Software correction of out of focus pictures?

Is there any software that can correct (to whatever degree) out of focus
pictures or is this impossible? I have tried Focus magic but not that
impressed. I don't know if there is any very clever maths that can work out
what the picture would have been like or if 'clever' focussing software
merely presents an 'illusion' of correction.

SS bedacht in :

Is there any software that can correct (to whatever degree) out of
focus pictures or is this impossible? I have tried Focus magic but not
that impressed. I don't know if there is any very clever maths that
can work out what the picture would have been like or if 'clever'
focussing software merely presents an 'illusion' of correction.



Although I haven't been in a position to compare different software
packages, I am reasonably happy with FocusFixer from Fixer Labs
(http://www.fixerlabs.com/New_Website...focusfixer.htm), a Photoshop
plugin.
It can do a good job with certain photos, but it can't perform miracles.

JL

Today Justus Lipsius commented courteously on the subject at
hand

SS bedacht in
:

Is there any software that can correct (to whatever
degree) out of focus pictures or is this impossible? I
have tried Focus magic but not that impressed. I don't
know if there is any very clever maths that can work out
what the picture would have been like or if 'clever'
focussing software merely presents an 'illusion' of
correction.

Although I haven't been in a position to compare different
software packages, I am reasonably happy with FocusFixer
from Fixer Labs
(http://www.fixerlabs.com/New_Website...focusfixer.htm),
a Photoshop plugin.
It can do a good job with certain photos, but it can't
perform miracles.

I haven't tried this particular product, but I agree with you in
principle. If the image is out-of-focus, it is out-of-focus.
Period, end of discussion. Everything else is aimed at creating
the illusion of in-focus, detailed, sharp images from ones that
aren't perfect in the first place. As you observe, they can't
perform miracles and their results vary according to how bad the
problem is and what the user's definition of "improved" might
be.

--
ATM, aka Jerry

"Whether You Think You CAN Or CAN'T, You're Right." – Henry Ford

"SS" writes:

Is there any software that can correct (to whatever degree) out of focus
pictures or is this impossible? I have tried Focus magic but not that
impressed. I don't know if there is any very clever maths that can work out
what the picture would have been like or if 'clever' focussing software
merely presents an 'illusion' of correction.

Focus Magic is the best I know of. Starting from a normal picture of
normal resolution, it's an impossible problem; Focus Magic does more
than most software can.
--
David Dyer-Bennet, , http://www.dd-b.net/dd-b/
RKBA: http://noguns-nomoney.com/ http://www.dd-b.net/carry/
Pics: http://dd-b.lighthunters.net/ http://www.dd-b.net/dd-b/SnapshotAlbum/
Dragaera/Steven Brust: http://dragaera.info/

"All Things Mopar" wrote in message
...
SNIP
I haven't tried this particular product, but I agree with you
in principle. If the image is out-of-focus, it is out-of-focus.
Period, end of discussion.

That is not correct. With similar techniques as were used to restore
Hubble Space Station's initial imagery, it is also possible to restore
some of the OOF information.

The result will not be perfect, because the truely lost information
will generate artifacts during the restoration process. It is also
important to have a good model for the de-focus. Some so-called
"blind" deconvolution algorithms estimate the blur function, other
methods require prior input of the model to be used.

This is an example of a deliberately Gaussian blur, Radius 2.0)
blurred image, before and after restoration:
http://www.xs4all.nl/~bvdwolf/temp/2027_ACR33_GB2.png
http://www.xs4all.nl/~bvdwolf/temp/2027_ACR33_GB2_IPRL.png

Bart

SS wrote:
Is there any software that can correct (to whatever degree) out of focus
pictures or is this impossible? I have tried Focus magic but not that
impressed. I don't know if there is any very clever maths that can work out
what the picture would have been like or if 'clever' focussing software
merely presents an 'illusion' of correction.

you can not only fix the focus,
but it will also catch / fix the subject
who had just stepped out of the frame!

really magic!!

Today Bart van der Wolf commented courteously on the subject
at hand

"All Things Mopar" wrote in message
...
SNIP
I haven't tried this particular product, but I agree with
you in principle. If the image is out-of-focus, it is
out-of-focus. Period, end of discussion.

That is not correct. With similar techniques as were used
to restore Hubble Space Station's initial imagery, it is
also possible to restore some of the OOF information.

With all due respect to someone I don't know, my first
reaction to your contradiction of my simple statement is,
well, horse****.

What did it cost to fix Hubble, several /billion/ dollars?
And, they did /not/ fix the out-of-focus images /after/ they'd
been downloaded to earth, those are toast (yes, they tried and
tried and tried, but never succeeded to any measurable
degree).

NASA engineers and astronomers colaborated to add software to
Hubble and some electronics (as I recall, but I'm no Hubble
expert) to compensate - not correct - the incorrect mirror
curvature grind to allow /new/ images to be in-focus, and then
through some pretty sophisticated - read: extremely expensive
mathematical techniques. And, the space inside Hubble the
astronaut had to work in was so tight and the chance to
irreparably damage the telescope was so high that nobody
really knew in advance if Hubble could or could not be fixed.

What we're talking about here isn't NASA stuff, it is simple
"I blew the focus lock on my digital - how can I fix it now?"
stuff.

The result will not be perfect, because the truely lost
information will generate artifacts during the restoration
process. It is also important to have a good model for the
de-focus. Some so-called "blind" deconvolution algorithms
estimate the blur function, other methods require prior
input of the model to be used.

What kind of techno babble is this? Somebody who blows
vacation picture(s) are supposed to use "other methods require
prior input of the model to be used", whatever that means. I'm
supposed to know in advance exactly how I blew it, so the
software knows how to begin? If I'm misunderstanding you, I
apologize but I fail to see how someone can predict the way(s)
to blow a focus.

This is an example of a deliberately Gaussian blur, Radius
2.0) blurred image, before and after restoration:
http://www.xs4all.nl/~bvdwolf/temp/2027_ACR33_GB2.png
http://www.xs4all.nl/~bvdwolf/temp/2027_ACR33_GB2_IPRL.png

What you did here was what I previously said - you created the
/illusion/ of in-focus, and along with it, some really nasty
defects in the background looking like some weird cross
between noise and JPEG artifacts. You even said in the
paragraph above that the "restoration" process creates those
artifacts!

I suppose if somebody had some "once in a lifetime" photos
they blew, they could spend whatever time it takes tweaking
them through various means fair and foul and "save" it, but
there simply is no substitute for doing it right the first
time.

I could show you plenty of examples of my own "work" where I
blew the AF lock for one reason or another and used ordinary
PSP 9 techniques to make it /look/ a little more in-focus, but
it is still what it is - out-of-focus.

There's another theoretical vs. practical debate that goes on
occasionally involving whether one can or cannot do a large
scale enlargement of a digital image. I don't mean 1 1/2X
linear, I mean 4X+, meaning 16X+ pixel resolution area. As
with re-focusing out-of-focus images, the sophisticated math
behind these algorithms, of which Genuine Fractals is an early
but well known example, produces the illusion of enlargement
without blocking or pixelation or artifacts usually assocated
with large scale resizing up. But, even expensive enlargement
software requires /lots/ of user input to get it right, and
/always/ results in compromising one part of the image to get
another to look OK. Naturally, people concentrate on the main
subject and let the foreground and background go to hell in a
similar fashion to what happened to your heart-against-the-
foliage re-focus example.

Before you or someone else decides to take me on about this,
please keep this in mind: I am a pragmatist, not a
theorotician. I am also not an elitest. I deal in reality. I
understand the various subjects being discussed in this thread
in principle, some better than others. But, I spend very
little time when making a buying decision or anything else on
what the lab tests show or what a PhD in mathematics has
"proven". I rely on what I can actually see. Two sayings come
to mind here - "the proof of the pudding is in the eating" and
"I don't know anything about art, but I know what I like.

Do whatever floats your boat and I'll do the same. And, you
have a good evening, hear?! grin

--
ATM, aka Jerry

"Whether You Think You CAN Or CAN'T, You're Right." – Henry
Ford

Today bob crownfield commented courteously on the subject at
hand

SS wrote:
Is there any software that can correct (to whatever
degree) out of focus pictures or is this impossible? I
have tried Focus magic but not that impressed. I don't
know if there is any very clever maths that can work out
what the picture would have been like or if 'clever'
focussing software merely presents an 'illusion' of
correction.

you can not only fix the focus,
but it will also catch / fix the subject
who had just stepped out of the frame!

I could really use this when I cut somebody's head off! grin

really magic!!

--
ATM, aka Jerry

"Whether You Think You CAN Or CAN'T, You're Right." – Henry Ford

All Things Mopar wrote:
What you did here was what I previously said - you created the
/illusion/ of in-focus, and along with it, some really nasty
defects in the background looking like some weird cross
between noise and JPEG artifacts. You even said in the
paragraph above that the "restoration" process creates those
artifacts!


I'm fed up with contradictions about image manipulation but I can't help
pointing out to you - whoever you are - that a little knowledge is
dangerous. You do not comprehend how an advanced process can sharpen an out
of focus image. If you did, you would not be so quick to get up the nose of
Bart.

Sharpness is a perceived thing. I resharpen out of focus and slightly motion
blurred images by recognizing the perception and actually blurring a lot of
the image even more than the amount I correct. The result is an image which
is perceived to be sharp(er).

The process is used by NASA although their routine is a little different to
mine. I convert edges to vector and blur the bitmap, re-applying the vector
after it has been narrowed. This produces the perception of sharpness due to
the fuzz from the edges being gone and the fill detail being smudged.

Although Photoshop has all the tools for doing this, you might not get the
results I do. Go ahead and try it. Even if you stuff it up (as you no doubt
will in PS) you will learn that it is indeed possible.
--
www.photosbydouglas.com
www.weprint2canvas.com
If you really must write,use my
name at an above domain.

All Things Mopar wrote:

Today Bart van der Wolf commented courteously on the subject
at hand

"All Things Mopar" wrote in message
...
SNIP

I haven't tried this particular product, but I agree with
you in principle. If the image is out-of-focus, it is
out-of-focus. Period, end of discussion.

That is not correct. With similar techniques as were used
to restore Hubble Space Station's initial imagery, it is
also possible to restore some of the OOF information.

With all due respect to someone I don't know, my first
reaction to your contradiction of my simple statement is,
well, horse****.

Bart is correct. The technology to improve focus is called image
deconvolution, or image restoration and has been a topic
of research for decades, well before the Hubble problem.
One of the more successful algorithms is Richardson-Lucy
Image Restoration. Photoshop's tools, like unsharp mask
do not actually sharpen, they only change accutance.
A combination of edge detection and unsharp masking, a method
developed by Bob Atkinson, can come close to equal it however
(I'll be adding this to my web page sometime; test done by
Bill Hilton).

See:
Image Restoration
Using Adaptive Richardson-Lucy Iteration
http://www.clarkvision.com/imagedeta...e-restoration1

Image Restoration Using the Damped Richardson-Lucy Method
http://www.stsci.edu/stsci/meetings/...er_damped.html

There is no RL pluggin for Photoshop that I am aware of.
Bart and I both use an image processing program called ImagesPlus
which has this and other image restoration algorithms.

Basically, the concept is this: consider a blurred image, e.g.
due to focus, or motion. Adjacent pixels have image information
of other pixels. Using a model of the blur, the software
estimates the contribution of the blur to each pixel and
moves that signal back to adjacent pixels. It is an iterative
process and takes a lot of computation, but can work very well.
But there is no free lunch. The process increases noise, and
can cause ringing artifacts if done to extreme, and/or if the
blur model doesn't match the image.

In my own experiments, it seems there is roughly an even trade
in noise versus resolution. My digital workflow now includes
RL restoration on any image I intend to print large. I routinely
double the pixel count in each dimension and produce very sharp
large prints (e.g. 16x24 inches) from 8-megapixel images.

Roger