Convert PDF with exactly the same quality

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a.khalil
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Convert PDF with exactly the same quality

Post by a.khalil »

Hi Every one

I want to convert multiple pdf to one pdf but when I try

Code: Select all

convert 0001.pdf 0002.pdf -quality 100 test30.pdf
the quality is very bad . I specify that they are copies with handwriting.

Any idea ?

Thanks
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fmw42
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Re: Convert PDF with exactly the same quality

Post by fmw42 »

ImageMagick is not a very good tool for vector to vector processing. It will rasterize your PDF and then embed that into a pdf vector shell. -quality is not useful for pdf processing. You probably want to change the density and resize.

Code: Select all

convert -density 288 0001.pdf 0002.pdf test30.pdf
or

Code: Select all

convert -density 288 0001.pdf 0002.pdf -resize 25% test30.pdf
This assume you start with vector pdf files with nominal 72 dpi. So 4*72=288 and 1/4=25%

The larger the density the larger better the quality, but the bigger the filesize will be.
snibgo
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Re: Convert PDF with exactly the same quality

Post by snibgo »

A more suitable tool for that task is pdfunite, which is available for *nix, Windows (eg from Cygwin), and probably many other platforms.
snibgo's IM pages: im.snibgo.com
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