pdfinfo () {
  cat <<EOF
Creator:        groff version 1.23.0.rc3.81-9e3e4
Producer:       gropdf version 1.23.0.rc3.81-9e3e4
CreationDate:   Sat Mar 25 18:43:18 2023 CDT
ModDate:        Sat Mar 25 18:43:18 2023 CDT
Tagged:         no
UserProperties: no
Suspects:       no
Form:           none
JavaScript:     no
Pages:          1
Encrypted:      no
Page size:      612 x 792 pts (letter)
Page rot:       0
File size:      106745 bytes
Optimized:      no
PDF version:    1.4
EOF
}

pdfinfo \
| tr -d '\000' \
| sed -n -e '/Page *size:/s/Page * size: *\([0-9.]*\) *x * \([0-9.]*\).*$/\.nr pdfpic*width (p;\1)\
.nr pdpic*height (p;\2)/;tprint
b
:print
p'

#.  \" Get image dimensions.  The `tr` command to strip null bytes is
#.  \" distasteful, but its necessity is imposed on us.  See
#.  \" <https://gitlab.freedesktop.org/poppler/poppler/-/issues/776>.
#.  ec @
#.  sy pdfinfo @$1 | \
#tr -d '\000' | \
#sed -n -e '/Page *size:/s/Page * size: *\([0-9.]*\) *x * \([0-9.]*\).*$/\
#.nr pdfpic*width (p;\1)\
#.nr pdpic*height (p;\2)/;tprint\
#b\
#:print\
#p'\
#> @*[pdfpic*temporary-file]
#.  ec