I don't have much knowledge about the jpeg format so I guess you have to
experiment a bit.
Checking for the APPE marker in the JpegImage class is a godd start. The
APPE marker are described in adobe technote 5116:

http://partners.adobe.com/asn/developer/pdfs/tn/5116.DCT_Filter.pdf

This is a good read anyway because it describes the DCTFilter.

Maybe you have to play with the ColorTransform parameter to the DCTDecode
filter?
(the DCTDecode filter is also described in some degree in the pdf spec).


Good luck :)

Tore


> -----Original Message-----
> From: Thomas Kübler [mailto:[EMAIL PROTECTED]]
> Sent: Wednesday, November 21, 2001 10:42
> To: [EMAIL PROTECTED]
> Subject: Re: Support for ICC profiles and CMYK jpeg
>
>
> hallo Tore,
>
> i have tested the image with inverted and not, but i can see
> the result in photoshop and i have to invert the image. The problem
> is, that this image looks in photoshop very good, but when the same
> pictures is in fop, the colors are different. so for example if you
> have in the pictures a white background, you can messured in photoshop
> for the colors 0%cy,0%mag,0%ye,0% bl, and in the pdf -file, generated
> with fop i have 100% cy, 47,5% mag,100% ye, 0% black and this is
> a very bad green. When i save the pictures first with photoshop and
> generated
> then the pdf, it is ok. So what happend by the save-process with photoshop
> with the pictures. One thing is the different colorspace-number, in
> java-jpeg
> the cmyk-images have the colorspace-nr: 4 and in photoshop the number 7.
> but it make no change when i save the jpeg with the number 7, so
> there must
> something else.
>
> thanks.
> thomas kübler
>
>
> ----- Original Message -----
> From: "Tore Engvig" <[EMAIL PROTECTED]>
> To: <[EMAIL PROTECTED]>
> Sent: Tuesday, November 20, 2001 10:26 AM
> Subject: RE: Support for ICC profiles and CMYK jpeg
>
>
> >
> >
> > > -----Original Message-----
> > > From: Thomas [mailto:[EMAIL PROTECTED]]
> > > Sent: Saturday, January 18, 1997 20:47
> > > To: [EMAIL PROTECTED]
> > > Subject: Re: Support for ICC profiles and CMYK jpeg
> > >
> >
> > [SNIP]
> > >
> > > hallo,
> > >
> > > i have added your support to fop, and it works for cmyk-pictures from
> > > photoshop. when i convert with jai-classes a rgb to cmyk it looks
> > > very good in photoshop, but very bad in fop. perhaps you know
> > > what i have to change in the code. i think it must be on the
> jpeg-files,
> > > perhaps i have to generated a numbering for the colors, but i
> don't know
> > > where.
> >
> > I guess the bad image you see is inverted. This is the relevant code in
> > org.apache.fop.pdf.PDFXObject (around line 193):
> >
> >   /* PhotoShop generates CMYK values that's inverse,
> >      this will invert the values - too bad if it's not a PhotoShop
> > image...*/
> >   if (fopimage.getColorSpace().getColorSpace() ==
> ColorSpace.DEVICE_CMYK)
> {
> > p = p + "/Decode [ 1.0 0.0 1.0 0.0 1.0 0.0 1.1 0.0 ]\n";
> >   }
> >
> > The decode matrix will invert the jpeg. If you comment it out, it won't
> > invert the picture, but then cmyk jpegs you save from photoshop will be
> > inverted.
> >
> > I guess there is some obvious information in the jpeg file that
> indicates
> if
> > the file is inverted or not. If anyone know where/how to find that
> > information I would gladly add code to handle it.
> >
> >
> > Tore
> >
> >
> > >
> > > thanks.
> > >
> > > thomas kübler
> > >
> > >
> > > ---------------------------------------------------------------------
> > > To unsubscribe, e-mail: [EMAIL PROTECTED]
> > > For additional commands, email: [EMAIL PROTECTED]
> > >
> > >
> >
> >
> > ---------------------------------------------------------------------
> > To unsubscribe, e-mail: [EMAIL PROTECTED]
> > For additional commands, email: [EMAIL PROTECTED]
> >
>
>
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>


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