I have a 352 page pdf that is a scan of a black-and-white text. The file size is 60.9 MB, which seems excessively large too me. (Is it indeed?)
Is there an easy way to convert this file to a more compressed one?
Edit. Here's a little sample:
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60MB is probably OK for a greyscale scan of 350 pages. I have some 100pg color scans that clock around 30MB. If you meant it's actually black and white (and no grey) then it's definitely too big.
Preview is probably a bad tool to try to get the file size down without hurting image quality. The only tools available will resample the image to a lower resolution. What I use in a case like this is Acrobat Pro, which will let me convert the compression of the embedded scans to JPEG2000, which can save a lot of space over normal JPEG and retain quality.
A great PDF compressor is Ghostscript (
gs), which is native in most Linux distributions and easily installable for Mac OS X and Windows.
gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dNOPAUSE -dQUIET -dBATCH \ -sOutputFile=foo-compressed.pdf foo.pdf
If it is just text and no images, it is indeed quite large.
There are several ways to compress the PDF file, and one of them is a simple solution with Preview.app:
If the result is a well compressed file but the readability is negatively impacted, you can try scanning at a much higher DPI and compressing it (to get a better compromise between file size and readability) or use a third party product to do OCR on the file (PDFPen, PDFScanner, VueScan and ABBYY FineReader are just some of the several options available).
Found this online tool, it compressed my 100 MB b&w pdf to 18 MB using the medium setting, quality is still very acceptable for reading.
It may be a problem if the user has restricted bandwidth as the file has to uploaded and re-downloaded, Dropbox or Google Drive integration is also offered as an alternative but I have not tested it.