Here is part of the manual for
pdfimages, part of the
XPDF suite:
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pdfimages(1) pdfimages(1)
NAME
pdfimages - Portable Document Format (PDF) image extractor (version
3.02)
SYNOPSIS
pdfimages [options] PDF-file image-root
DESCRIPTION
Pdfimages saves images from a Portable Document Format (PDF) file as
Portable Pixmap (PPM), Portable Bitmap (PBM), or JPEG files.
Pdfimages reads the PDF file, scans one or more pages, PDF-file, and
writes one PPM, PBM, or JPEG file for each image, image-root-nnn.xxx,
where nnn is the image number and xxx is the image type (.ppm, .pbm,
.jpg).
NB: pdfimages extracts the raw image data from the PDF file, without
performing any additional transforms. Any rotation, clipping, color
inversion, etc. done by the PDF content stream is ignored.
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