Re: [XFree86] XFree (4.3.0) & 32b graphics ...
Mark Vojkovich wrote: On Thu, 30 Oct 2003, Thomas Winischhofer wrote: Mark Vojkovich wrote: 32 and 24 bpp have the same color resolution (only 24 bits). If what you are seeing is banding, it's probably a driver issue. Laptop panels typically only have 18 bits of color resolution and this becomes visible if the graphics hardware isn't dithering from 24 => 18 bits. At least in the case of the "nv" driver for NVIDIA chips, there is an Option "FPDither" to turn that on. I don't know if other drivers support such options. Speaking of the "option": I mean it's ok that such an option exists (for what reason ever), but is there any good reason for not enabling dithering by default if the panel is detected as being of 18bit type and the colordepth is 24? Detect it how? There's nothing in the EDID that I'm aware of. Ah. If it can't be detected, that _is_ in fact a good reason. (I just wondered, because sis based laptops provide this info in a scratch register set by the BIOS; for TMDS panels RGB24 is assumed, for LVDS panels this info is hardcoded into the system BIOS) Thomas -- Thomas Winischhofer Vienna/Austria thomas AT winischhofer DOT net *** http://www.winischhofer.net/ twini AT xfree86 DOT org ___ XFree86 mailing list [EMAIL PROTECTED] http://XFree86.Org/mailman/listinfo/xfree86
Re: [XFree86] XFree (4.3.0) & 32b graphics ...
On Thu, 30 Oct 2003, Thomas Winischhofer wrote: > Mark Vojkovich wrote: > >32 and 24 bpp have the same color resolution (only 24 bits). > > If what you are seeing is banding, it's probably a driver issue. > > Laptop panels typically only have 18 bits of color resolution > > and this becomes visible if the graphics hardware isn't dithering > > from 24 => 18 bits. At least in the case of the "nv" driver for > > NVIDIA chips, there is an Option "FPDither" to turn that on. I > > don't know if other drivers support such options. > > Speaking of the "option": I mean it's ok that such an option exists (for > what reason ever), but is there any good reason for not enabling > dithering by default if the panel is detected as being of 18bit type and > the colordepth is 24? > Detect it how? There's nothing in the EDID that I'm aware of. Mark. ___ XFree86 mailing list [EMAIL PROTECTED] http://XFree86.Org/mailman/listinfo/xfree86
Re: [XFree86] XFree (4.3.0) & 32b graphics ...
Mark Vojkovich wrote: 32 and 24 bpp have the same color resolution (only 24 bits). If what you are seeing is banding, it's probably a driver issue. Laptop panels typically only have 18 bits of color resolution and this becomes visible if the graphics hardware isn't dithering from 24 => 18 bits. At least in the case of the "nv" driver for NVIDIA chips, there is an Option "FPDither" to turn that on. I don't know if other drivers support such options. Speaking of the "option": I mean it's ok that such an option exists (for what reason ever), but is there any good reason for not enabling dithering by default if the panel is detected as being of 18bit type and the colordepth is 24? Thomas -- Thomas Winischhofer Vienna/Austria thomas AT winischhofer DOT net http://www.winischhofer.net/ twini AT xfree86 DOT org ___ XFree86 mailing list [EMAIL PROTECTED] http://XFree86.Org/mailman/listinfo/xfree86
Re: [XFree86] XFree (4.3.0) & 32b graphics ...
32 and 24 bpp have the same color resolution (only 24 bits). If what you are seeing is banding, it's probably a driver issue. Laptop panels typically only have 18 bits of color resolution and this becomes visible if the graphics hardware isn't dithering from 24 => 18 bits. At least in the case of the "nv" driver for NVIDIA chips, there is an Option "FPDither" to turn that on. I don't know if other drivers support such options. Mark. On Thu, 30 Oct 2003, Romain MULLER wrote: > I'm quite a noob on Linux (and so with XFree86), and I'm asking myself if it > is possible to set color depth up to 32bpp or not ... In fact, all my JPEG > pictures that look pretty good on Windows (32b color depth) are ugly under > Linux 24b color depth ... And as far as I know, the 24b color depth of my > XFree may be in cause ... Any idea ? Maybe is it possible to force 32b color > depth ? > > PS : I use a Mandrake 9.1 on a Compaq Presario 736 (S3 twister 16/32MB shared > memory, 256MB RAM). > > Tidus, Looking forward your answer !!! > [EMAIL PROTECTED] > ___ > XFree86 mailing list > [EMAIL PROTECTED] > http://XFree86.Org/mailman/listinfo/xfree86 > ___ XFree86 mailing list [EMAIL PROTECTED] http://XFree86.Org/mailman/listinfo/xfree86
OT: 30bpp colour, parhelia (was Re: [XFree86] XFree (4.3.0) & 32b graphics ...)
On Thu, 30 Oct 2003, Giuliano Pochini wrote: > AFAIK there are not graphic cards with colour depth >24. I belive some SGI machines have graphics hardware supporting 10-10-10-2 R-G-B-A in 32 bits rather than the usual 8-8-8-8. The Matrox Parhelia series also has this capability. I'm not sure if it's possible to send this sort of data down a DVI-D link though. Also, judging from the forums, support for parhelia on Linux isn't great. No 3D except in the experimental drivers, and no support for SMP with 3D. I would like to buy a parhelia card because they have two DVI outputs on a reasonably priced card - but the drivers are simply far from good enough. -- Bill Gallafent. ___ XFree86 mailing list [EMAIL PROTECTED] http://XFree86.Org/mailman/listinfo/xfree86
Re: [XFree86] XFree (4.3.0) & 32b graphics ...
On Thu, 30 Oct 2003, Romain MULLER wrote: > I'm quite a noob on Linux (and so with XFree86), and I'm asking myself if it > is possible to set color depth up to 32bpp or not AFAIK there are not graphic cards with colour depth >24. > ... In fact, all my JPEG pictures that look pretty good on Windows > (32b color depth) are ugly under Linux 24b color depth Wrong gamma correction ? (man xgamma) > ... And as far as I know, the 24b color depth of my XFree may be in cause No, it isn't. > ... Any idea ? Maybe is it possible to force 32b color depth ? You can set the frame buffer at 32bpp, but the card use only the first 24 to represent colours. -- Giuliano. ___ XFree86 mailing list [EMAIL PROTECTED] http://XFree86.Org/mailman/listinfo/xfree86
