Hi,

OK, I know this isn't strictly related to the 3D world, but I was going
through Nasa's site, and I found three 22 meg jpegs, each a section of a map
of the surface of Mars. One is the red colour channel, one the green and the
third the blue. I though to myself "Ohhh! Lovely high detailed closeups of
the surface in my renderings!", so I d'l them over the course of a week.

However, I have been unable to recombine them into a final Jpeg. I have
tried using both Photoshop 5.0 and Paint Shop Pro 5, but both run out of
memory (I have 128 megs, and 2 gigs available for virtual) when I try to add
the third channel.

So my question is, does anyone know a simple windows/dos command line
program that will take however long it takes, but be less dependant on
memory for this job?

Thanks,

Equiprawn

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Maybe if you turn off Undo for the time being it will be able to handle the
merges.

Bob

"Equiprawn" <equ### [at] tinetie> wrote in message
news:38adea11@news.povray.org...
| Hi,
|
| OK, I know this isn't strictly related to the 3D world, but I was going
| through Nasa's site, and I found three 22 meg jpegs, each a section of a map
| of the surface of Mars. One is the red colour channel, one the green and the
| third the blue. I though to myself "Ohhh! Lovely high detailed closeups of
| the surface in my renderings!", so I d'l them over the course of a week.
|
| However, I have been unable to recombine them into a final Jpeg. I have
| tried using both Photoshop 5.0 and Paint Shop Pro 5, but both run out of
| memory (I have 128 megs, and 2 gigs available for virtual) when I try to add
| the third channel.
|
| So my question is, does anyone know a simple windows/dos command line
| program that will take however long it takes, but be less dependant on
| memory for this job?
|
| Thanks,
|
| Equiprawn
|
|

Post a reply to this message

Hmmm... I wonder if you could render three coincident imagemaps with
different transparencies....


"Equiprawn" <equ### [at] tinetie> wrote in message
news:38adea11@news.povray.org...
> Hi,
>
> OK, I know this isn't strictly related to the 3D world, but I was going
> through Nasa's site, and I found three 22 meg jpegs, each a section of a
map
> of the surface of Mars. One is the red colour channel, one the green and
the
> third the blue. I though to myself "Ohhh! Lovely high detailed closeups of
> the surface in my renderings!", so I d'l them over the course of a week.
>
> However, I have been unable to recombine them into a final Jpeg. I have
> tried using both Photoshop 5.0 and Paint Shop Pro 5, but both run out of
> memory (I have 128 megs, and 2 gigs available for virtual) when I try to
add
> the third channel.
>
> So my question is, does anyone know a simple windows/dos command line
> program that will take however long it takes, but be less dependant on
> memory for this job?
>
> Thanks,
>
> Equiprawn
>
>

Post a reply to this message

On Sat, 19 Feb 2000 00:55:08 -0000, "Equiprawn" <equ### [at] tinetie>
wrote:

>Hi,
>
>OK, I know this isn't strictly related to the 3D world, but I was going
>through Nasa's site, and I found three 22 meg jpegs, each a section of a map
>of the surface of Mars. One is the red colour channel, one the green and the
>third the blue.

I have two questions:

1. Where can we download these ourselves?

2. Even if you do mangage to combine these, will the file be too big
for your computer to do anything usefull with? I suppose you could
always scale them down, to make them easier to work with.

Now that I think about it, you can always open the jpeg images at 1/2,
1/4, or 1/8 size, if you have the right software. LViewPro will do
this, for example. The capability is built into the jpeg routines
written by the Independent JPEG Group. Lots of software is built
around this library. You can even download free command line tools
created by the Independent JPEG Group and use them to accomplish this.


Of course, you won't have the full resolution of the original files,
but is your computer really big enough to handle that resolution
anyway? Are you going to be creating an output image that will have
enough resolution to make full use of such an input image? Something
like creating a wall mural at over 300dpi?   :)

later,
Glen Berry

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I think the core problem is the size of the images. To do any channel
combining Paint Shop Pro and Photoshop first convert the JPEG to
a bitmap, which would be something like five times as big (over
100 MB). So you have to ask yourself- do I need that much resolution?
Probably not. Try converting to another format and then reduce the size
to about 1/3. At least that is what I'd do.
HB

Post a reply to this message

Are you loading them as channels or layers?


Equiprawn wrote:

> Hi,
>
> OK, I know this isn't strictly related to the 3D world, but I was going
> through Nasa's site, and I found three 22 meg jpegs, each a section of a map
> of the surface of Mars. One is the red colour channel, one the green and the
> third the blue. I though to myself "Ohhh! Lovely high detailed closeups of
> the surface in my renderings!", so I d'l them over the course of a week.
>
> However, I have been unable to recombine them into a final Jpeg. I have
> tried using both Photoshop 5.0 and Paint Shop Pro 5, but both run out of
> memory (I have 128 megs, and 2 gigs available for virtual) when I try to add
> the third channel.
>
> So my question is, does anyone know a simple windows/dos command line
> program that will take however long it takes, but be less dependant on
> memory for this job?
>
> Thanks,
>
> Equiprawn

Post a reply to this message

On Sat, 19 Feb 2000 00:55:08 -0000, Equiprawn wrote:
>So my question is, does anyone know a simple windows/dos command line
>program that will take however long it takes, but be less dependant on
>memory for this job?

netpbm can do it.  You'll need to convert using jpgtoppm, then use
ppmtopgm to convert to pgm format, then use rgb3toppm to combine the
channels, then finally use ppmtojpg to convert back to jpg format.

I have all of these except the two jpg programs, but you could use 
Photoshop to convert to TIFF first and use tifftopnm and pnmtotiff 
instead of the jpg versions.

If you want a copy, let me know and I'll email it to you.

-- 
These are my opinions.  I do NOT speak for the POV-Team.
The superpatch: http://www2.fwi.com/~parkerr/superpatch/
My other stuff: http://www2.fwi.com/~parkerr/traces.html

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Glen Berry <7no### [at] ezwvcom> wrote:

> 1. Where can we download these ourselves?

http://maps.jpl.nasa.gov/hires.html is where you can find them, courtesy of
David Seal's Maps of the Solar System pages, themselves part of the
excellent A Space Library.  Be warned, though, as the files really are
B-I-G.  26MB, 21MB and 17MB for the red, green and blue images respectively.

> 2. Even if you do mangage to combine these, will the file be too big
> for your computer to do anything usefull with? I suppose you could
> always scale them down, to make them easier to work with.

I've scaled them down to 25% of the original size and they're still good to
work with.

Hope this helps,
Alan.

--
mailto:ala### [at] spectoorguk
http://www.specto.org.uk/

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