Convert every other page to BW/Greyscale

[Sondzin]

I have a large number of PDF files that have several hundred pages each. I want to convert every other page in the PDF files to Greyscale.

Is there any possible way to do that?

Thanks,
David

[Lukas Engqvist]

You will have to extract pages as seperate files. Select the pages that you want to convert to greyscale and then recombine.

Alternatively make a greyscale versing extract both files into pages and interleaf.

[Sondzin]

I wouldlike to avoid extracting the pages. There are a lot of files. However, is there a way to select all odd pages or all even pages?

What do you mean by interleafing?

Thanks,
David

[Lukas Engqvist]

interleafing, selecting every secont from the greyscale.

You can do the odd pages on script but then you will need Pitstop or some other PDF editing plugg.

[eugenetyson]

You need to strip out the odd pages and the even pages and grayscale just the odds and then recombine the whole thing.

My thoughts on it.

Place the PDF into indesign, look up Zanelli's script/plugin for this PDF placer.

To be able to convert to grayscale from indesign you will have to Find all the Objects with a style of NONE and change it to an opacity of 99.9% (to force it through the transparency flattner).


File Print

Choose Grayscale option

Print only the odd pages.

Do the same thing again, but Print only the even pages in Colour.

Open both files and extract all the pages to separate files.

The files should be numbered 1, 2, 3, 4, 5, 6

In both sets of files, so at the moment it's hard to combine all the files in again. You need to renumber all the odd pages as odds and evens as just even numbers.

So using something like Unix you could do something like this

#!/bin/bash
j=1;
for i in *.pdf;
do
mv $i $j.pdf
j=$((j+2));
done

Then change it for the even numbers

Or try one of these alternative methods

http://graphicssoft.about.com/od/renamers/Batch_Rename_Picture_Files_Tools_Tips.htm

Once you have all the pages numbered evens and odds, you can simply list them by name in your file browser and then recombine the pdf using the Acrobat feature.

[eugenetyson]

Alternative ways of getting grayscales into/out of indesign

grayscale a copy of the pdf.

Then place that in indesign and then print just the odd pages,or delete all the evens by selecting them in the layout. Then export as pdf.

Do the same for the evens, but make them the coloured version.

You still need to batch rename all the pages that you extract individually. But it's easily done.

It wouldn't take long doing the process.