GNOME Bugzilla – Bug 128694
histogram UI suggestion
Last modified: 2004-12-22 21:47:04 UTC
The GIMP histogram only shows the levels for one color(value) at a time. For fixing color shifted photos ( bad white balance, or aging of color media) it's very handy to see all 4 values (rgbv) up at once so one can match up the hi/mid(gamma)/low values. The Xsane front end would be a great place to look as an example of what i'm refering to, and perhaps even some code re-use. His auto correct is also very good, and usually only needs tweaking a little in the gamma correction. thanks
Another vote for this bug. I was actually looking into the 1.3.23 source release to see how hard it would be to implement it, but I'm still not sure which histogram code is more appropriate. If you put channelwise color support into the Levels histogram controls, it would be pretty complicated to set up the GUI to allow the user to manipulate the levels. If, however, you put channelwise color support into the plain Histogram dialog, then it could summarize the current histogram status without worrying about handling complex user interactions.
Actually, I was thinking of the levels histogram controls. Xsane (at least for me) has a very nice UI that lets you overlay all the graphs for rgbv, or selectively pick which are displayed. By overlaying them, it makes color shifts obvious, and color corrections, and the controls are right there for you to tweak. I can screen shot it if you don't have a copy handy
Hi Jim, Please do attach screenshots, I don't have a scanner :) Cheers, Dave.
Dave, you don't need a scanner in order to try XSane.
Found this screenshot on the web: http://www.rocklinux-consulting.de/oss/avision/scan-histogram.jpg
Created attachment 22412 [details] histogram attachment with color shifts obvious
I wanted to add one of my scan histograms to show why having all 4 values up at once is so nice when working with old or badly shot color photos. Notice the before and after graphs, and how easy it to see how the pixel distribution is. BTW, thanks for looking at this! jim
Actually, from an astethetic point of view, the XSane histogram is ugly. It would be desirable not to copy it but to find a representation that gives the advantages of the proposed histogram view w/o making it that terrible to look at.
The alternate view is a scatter map. In use, I found the traditional looking view more useful and not really all that hard to use. Maybe we can look at this another way. Let me leave up a rgbv (selectable like the xsane one is)) scatter map or level histogram that shows changes in real time. Like another tab in the view>info window, preferably resizable to allow you to see it better. I can then use the existing color controls to make the adjustments without creating any disruptive changes in the UI.
Please update to the latest 1.3 release. It has a dockable histogram that updates in real-time. Isn't that what you suggested?
I'm running RH9 and updating to the latest release has been no easy task. fontconfig-2.2.1 foomatic-db-20031220 foomatic-db-engine-3.0-20031220 foomatic-filters-3.0-20031220 gimp-print-4.3.25 gtk+-2.2.4 libgtkhtml-2.4.0 librsvg-2.4.0 pango-1.2.5 gimp-1.3.23 I'm currently not able to get past-gimp print because of issues it's having with foomatic. I tired building gimp-1.3.23 with disable-print to get it built. In general, I really like the new UI. The undocked histogram is good, but it still only shows one of the RGBV graphs at a time. The other issue is that the new levels window only shows output in linear and not log as the histogram does. It seems you folks are trying to get closer to a more "well known" UI, but I still think xsane does this better
gimp-print-4.3 would have been the wrong version anyway. As outlined in INSTALL, you need gimp-print 4.2. All tools that use a histogram view allow to switch between logarithmic and linear view in the respective tool options. This setting is saved across sessions.
Created attachment 22739 [details] levels screenshot
Actually tried 4.2.latest and had same problems with foomatic which is why I tried 4.3.latest. OK, I found the global setting for lin. vs log (still learning the new interface, sorry). Still back to how to represent the rgbv values at the same time to do color balancing.
Bug #132480 has a link to a screenshot that shows multiple histograms in one dialog: http://www.scantips.com/dual2.html
This is basically fixed in CVS. Closing as duplicate of bug #145401 which should actually have been closed a duplicate of this one. *** This bug has been marked as a duplicate of 145401 ***