9 Replies Latest reply on May 26, 2009 9:32 PM by Adolfo Rozenfeld

    Poor Gradients Rendering to Flash

    CantonVideoMan Level 1



      I am rendering a composition in AE CS4 in multiple formats. In the composition we have a layer (transparent background) that is a shadow (grey gradiant). When we render to QuickTime the shadow looks great. When we render the same composition to Flash all the subtleties in the shadow are lost. Lighter shadows are missing. If I darken up the shadow the shadow becomes harsh all the lighter areas are gone.


      We've tried a couple of different options with the shadow using a Photoshop file using a transparent layer with the shadow on it as well as trying a transparent PNG file. Although both formats produce slightly different results the problem remains the same, the gradient is all but lost.


      Any suggestions woulkd be greatly appreciated.





        • 1. Re: Poor Gradients Rendering to Flash
          Adolfo Rozenfeld Adobe Employee

          How are you rendering to Flash?

          Are you making a FLV file from the Render Queue?

          What preset/frame size/codec/data rate are you using?

          • 2. Re: Poor Gradients Rendering to Flash
            CantonVideoMan Level 1



            I am making an FLV file from the render queue (RGB+Alpha). I am using a Custom preset, my frame size is 340 x 462 (same size as the Quicktime I am comparing it with). The codec is On2 VP6 (I tried Sorenson Spark but it wouldn't produce transparency). The data rate is CBR 1,500 kbps.





            • 3. Re: Poor Gradients Rendering to Flash
              Adolfo Rozenfeld Adobe Employee

              This seems to be caused by the alpha channel encoding, and how the premultiplied alpha is matted with color.

              I am far (very far) from being a Flash expert, but I understand the Flash authoring app only handles alpha as premultiplied (anybody knows if this is the case)

              If so, before exporting, make sure the background color in the Comp is black and leave the alpha as Premultiplied. Then if you bring back the file into AE, make sure it's also interpreted as Premultiplied.

              • 4. Re: Poor Gradients Rendering to Flash
                elaine montoya Level 3

                Hi Bob,


                Why don't you give this a try....


                With your AE file open:

                1. go to File > Export > Adobe Flash Professional (XFL) settings

                2. make sure rasterize to: Format: FLV is selected

                3. click format options and set your settings as needed.

                4. because you have transparency, make sure you are using the On2 VP6 codec

                5. click OK

                6. and in the first window, click OK again

                7. save to your export destination

                8. double click to open this file in Flash


                See what your results look like when exported this way and opened in Flash.


                Let me know the results. I have found that XFL exports tend to keep the graphics looking truer.


                Finally, if this doesn't work, simply take the QuickTime you exported and convert it to an FLV in Adobe Media Encoder.


                good luck!


                1 person found this helpful
                • 5. Re: Poor Gradients Rendering to Flash
                  Adolfo Rozenfeld Adobe Employee

                  Elaine: I think it's just a matter of the color matting going through the premultiplied alpha.

                  When you have a white background, and export a Quicktime file, the premultiplied alpha is correctly matted with white.

                  Maybe Flash authoring requires the premultiplied alpha to be matted with black when exporting with alpha, and this is why AE is always using black.


                  Simple test to confirm this: if you bring the FLV back into After Effects and go to Interpret Footage > Main, you'll surely see it's interpreted as premultiplied, matted with black. If you click in the color swatch and change it to white (the same color in the Comp), the gradients should look great again.


                  Unfortunately, Flash authoring doesn't have an Interpret Footage option, so you want to set the background color to black before exporting.

                  • 6. Re: Poor Gradients Rendering to Flash
                    CantonVideoMan Level 1

                    Hi Elaine & Adolfo,


                    Elaine's suggestions were helpful. I did try the XFL export but as far as I could tell no resize option was available. The result was great but I could not resize it from AE. I might be able to resize it in Flash. BUT I took the QuickTime File that was rendered from AE (At the size I needed) and rendered a FLV file in the media encoder....FANTASTIC!!! it worked!!! The file size went up from 8.8 MB to 12 MB which isn't insignificant working with web media but at least I have the quality I need, now I can work on reducing my file size :-) Thank you Elaine!


                    Adolfo, I'll also try your suggestion as well and report the results back. Thanks again for the feedback

                    • 7. Re: Poor Gradients Rendering to Flash
                      Adolfo Rozenfeld Adobe Employee

                      I am glad it worked!

                      (still, the culprit was that the background color wasn't used for color matting in the premultiplied alpha).

                      AME as a standalone application is a more convenient solution anyway, since it gives you access to more advanced encoding features like 2-pass with Variable Bit Rate, etc.

                      • 8. Re: Poor Gradients Rendering to Flash
                        CantonVideoMan Level 1



                        Changing the background color of the composition to black was the trick! I ended up with a great looking gradient in the shadow and the smallest file size to date on this comp (8.1 MB). Being able to render for AE in the render queue is definately preferred for me (less steps).


                        Thank you very much!


                        Elaine, thank you for your feedback. Some of your "tricks" may be helpful on future projects.





                        • 9. Re: Poor Gradients Rendering to Flash
                          Adolfo Rozenfeld Adobe Employee

                          It's great that it worked for you. And now we know what the problem was.

                          Note that normally, when exporting to any format with alpha, you shouldn''t have to change the background color. AE takes care of setting the right color for matting in the premultiplied alpha. This is why your Quicktime movie worked well from the start.

                          I am investigating if having it matted as black is required by Flash authoring, because if it isn't, this could be a glitch.