I originally (mistakenly) filed this on bugs.opencompositing.org

I was using the latest git of compiz until the settings upgrades. I've downgraded to 0.5.2 and the problem remains. I'm using gentoo, xgl on ati fglrx, and the xeffects overlay.

I've patched mplayer with the latest patch from the mailing list to use the compiz xv output and I've patched XGL to allow 8 bpp alpha only GLX pixmaps.

The result is an odd white screen for the video output. If I turn down the
opacity on the window I can make out the image in black and white. 

If I turn off YV12 colorspace in the options for the video plugin, then I can
see the video normally.

I'm not sure what I need to do to help debug this, so if you need any more
detail (and you probably will...) then please ask.

xorg.conf: 
#Section "Extensions"
#       Option "Composite" "Enable"
#EndSection

Section "ServerLayout"
        Identifier     "X.org Configured"
        Screen      0  "RadeonScreen" 0 0
        InputDevice    "Mouse0" "CorePointer"
        InputDevice    "GlidePad" "AlwaysCore"
        InputDevice    "Keyboard0" "CoreKeyboard"
        Option  "BlankTime"  "5"  # Blank the screen after 5 minutes (Fake)
        Option  "StandbyTime"  "10"  # Turn off screen after 10 minutes (DPMS)
        Option  "SuspendTime"  "20"  # Full suspend after 20 minutes
        Option  "OffTime"  "30"  # Turn off after half an hour
#       Option "AIGLX" "true"
EndSection

Section "Files"
        FontPath    "/usr/share/fonts/misc:unscaled"
        FontPath    "/usr/share/fonts/Type1"
        FontPath    "/usr/share/fonts/TTF"
        FontPath    "/usr/share/fonts/corefonts"
        FontPath    "/usr/share/fonts/freefont"
        FontPath    "/usr/share/fonts/sharefonts"
        FontPath    "/usr/share/fonts/terminus"
        FontPath    "/usr/share/fonts/unifont"
        FontPath    "/usr/share/fonts/75dpi:unscaled"
        FontPath    "/usr/share/fonts/100dpi:unscaled"
        FontPath    "/usr/share/fonts/artwiz"


EndSection

Section "Module"
        Load  "record"
        Load  "extmod"
        Load  "dbe"
        Load  "dri"
        Load  "glx"
        Load  "GLcore"
        Load  "xtrap"
        Load  "freetype"
        Load  "type1"
#       Load  "drm"
        Load  "synaptics"
EndSection

Section "InputDevice"
        Identifier  "Keyboard0"
        Driver      "kbd"
        Option      "CoreKeyboard"

        Option      "XkbModel"  "pc105"
        Option      "XkbLayout" "ie"
EndSection

Section "InputDevice"
        Identifier  "Mouse0"
        Driver      "mouse"
        Option      "Protocol" "auto"
        Option      "Device" "/dev/psaux"
        Option      "ZAxisMapping" "4 5" 
        Option      "Buttons"      "5"
EndSection

Section "InputDevice"
  Driver        "synaptics"
  Identifier    "GlidePad"
  Option        "Device"                "/dev/input/mouse_alps"
  Option        "Protocol"              "auto"
#  Option       "Protocol"              "auto-dev"
  Option        "LeftEdge"              "120"
  Option        "RightEdge"             "830"
  Option        "TopEdge"               "120"
  Option        "BottomEdge"            "650"
  Option        "FingerLow"             "14"
  Option        "FingerHigh"            "15"
  Option        "MaxTapTime"            "180"
  Option        "MaxTapMove"            "110"
  Option        "EmulateMidButtonTime"  "75"
  Option        "VertScrollDelta"       "20"
  Option        "HorizScrollDelta"      "20"
  Option        "MinSpeed"              "0.2"
  Option        "MaxSpeed"              "0.5"
  Option        "AccelFactor"           "0.01"
  Option        "EdgeMotionMinSpeed"    "15"
  Option        "EdgeMotionMaxSpeed"    "15"
  Option        "UpDownScrolling"       "1"
  Option        "CircularScrolling"     "1"
  Option        "CircScrollDelta"       "0.1"
  Option        "CircScrollTrigger"     "2"
  Option        "SHMConfig"             "on"
  Option        "Emulate3Buttons"       "on"
EndSection


Section "Monitor"
        Identifier   "Monitor0"
        VendorName   "Monitor Vendor"
        ModelName    "Monitor Model"
        Option "DPMS" "true"
EndSection

Section "Device"
        Identifier  "ATI"
        Driver      "fglrx"
        BusID       "PCI:1:0:0"
        Option      "VideoOverlay" "on"
        Option      "OpenGLOverlay" "off"
        Option      "UseInternalAGPGART" "no"
EndSection

Section "Device"
        Identifier "ATI Radeon"
        Driver "radeon"
        # this may solve some issues
        #Option      "BusType" "PCI"

        # acceleration
        Option          "AGPMode" "4"
        Option          "AGPFastWrite" "no"
        Option          "EnablePageFlip" "on"
        Option          "RenderAccel" "on"
        Option          "AccelMethod"   "EXA" # or XAA
        Option          "BackingStore" "true"
        Option          "XaaNoOffscreenPixmaps" 
        Option          "ExaNoOffscreenPixmaps" 
        Option          "DRI" "true"

        # enable (partial) PowerPlay features
#        Option          "DynamicClocks" "on"

        # use bios hot keys on thinkpad (aka fn+f7)
        # Option          "BIOSHotkeys" "on"

        # enable radeon specific xinerama
        #Option          "MergedFB" "true"
        #Option          "CRT2Position" "RightOf"
        #Option          "CRT2Hsync" "50-75"
        #Option          "CRT2VRefresh" "30-82"
        #Option          "MetaModes" "1024x768-1280x1024"
        #Option          "MergedNonRectangular" "true"

        # Color Tiling
 #       Option          "ColorTiling"   "on"

        # Video overlay
        #Option          "OverlayOnCRTC2"        "on"

EndSection

Section "Screen"
        Identifier "RadeonScreen"
        Device     "ATI"
#       Device     "ATI Radeon"
        Monitor    "Monitor0"
        DefaultDepth 24
        SubSection "Display"
                Viewport   0 0
                Depth     24
        EndSubSection
EndSection

Section "DRI"
        Group 0
        Mode 0666
EndSection