2 Replies Latest reply on Feb 1, 2010 11:12 AM by Kirk

    Dithering for 18-bit TFT panel

    Green Belt


      I have a question about the Graphics Driver for Windows Embedded, which is created by IEGD.


      I have been trying to create a graphics driver for Windows Embedded. The system uses a 18bit TFT panel connected to the mainboard by LVDS. The Northbridge is GME965. I want to display 24-bpp true color by dithering. But it seems that IEGD-CED does not have the checkbox or something like that to implement dithering. Can I display 24bpp true color on our panel using the IEGD-created graphics driver?


      If it is possible, would you please let us know the concrete way?

      Thank you for your cooperation.


        • Re: Dithering for 18-bit TFT panel
          Brown Belt

          In the Attributes page under [Attribute Settings] on the LVDS Configuration page there is an attribute check box for Dither - Attribute 45.  I haven't tried this attribute, but thats where it is set.

            • Re: Dithering for 18-bit TFT panel
              Kirk Brown Belt



              DonLPI is correct (thank you for helping!) that attribute 45 controls dithering.  However, if you do not specify that attribute, the driver automatically turns it ON for 18bit panels so the colors look correct by default.  We allow it to be overridden if you have a panel that has a better dithering capability than the chipset.


              Additional information- the chipsets do spatial dithering by (in general) throwing out the least significant bits in the color information but then making semi-intelligent decisions on rounding up or rounding down the color for adjacent pixels.


              If you are having color issues, you may have the LVDS data lines misrouted on the board or your cable.