Create a PDF with custom channel level

[luciot]

Hi to all!
I would like to automate a procedure that I currently do with Photoshop but I do not know if it can be done with IM. Here is the procedure:

1) Create a new RGB image
2) Write some text, then color it
3) Select the text level, invert selection, save the selection
4) Go to the "Channels" tab, click on the new channel just creted and set it to "Flat color"
5) Set the color to "Pantone Yellow C"
6) Save the file as PDF

I hope I have explained it well.
Thanks in advance to all!

[snibgo]

ImageMagick is a raster image processor. It saves images as raster, ie a number of pixels. I suspect your Photoshop procedure saves the PDF contents as text, or at least as vectors. IM can save images as PDF, but merely by putting a PDF wrapper round the raster images.

[fmw42]

Imagemagick also does not know Pantone colors and is not interactive. If you know the rgb color equivalent to your Pantone color, then you likely can do it all, except as snibgo points out your PDF will be a raster image embedded in a vector shell. Also Imagemagick is command line based and not a GUI tool.

[luciot]

Hi guys! Thanks for your fast reply!! So... I know that IM it's just a command line program. I think it's not possible to do what I have to do, because the additional channel is just an information that it's interpretated by the printer.

I.E. :
The Pantone Yellow C channel is translated by the printer in a command (embossing print)

If I understand what you says, it's not possible to bring this information in the file, right?

Thanks in advance.

[snibgo]

No, IM can't write Pantone data to the PDF.

[luciot]

Not even if I could translate the pantone into rgb?

[snibgo]

You can colour pixels with any colour you want, if you know the RGB (or sRGB) numbers, or CMYK, or whatever.

[luciot]

But (if I understand) when I save the PDF, I will lose that information because it's rastered in the final result, right? If I open the file with Photoshop I suppose I can't see the additional channels, but only the classic R,G,B...

[snibgo]

I don't understand the question.

When you create an image with IM, it isn't "rastered in the final result". It is always a raster image (ie pixels). Pixels might have RGB channels, or CMYK, or various others. But IM can't create channels for spot colours.

[luciot]

Ok, thanks for your help! I need to found another way, but thanks a lot for your reply!