Paresh, Alpha channels allow imagery to be composed with transparency, so that the original image still shows through to some extent behind the newly-applied stuff. This is called alpha-blending, and is used to render text more prettily, amongst other things.
The X11 RENDER extension is supported by VNC Enterprise Edition servers, but not by the current VNC Free Edition, although I believe that many Linux distributions have modified Free Edition servers that also support RENDER. Regardless of whether RENDER is enabled, the desktop framebuffer will still use depth 24, since it doesn't need an alpha channel. Cheers, -- Wez @ RealVNC Ltd > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of paresh masani > Sent: 26 June 2008 12:22 > To: James Weatherall > Cc: Corne Beerse; vnc-list@realvnc.com > Subject: Re: 24-bit color support to Xvnc > > James, > > I think you are missing something here. Google tells me ( > http://en.wikipedia.org/wiki/Alpha_channel) that Microsoft > makes use of this upper 8 bits. however, I found that X11 > only uses these bits as part of XRender and RealVNC doesn't > seem to support XRender. Am i correct? > > Thanks, > Paresh > > > On 6/20/08, James Weatherall <[EMAIL PROTECTED]> wrote: > > > > Paresh, > > > > That means that your Windows desktop is using depth 24 at 32 > > bits-per-pixel, not depth 32 - depth refers to the number > of bits of > > actual colour information per pixel, while bits-per-pixel refers to > > the size of data element used to store the pixel values. > > > > The standard format for the "Highest (32-bit)" setting in > Windows is 8 > > bits for each of the red, green and blue components, with the 8 > > remaining bits unused(*). > > > > -- > > Wez @ RealVNC Ltd > > > > (*) Actually, they might be used for alpha-channel, > Z-buffer or other > > auxilliary data, but in VNC-land, we normally just count > the RGB bits > > towards the "depth". > > > > > > > -----Original Message----- > > > From: paresh masani [mailto:[EMAIL PROTECTED] > > > Sent: 20 June 2008 09:18 > > > To: James Weatherall > > > Cc: Corne Beerse; vnc-list@realvnc.com > > > Subject: Re: 24-bit color support to Xvnc > > > > > > Yes James...I have set the screen resoulution to > Higesh-32 bit color. > > > > > > Thanks, > > > Paresh > > > > > > > > > On 6/19/08, James Weatherall <[EMAIL PROTECTED]> wrote: > > > > > > Paresh, > > > > > > Are you sure that the machine on which you're using > VNC Viewer > > > supports > > > depth 32, and not depth 24 at 32 bits-per-pixel? > > > > > > -- > > > Wez @ RealVNC Ltd > > > > > > > > > > -----Original Message----- > > > > From: paresh masani [mailto:[EMAIL PROTECTED] > > > > Sent: 19 June 2008 14:32 > > > > To: Corne Beerse > > > > Cc: James Weatherall; vnc-list@realvnc.com > > > > Subject: Re: 24-bit color support to Xvnc > > > > > > > > Thanks a lot for much clarification. Means Xvnc will not > > > > supprot 32bit color ever. Is it possible? because my > > > > vncviewer can run at 32-depth but Xvnc doent support > > > 32-depth. why?? > > > > > > > > Thanks, > > > > Paresh > > > > > > > > > > > > > > > > > > > > _______________________________________________ > VNC-List mailing list > VNC-List@realvnc.com > To remove yourself from the list visit: > http://www.realvnc.com/mailman/listinfo/vnc-list > _______________________________________________ VNC-List mailing list VNC-List@realvnc.com To remove yourself from the list visit: http://www.realvnc.com/mailman/listinfo/vnc-list
