7 Replies Latest reply on Mar 1, 2012 1:30 PM by bogiesan

    Bad quality sections in render

    Morric603

      Hi,

      I have made an animation in AAE (Four minutes long) but have a problem with rendering. I add to render queue, have tried to export as a .flv and a .mov, but both times, a small 20 second section in the second half of the video has a massive detiriation in quality... (Think of the old YouTube). This always happens in the same place; and has happened once before in a different project. What going on? How can I fix it?

      Thanks

        • 1. Re: Bad quality sections in render
          Mylenium Most Valuable Participant

          Could be anything from bad source footage interpretation to unfavorable compression patterns in the source footage not resulting in a sharp decode to sub-pixel placment (fractional values) to OpenGL and/or a specific plug-in kicking in at this point. Impossible to tell without more info.

           

          Mylenium

          • 2. Re: Bad quality sections in render
            Morric603 Level 1

            Erm... Well it works fine when RAM previewing, What more info would you need?

            • 3. Re: Bad quality sections in render
              Mylenium Most Valuable Participant

              Well, composition size and frame rate, what kind of sources are involved, what effects... And things working in RAM preview doesn't realyl mean anything. Some effects work differently on teh render queue if e.g. they revert to software only mode instead of using OpenGL or doing temporal analyses that they don't do while working. Similarly, enabling field rendering, motion blur and otehr stuff can have a massive effect on effects that respond to these specific features...

               

              Mylenium

              • 4. Re: Bad quality sections in render
                Morric603 Level 1

                Ok,

                Comp size: 1280 x 720

                Frame rate: 29.97 FPS

                Duration: 0;04;21;02

                Sources: All either .bmp, .mp3, or .mov

                No effects

                No motion blur at that time

                Field render: Off

                No Proxies

                Quality: Best

                .flv On2 VP6 codec

                1600kbps bitrate

                No resize or crop

                Preserve RGB off

                Colour management: off

                Including project link

                Not including XMP Metadata

                Exporting to folder on :C Drive

                Rendering Plugin: Advanced 3D

                Rendering in OpenGL using a NVIDIA GeForce GTX 460 2000mb memory. All capabilities supported.

                Multiprocessing disabled

                8 gb RAM in Windows 7 Home Premium (1.5 reserverd for system)

                 

                 

                I hope that is enough?

                • 5. Re: Bad quality sections in render
                  bogiesan Level 4

                  >  This always happens in the same place;<

                   

                  There is something at that spot, that precise frame. It is a source item or precomp.

                   

                  My workflow never uses AE to do heavy compression or transcoding. I'd be rendering out to a standard codec and then bring that movie back into Adovbe Media Encoder to get the flv output.

                  • 6. Re: Bad quality sections in render
                    Morric603 Level 1

                    Yes, it seems to be a particualr Pre-comp... What do you mean by render to standard codec?

                    Thx

                    • 7. Re: Bad quality sections in render
                      bogiesan Level 4

                      You're rendering to flv, that's not a standard video codec, it's a wrapper, just like AVI or QT. Mostly, FLV is using a highly compressed codec.

                      Looking at your list of footage items, the mp3 might be causing this glitch since it has to be decompressed on the fly during the render.

                       

                      from wiki:

                       

                      Flash Video FLV files usually contain material encoded with codecs following the Sorenson Spark or VP6 video compression formats. The most recent public releases of Flash Player (collaboration between Adobe Systems and MainConcept) also support H.264 video and HE-AACaudio.[4] All of these compression formats are currently restricted by patents.