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Last post Author Topic: Sagelight Image Editor - pay what you want promo (Apil 2010)  (Read 43902 times)

JavaJones

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Re: Sagelight Image Editor - pay what you want promo (Apil 2010)
« Reply #150 on: January 20, 2011, 01:31:06 PM »
Excellent, tooltips working great. Thanks for the quick fix!

- Oshyan

Rob Nelson

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Re: Sagelight Image Editor - pay what you want promo (Apil 2010)
« Reply #151 on: January 21, 2011, 11:08:21 AM »
I am not a user, but I just want to say it is awesome how supportive you are of your users. A few days back I took a bit of a gander over your website and the product, and I think that you and Sagelight are an excellent example of the way software is supposed to work. If I hear of family or friends needing a photo-touchup tool, I'll definitely give a pointer towards your product. :)

Keep up the good work.  :Thmbsup:

Thanks so much for that.  It definitely makes the hard work more worth it! 

Thanks again,

Rob

Rob Nelson

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Re: Sagelight Image Editor - pay what you want promo (Apil 2010)
« Reply #152 on: January 21, 2011, 11:21:58 AM »
Oh, good -- I'm glad the tooltips are working on XP now... Shame they don't fade in and all, but, oh well. ha.

cyberdiva:  Thanks for the note about the uninstall.

Oh, I also fixed a bug.  If you load a RAW file and see "There was an Unknown Error", this is fixed in the latest release. (it was caused by an error in the EXIF routine).  (The latest version is on the blog at http://sagelighteditor.wordpress.com)

I think a lot of people here are partial to RAW, right?  I just added an update that does a slight graduated-edge-sharpen on the C*I*E L channel, which really seems to make a difference, especially when used with the Definition Sliders (a very slight sharpen that doesn't hurt the data seems to give the Definition Sliders nice starting point "push").  You can turn it off, but I think, for most people, that's going to more of a plus (since the images just look better throughout the entire editing process).

I'm piecing together the next level of RAW functionality right now, including a staging area where you can select the demosaicing, sharpening, etc. -- and see it all happen in more-or-less realtime.  I'm curious as to what demosaicing algorithms people here prefer.  They tend to be different from camera-to-camera, and it would be nice to get some ideas on that.

Also, someone asked me a while back if there was a way for people to do their own demosaicing -- I can see it being an issue because of the different ways in which cameras put out their data.  It would be easy for me to add a .DLL interface if I thought the demand was high enough.

Your thoughts would be appreciated.

Rob


Curt

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Re: Sagelight Image Editor - pay what you want promo (Apil 2010)
« Reply #153 on: January 21, 2011, 11:44:27 AM »
-forgive my ignorance, but I had to look that one up:


Quote from: Wikipedia, on 'demosaicing'
To reconstruct a full color image from the data collected by the color filtering array, a form of interpolation is needed to fill in the blanks. The mathematics here is subject to individual implementation, and is called demosaicing.


A demosaicing algorithm is a digital image process used to reconstruct a full color image from the incomplete color samples output from an image sensor overlaid with a color filter array (CFA). Also known as CFA interpolation or color reconstruction, another common spelling is demosaicking.


Most modern digital cameras acquire images using a single image sensor overlaid with a CFA, so demosaicing is part of the processing pipeline required to render these images into a viewable format. However, a Bayer image can be also seen as a grayscale image.

Many modern digital cameras can save images in a raw format allowing the user to demosaic it using software, rather than using the camera's built-in firmware.


Goal:
The aim of a demosaicing algorithm is to reconstruct a full color image (i.e. a full set of color triples) from the spatially undersampled color channels output from the CFA. The algorithm should have the following traits:

    * Avoidance of the introduction of false color artifacts, such as chromatic aliases, zippering (abrupt unnatural changes of intensity over a number of neighboring pixels) and purple fringing
    * Maximum preservation of the image resolution
    * Low computational complexity for fast processing or efficient in-camera hardware implementation
    * Amenability to analysis for accurate noise reduction


Use in computer image processing software:
When one has access to the raw image data  from a digital camera, one can use computer software with a variety of different demosaicing algorithms instead of being limited to the one built into the camera. A few raw development programs, such as Raw Therapee, give the user an option to choose which algorithm should be used. Most programs, however, are coded to use one particular method. The differences in rendering the finest detail (and grain texture) that come from the choice of demosaicing algorithm are among the main differences between various raw developers; often photographers will prefer a particular program for aesthetic reasons related to this effect.

The color artifacts due to demosaicing provide important clues for identifying photo forgeries.

http://en.wikipedia.org/wiki/Demosaicing

excerpts

CWuestefeld

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Re: Sagelight Image Editor - pay what you want promo (Apil 2010)
« Reply #154 on: January 21, 2011, 12:25:53 PM »
Here's a good page for comparison of various demosaicing algorithms: http://www.rawtherapee.com/RAW_Compare/

From that page, it seems clear that RawTherapee's EAHD is the best, but of course these things vary from photo to photo. Unfortunately you can't just pick up the algorithm, though. In many cases they're proprietary, or perhaps even patented.

Rob, I wonder if your work on color spaces could be leveraged here. I wonder if the non-proprietary non-patented algorithms might work better when they're operating in alternate color spaces.

JavaJones

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Re: Sagelight Image Editor - pay what you want promo (Apil 2010)
« Reply #155 on: January 21, 2011, 03:15:18 PM »
I am super excited about the option to pick demosaicing algorithms. Truth be told I seldom *need* this feature, but I've had call for it often enough in the past that other editors have frustrated me for their lack of choice. I'm not going to use RAW Therapee as a pre-processor, adding yet another to my workflow, unless I absolutely have to. It's also surprising how mediocre or even bad some high-end apps' algorithms are.

I haven't looked at the results from different algorithms and apps for some time, but about a year back I dug pretty deeply into it. Unfortunately I don't recall what my favorites were or I'd make some suggestions. But I'm a big fan of options, so the more (good ones) you can put in there, the better IMO.

- Oshyan

Rob Nelson

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Re: Sagelight Image Editor - pay what you want promo (Apil 2010)
« Reply #156 on: January 21, 2011, 06:35:43 PM »
Here's a good page for comparison of various demosaicing algorithms: http://www.rawtherapee.com/RAW_Compare/

From that page, it seems clear that RawTherapee's EAHD is the best, but of course these things vary from photo to photo. Unfortunately you can't just pick up the algorithm, though. In many cases they're proprietary, or perhaps even patented.

With the Article on Raw Therapee -- I couldn't download the original source, so I can't do an independent assesement.  I not sure what the default settings were left or not.

Anyone have a link to the original RAW source (the one on the site is broken)?

I have tried as many algorithms as I can find, and find the traditional AHD to be the best overall algorithm, because it doesn't really cause this edge issue (which comes have as wierd lines or sparkling of the image is sharpened).   For example, according to the article, the EAHD algorithm seemed to do the best, but I'd like to see how it works overall with a lot of images.

I'm glad Curt posted that above, because it did make me think of a couple things.   I can see why most editors don't offer a selection of algorithms -- you really need to know a lot do that, and it ends up complicating things for people who don't look at it that seriously.  I do, for sure, but a lot of people who use Sagelight don't -- I think I am finally figuring out how to strike a balance with all that, though. I hope. ha.

Also, I wouldn't necessarily agree with one point, though -- I don't think that all editors that don't offer the choice of demosaicing algorithms necessarily use the same one.  Certain cameras identifiably don't work with certain algorithms; it's just that the editor wants to pick for you based on certain criteria.

The nice thing (with the proprietary issue) is that a lot of these algorithms are under GPL license.  So, I can just write a .DLL to use them without having to give away the source to Sagelight. :)


Quote
Rob, I wonder if your work on color spaces could be leveraged here. I wonder if the non-proprietary non-patented algorithms might work better when they're operating in alternate color spaces.

You know, I was thinking the same thing.  I can't say I am familiar with how all of these demosaicing algorithms work, but I was thinking that it would be interesting to look at it as a C*I*E LAB-interpreted image, for example -- this may be the basis for some of these algorithms that "blur" the image, the idea being that you'd construct a grayscale image from the pattern and then average (in some way or another) just the colors.

Well, it makes me excited to try it all out.

Rob


Rob Nelson

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Re: Sagelight Image Editor - pay what you want promo (Apil 2010)
« Reply #157 on: January 21, 2011, 06:39:58 PM »
Quote
I haven't looked at the results from different algorithms and apps for some time, but about a year back I dug pretty deeply into it. Unfortunately I don't recall what my favorites were or I'd make some suggestions. But I'm a big fan of options, so the more (good ones) you can put in there, the better IMO.

I can put int the standard ones pretty easily..   But, I do like the idea of looking at it myself, too, or to do some research on some of the new methods out there.

Have any RAW files you recall having trouble with (or distinct difference between the demosaic algorithms)?

Rob

JavaJones

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Re: Sagelight Image Editor - pay what you want promo (Apil 2010)
« Reply #158 on: January 21, 2011, 08:06:50 PM »
When I looked into it a year or so ago there were of course several test-case problem files provided with various test result pages, but also I found a few of my own test cases. I can see if I can dig them up now, but I honestly am not sure where they are...

I have a long-term web project in my mind to setup a site that would be explicitly designed to allow sophisticated comparison of these types of things...

- Oshyan