pdftocairo -paper crop

       -paper size
              Set  the  paper  size to one of "letter", "legal", "A4", or "A3" (PS,PDF,SVG only).  This can also be set to "match", which will set
              the paper size of each page to match the size specified in the PDF file. If none the -paper, -paperw, or -paperh options are  speci‐
              fied the default is to match the paper size.

I suggest to add a crop value to the pdftocairo -paper option to mean the crop area dimensions, specified by the -W and -H options.

Edited Jul 26, 2019 by vstepaniuk

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