colorizing

colorizing

[Henning Hraban Ramm]

Ahoi!

Is it possible to "colorize" bitmap or greyscale images with ConTeXt?

e.g. I use a bitmap logo that should show exactly the same color as defined 
for backgrounds. If I define the "same" color with PhotoShop it looks 
slightly different. Further I'd like to place it white on color.

I know that at least PDF 1.4 enables such with "DeviceN" colorspaces,
but I found no way to do it with ConTeXt.
It should as easy as in other functions to assign foreground and background 
color, maybe even transparency?

Grüßlis vom Hraban!

Re: colorizing

[Hans Hagen]

At 06:17 PM 1/28/2002 +0100, Henning Hraban Ramm wrote:

>Is it possible to "colorize" bitmap or greyscale images with ConTeXt?

no

>e.g. I use a bitmap logo that should show exactly the same color as defined
>for backgrounds. If I define the "same" color with PhotoShop it looks

ah, so it's tuned for some kind of paper

>slightly different. Further I'd like to place it white on color.
>
>I know that at least PDF 1.4 enables such with "DeviceN" colorspaces,
>but I found no way to do it with ConTeXt.

many features of pdf can be applied (for instance, here i have a 
rudimentary system for outline fonts, but i still need to adapt the color 
driver for independent stroke and fill colors at the user level, some day 
...; btw: quite funny to be able to search for invisible text).

>It should as easy as in other functions to assign foreground and background
>color, maybe even transparency?

when i browsed the specs some time ago i got the impression that this is 
doable, but so far i didn't need it (although i will probably need it 
soon). Building ther sources is trivial (once i understand it) and we can 
probably hook things into the resource dict of graphics, but cooking up a 
proper interface will take me some time. We can look into the specs at the 
coming dante meeting to see what can be done.

Hans
-------------------------------------------------------------------------
                                   Hans Hagen | PRAGMA ADE | pragma@wxs.nl
                       Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
  tel: +31 (0)38 477 53 69 | fax: +31 (0)38 477 53 74 | www.pragma-ade.com
-------------------------------------------------------------------------
                                   fall-back web server: 
www.pragma-pod.nl
-------------------------------------------------------------------------

Re: colorizing

[Henning Hraban Ramm]

Am Dienstag, 29. Januar 2002 21:01 schrieb Hans Hagen:
> >e.g. I use a bitmap logo that should show exactly the same color as
> > defined for backgrounds. If I define the "same" color with PhotoShop it
> > looks
> ah, so it's tuned for some kind of paper

I switched off all color management and used absolute measures.

I "solved" the problem with a clip path. And I was surprised that Photoshop 6 
isn't able to write a spot color bitmap as PDF -- I know such is possible, at 
least with PDF 1.4 -- another disappointment by Adobe.

> ...; btw: quite funny to be able to search for invisible text).
That feature is for scanned documents with OCR'ed text. Some firms or boards 
use PDF to archive their documents...

> >It should as easy as in other functions to assign foreground and
> > background color, maybe even transparency?
>
> when i browsed the specs some time ago i got the impression that this is
> doable, but so far i didn't need it (although i will probably need it
> soon). Building ther sources is trivial (once i understand it) and we can
> probably hook things into the resource dict of graphics, but cooking up a
> proper interface will take me some time. We can look into the specs at the
> coming dante meeting to see what can be done.

Uäh, specs... ;-(
;-)

Grüßlis vom Hraban!

Re: colorizing

[Hans Hagen]

At 07:44 PM 2/2/2002 +0100, Henning Hraban Ramm wrote:
>Am Dienstag, 29. Januar 2002 21:01 schrieb Hans Hagen:
> > >e.g. I use a bitmap logo that should show exactly the same color as
> > > defined for backgrounds. If I define the "same" color with PhotoShop it
> > > looks
> > ah, so it's tuned for some kind of paper
>
>I switched off all color management and used absolute measures.
>
>I "solved" the problem with a clip path. And I was surprised that Photoshop 6
>isn't able to write a spot color bitmap as PDF -- I know such is possible, at
>least with PDF 1.4 -- another disappointment by Adobe.

Just curious: how well is photoshop pdf today? It used to be non valid pdf 
for viewers ...

Also: watch out when saving-as-pdf in illustrator (actually pdf is kind of 
the native illustrator format since v 9): you get everything twice: once as 
edit stream (moved some 7000 points in the margin) and as preview (as well 
as a bunch of ps code in a stream). Saving ai files in minimal pdf with 
proper boundingbox was discussed recently with adobe (tex-adobe meeting a 
couple of weeks ago).

> > ...; btw: quite funny to be able to search for invisible text).
>That feature is for scanned documents with OCR'ed text. Some firms or boards
>use PDF to archive their documents...

also, that text stream goes into a separate page stream (a page can have 
multiple streams).

> > >It should as easy as in other functions to assign foreground and
> > > background color, maybe even transparency?
> >
> > when i browsed the specs some time ago i got the impression that this is
> > doable, but so far i didn't need it (although i will probably need it
> > soon). Building ther sources is trivial (once i understand it) and we can
> > probably hook things into the resource dict of graphics, but cooking up a
> > proper interface will take me some time. We can look into the specs at the
> > coming dante meeting to see what can be done.
>
>Uäh, specs... ;-(
>;-)

right, s p e c s

Hans
-------------------------------------------------------------------------
                                   Hans Hagen | PRAGMA ADE | pragma@wxs.nl
                       Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
  tel: +31 (0)38 477 53 69 | fax: +31 (0)38 477 53 74 | www.pragma-ade.com
-------------------------------------------------------------------------
                                   fall-back web server: 
www.pragma-pod.nl
-------------------------------------------------------------------------

Re: colorizing specs

[Henning Hraban Ramm]

Am Sonntag, 3. Februar 2002 19:22 schrieb Hans Hagen:
> Just curious: how well is photoshop pdf today? It used to be non valid pdf
> for viewers ...

When?
I use Photoshop PDF since my first ConTeXt project (you remember: that 
book...) without problems. (I had Photoshop 4.01 that time, as far as i can 
remember.)

> Also: watch out when saving-as-pdf in illustrator (actually pdf is kind of
> the native illustrator format since v 9): you get everything twice: once as

Actually they build PDF 1.0 after the AI file format...

> as a bunch of ps code in a stream). Saving ai files in minimal pdf with
> proper boundingbox was discussed recently with adobe (tex-adobe meeting a
> couple of weeks ago).

Yes, in the "PostScript & PDF Bibel" they recommend the old PS->Distiller way 
for Illustrator. (With certain exceptions.)

> > > cooking up a proper interface will take me some time. We can look into
> > > the specs at the coming dante meeting to see what can be done.
> >Uäh, specs... ;-(
> >;-)
> right, s p e c s

BTW: I look normally with specs. 8-)
I don't know into whose specs you want to look? (Look into my specs, babe...?)

Grütze für alle! (Greasings to all!)

Re: colorizing specs

[Hans Hagen]

At 08:19 PM 2/4/2002 +0100, Henning Hraban Ramm wrote:
>Am Sonntag, 3. Februar 2002 19:22 schrieb Hans Hagen:
> > Just curious: how well is photoshop pdf today? It used to be non valid pdf
> > for viewers ...
>
>When?

4.0

>I use Photoshop PDF since my first ConTeXt project (you remember: that
>book...) without problems. (I had Photoshop 4.01 that time, as far as i can
>remember.)

ah, so .01 is better, probably too late to update [i just use png these days]

> > Also: watch out when saving-as-pdf in illustrator (actually pdf is kind of
> > the native illustrator format since v 9): you get everything twice: once as
>
>Actually they build PDF 1.0 after the AI file format...

right (although i wonder if ai had objects), and now its reversing

> > > > cooking up a proper interface will take me some time. We can look into
> > > > the specs at the coming dante meeting to see what can be done.
> > >Uäh, specs... ;-(
> > >;-)
> > right, s p e c s
>
>BTW: I look normally with specs. 8-)
>I don't know into whose specs you want to look? (Look into my specs, babe...?)

right, you got it: you're are going to write the "extensive bitmap 
manipulations specs", so that at the dante meeting we have something to 
talk about

Hans

-------------------------------------------------------------------------
                                   Hans Hagen | PRAGMA ADE | pragma@wxs.nl
                       Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
  tel: +31 (0)38 477 53 69 | fax: +31 (0)38 477 53 74 | www.pragma-ade.com
-------------------------------------------------------------------------
                                   fall-back web server: 
www.pragma-pod.nl
-------------------------------------------------------------------------

Re: colorizing specs

[Henning Hraban Ramm]

Am Dienstag, 5. Februar 2002 09:39 schrieb Hans Hagen:
> >Actually they built PDF 1.0 after the AI file format...
> right (although i wonder if ai had objects), and now its reversing

More precise: They built the *page descriptions* of PDF after the AI format,
that is, only the commands for vector elements, text and small raster images.
In PDF these are embedded in objects, in AI they're not.

> right, you got it: you're are going to write the "extensive bitmap
> manipulations specs", so that at the dante meeting we have something to
> talk about

I must write my tutorial first, and a handout until next weekend (you got the 
mail, didn't you). And by the way I should prepare our wedding ceremony and 
another volume of a magazine. And there's a bit of work I must do to get paid 
for...
And I think we've enough other stuff to talk about at DANTE. ;-)

Grütze für alle!