This thread about downsampling external images on the fly is a really helpful feature! Thanks, Hraban for sharing the code!
I was wondering if it was possible to downscale also raster images embedded in pdf/svg files loaded via \externalfigure? I found a ghostscript solution online (https://stackoverflow.com/questions/9497120/how-to-downsample-images-within-pdf-file) gs \ -o downsampled.pdf \ -sDEVICE=pdfwrite \ -dDownsampleColorImages=true \ -dDownsampleGrayImages=true \ -dDownsampleMonoImages=true \ -dColorImageResolution=72 \ -dGrayImageResolution=72 \ -dMonoImageResolution=72 \ -dColorImageDownsampleThreshold=1.0 \ -dGrayImageDownsampleThreshold=1.0 \ -dMonoImageDownsampleThreshold=1.0 \ input.pdf Now, I'm wondering how to adapt grph-downsample.lua to do this? I've tried: \setupexternalfigure[ resolution=\Resolution, conversion=lowres.pdf ] And added to grph-downsample.lua local function sample_down_pdf(oldname, newname, resolution) print("DOWNSAMPLE sample_down " .. oldname .. " to " .. newname) -- MkIV: -- local image = img.scan{filename = oldname} -- LMTX: local image = figures.getinfo(oldname,1) image = image.status.private local s = format("gs \ -o \"%s\" \ -sDEVICE=pdfwrite \ -dDownsampleColorImages=true \ -dDownsampleGrayImages=true \ -dDownsampleMonoImages=true \ -dColorImageResolution=%s \ -dGrayImageResolution=%s \ -dMonoImageResolution=%s \ -dColorImageDownsampleThreshold=1.0 \ -dGrayImageDownsampleThreshold=1.0 \ -dMonoImageDownsampleThreshold=1.0 \ \"%s\"", oldname, resolution, resolution, resolution, newname) print("DOWNSAMPLE Conversion: " .. s) os.execute(s) end figures.converters["pdf"]["lowres." .. "pdf"] = sample_down_pdf But I must be missing something as the code doesn't seem to be called. Any suggestions? Thanks! Ben ___________________________________________________________________________________ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / https://www.ntg.nl/mailman/listinfo/ntg-context webpage : https://www.pragma-ade.nl / http://context.aanhet.net archive : https://bitbucket.org/phg/context-mirror/commits/ wiki : https://contextgarden.net ___________________________________________________________________________________
