[Gimp-user] Photos negatives scanned into the gimp
Hi, I just took some photos negatives (memories from the pre-digital days :-) and put them on my flat bed scanner. So now I have a color image of these negatives in the gimp, so how do I go about turning them into a positive ? I would expect this to be a very simple operation, like a subtraction, on each pixel, right ? does this exist ? is there a tool/filter that does this ? Or do I need to code a plugin, and if so, what exactly is the operation to be done (in terms of RGB) ? Thanks, Joao -- Joao Moreira de Sa Coutinho [EMAIL PROTECTED] ___ Gimp-user mailing list Gimp-user@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-user
Re: [Gimp-user] Photos negatives scanned into the gimp
Hi, unfortunately it is not that easy, because not only have you to invert the colors, but to subtract the brown color from the film strip also. I'm not sure, but my first guess would be that this is not easily done in GIMP. Greetings, lexA Am 17.04.2007 um 22:02 schrieb Joao Moreira: Hi, I just took some photos negatives (memories from the pre-digital days :-) and put them on my flat bed scanner. So now I have a color image of these negatives in the gimp, so how do I go about turning them into a positive ? I would expect this to be a very simple operation, like a subtraction, on each pixel, right ? does this exist ? is there a tool/filter that does this ? Or do I need to code a plugin, and if so, what exactly is the operation to be done (in terms of RGB) ? Thanks, Joao -- Joao Moreira de Sa Coutinho [EMAIL PROTECTED] ___ Gimp-user mailing list Gimp-user@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-user --- Remember: There are only two tools in life. WD-40, for when something doesn't move, and should, and Duct Tape, for when something is moving and it shouldn't. So does the universe explode if you spray duct tape with WD-40? ___ Gimp-user mailing list Gimp-user@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-user
Re: [Gimp-user] Photos negatives scanned into the gimp
Hi, On Tue, 2007-04-17 at 22:58 +0200, Axel Wernicke wrote: unfortunately it is not that easy, because not only have you to invert the colors, but to subtract the brown color from the film strip also. I'm not sure, but my first guess would be that this is not easily done in GIMP. It should be easy though to write a plug-in that does this. One just needs to figure out the right values. Perhaps there are ICC color profiles for common brands of negatives that could help with this task? Sven ___ Gimp-user mailing list Gimp-user@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-user
Re: [Gimp-user] Photos negatives scanned into the gimp
Am 17.04.2007 um 23:16 schrieb Sven Neumann: Hi, On Tue, 2007-04-17 at 22:58 +0200, Axel Wernicke wrote: unfortunately it is not that easy, because not only have you to invert the colors, but to subtract the brown color from the film strip also. I'm not sure, but my first guess would be that this is not easily done in GIMP. It should be easy though to write a plug-in that does this. One just needs to figure out the right values. Perhaps there are ICC color profiles for common brands of negatives that could help with this task? There are some papers, so there is a solution :) http://www.c-f-systems.com/PhotoMathDocs.html Just somebody needed to implement it :) And yes there is a Photoshop Plug-in already. just my 2c lexA Sven --- Remember: There are only two tools in life. WD-40, for when something doesn't move, and should, and Duct Tape, for when something is moving and it shouldn't. So does the universe explode if you spray duct tape with WD-40? ___ Gimp-user mailing list Gimp-user@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-user
Re: [Gimp-user] Photos negatives scanned into the gimp
On Tue, 17 Apr 2007 22:02:51 +0200 Joao Moreira [EMAIL PROTECTED] wrote: Hi, I just took some photos negatives (memories from the pre-digital days :-) and put them on my flat bed scanner. So now I have a color image of these negatives in the gimp, so how do I go about turning them into a positive ? I would expect this to be a very simple operation, like a subtraction, on each pixel, right ? does this exist ? is there a tool/filter that does this ? Or do I need to code a plugin, and if so, what exactly is the operation to be done (in terms of RGB) ? Image-Layers-Colors-Invert ? Owen ___ Gimp-user mailing list Gimp-user@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-user
Re: [Gimp-user] Photos negatives scanned into the gimp
On Tue, Apr 17, 2007 at 11:16:28PM +0200, Sven Neumann wrote: Hi, On Tue, 2007-04-17 at 22:58 +0200, Axel Wernicke wrote: unfortunately it is not that easy, because not only have you to invert the colors, but to subtract the brown color from the film strip also. I'm not sure, but my first guess would be that this is not easily done in GIMP. It should be easy though to write a plug-in that does this. One just needs to figure out the right values. Perhaps there are ICC color profiles for common brands of negatives that could help with this task? XSane maintains a list of known values. Actually, most scanning software (including XSane) will fix it for you if you tell it you are scanning a negative. -- Hofstadter's Law states: It always takes longer than you expect, even when you take into account Hofstadter's Law. pgpCztPfkRCIB.pgp Description: PGP signature ___ Gimp-user mailing list Gimp-user@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-user
[Gimp-user] Adjusting frame brightness and contrast using GIMP-GAP
I'm using the GIMP with the GAP plugin, and I've been using it to edit frames from a movie. (Fantastic tool btw) I would like to adjust the contrast and brightness of all the frames. Can this be done with GAP? I've looked but I can't find an option for it :( (Adjusting the frames one by one is not an option, there are too many frames for that) Thanks, Marcel Hmmm, It's either very young cheese or very old meat. ___ Gimp-user mailing list Gimp-user@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-user
Re: [Gimp-user] Adjusting frame brightness and contrast using GIMP-GAP
On Tuesday, April 17, 2007 8:38 pm, Marcel wrote: I'm using the GIMP with the GAP plugin, and I've been using it to edit frames from a movie. (Fantastic tool btw) I would like to adjust the contrast and brightness of all the frames. Can this be done with GAP? I've looked but I can't find an option for it :( (Adjusting the frames one by one is not an option, there are too many frames for that) Not directly. What you will need to do is use the Frames to image... Video menu item to get a multilayered image. Then open the Filters menu and select the Filter all layers... item. From there you will have to find plug-ins that affect contrast and brightness. -- 73, AC7ZZ http://counter.li.org/ Linux User #246504 ___ Gimp-user mailing list Gimp-user@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-user
Re: [Gimp-user] Adjusting frame brightness and contrast using GIMP-GAP - solved
Scott Bicknell wrote: On Tuesday, April 17, 2007 8:38 pm, Marcel wrote: I'm using the GIMP with the GAP plugin, and I've been using it to edit frames from a movie. (Fantastic tool btw) I would like to adjust the contrast and brightness of all the frames. Can this be done with GAP? I've looked but I can't find an option for it :( (Adjusting the frames one by one is not an option, there are too many frames for that) Not directly. What you will need to do is use the Frames to image... Video menu item to get a multilayered image. Then open the Filters menu and select the Filter all layers... item. From there you will have to find plug-ins that affect contrast and brightness. I found a solution. But not by using a filter that directly affects the contrast and brightness :\ The effect I was looking for was to turn green-screen footage of a person into high contrast blackwhite/grayscale psuedo cartoon footage. Filtering out the green screen was easy, but getting the cartoon-ish effect required fiddling with an inverted 'contrast mask' layer (set to 'grain-extract') and the 'channel-mixer' filter. (and of course the 'cartoon' filter, but that one was easy :) (If you've seen the music video for the Gnarls Barkley song 'Crazy' then you'll probably have an idea of the effect I'm trying to achieve :) Thanks for the help though, Marcel --- Trying to learn about software is like trying to nail Jello to a tree ___ Gimp-user mailing list Gimp-user@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-user
