CCITT Group 4 compression

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CCITT Group 4 compression

Post by gio91ber »

Hello everyone,

I'm using the following command to batch convert a folder full of black and white TIFF files:

Code: Select all

mogrify -format tif -path output -compress Group4 -type bilevel -monochrome *.tif
I'm starting from images that are about 44.5MB each and each compressed file is about 1.84MB. In comparison Irfanview batch convert from the same images produces files which are around 64KB.

Am I doing something wrong or is something not working very well?

Thanks in advance, and sorry for my very bad english.

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Re: CCITT Group 4 compression

Post by fmw42 »

if you remove the -monochrome, does it work better. Or move monochrome before -compress and see if that works better.

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