11 Replies Latest reply on Feb 23, 2014 6:04 PM by fastnoc

    Help with results (degraded results)

    fastnoc Level 1

      I'm not sure how to describe this.

       

      When i render I'm finding issues I can't quite pin down.

       

      I'm getting a sort of 'banding' issue. Its the same results youd get if you tried to save a gif file with a gradient, jsut not as pronounced.

       

      I've got a couple examples to show. But know ahead of time, you'll probably need to let this load. I didn't want to upload to youtube and have them compress thee files even more.

       

      These are mp4, but the original lossless avi file shows the same thing.

       

      look where i have black in the background, and on the first video note the banding thing i'm referring to over the face of the chrome text when it's in a shadow

       

      http://mindzipper.com/newsite/sample/

       

      i'm just not sure what to even look at here. I don't see this when it's in After Effects.

       

      any help is appreciated

        • 1. Re: Help with results (degraded results)
          Mylenium Most Valuable Participant

          Yeah, H.264/MP4 is 8bit, uses chroma undersampling and a block compression plus certain encoders may mess with Gamma even if you use high data rates. So what? Inevitably you are going to see artifacts. Certain types of imagery just don't lend themselves particularly well to this and all the tricks in the world can't fix it and very dark content with gradients/ vignettes across  the entire area are just that - you simply exhaust the math and hit walls in the compression algorithms.

           

          Mylenium

          • 2. Re: Help with results (degraded results)
            fastnoc Level 1

            Thanks for the reply!

             

            I don't think you understood all of what i said though. i rendered it to mp4 so i could show it. but that same problem exists in the .avi file.


            It may get more pronounced, i mean we know that compression has a cost, but the problem is the same on the original file that was rendered lossless.


            I should clarify, i'm nto saying there's a problem withe the software etc. it's something I am doing wrong, i just don't know what that is so i thought maybe someone else had the same problem. I have gone trhough everything I do and nothing comes to mind that would cuase it.

            • 3. Re: Help with results (degraded results)
              Rick Gerard Adobe Community Professional & MVP

              The banding I see is just 8bit banding. There's not enough separation in values to get a smoother gradient. Simple as that.

               

              The solution is to add a bit of noise to your shot to hide the banding or to work in 32 bit right up to the final compression. You might still need a bit of noise even with a 32 bit project.  Also note that if your monitor is not capable of high enough color depth you'll see banding in 32bit projects because of the color depth of the monitor. This is a problem we have all had to live with for a very long time.

               

              Check out this tutorial fro Greyscale Gorilla:

              http://greyscalegorilla.com/blog/tutorials/how-to-remove-banding-artifacts-in-after-effect s/

               

              A Google search will bring up lots of other solutions. This is a very common problem.

              1 person found this helpful
              • 4. Re: Help with results (degraded results)
                fastnoc Level 1

                Interesting. i'll have to research this a little.

                 

                As for the monitor that shouldn't be the problem. I have a $1000 Dell u3014 30" monitor. I've played with the profiles too thinking that might be it.


                What you say makes perfect sense on the mp4. what i struggle with is it's showing on the AVI that was rendered lossless, so that's why i'm confused. i originally thought i was doing something wrong rendering, then i looked and it's on both.

                 

                I render to avi lossless, then put the resulting file into AME to render to mp4 for upload. I'd upload the original but it's 13g i believe and I'm sure you don't want to download that.

                 

                So tired i'm cross eyed right now but I'll review your link in the morning.

                 

                thank you very much!

                • 5. Re: Help with results (degraded results)
                  Rick Gerard Adobe Community Professional & MVP

                  8 bit is 8 bit... You only have 256 total values available for each channel so if your brightest blue is 10 and your darkest blue is 5 in a dark gray gradient and the gradient is 100 pixels wide then you are going to have a bands of colors that are 20 pixels wide and they are going to show up no matter what you do unless you fool the eye on the edges by adding a little noise. Change the image to 32 bit and you have thousands and thousands of different values available over those 100 pixels so there is no banding, unless you look at the image on an 8bit monitor. Then, you're back to the same problem.

                   

                  Your monitor is a 12 bit device so it is still limited but way better than 8, so any banding problems you may be seeing may be traced to your graphics adaptor. What is that set to??? Make sure you are pushing as many colors as you can to your nice display.

                  1 person found this helpful
                  • 6. Re: Help with results (degraded results)
                    fastnoc Level 1

                    I don't think I followed where you were going, but i see it now, and you hit the nail on the head. it was set to 8bit.

                     

                    that absolutely fixed it.

                     

                    thank you so much!

                    • 7. Re: Help with results (degraded results)
                      fastnoc Level 1

                      Here's the interesting thing. i always wondered why i lost color on the final. i use a blue animated texture on the edges. but in those renders it came out white. I never undersdtood why. Now I do.

                       

                      go back to this page, and the second video is now showing 32 bit depth. and if you compre the first to the second, they are using the same exact textures. but in 32 bit depth you can FINALLY see the animated colors...

                       

                      oh boy i'm like a kid now. But i can't find where to set this. if I change the setting, every time i open or start a project it reverts to 8bit.

                       

                      anyway, check out the difference. funny thing, now that I'm rendering with the right depth I am going to have to turn down the lights, because now that they're rendering cxorretly they're way too bright.

                       

                       

                      EDIT: by the way, for comparison I put the two renders side by side in the third video. no clue why the 8bit shakes. could that be the color disparity? because i'm putting an 8bit video into a 32 bit project?  anyway. the top the original bad video. the second is a corrected, changing to 32 bit. now the colors were NOT changed. but in the 8bit version my awesome animated textures never worked. The third video is a side by side comparison. the exact same video. rendered in 8bit then 32.

                      http://mindzipper.com/newsite/sample/

                       

                      can't tell you how much i appreciate the help here.

                      • 8. Re: Help with results (degraded results)
                        Todd_Kopriva Level 8

                        > "if I change the setting, every time i open or start a project it reverts to 8bit."

                         

                        It's a project setting. If you want to always start new projects with this setting, then create a template project (.aet) with the setting as you like it, and always start new projects by opening the template project.

                        • 9. Re: Help with results (degraded results)
                          fastnoc Level 1

                          lol that's exactly what I'm doing. it's funny, iv'e created/edited/rendered 185 videos since august. and now that I know this, every single one of them is 8bit. boy is my renderr machine going to be busy for aawhile

                           

                          caveat here is chaning the color depth can drasticallly change how effects look. so it's not just a matter of changing an rendering, I have to reduce the lighting, lower the opacity on vigenette layers etc.

                           

                          what a revalation this is. I feel silly not already knowing this stuff, but i've only been using AE since July. so i am still very new.i just assumd that setting the color to 'millions of colors' would give me 16 bit and 'trillions' would set it to 32.

                           

                          This is precisely why this forum is so valuable to me.

                           

                          thank you!

                          • 10. Re: Help with results (degraded results)
                            Todd_Kopriva Level 8

                            This is why I so strongly urge people to start at the beginning and work their way through the learning materials. I know that I cover this topic in one video and one written article that you'd go through if you went through these materials:

                            http://adobe.ly/AE_basics

                            • 11. Re: Help with results (degraded results)
                              fastnoc Level 1

                              i'll look at that. i took a course but I don't remember this being covered.

                               

                              doesn't mean it didnt happen. there's  alot of info to learn when you're new.