Shadow Illuminator: Comments Please

[brajovic]

Hi,

I've recently put on the web an interactive demonstration of an image processing algorithm I developed at Carnegie Mellon University. Originally the method was developed to improve robot vision by emulating some aspects of human vision (notably the adaptation taking place in the retina and the early visual cortex.)

It turns out the algorithm is also good in enhancing shadows. The technology is dubbed "Shadow Illuminator." I've seen several shadow recovery tools around, but none of them seem to produce the result that Shadow Illuminator does(e.g., sharpness of details in the shadows) . Also Shadow Illuminator is intelligent, therefore it is virtually one-click solution.

The demo site and additional information is at www.shadowilluminator.org. There you can upload example images and instantaneously receive processed results. You can also view a public gallery. (As a signed in user you can contribute to the public gallery, or just maintain your private before-and-after gallery).

Would this technology be useful to photographers, graphics designers, ... ? How does it compare to other shadow recovery tools you may be familiar with? Is this something you would like to have in your toolbox?

Comments please...

thank you,

Vladimir Brajovic

P.S. Here are the links to a few examples from the current public gallery.

http://www.shadowilluminator.org/hom...305ff4240396d4
http://www.shadowilluminator.org/hom...4fb063f52425ce
http://www.shadowilluminator.org/hom...fbf10bba3b6ffb

[brajovic]

>>><<< is not the part of the password. (I'll remove it to eliminate confusion). But this is not your problem

Do not cut and paste the password from your email. Retype it manually in the password field. I don't know why this matters, but one user told me that he had this issue and it worked after he manually retyped it.

If this doesn't work, type your email address and then click on "Forgot your password" link. This will reset your password and send you a new one. It seems you are registered correctly in the database. (I can't tell you what you password is because all passwords are encoded.)

Thank you for trying the algorithm.

I'll respond to your other questions later today after I come back from my daughters dance class. In a nutshell, Shadow Illuminator will be a PS (and compatible) plug-in that you can have on your desktop. It will be affordable.


Vladimir

[jeaniesa]

Wow, this is really a great application Vladimir!! And I've only played with the "default" settings.

I would definitely find this useful in photo restoration and retouching and would use it often! I compared the results of Photo Illuminator with some photos that I had retouched "by hand" (read - spent a couple hours on) and the results with Photo Illuminator were "almost as good" to "better", depending on the photo. For those that were "almost as good", it was definitely a better starting point to finish up with color balancing, etc.

Thanks for asking for our feedback. I think this application will have high-demand if the price is right.

Jeanie

[Andrew B.]

Hi Vladimir,

Your technology looks very impressive, and it most certainly can bring out the shadows. I think a lot of people would be happy with this ability.

As for comparing with other methods, this is very hard to do. The web interface is not suitable for quick testing of different settings. But I did do one test as follows:

I ran an action on your "before" image twice. Then I turned down the opacity on the second run slightly. Then I compared this to the result you posted on the website. Even though Shadow Illuminator made the light more even, I think most consumers would be more attracted to the result of the action (which uses the "fill gray color dodge" method).

But there is more to it than this. I had to run the action twice, then turn down one layer. This is not big deal for a photo corrector, but it was an extra step. Also, I saw more potential in your result for more tweaking. And after some quick tests I was happy to have your result to work with. So I think your method has its strong and weak points, and the strong points are strong enough to make me very interested.

Anyway, I've attached a two panel image with Shadow Illuminator on the top and "fill gray color dodge" on the bottom.

[brajovic]

Don, Jeanie, Andrew and others,

Thank you for taking time to try and test Shadow Illuminator (www.shadowilluminator.org) and for sharing your opinions. Please continue to do so. Either through this forum if its of general interest, or directly via email provided in “contact us” link on the web site.

Shadow Illuminator algorithm has been originally designed to do what our eyes do (loosely speaking). In fact, the enhanced results that Shadow Illuminator produces will often resemble what our eyes see when we take the photograph. Our photographs are not as capable as our eyes so shadows appear more dramatic in the photographs. I personally love deep shadows as artistic expression in the art and studio photography. But I don’t like when those great moments that we cannot re-shoot (e.g., event photography, photo journalism, etc.) result in less then acceptable photographs. We all deal with this. We mask, we dodge, we burn, and do what not to salvage those great shots only if it wasn’t for the inappropriate illumination we had to accept at the moment. Retouching can produce great results and amazing effects. RP community is an example of amazing technical and artistic expertise that exists out there.

As Don and others pointed out, Shadow Illuminator has a potential to be “hand’s off” automatic tool to provide a starting point for additional manual retouching. It is smart. The current version works reasonably well for wide variety of images. For some images, however, the default setting may be too high. Things will be more visible, but the photorealistic appeal of the picture may be degraded. This is exactly what Andrew, Don and Jeanie pointed out (more or less). It is the issue of tonal mapping. The more of the tonal range (from nature) we want to “squeeze” and render within the available tonal range of our displays and/or print, the more the pictures will look “flat”.

(I probably could automate Shadow Illuminator further, but I though that we really want at least one slider.)

Andrew’s comparison image (see Andrew B’s posting in this thread for the attached image file) compares what Shadow Illuminator’s default setting does on one example and what can be (quickly) done in Photoshop. This is a great comparison. Exactly the kind I was looking for. If I can do something easily and efficiently in PS, why would I bother with other tools? (Photoshop is a powerful tool, as we know. In principle anything can be done if we had time, (and talent, for some of us.)

I’ve expanded Andrew’s comparison to include two additional results (the quad comparison image is at www.shadowilluminator.org/examples/SIcompare.jpg ). One version uses the result of Shadow illuminator at its default setting (denoted by SI @ +/-0) and applies PS USM (58,42,0). The outcome does not look as “flat” anymore. In fact the tonal depth and color are very close to what can be done in PS, while still showing a bit more of the shadow details.

Another way to preserve tonal “depth” is to reduce the amount of shadow enhancement required from Shadow Illuminator. If we check the most left button at the website, thus selecting the least amount of shadow enhancement, then we get the picture labeled (SI @ -2). This looks more photorealistic and still shows sufficient amount of detail.

All this comparison illustrates is that Shadow Illuminator is “work in progress” and that with simple fixes it can work reasonably well on its own, or in a workflow people are using today.

My main goal was to provide good visibility for robot vision. The photorealistic rendition was secondary. So the current default setting may be too much for some pictures. Especially fine features and textures such as hair and carpet fibers situated in deep shadows may be over enhanced in the result. To remedy this, choose lesser amount of enhancement. (Currently you must upload the original image again, basically start over, and apply a new desired setting. You cannot re-manipulate already uploaded image. Sorry…)

The bottom line: what I am currently demonstrating on the web is a bare bones research version. It will work well on most images, but not all (as is the case with most of the tools and techniques we have at our disposal). The bare bones version doesn’t do anything to improve or change color or other things. This is because at the moment I want to isolate and demonstrate what the Shadow Illuminator does by itself. I am thinking about those additional improvements, and I may have more to show you soon.

Please continue using Shadow Illuminator and continue providing comments and suggestions. If you find a particularly bad example, where SI didn’t do as good of a job, perhaps you could share a before-and-after image by posting a link that can be generated from the web site. Likewise if you could share a particularly impressive before-and-after result, please provide a link also. Examples where the SI result was further improved with modest retouching effort may also be interesting to see.

So where are we going from here? Don wants it TODAY on his desktop, and if that is not possible, than he wants to be able to upload images larger than 1MB. OK, I will increase the file size limit for signed-in users to 1.5MB. This should be plenty for even large pixel count JPEG’s.

This tool is not meant to be a web application. (Who wants to deal with network delays with 20MB tiff’s.) But my research code is in such a state that the web is the only way for me to feature it. So for now we have to use this demo site. What we really want is a PS plug-in. I can’t do this as a PS action because the computation involved is not available within Photoshop’s built-in tools. Hopefully in the next 2 months I’ll have the plug-in.

Let’s continue evaluating, and confirm that it is worthwhile pursuing the plug-in. So far, the responses are positive.

This community rocks. Thank you for all your help. I promise from now on I won’t write "essays" like this. So don’t ask hard questions…

Best regards,

Vladimir

[Andrew B.]

brajovic said:

>(I probably could automate Shadow Illuminator further, but I though that we really want at least one slider.)

I don't see any way to avoid a slider. Some of photo adjustment has to do with personal taste, and a slider allows for that.

>Please continue using Shadow Illuminator and continue providing comments and suggestions.

Shadow enhancement is an interest of mine, and I would be interested in running more tests. But all my shadow test images are copyright by other people and I can not post them to your web site. Short of using my test images, I'd like to try a few more tests on the image I started with, but at several different Shadow Illuminator levels. Then I could compare each of those levels to other methods, see how easily they can be tweaked further, or other tests. If you could provide a link or send them, I could do these tests.

Andrew

[neilvan]

All I can say is AWESOME!

Simply amazing, so much easier than trying to use levels etc...



For those that haven't tried it yet check out this! Look at the before and after.

http://www.shadowilluminator.org/gal...60&sheight=507

[brajovic]

When posting a link to an image example at www.shadowilluminator.org, please generate the proper link from "email this photo" button from either public or private gallery. (You must be a registered user to have a private gallery.) This does not actually email anything. It pops up a window with a link that can be emailed or posted. Copy and paste that link. Do not copy and paste the URL from your browser. It won't work.

Neil, thank you for sharing your example. Would you please generate the right link and point us to it. I am glad you like it. I am still amazed with some of the results myself. When you hit the right example it's a TOTAL SCREAM.

best regards,

Vlad

P.S. This link issue may be a slight usability complication, but it provides a level of security that prevents images from being easily harvested off the server. The goal is, of course, protecting copyrighted material that may be uploaded to the site. If you do not allow your images to be included in the public gallery, or you do not generate and distribute a link to your images inviting others to view it, then your material is completely private, and is for your use only. For more info ready “terms and conditions”.

[neilvan]

Hi Vladimir,

Yes, I quickly discovered what you are talking about with the link thing. Ooops!

I am so amazed at what you have created here, it's perfect. I can't wait until you are able to create a plug-in for Photoshop. Will you notify registered users when you have the plug-in available?

Here are several links:

http://www.shadowilluminator.org/hom...3e27720c470c76

http://www.shadowilluminator.org/hom...0f40b144856288

http://www.shadowilluminator.org/hom...2c08e4c62ae94a

http://www.shadowilluminator.org/hom...4237f57465640a

I posted this example in another forum I frequent:

http://groups.msn.com/OlympusCamedia..._Message=10255

and this as well:

http://groups.msn.com/OlympusCamedia..._Message=10256

Thanks again and keep up the good work! –Neil

[brajovic]

Neil,

Thanks for sharing. Your examples are great. Originals with a good quality signal do make a difference.

I just want to let you know that I also developed a smart noise cleanup that will fix the noise that cameras naturally suffer from at low light levels (e.g., shadows). I just didn’t incorporate it in the on-line demo. I’ll do it in the next week or so and set in to some mild setting. I'll post the announcement here when it is ready so that you can test it.

Vladimir

[neilvan]

Sounds great! I'll be waiting...

Neil

[brajovic]

Shadow Illuminator demonstration at www.shadowilluminator.org now includes very slight noise removal to combat the noise in the shadows that may be otherwise objectionable after the shadow enhancement.

Vladimir

[Andrew B.]

Just thought you might be interested in a couple more tests. Attached is a two panel image. The top image was done with the demo version of a plugin from Applied Science Fiction called Digital SHO. This result is surprisingly close to the Flash Fill action I posted before, although I think the action preserved the background better.

The bottom one was done with the demo version of a plugin from Chromasoftware called Shadow Control. I might be tempted to clip the black point on this one to give it a little more snap, but I left it as it came from the filter.

And, of course, this is how I set the sliders. Someone else might do this differently.

[hizaam]

*gasp*

wow!!! I'm going to take some pictures in a dark room to test it. hehehe..