I was trying to use these commands in my ini file for an animation:

Preview_Start_Size = 8
Preview_End_Size = 8

It started with the size of 8, but completed the image with size of 1 - but
I want it to complete with size of 8.

Why does it do that?  What is wrong with my statements?

--
Mike

wk: mik### [at] pyxiscom  www.pyxis.com
hm: mwe### [at] sciticom  www.geocities.com/mikepweber

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In article <390ee6a0@news.povray.org> , "Mike Weber" <mik### [at] pyxiscom>
wrote:

> I was trying to use these commands in my ini file for an animation:
>
> Preview_Start_Size = 8
> Preview_End_Size = 8
>
> It started with the size of 8, but completed the image with size of 1 - but
> I want it to complete with size of 8.
>
> Why does it do that?  What is wrong with my statements?

Nothing, this is exactly how it works. It is _preview_ only as clearly
explained in the documentation. If you set the end size smaller, it will
first generate previews down to that resolution and the switch to the final
step with full resolution.

If you want it to end with 8, just divide the image width and height by 8,
which gives you exactly the result (preview is not needed for this). Then
scale the image to 800% in a paint program. This will have (nearly) the same
effect as preview 8.


     Thorsten

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On Tue, 02 May 2000 11:26:25 -0500, "Thorsten Froehlich"
<tho### [at] trfde> wrote:

>If you want it to end with 8, just divide the image width and height by 8,
>which gives you exactly the result (preview is not needed for this). Then
>scale the image to 800% in a paint program. This will have (nearly) the same
>effect as preview 8.

Of course, the paint program needs to be the type that doesn't
interpolate when scaling an image 8 times larger. The nicer programs
interpolate by default, and often have no way to turn it off. Older
versions of simpler programs like LView Pro (windows software) will
scale an image upward without interpolation.

Hmmm, I wonder if interpolation is the correct term to use when
talking about up-sizing an image? Would the more technically correct
term actually be extrapolation? It would seem that way to me, but I
have never heard anyone refer to it like that.

Later,
Glen Berry

( Remove the "7" from 7no### [at] ezwvcom to email me. )

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According to the POV help:
The process continues until it reaches 1*1 pixels or until it reaches the
size you set with Preview_End_Size=n or +EPn. Again the value n should be a
number greater than zero that is a power of two and less than or equal to
Preview_Start_Size. If it is not a power of two, the nearest power of two
less than n is substituted. The default ending value is 1. If you set
Preview_End_Size to a value greater than 1 the mosaic passes will end before
reaching 1*1, but POV-Ray will always finish with a 1*1. For example, if you
want a single 8*8 mosaic pass before rendering the final image, set
Preview_Start_Size=8 and Preview_End_Size=8.

And that's what I did.  Now I understand - it will go from 8, then to 1,
instead of 8,4,2,1 - hmmm - too bad - that's not what I want to do.  Its for
an animation of 450 frames - and to render a very small image, then resize
it larger for 450 frames is a lot of work.  I guess letting it run overnight
is what I need to do....



--
Mike

wk: mik### [at] pyxiscom  www.pyxis.com
hm: mwe### [at] sciticom  www.geocities.com/mikepweber


"Thorsten Froehlich" <tho### [at] trfde> wrote in message
news:390f01b9$1@news.povray.org...
> In article <390ee6a0@news.povray.org> , "Mike Weber"
<mik### [at] pyxiscom>
> wrote:
>
> > I was trying to use these commands in my ini file for an animation:
> >
> > Preview_Start_Size = 8
> > Preview_End_Size = 8
> >
> > It started with the size of 8, but completed the image with size of 1 -
but
> > I want it to complete with size of 8.
> >
> > Why does it do that?  What is wrong with my statements?
>
> Nothing, this is exactly how it works. It is _preview_ only as clearly
> explained in the documentation. If you set the end size smaller, it will
> first generate previews down to that resolution and the switch to the
final
> step with full resolution.
>
> If you want it to end with 8, just divide the image width and height by 8,
> which gives you exactly the result (preview is not needed for this). Then
> scale the image to 800% in a paint program. This will have (nearly) the
same
> effect as preview 8.
>
>
>      Thorsten

Post a reply to this message

In article <390f1aa8$1@news.povray.org> , "Mike Weber" 
<mik### [at] pyxiscom> wrote:

> And that's what I did.  Now I understand - it will go from 8, then to 1,
> instead of 8,4,2,1 - hmmm - too bad - that's not what I want to do.  Its for
> an animation of 450 frames - and to render a very small image, then resize
> it larger for 450 frames is a lot of work.  I guess letting it run overnight
> is what I need to do....

Well, this is a different problem: You can try to use QuickTime Movie Player
(Pro edition) to generate an animation out of the sequence of images
automatically. You can the scale the whole movie up at once.


     Thorsten

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I use cmpeg to compose the animation from a batch file.
I see that DTA can:
(Geometrical transformation options)
    /SC[#,#[,#]]   Rescale pictures to screen res. or specified size
    /SCF[#,#[,#]]  Fast, but dumb, rescale

but how do you use that?
/SC[newx, newy]

anyone know?




--
Mike

wk: mik### [at] pyxiscom  www.pyxis.com
hm: mwe### [at] sciticom  www.geocities.com/mikepweber


"Thorsten Froehlich" <tho### [at] trfde> wrote in message
news:390f25ff@news.povray.org...
> In article <390f1aa8$1@news.povray.org> , "Mike Weber"
> <mik### [at] pyxiscom> wrote:
>
> > And that's what I did.  Now I understand - it will go from 8, then to 1,
> > instead of 8,4,2,1 - hmmm - too bad - that's not what I want to do.  Its
for
> > an animation of 450 frames - and to render a very small image, then
resize
> > it larger for 450 frames is a lot of work.  I guess letting it run
overnight
> > is what I need to do....
>
> Well, this is a different problem: You can try to use QuickTime Movie
Player
> (Pro edition) to generate an animation out of the sequence of images
> automatically. You can the scale the whole movie up at once.
>
>
>      Thorsten

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On Tue, 02 May 2000 12:42:58 -0400, Glen Berry <7no### [at] ezwvcom>
wrote:

>Hmmm, I wonder if interpolation is the correct term to use when
>talking about up-sizing an image? Would the more technically correct
>term actually be extrapolation? It would seem that way to me, but I
>have never heard anyone refer to it like that.

Interpolation it is. If you scale an image up 8 times, the only values
you know for certain are those located at pixels with coordinates
which are exactly divisible by 8. The ones in between have to be
interpolated.


Peter Popov ICQ : 15002700
Personal e-mail : pet### [at] usanet
TAG      e-mail : pet### [at] tagpovrayorg

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Uh, ignore my first reply here, I was pretty sure I knew the answer.
I know it partially anyhow.  It is like you thought for the new x and y
dimensions.  I was almost positive the third number was for color
depth.
I still have DTA on this machine so I checked on that.
I could only get the two numbers to be used meaningfully.  What the
third optional number is I couldn't say.  I managed to do a:

dta test.tga /iscaled.tga /ft /sc,8  (but not without comma)

to be without error except the saved targa wasn't anything.
Trying:

dta test.tga /iscaled.tga /ft /sc320,240,8

fails, so it appears to be neither color depth nor predefined resolution.

Bob

"Mike Weber" <mik### [at] pyxiscom> wrote in message
news:390f33ee$1@news.povray.org...
| I use cmpeg to compose the animation from a batch file.
| I see that DTA can:
| (Geometrical transformation options)
|     /SC[#,#[,#]]   Rescale pictures to screen res. or specified size
|     /SCF[#,#[,#]]  Fast, but dumb, rescale
|
| but how do you use that?
| /SC[newx, newy]
|
| anyone know?
|
|
|
|
| --
| Mike
|
| wk: mik### [at] pyxiscom  www.pyxis.com
| hm: mwe### [at] sciticom  www.geocities.com/mikepweber
|
|
| "Thorsten Froehlich" <tho### [at] trfde> wrote in message
| news:390f25ff@news.povray.org...
| > In article <390f1aa8$1@news.povray.org> , "Mike Weber"
| > <mik### [at] pyxiscom> wrote:
| >
| > > And that's what I did.  Now I understand - it will go from 8, then to 1,
| > > instead of 8,4,2,1 - hmmm - too bad - that's not what I want to do.  Its
| for
| > > an animation of 450 frames - and to render a very small image, then
| resize
| > > it larger for 450 frames is a lot of work.  I guess letting it run
| overnight
| > > is what I need to do....
| >
| > Well, this is a different problem: You can try to use QuickTime Movie
| Player
| > (Pro edition) to generate an animation out of the sequence of images
| > automatically. You can the scale the whole movie up at once.
| >
| >
| >      Thorsten
|
|

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I was trying /sc[500,500] - but that didn't work.
After reading below /sc500,500 works great!

Thanks for everyone's help!  Now I can do very small framed animations,
batch convert to resize, batch run cmpeg and I'm there!

--
Mike

wk: mik### [at] pyxiscom  www.pyxis.com
hm: mwe### [at] sciticom  www.geocities.com/mikepweber


"Bob Hughes" <per### [at] aolcom?subject=PoV-News:> wrote in message
news:390f5981@news.povray.org...
> Uh, ignore my first reply here, I was pretty sure I knew the answer.
> I know it partially anyhow.  It is like you thought for the new x and y
> dimensions.  I was almost positive the third number was for color
> depth.
> I still have DTA on this machine so I checked on that.
> I could only get the two numbers to be used meaningfully.  What the
> third optional number is I couldn't say.  I managed to do a:
>
> dta test.tga /iscaled.tga /ft /sc,8  (but not without comma)
>
> to be without error except the saved targa wasn't anything.
> Trying:
>
> dta test.tga /iscaled.tga /ft /sc320,240,8
>
> fails, so it appears to be neither color depth nor predefined resolution.
>
> Bob
>
> "Mike Weber" <mik### [at] pyxiscom> wrote in message
news:390f33ee$1@news.povray.org...
> | I use cmpeg to compose the animation from a batch file.
> | I see that DTA can:
> | (Geometrical transformation options)
> |     /SC[#,#[,#]]   Rescale pictures to screen res. or specified size
> |     /SCF[#,#[,#]]  Fast, but dumb, rescale
> |
> | but how do you use that?
> | /SC[newx, newy]
> |
> | anyone know?
> |
> |
> |
> |
> | --
> | Mike
> |
> | wk: mik### [at] pyxiscom  www.pyxis.com
> | hm: mwe### [at] sciticom  www.geocities.com/mikepweber
> |
> |
> | "Thorsten Froehlich" <tho### [at] trfde> wrote in message
> | news:390f25ff@news.povray.org...
> | > In article <390f1aa8$1@news.povray.org> , "Mike Weber"
> | > <mik### [at] pyxiscom> wrote:
> | >
> | > > And that's what I did.  Now I understand - it will go from 8, then
to 1,
> | > > instead of 8,4,2,1 - hmmm - too bad - that's not what I want to do.
Its
> | for
> | > > an animation of 450 frames - and to render a very small image, then
> | resize
> | > > it larger for 450 frames is a lot of work.  I guess letting it run
> | overnight
> | > > is what I need to do....
> | >
> | > Well, this is a different problem: You can try to use QuickTime Movie
> | Player
> | > (Pro edition) to generate an animation out of the sequence of images
> | > automatically. You can the scale the whole movie up at once.
> | >
> | >
> | >      Thorsten
> |
> |
>
>

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I think that "bilinear filtering" is also another way of saying the same
thing.

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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