Jim Curtis Level 3

                                                         

                                                        Reduction Axis: Chroma and Luma

                                                        Luma min: -1%

                                                        Luma max: 103%

                                                        Chroma min -5%

                                                        Chroma max: 105%

                                                         

                                                         

                                                        Your limits here are illegal.  Set your Luma to 100% or less, and Chroma Max to 75 or 100%, depending on the specs of your media distributor (some want 75% max chroma). 

                                                         

                                                        I don't like to use video limiters.  I correct shot by shot, and ensure my luma and chroma are in range by the scopes in Pr.  I haven't had a spot rejected yet out of hundreds for illegal luma or chroma.

                                                        • 26. Re: Waveform monitor still shows illegal levels after using video limiter
                                                          rowancloete Level 1

                                                          Hi Jim.

                                                           

                                                          Thanks for the input. What constitutes legal for the distributor is not the point of my post, it is to answer CVLPRO’s original question:

                                                           

                                                          "I was wondering why the YC Waveform monitor sometimes still shows illegal levels (past 100 IRE) even when a video limiter effect is used on the clip."


                                                          The simple answer being the video limiter in Premiere does not work as it should when GPU-accellerated, and does work properly when not. Add a Color Balance Color Correction Filter with the Video Limiter to an adjustment layer over the footage to be limited and you achieve the desired result.

                                                          • 27. Re: Waveform monitor still shows illegal levels after using video limiter
                                                            CLVPRO Level 1

                                                            The more things change the more they stay the same. Five years later from the original post and we still have the same issue. Apparently it's in the way the GPU handles the footage in Premiere Pro. Seems like adding a non-adjusted Color Balance Color Corrector filter and Video Limiter (with desired levels) is the easiest way to grade to specs. That's less steps than rending out the whole timeline and running it though Speedgrade, Color Finesse or Da Vinci. Thanks everyone for the input over the years. Half a decade of work on this matter is an accomplishment, hahaha.

                                                            • 28. Re: Waveform monitor still shows illegal levels after using video limiter
                                                              I Mix Hitz

                                                              Still having this same problem tonight. So frustrating. Called Adobe and they gave me the 52 fake-out. @ hours for absolutely nothing. I'm now just rendering out, dumping into Sony Vegas (keep quiet) and adding their B'cast safe. No issues. BUT, tired of having to use a workaround. Yes, using MXF but that's what the network (Fuse) asks for.

                                                               

                                                              PLEASE FIX!!

                                                              • 29. Re: Waveform monitor still shows illegal levels after using video limiter
                                                                shooternz Level 6

                                                                Use Levels Effect for better results.

                                                                 

                                                                Video Limiter in PPro has always sucked.

                                                                • 30. Re: Waveform monitor still shows illegal levels after using video limiter
                                                                  Jim Curtis Level 3

                                                                  shooternz wrote:

                                                                   

                                                                  Video Limiter in PPro has always sucked.

                                                                   

                                                                  I've not been able to make it work without uglifying my video.  Seconded.

                                                                  • 31. Re: Waveform monitor still shows illegal levels after using video limiter
                                                                    Michael Tiemann Level 1

                                                                    I just been bitten by this, too.  I created a LUT in SpeedGrade to match video to an image.  In my Program Monitor, it looks great.  But in my scopes, I've got reds at the -30 level.  When I render out, I get horrible, horrible artifacts.  It boggles my mind that the Program monitor can lie so well, and that the (GPU-accelerated) renderer cannot.

                                                                    • 32. Re: Waveform monitor still shows illegal levels after using video limiter
                                                                      chrisw44157881 Level 4

                                                                      shooternz is right, levels have no bug. I made a broadcast safe preset that will not only legalize all video to lumin 16-235

                                                                      but also fix chroma to 90% YUV and fit in all boxes of vectorscope YUV!

                                                                       

                                                                      premiere 2015.2 broadcast safe preset

                                                                      premiere pro cc 2015.2 broadcast safe preset - Creative COW