9 Replies Latest reply on Dec 1, 2013 5:35 PM by RousselG

    Why AE clipped value above 100 ire

    RousselG Level 1

      Hi,

      .mov seem to have some clipping happening on import or export from after effects.

       

      i'm getting proresHq clip out of premiere to blur a face, and then i export for the grading in resolve in proresHQ. In Premiere CC, i see those overbright (above 100ire), they are not clip. But this doesn't seem to pass on in after effetcs. I try with the original .MXF, no chance. I mess a lot with Color management. And same thing in CS6. So far, i put my projet in 32bits and then drop my output white to retain a maximum of signal for the colorist.

      But this is not a viable solution.

      I always thought i could import a .mov in after effects, then render in the same codec and obtain the same signal.

      What have I missed? Is this a bug, is this a feature?

      How can AE, when in 32bits, sees those value but can not write them back on export, in the same codec?

       

      thank you

        • 1. Re: Why AE clipped value above 100 ire
          Fuzzy Barsik Level 4

          I don't know if it's a bug or a feature, but that's how things work in Adobe Suite: superwhites are clipped on encoding to a production codec, while they are preserved to some extent on encoding to H.264. I hope, Todd or Mylenium will be able to shed some light from technical point of view.

           

          As you noticed, you may have better luck with preserving superwhites, if you compress the range (similar to yours another one workaround is to assign Rec.709 16-235 colour profile on exporting).

           

          You may also try DPX with 'Over Range' settings. Meanwhile, the best result I could I was able to get with exporting to OpenEXR 32-bit - this way superimposing a layer out of transcoded footage with blending mode set to Difference in 32-bit linearised working space results in pure black solid, i.e. all pixels values are mathematically identical.

          • 2. Re: Why AE clipped value above 100 ire
            Todd_Kopriva Level 8

            I'm not sure that I understand your message.

             

            Please tell me exactly where in the After Effects process you are and are not seeing the correct overbright values. Please be as detailed as possible.

            • 3. Re: Why AE clipped value above 100 ire
              RousselG Level 1

              Thanks for joined in todd!

              and thank you Fuzzy, I seem to have the same problem as you had before

               

              Simply put...

              I'm in Premiere CC and the cut looks like this in the Waveform, with overbright value above 100 ire;

              source.png

               

              I export that clip in prores to do a quick comp in AE. By the way, i have reimport the same clip upon export to validate, and the prores still have thoses superwhites back in Premiere.

              In AE, in 32bits, no ColorManagement, drop that to make a new comp. render this to a Prores.

               

              Back in Premiere, import, and here's my waveform with clipped white

              AE32bts.png

               

              ? I always thought that simple workflow would have kept those overbright values?

              If not, how could I?

              I have played with color management, and as Fuzzy mention above, HDTV16-235 colorspace, compress the signal so everything is there. But it is always a shame to explain to an editor or colorist that this clip is exacly the same but compress into smaller value. I wish the clip as visually simillar.

              I try with overange DPx, but no chance, this was only a fisrt try, i'll may had to dig a little deeper. EXR was the next step.

               

              My goal was to keep the same codec to simplify the Online process. For now, i ask the Online editor to drop the whites before exporting.

               

              Thank you

              • 4. Re: Why AE clipped value above 100 ire
                Todd_Kopriva Level 8

                Is the entire color range still present when you're working in After Effects? I.e., are the overbrights only being lost on export?

                • 5. Re: Why AE clipped value above 100 ire
                  RousselG Level 1

                  In 32bits, if i fireup color finesse, i can gain down and yes, recovered the overbright. So i assume it is on export.

                  But i am confuse on how Premiere can encode those value to the same codec and not AE.

                  • 6. Re: Why AE clipped value above 100 ire
                    RousselG Level 1

                    Hi again,

                    here are some developpement that will bring mostly confusion...

                    the overbright clipping doesn't happen when rendering with Adobe media encoder from a after effects comp in 32bpc.

                     

                    so here's my workflow.

                     

                    1. My MXF in Premiere with above 100 IRE value

                    sourceMXF copy.jpg

                     

                    2. My MXF export as proresHQ and reimport in Premiere, still with value above 100 IRE

                    prores-premiere-reimport.jpg

                     

                    3. Clipping occuring when the shot is exported from after effects (same codec, no effects apply)

                     

                    in 16bpc, and 32bpc

                    AE-proresExport16b.jpg

                     

                    4. No clipping with the same comp, but render with Adobe Media Encoder (add to AME render queue from AE in 32bpc... it clip in 16bpc )

                    ame-32b.jpg

                     

                    Interesting?

                    Can we have the same renderer in After Effects?

                    • 7. Re: Why AE clipped value above 100 ire
                      brausinger

                      Hi,

                       

                      are there any news concerning this topic? Ive just encountered the same problem. My client sent my some files with over-bright highlight information. I wasn't aware of that and did a regular comp job. Now I am not able to render the project with the over-bright information. I rendered the AE project in AME. Project Setting are 32bpc, Woring Space sRGB and linearized Woring Space on. The resulting movie is darker. I guess AME "compressed" the highlight information. Did you guys encouter the same result or is there a possibility to render the file with overbrights (so that it is not getting darker)?

                      I ve also rendered a exr sequence in 32bpc. Thats worked pretty well, all the information is included in the exr. But now Im kind of stuck because I can not turn the exr in a mov file while not loosing the overbrights.....

                       

                      Did you guys manage to find a workaround?

                       

                      Thanks for the reply,

                       

                      best

                      • 8. Re: Why AE clipped value above 100 ire
                        Fuzzy Barsik Level 4

                        Your issue as you described it is not related to clipping overbrights, it is related to the question that neither PrPro nor AME is a colour manageable application and can't properly interpret data in linear gamma.

                         

                        So as to be able to send your AE composition from a project with linearised working space to either PrPro or AME via Dynamic Link you need to go back from linear working space to gamma corrected. How to do that without ruining all your work? Easy: drop your working comp into another one, go to View -> Use Display Color Management and disable it, then apply Color Profile Converter onto pre-comp layer (former your working comp) and set Input Profile to 'Project Working Space' while Output Profile to 'sRGB' or 'HDTV (Rec.709)'.

                        • 9. Re: Why AE clipped value above 100 ire
                          RousselG Level 1

                          Hi Brausinger,

                          I just tested my past workflow and this clipping hasn't been fixed in the last CC october update.

                           

                          For the darker rendering, i'll go with Fuzzy, it is more a color management issue.

                           

                          As for workaround, I now render a Log DPX.