Harald,
I use ImageMagick/GraphicsMagick to resample HUGE high resolution tiff
images to something more manageable to work with. Using a script, I
converted hundreds of images to lower resolution copies. Then it was
simply a question of pointing ConTeXt to use the appropriate directory
to find the right figures.
The basic comand is
convert -resample 300x300
(or 100x100) and you can play with "-quality 75%"
This can be done once and is much better than getting ConTeXt to
convert every time on the fly.
Alan
On Mon, 9 Mar 2015 22:12:24 +0100
Harald Koenig
Hi,
so here's my very generic question #1 for my India book:
is it possible that context (lua?) will "shrink" all \externalfigure jpegs automatically to some specified dpi resolution and quality (e.g. 300 dpi with 95% jpeg 'quality' for print and 100 dpi and 75% for screen quality) ?
since I'm only using Linux, using Acrobat unfortueately is not an option (thanks, Adobe:-(
that book will be ~100 A4 pages with ~50% and 50% pictures, trying to have 2 pictures per page with text flowing around.
the pictures are JPG photos with quite high resolution, upto 24 Mpixel. so those picutres are HUGE and horrible overkill for a final print on A4 with typical images withs around 0.5\textwith.
I know about ghostscript being able to convert/shrink PDFs, but first the "original" PDF with full size JPGs with be really huge, and ghostscript takes ages to shrink them. so that's not real fun doing this too often...
right now I write the real typeset size of all images to the log file and use some external script to calculate the current resolution and then create a new set of images which e.g. 300 dpi.
but that's still an ugly hack still has some issues with EXIF data, rotation, clipping, ... and right now leads to strage problems (see mext mail;)
any hints to read the original large JPGs, but only write "print quality" 300dpi images, or low quaity 75dpi images for speed (and saving net bandwidth when mailing PDFs to co-workers of the group)?
thanks,
Harald