I've uploaded three files. The first (
http://www.calcworks.net/pdf/input.pdf) is a small test file with images at 300dpi, the second (
http://www.calcworks.net/pdf/output-few.pdf) was obtained by running GhostScript on the input file with the following minimal options
gs -sDEVICE=pdfwrite -q -dBATCH -dNOPAUSE -dSAFER -dPDFX -dPDFSETTINGS=/prepress -dEmbedAllFonts=true -dSubsetFonts=false -sOutputFile=output-few.pdf -f input.pdf -c quit
and the third (
http://www.calcworks.net/pdf/output-many.pdf) was obtained by running GhostScript on the input file with the following many options
gs -sDEVICE=pdfwrite -q -r300 -dBATCH -dNOPAUSE -dSAFER -dPDFX -dPDFSETTINGS=/prepress -dEmbedAllFonts=true -dSubsetFonts=false -dJPEGQ=100 -dAutoFilterColorImages=false -dColorImageFilter=/FlateEncode -dAutoFilterGrayImages=false -dGrayImageFilter=/FlateEncode -dUseFlateCompression=true -dTextAlphaBits=4 -dGraphicsAlphaBits=4 -dMaxSubsetPct=100 -dAutoFilterMonoImages=false -dMonoImageFilter=/CCITTFaxEncode -dCompatibilityLevel=1.3 -dDownsampleColorImages=false -dDownsampleGrayImages=false -dDownsampleMonoImages=false -sOutputFile=output-many.pdf -f input.pdf -c quit
PDF Checkpoint says that output-few has images at 30dpi and that output-many has images at 72dpi. Of course, this could be a bug in PDF Checkpoint but since we couldn't find many other checkers, we decided to be cautious. If this checker gets it wrong (while getting others right), then perhaps other apps in a printer's workflow will be confused too.
Bob
