Thorsten Froehlich wrote:
> 
>>  Then every existing image format is lossy because POV-Ray calculates
>>the color components as 32-bit floats. Converting them eg. to
>>8 bits-per-component or even 16 bits-per-component image (eg. PNG)
>>is lossy.
> 
> I would not be surprised if floating-point colors were part of some TIFF
> format specification ;-)
> 
     Or maybe FITS standard for astronomical pictures ?

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Christopher James Huff <cja### [at] earthlinknet> wrote:
> They do so with less precision, but 32 bits per component 
> is overkill for most things.

  Not if you want to perform post-processing of POV-Ray images... :)

  (And btw, wouldn't them be useful for HDRI images?)

-- 
#macro N(D)#if(D>99)cylinder{M()#local D=div(D,104);M().5,2pigment{rgb M()}}
N(D)#end#end#macro M()<mod(D,13)-6mod(div(D,13)8)-3,10>#end blob{
N(11117333955)N(4254934330)N(3900569407)N(7382340)N(3358)N(970)}//  - Warp -

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Thorsten Froehlich wrote:
> A ping is not a reliable way to check network reliability. 
that may be true, but the network can't be stable if even a ping can't 
get through for a lot of the time...

> Some of those noname cards cannot keep a network up even if they sit next to
> each other!  With brand name hardware it will work just fine and signals
> pass at least through two 18 cm reinforced concrete floors and three 25 cm
> brick walls (my home setup).  Or work 70 m away from your home.  At least
> they did for me in the past four years.  And in many different locations and
> setups it also works reliably.  You really need reliable hardware, that is
> all ;-)
i think d-link isn't such a noname brand ;) and there shouldn't be any 
incompatibilities between products of one brand which were designed to 
be used together, as the whole wlan-network is based on d-link hardware.
the only thing i can think of as a roblem, except for the walls would be 
  the OS used on the server machine. currently i'm using win2k pro sp4, 
but it may be too hard for windoze to handle 3 network interfaces at the 
same time (1 wlan, 1 lan, 1 internet) i really would like to use linux 
for server purposes, but i'm not familiar enough with it to ensure 100% 
uptime, and as my father uses the server for his company, this is not 
acceptable :( (he has no problems BTW with the network, as he is 
connected via lan...)

bye,
     Marc

---------------------------------
and god said: let there be a light_source { location SUN look_at EARTH, 
rgb SUNLIGHT }

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In article <4035ebdb@news.povray.org>, Warp <war### [at] tagpovrayorg> 
wrote:

> Christopher James Huff <cja### [at] earthlinknet> wrote:
> > They do so with less precision, but 32 bits per component 
> > is overkill for most things.
> 
>   Not if you want to perform post-processing of POV-Ray images... :)
> 
>   (And btw, wouldn't them be useful for HDRI images?)

Depends...most processing is unlikely to benefit much from the greater 
precision, and it uses more memory. ILM uses a half-precision 16 bit 
format...a sign bit, a 5-bit exponent, and 10 bit mantissa.

Hmm...there's nothing stopping you from putting those half-precision 
float values in a 48-bit PNG image, though they won't display properly 
in any PNG reader. FNG? Even has a nice pronunciation: FaNG

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: <chr### [at] tagpovrayorg>
http://tag.povray.org/

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In article <40355f97$1@news.povray.org>,
 "Tim Nikias v2.0" <tim.nikias (@) nolights.de> wrote:

> Well, for one, I can use BMP directly as wallpaper on my Windows OS.

And as I recall, Windows only accepts BMP files for this, right? 
Stupid...Mac OS allows anything QuickTime can open: JPEG, PNG, GIF, 
TIFF, etc.


> I don't
> need more than the 24bit it comes with, that's another. And, most of the
> time, the image gets converted to JPG anyway, either for posting on these
> very newsgroups that I've got open and running almost every hour my PC is
> running, or for my website. Only seldomly do I need other formats, like for
> a book publishing. And even then, 24bit was sufficient so far.

But the smaller file size isn't a benefit?


> But I've never really understood that gamma issue with PNGs... How exactly
> does it work, and how is it supposed to work? I've heard that it stores the
> gamma value it has been made with, and a viewing app would adjust the gamma
> to compensate for different screens, but does it really work?

That's what it does, and it does work...if the software displaying the 
PNG handles the gamma value. I don't know how common that is...

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: <chr### [at] tagpovrayorg>
http://tag.povray.org/

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> And as I recall, Windows only accepts BMP files for this, right?
> Stupid...Mac OS allows anything QuickTime can open: JPEG, PNG, GIF,
> TIFF, etc.


Windows XP supports BMP, GIF, JPEG, PNG and DIB (?) for background images.

 - Slime
 [ http://www.slimeland.com/ ]

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In article <40362ee6$1@news.povray.org> , Marc Roth <mar### [at] rothconsultcom>
wrote:

> i think d-link isn't such a noname brand ;)

Indeed, they should work.  Of course, you are out of luck if somebody else
nearby is using noname hardware...

> currently i'm using win2k pro sp4

If you get a chance, try XP.  It might work better as it came out after
WLANs were popular, rather than before.

Alternatively, I would strongly recommend use a real WLAN router.  Those
routers (for around US$ 100 you get really good and feature-rich ones these
days) usually have a few ethernet connectors, a WLAN interface and an
ethernet interface for the external network connection (i.e. a DSL or cable
modem, some even include a modem or ISDN interface or at least a serial
port).  And these routers can be configured via a web browser from the
inside of the network easily.

Even more important, you can hide the Windows system behind a firewall and
only expose selected ports (i.e. if you run a web server on the Windows
system you would only expose port 80).  Especially a Windows box connected
directly to the internet is a problem these days with all the viruses
floating around.  Even more so if you also store important or private data
on the Windows system!

As far as using Linux is concerned, a server exposed to the internet indeed
requires a good understanding of Linux to really configure right.  So a
router is probably the better choice.  And a router also does not go offline
if the Windows system crashes.

    Thorsten

____________________________________________________
Thorsten Froehlich, Duisburg, Germany
e-mail: tho### [at] trfde

Visit POV-Ray on the web: http://mac.povray.org

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> No. You just have to turn on "active desktop", after which Windows will
> accept as background anything IE can display, including web pages
> dynamically refreshed.

But who would want to use Windows IE for wallpaper reasons with all the
security leaks..? That aside, Active Desktop threw up on me several times.
So I just use BMP.

-- 
"Tim Nikias v2.0"
Homepage: <http://www.nolights.de>
Email: tim.nikias (@) nolights.de

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> Windows XP supports BMP, GIF, JPEG, PNG and DIB (?) for background images.

Windows 2000 is running here. Don't like XP. Mainly because the newer the
Windows version, the higher the hardware it requires to run as smoothly as
the predecessor running the same apps...

-- 
"Tim Nikias v2.0"
Homepage: <http://www.nolights.de>
Email: tim.nikias (@) nolights.de

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> And as I recall, Windows only accepts BMP files for this, right?
> Stupid...Mac OS allows anything QuickTime can open: JPEG, PNG, GIF,
> TIFF, etc.

Yup. I know, it sucks. Linux accepts all kinds of images as well, which is
kinda fun, especially with neato effects. :-) But most of my software
requires Windows, and I'm not yet that much into Linux as if I could switch.

> But the smaller file size isn't a benefit?

It would be, if it'd be needed. I've got several GBs to spare, so rendering
at BMP isn't a threat. Additionally, I do almost no post-processing on my
images, so I can just keep the source-code. Most of my images render in
under a few hours, so that's sufficient. Those that don't... Well, just a
little more patience required. That aside, I regularly update my hardware,
so after a year or so, images render even faster than initially. In a sense,
I don't have to keep as many images as I do, and for lazy reasons I keep
them in BMP to use them as wallpapers.

There are good arguments to use a different format, I don't deny that. It's
just much easier this way in my current PC situation. Why go through the
hassle of converting images everytime I want a new wallpaper? It's that
simple. :-)

That all aside: is the PNG compression Povray uses the optimum? I've found
that I could use Paint Shop Pro to convert the images to even smaller PNG
images and didn't notice any loss. Maybe I should experiment again and see
why PSP was able to reduce the size, but perhaps there's an issue with
output from POV-Ray to disk that can't be overcome that easily? I've got no
clue how the PNG-specs are, so maybe POV could save space if it would save
the PNG once it knows how the image looks like, but this isn't done for
buffering reasons etc. Just curious.

> That's what it does, and it does work...if the software displaying the
> PNG handles the gamma value. I don't know how common that is...

Me neither, that why I was asking. I wouldn't notice any difference on my
own PC of course, and the PC's I normally have access to are much like my
own (Screenwise), so I wasn't able to check on that yet, and also wasn't
required to work around such an issue. But we all know of the "too dark"
comments on binaries.images... I rarely do dark images, so I've had that
problem only once or twice here.

Regards,
Tim

-- 
"Tim Nikias v2.0"
Homepage: <http://www.nolights.de>
Email: tim.nikias (@) nolights.de

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