Due to various constraints and limitations, it is often necessary to make the pagesize larger than actually needed and at the same time use a CropBox to crop it to the actually intended displayed/rendered size. This leads to PDFs where the page as displayed/rendered does not sit at the origin but rather away from it (i.e. where the lower left of the CropBox sits).

Some PDF processing/output tools fail to acknowldge the position of the CropBox and instead just look at the MediaBox. It is not feasible to make all those tools behave per the PDF specification, instead the new CSS property below will help by creating PDFs where the CropBox sits at the origin 0/0. The MediaBox would have the same value as that of the CropBox while the other boxes that are present (BleedBox, TrimBox, ArtBox) would also be adjusted accordingly (by the same delta as the CropBox).

Needless to say that when the switch is turned OFF, the MediaBox and the CropBox might not sit at the origin 0/0 on creating a PDF file.

Please keep in mind that this works even if the page size or CropBox are different from page to page.

With 'ICCPATH' path to a local ICC profile.

With 'ICCPATH' path to a local ICC profile. Profiles have to be accessible in the file system, it is e.g. not possible to derive them via http.

In order to define colors in a way that a regular Browser will be able to display a color the definitions can be combined with regular HTML/CSS color definitions as shown below.

Example that defines a background color as spot color with the name "Spot" using an alternate color in ICC based CMYK C=0% M=80% Y=80% K=0% and ISO Coated v2 as source color space. The spot color is used with a tint value of 75%.

.background-spot_orange-ICCbasedcmyk {
		background-color: orange;
		background-color: -cchip-icc-cmyk('./ISO Coated v2 (ECI).icc',
		'Orange',0.0,0.8,0.8,0.0, 0.75)
		}

Defining DeviceN color spaces is a bit more complex than using other color spaces, which comes from the fact that DeviceN in principle is a (multi-component) color space conceptually defined in two steps:

• First, one or several separation color space have to be established: often spot color colorants, but also process color colorants (one or even several None components could be possible).
• Second, these separation color space are defined in a certain order and form within the DeviceN color space
• In addition, the DeviceN color space itself also needs an alternate colorspace definition

@-cchip-devicen{
-cchip-devicen-name: "test-colorspace-name";
-cchip-components: -cchip-cmyk('Cyan'   ,1   ,0   ,0   ,0  )
                           -cchip-cmyk('Magenta',0   ,1   ,0   ,0  )
                           -cchip-cmyk('Yellow' ,0   ,0   ,1   ,0  )
                           -cchip-cmyk('Black'  ,0   ,0   ,0   ,1  )
                           -cchip-cmyk('Fifth colorant'  ,0.5 ,0.5 ,0.5 ,0  )
                           -cchip-cmyk('Sixth colorant'  ,0   ,0.5 ,0.5 ,0.2)
}

The alternates of the components can become defined in all supported spot color definitions (see chapter above).

A mixture of different alternate color spaces may become converted to CMYK-only alternate values.

Using and mixing different channels is similar to the usage of common color spaces, for example:

.devicen.c1  { background-color: -cchip-devicen('test-colorspace-name',1,0,0,0,0,0);  }
 .devicen.c2  { background-color: -cchip-devicen('test-colorspace-name',0,1,0,0,0,0);  }
    .devicen.c3  { background-color: -cchip-devicen('test-colorspace-name',0,0,0,0.25,1,0);  }

• pdfChip colors are implemented only for CSS/HTML but not for JavaScript. The following JavaScript is not possible for pdfChip colors:
• note.style.color = "rgb(155, 102, 102)"
• In some situations colors are converted to Device RGB:
  •  Rasterization.
  •  Colors are acсessed via JavaScript. E.g. if “mydiv.style.backgroundColor” in JavaScript it would be output as RGB even if it has accurately been defined as CMYK via '-cchip-cmyk' in CSS.
  •  DeviceN is not supported inside rasterized content.

*) Special value -1.0 for pdfChip-smoothness-tolerance means “nothing was set in CSS and pdfChip should use it's own default"

Example that switches overprint and overprint mode ON and sets the rendering intent to "saturation" for a color.

.background-spot_orange-ICCbasedcmyk {
    -cchip-overprint: 1;
    -cchip-overprint-mode: 1;
    -cchip-rendering-intent: absolute-colorimetric;
    background-color: orange;
    background-color: -cchip-icc-cmyk('./ISO Coated v2 (ECI).icc',
    'Orange',0.0,0.8,0.8,0.0, 0.75);
}

The CSS3 property "opacity" can be used in order to define transparent PDF objects.

E.g. style="opacity: 0.5" sets opacity to 50%, the ca value in the result PDF's Extended Graphic State is thereby set to 0.5.