very different results in Imagemagick 6.7.8-9 vs 7.0.8-53 and confused about fuzz option

Post any defects you find in the released or beta versions of the ImageMagick software here. Include the ImageMagick version, OS, and any command-line required to reproduce the problem. Got a patch for a bug? Post it here.
Post Reply
adrianTNT
Posts: 1
Joined: 2019-07-15T07:37:38-07:00
Authentication code: 1152

very different results in Imagemagick 6.7.8-9 vs 7.0.8-53 and confused about fuzz option

Post by adrianTNT » 2019-07-15T07:45:32-07:00

I have this image kindle.jpg, while trying to simplify the image for better OCR results, I noticed that it gives different results in version 6.7.8-9 2019-02-01 vs latest version 7.0.8-53

The same command I am trying on both results below is:

Code: Select all

convert ocr_test/kindle.jpg -fill white -colorspace gray -threshold 20% temp/test.jpg
Also with both versions I see no difference if I specify -fuzz 5% or -fuzz 90%
is this a bug ?

original:
Image

converted with 6.7.8-9 2019-02-01
Image

converted with 7.0.8-53
Image

snibgo
Posts: 12429
Joined: 2010-01-23T23:01:33-07:00
Authentication code: 1151
Location: England, UK

Re: very different results in Imagemagick 6.7.8-9 vs 7.0.8-53 and confused about fuzz option

Post by snibgo » 2019-07-15T08:22:34-07:00

V6.7.8 is very very old, and had some peculiarities.

"-fuzz" is a setting that affects the behaviour of some operations (eg "-opaque"), but you don't use any of those operations.
snibgo's IM pages: im.snibgo.com

Post Reply