Reduce scanned PDF size by converting images to grey/black&white.
This is NOT effective for mostly color or already CCITT-Group5-encoded PDFs.
Install dependencies as listed in requirements.txt.
usage: pdfreduce.py [-h] [-j JOBS] [-J] [-q QUALITY] [-t SIZE] [-g X] [-b X]
[-s X] [-i LOW] [-I HIGH]
inputfile outputfile
Reduce size of images in PDF files.
positional arguments:
inputfile input PDF file
outputfile output PDF file
optional arguments:
-h, --help show this help message and exit
-j JOBS, --jobs JOBS Parallel job number
-J, --use-jpg Use JPEG to encode images
-q QUALITY, --quality QUALITY
JPEG quality, default 95
-t SIZE, --thumb-size SIZE
Thunbnail size for checking image type, default 128
-g X, --grey-cutoff X
Grey image threshold, unit is intensity (0-255),
default 1.0
-b X, --bw-ratio X Black&White threshold, range 0-1, default 0.92
-s X, --bw-supersample X
Rate of supersampling before converting to Black&White
images, default 1.5x
-i LOW, --low LOW Set pixels with intensity [0, x] to 0, default 10
-I HIGH, --high HIGH Set pixels with intensity [255-x, 255] to 255, default
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