phatch-dev team mailing list archive

[stani <spe.stani.be@xxxxxxxxx>]

** Changed in: phatch
       Status: Triaged => Confirmed

** Changed in: phatch
    Milestone: None => 0.2.7

** Summary changed:

- autocontrast can fail on a single black pixel
+ Autocontrast can fail on a single black pixel

-- 
Autocontrast can fail on a single black pixel
https://bugs.launchpad.net/bugs/424641
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Status in Phatch = Photo & Batch!: Confirmed

Bug description:
(02:12:36) ideasman_42: stani, did you write phatch ?
(02:15:47) stani: ideasman_42: yes, I am actually writing it
(02:16:14) ideasman_42: stani, ah, my dad was using it for a bit, but we had some trouble with the brightness contrast
(02:16:35) ideasman_42: hes making a book and needed to make a whole lot of gray scans more contrasting
(02:17:06) stani: ideasman_42: did autocontrast work?
(02:17:19) ideasman_42: the problem was there seemed to be no way to make gray tones black without 100% contrast
(02:17:36) ideasman_42: didnt try but wanted all the scans to have the same color adjustment
(02:18:25) ideasman_42: stani, we did a lot of trial and error on this
(02:18:45) ideasman_42: and Im fairly sure the way it does contrast is odd or at least different to most other apps
(02:18:53) ideasman_42: stani, what would be awesome would be simple levels
(02:19:22) ideasman_42: since we only wanted to make the greys black and leave the white alone
(02:25:06) stani: ideasman_42, send me such a picture or give a download link, i like real world test cases
(02:25:09) ideasman_42: stani, http://www.graphicall.org/ftp/ideasman42/LDB_02.png , wanted something like this http://www.graphicall.org/ftp/ideasman42/LDB_02_edit.png
(02:25:16) stani: ok
(02:26:00) ideasman_42: but in a pradictable way- the problem with auto is if you apply to every picture, a small black pixel can throw it off
(02:26:57) stani: ideasman_42: would you mind if i attach these images to a bug report?
(02:27:08) ideasman_42: stani, np
(02:27:12) stani: ideasman_42, as your fathers contact details are on it
(02:27:21) ideasman_42: nah its ifne
(02:27:23) ideasman_42: fine*
(02:27:33) ideasman_42: the books online anyway
(02:28:10) ideasman_42: stani, had to use xnview instead, good ol Motif interface :S
(02:29:44) stani: which command in xnview?
(02:30:23) ideasman_42: contrast of 20 and "Change Gammut" of 0.5
(02:30:56) stani: that should be in imagemagick
(02:31:09) mp3man4: ideasman_42: does the documentation update reflect the status in python in most recent graphical builds?  or is it being updated and changed?
(02:31:25) ideasman_42: stani, still, what do you think about levels in phatch, not as some external option?
(02:32:03) stani: ideasman_42: i think it is fine, but what do you mean as an external option?
(02:32:21) ideasman_42: stani, I meant as a built in filter thats easy to access
(02:32:23) ideasman_42: hey papo 
(02:32:45) ideasman_42: like contrast is now, if internally it uses some other method then thats fine
(02:33:09) ideasman_42: could be 2 sliders, black levels and white levels if you didnt want to make an interface like the gimp