Howto reduce PDF file size from command line

# gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/screen -dNOPAUSE -dQUIET -dBATCH -sOutputFile=output.pdf input.pdf

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Linux: Convert PDF to image

Using "convert" command.

Examples:

• convert -quality 100 -density 600x600 multipage.pdf single%d.jpg
• convert -geometry 1600x1600 -density 200x200 -quality 100 file.pdf file.jpg