1 Reply Latest reply on Jul 28, 2015 9:11 AM by Mylenium

    aliasing problem on mp4 exports


      Hello everyone !


      I'm working on an animation in After Effects, I didn't know where the animation will be played so I worked it in HD, 1920x1080.


      So when I want an export, I put my composition in the render queue and I export it in optimal settings, QuickTime format. So far there are no worries, but when I have to send it to validation people (with a webplayer) I need a 800x450 resolution, so I put my QuickTime export in Adobe Media Encoder, set the resize, choose the H264 format (VBR 1, 3Mbits/s), and I render the file.


      But after the rendering comes the problems... Big aliasing problems ! I have try 10 or 15 way to export it, with different formats, different sizes, different codecs... Nothing but just this nasty stairs made out of pixels :


      (the original .mov, played in QuickTime)



      (the exported mp4 played in QuickTime)



      (the exported mp4 played in windows media player)




      In a web browser the aliasing is just too dirty, worst than in windows media player... Do you know a way to export an After Effects animation in .mp4 with no aliasing problem ?


      I hope someone will explain me what is this mess, thank you in advance ! :-)


        • 1. Re: aliasing problem on mp4 exports
          Mylenium Most Valuable Participant

          Fringes in compressed footage mean that the contrast is too extreme and it causes signal feedback or clipping in the compression algorithms. At best you can try tweaking the colors and desaturate them a bit, but quite honestly - large uniformly colored areas will always be problematic. It simply goes against how MPEG compression works. Adding some noise might help, but otherwise you will have to live with this limitation.