Hi Teodor, If I understand your intent correctly I find dt already handles this problem well. All I find necessary in your typical mountain/sky exposure correction example is to draw a very rough drawn mask combined with a parametric mask, probably based on lightness, to limit the exposure correction to sky or mountain as desired.
No accurate curve fitting required :-) Rgds, Rob. -----Original Message----- From: Teodor Petrov [mailto:[email protected]] Sent: 28 May 2014 23:23 To: [email protected] Subject: [Darktable-users] Automatic curve fitting for exposure masking? Hi, I'm using the masking feature a lot and I'm abusing the curve tool to apply some local exposure corrections. For some time I'm wandering that it should be possible to do some automatic curve fitting on the edge between low and high intensity and thus minimize the need for placing control points by hand. For example it should be possible to place the curve at the line where some mountains (or the sea) meat the sky. Does somebody know of a tool that can be used for the job? I've tried the edge detection filters of gimp and they are pretty successful at finding the edge between a mountain and the sky. But finishing the mask by hand is a bit tedious. If there is no ready made tool, I'd be happy if someone can suggest a paper about an algorithm or a method that can be used as a base for an implementation of such tool (or even module). My desired solution for this problem looks like: 1. the user draws a rough curve 2. then pushes a button somewhere and the tool makes the curve close to perfect, so he/she can take advantage of the high dynamic range of modern cameras in just a second. Best regards, Teodor p.s. does dt support loading a mask from a bitmap? ------------------------------------------------------------------------------ Time is money. Stop wasting it! Get your web API in 5 minutes. www.restlet.com/download http://p.sf.net/sfu/restlet _______________________________________________ Darktable-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/darktable-users This email is confidential and is intended for the addressee only. If you are not the addressee, please delete the email and do not use it in any way. Please note that any views or opinions presented in this email are solely those of the author and do not necessarily represent those of the company. NHBC reserves the right to monitor all email communications. The recipient should check this email and any attachments for the presence of viruses. The company accepts no liability for any damage caused by any virus transmitted by this email. NHBC, the National House-Building Council, is limited by guarantee in England, No 320784. Registered address: NHBC House, Davy Avenue, Knowlhill, Milton Keynes MK5 8FP. NHBC is authorised by the Prudential Regulation Authority and regulated by the Financial Conduct Authority and Prudential Regulation Authority. NHBC Building Control Services Ltd, registered by guarantee in England with Company No. 01952969. Registered address: NHBC House, Davy Avenue, Knowlhill, Milton Keynes MK5 8FP. NHBC Services Ltd registered by guarantee in England, No 03067703. Registered address: NHBC House, Davy Avenue, Knowlhill, Milton Keynes MK5 8FP. If you make a claim under a Buildmark policy your personal details will be stored and processed in accordance with the Data Protection Act. Your personal details may be passed to others involved with your claim such as the original builder, or a consultant or remedial works contractor that we may employ in connection with your claim(s) and matter ancillary to your claim(s). Other than disclosure provided for in this statement, we will not pass any data about you to any other party without your permission unless we are required to do so by law. ------------------------------------------------------------------------------ Learn Graph Databases - Download FREE O'Reilly Book "Graph Databases" is the definitive new guide to graph databases and their applications. Written by three acclaimed leaders in the field, this first edition is now available. Download your free book today! http://p.sf.net/sfu/NeoTech _______________________________________________ Darktable-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/darktable-users
