Search found 109 matches

by rnbc
2011-09-13T17:28:43-07:00
Forum: Users
Topic: Finding isolated pixels.
Replies: 14
Views: 24971

Re: Finding isolated pixels.

With only 2 arguments I get the expected results. Not so with more... so there is a problem somewhere. Anyway, this is not an efficient way of doing things. Better do it by: - cloning the image - moving the clone 1 pixel - comparing the entire image with the clone with "-compose difference" - genera...
by rnbc
2011-09-13T03:24:54-07:00
Forum: Users
Topic: Finding isolated pixels.
Replies: 14
Views: 24971

Re: Finding isolated pixels.

Thanks, that was the problem, min only accepts two arguments! Dumb me!

I'll try to devise some faster method, but this one already works miracles for what I want :)
by rnbc
2011-09-12T18:05:30-07:00
Forum: Users
Topic: Finding isolated pixels.
Replies: 14
Views: 24971

Re: Finding isolated pixels.

It seems as if -fx runs left to right, up to down, and changes pixel values in place, so that I'm comparing with an already changed image, instead of comparing inside the original image and generating a new image. How can I compare inside the original image? Generating a new image with the result of...
by rnbc
2011-09-12T17:39:40-07:00
Forum: Users
Topic: Finding isolated pixels.
Replies: 14
Views: 24971

Re: Finding isolated pixels.

Hi fmw42. Sorry I didn't add to the discussion concerning HDR images the other day... I read it, but I had nothing to add really :P Just to clarify what an isolated pixel is, and is not: http://farm7.static.flickr.com/6066/6141866653_547525f970_o.png This image contains 9 isolated pixels, the others...
by rnbc
2011-09-12T17:09:04-07:00
Forum: Users
Topic: Finding isolated pixels.
Replies: 14
Views: 24971

Finding isolated pixels.

Hi! I'm trying to automatically detect hot pixels in a sensor. In order to do so I defined a criteria for "isolated pixel" which states that a pixel is more isolated if the difference to all it's neighbors is high. If the pixel has any close neighbor, even if only one, than it's not isolated. I'm ca...
by rnbc
2011-08-11T02:38:00-07:00
Forum: Digital Image Processing
Topic: Does Image Magick have Tonemapping operators?
Replies: 64
Views: 172851

Re: Does Image Magick have Tonemapping operators?

"90% of the result comes from the simplest 10% of the processing; it is the other 10% of the result that takes 90% of the effort"
I agree with you, but in art it tends to be that last 10% making the difference between vulgar and sublime, and this is as much science as it's art ;)
by rnbc
2011-08-10T08:18:52-07:00
Forum: Digital Image Processing
Topic: Does Image Magick have Tonemapping operators?
Replies: 64
Views: 172851

Re: Does Image Magick have Tonemapping operators?

Just a few thoughts... When defining a bilateral filter the question of "distance calculation" always arises, since this is where the magic is, so to say, and otherwise it's just a simple Gaussian blur. Some suggestions: - Luminance distance - RGB distance, as the distance between points in 3D space...
by rnbc
2011-08-10T02:50:41-07:00
Forum: Digital Image Processing
Topic: Does Image Magick have Tonemapping operators?
Replies: 64
Views: 172851

Re: Does Image Magick have Tonemapping operators?

The first images have small scale ringing, as you say. Maybe you can solve that simply by processing a larger image and than resampling to a smaller one? The last images have ugly halos... no good. Your efforts are interesting nevertheless. I think it would be really useful to implement some sort of...
by rnbc
2011-08-09T17:23:31-07:00
Forum: Digital Image Processing
Topic: Does Image Magick have Tonemapping operators?
Replies: 64
Views: 172851

Re: Does Image Magick have Tonemapping operators?

You must do some kind of post, since pfstools works in a linear scale space and monitors work in gamma ~2.0 or similar. Also the huge range of possible values inside an EXR (negative values, whiter than white) must be mapped into 8bit somehow... but in the last example my only "post" was conversion ...
by rnbc
2011-08-09T16:38:35-07:00
Forum: Digital Image Processing
Topic: Does Image Magick have Tonemapping operators?
Replies: 64
Views: 172851

Re: Does Image Magick have Tonemapping operators?

Try this one, without any post-processsing: ~tfc/pfstools/installed/bin/pfsin --frames 0:1:0 sala_com_janela.exr | ~tfc/pfstmo/installed/bin/pfstmo_mantiuk06 --factor 0.3 --saturation 0.8 | pfsgamma --gamma 2.2 --mul 1.0 | pfsoutexr --compression PIZ --fix-halfmax temp00.exr ; ~tfc/ImageMagick/insta...
by rnbc
2011-08-09T16:32:20-07:00
Forum: Digital Image Processing
Topic: Does Image Magick have Tonemapping operators?
Replies: 64
Views: 172851

Re: Does Image Magick have Tonemapping operators?

So yes, there is some post-processing, but the magic, shall we say, is made by mantiuk06. I think you should read the papers about those algorithms because there is a lot of tricks they use to convey contrast when there isn't contrast, and some of them are not obvious. For example, increasing the sa...
by rnbc
2011-08-09T16:22:54-07:00
Forum: Digital Image Processing
Topic: Does Image Magick have Tonemapping operators?
Replies: 64
Views: 172851

Re: Does Image Magick have Tonemapping operators?

The exact command line is a simplification of the general pipeline I suggested, since I only did tonemapping and post-processing, without blending with the high contrast scene again in the middle: ~tfc/pfstools/installed/bin/pfsin --frames 0:1:0 sala_com_janela.exr | ~tfc/pfstmo/installed/bin/pfstmo...
by rnbc
2011-08-08T19:40:37-07:00
Forum: Digital Image Processing
Topic: Does Image Magick have Tonemapping operators?
Replies: 64
Views: 172851

Re: Does Image Magick have Tonemapping operators?

I noticed the (large) halos, so I assumed you were using a highpass. I think mantiuk06 is one of the best available. It does true wonders! But durand02 and some others are also good. From the images I made available here as EXRs... mantiuk06: http://farm7.static.flickr.com/6079/6023916249_b6fffb5803...
by rnbc
2011-08-08T16:53:44-07:00
Forum: Digital Image Processing
Topic: Does Image Magick have Tonemapping operators?
Replies: 64
Views: 172851

Re: Does Image Magick have Tonemapping operators?

Well, basically you're filtering out low frequencies. Works somewhat, but the results are not that good... Now, before reinventing the wheel I think you should study the tonemapping algorithms available in pfstmo, because if you have such nice ideas before reading about them, I wonder what you'll be...
by rnbc
2011-08-07T20:15:56-07:00
Forum: Digital Image Processing
Topic: Does Image Magick have Tonemapping operators?
Replies: 64
Views: 172851

Re: Does Image Magick have Tonemapping operators?

Try: convert input.exr -auto-level -gamma 2.0 -depth 16 output.png I made the result available in the same place. It actually displays well because this image has a relatively low contrast. With higher contrast images you really need tonemapping. This will give you a 16 bit png with the luminance va...