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#337554 - 26/09/2010 10:50 Some photo editing advice wanted
BartDG
carpal tunnel

Registered: 20/05/2001
Posts: 2616
Loc: Bruges, Belgium
Hi all,

A couple of months ago, our baby daughter was born. I made some nice photo's during the birth, but had forgotten than I has set the camera (a Canon Ixus 6 megapixel) to it's lowest setting (half a megapixel, 640 * 480) a couple of days before because I wanted to take some pics then that needed to end up on some internet forum (so I needed low res pics). Stupidly enough, I never set the camera back to the original 6MP setting. I could could kick myself for being this careless, because the result is now all those nice pics were taken at the lowest quality setting of course. This is too low even for most photo book software to accept the photo as "good enough", so we can't even use them in a photo book. eek

Now, I know the chance is slim, but I figured I'd ask anyway: is there software out there that can blow up these pics, if only a tiny bit (double the size would be great!), so we could use them for a photo book? Of course, they should be enlarged *without* any quality loss... I know I can easily enlarge them the normal way with photo editing software, but that would result in blocky photos... not really what I'm after.
So... is there software out there that could do this for me, by using some type of intepolation algorithm? (preferably free software? whistle)

Thanks!
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#337555 - 26/09/2010 11:00 Re: Some photo editing advice wanted [Re: BartDG]
peter
carpal tunnel

Registered: 13/07/2000
Posts: 4172
Loc: Cambridge, England
Programs such as GIMP will do their best at this (sophisticated scaling algorithms), though of course it's fundamentally an unsolvable problem as no program can "restore" detail that was never there. You could try messing with blur or soften tools if the result is still too blocky. Or turn them mono or sepia, vignette them, and implicitly claim that the lack of resolution is a feature not a bug.

Though quite frankly, all newborns look the same to me. If you borrow some photos of a completely different baby then as long as you're careful with ethnic origin and eye colour you'd probably fool everyone except yourself and the missus... smile

Peter

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#337556 - 26/09/2010 11:09 Re: Some photo editing advice wanted [Re: peter]
BartDG
carpal tunnel

Registered: 20/05/2001
Posts: 2616
Loc: Bruges, Belgium
Originally Posted By: peter
no program can "restore" detail that was never there.

Isn't this exactly what those interpolation techniques do? Predict certain pixels based on the adjacent ones?

Originally Posted By: peter

Though quite frankly, all newborns look the same to me. If you borrow some photos of a completely different baby then as long as you're careful with ethnic origin and eye colour you'd probably fool everyone except yourself and the missus...

Agreed. Unfortunately, the missus does not agree with this point. smile
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#337558 - 26/09/2010 11:18 Re: Some photo editing advice wanted [Re: BartDG]
peter
carpal tunnel

Registered: 13/07/2000
Posts: 4172
Loc: Cambridge, England
Originally Posted By: Archeon
Isn't this exactly what those interpolation techniques do? Predict certain pixels based on the adjacent ones?

Yes, but that means that if there should be something going on in that pixel that couldn't be predicted from the adjacent ones, it's not recoverable. So the fine hair of a newborn baby, for instance, is likely to end up an Impressionistic blur.

Peter

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#337559 - 26/09/2010 11:29 Re: Some photo editing advice wanted [Re: BartDG]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14481
Loc: Canada
Originally Posted By: Archeon
Isn't this exactly what those interpolation techniques do? Predict certain pixels based on the adjacent ones?

A big part of the problem is, your camera has already done even that "for you", by saving the file as a reduced-data JPG image.

Reconstructing even the low-rez original image from the reduced-data JPG, taxes things fairly heavily.

-ml

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#337560 - 26/09/2010 11:39 Re: Some photo editing advice wanted [Re: mlord]
peter
carpal tunnel

Registered: 13/07/2000
Posts: 4172
Loc: Cambridge, England
BTW, while we're on about 0-day photographs of babies, here is something very cool that some friends of my aunt's did: go and buy 21 identical A4-size picture frames. Put (your best effort at) a 0-day baby photo in one of them. On her first birthday, take a photo of her holding that photo; put that in the second frame. On her second birthday, take a photo of her holding the first-birthday photo, and so on. My aunt's friends had complete 21-photo sets hanging on their walls for both of their grown-up children...

Peter

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#337561 - 26/09/2010 13:35 Re: Some photo editing advice wanted [Re: peter]
tanstaafl.
carpal tunnel

Registered: 08/07/1999
Posts: 5539
Loc: Ajijic, Mexico
Originally Posted By: peter
no program can "restore" detail that was never there.
Oh, c'mon now. We've all seen those CSI programs where they take a single frame from a low-resolution black and white ATM security camera and blow it up to display with crystal clarity the license plate of a speeding getaway car two blocks away. Surely they wouldn't engage in unwarranted exaggeration of their photographic capabilities, would they? Why, that would call into question the authenticity of all television programming.

tanstaafl.
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#337562 - 26/09/2010 13:58 Re: Some photo editing advice wanted [Re: tanstaafl.]
peter
carpal tunnel

Registered: 13/07/2000
Posts: 4172
Loc: Cambridge, England
Originally Posted By: tanstaafl.
blow it up to display with crystal clarity the license plate of a speeding getaway car two blocks away

CSI zoom-in is clearly bogus, for good, information-theoretic reasons. But there is a grain of truth in CSI blur removal: where you've got a good model for the blur, e.g. motion blur or Gaussian (camera-out-of-focus) blur, maximum entropy modelling can do a startlingly good job of computing the original image most likely to have produced the blurred image, though it's very computationally expensive. (And, just as with Mark's point above, you can't do it on JPEGs, which have already thrown away as "spurious" the fine detail that it depends on.)

Peter

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#337563 - 26/09/2010 13:59 Re: Some photo editing advice wanted [Re: BartDG]
tanstaafl.
carpal tunnel

Registered: 08/07/1999
Posts: 5539
Loc: Ajijic, Mexico
Originally Posted By: Archeon
Stupidly enough, I never set the camera back to the original 6MP setting.
Assuming your camera has sufficient storage capacity, and likewise your computer, you could do as I do and just leave your camera [b[always[/b] at the maximum resolution, and re-size the pictures as needed on your computer. This won't help you with your current situation, unfortunately.

I use a free program called PhotoReize400.exe that is both versatile and very simple to use. After installation, you have an executable program called something like PhotoResize_WxxxHyyy.exe where xxx and yyy are the number of pixels Width and Height you want the resized image to be. You can change xxx and yyy to be any value you want, I keep half a dozen or so copies of the program with commonly used values already defined. To resize an image, you just use Windows Explorer to drag the file onto the PhotoResize_WxxxHyyy.exe file, and it resizes the picture to the xxx by yyy specs and puts the resized copy in the same directory as the original file with "Wxxx" appended to the original filename.

Gaaahhh... this sounds so much more complicated than it is. Just drag your file (or a dozen or 20 of them at once if you want) onto the program and it puts resized copies into the source directory.

tanstaafl.
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#337564 - 26/09/2010 14:23 Re: Some photo editing advice wanted [Re: tanstaafl.]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14481
Loc: Canada
For Linux users (and probably Mac, and other *nix systems), one of the best programs for quick and easy photo manipulation is the shareware xv program. It is distributed as a C language source code package. Being shareware, though, you have to hunt for it, rather than just point-and-click in synaptic.

Informally known as the "swiss army knife" of image viewer/editors, xv really ROCKs!

I often wonder why Windows users have such a hard time posting photos, and the answer is probably lack of something as lightweight (to use) and capable as this.

Cheers

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#337568 - 26/09/2010 15:52 Re: Some photo editing advice wanted [Re: mlord]
andy
carpal tunnel

Registered: 10/06/1999
Posts: 5914
Loc: Wivenhoe, Essex, UK
Paint.net is an excellent lightweight Windows image editor, so it isn't down to a lack of availability.
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#337570 - 26/09/2010 16:31 Re: Some photo editing advice wanted [Re: andy]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14481
Loc: Canada
When I go to post a photo here, I generally do these exact keystrokes
(no mousing about, though I could if I wanted to):
Code:
xv reallybigphoto.cr2
<<s
<Alt-S>
<enter>
<Control-S>
(edit the filename to suit)
<enter>
<enter>
q

That sequence, which can also be done entirely as hunt-point-and-click with a mouse, imports the raw file, resizes the photo, smooths out the noise, sharpens the result slightly, and saves it as a JPG. Same sequence works regardless of the original file format. Takes (far) less than 10 seconds normally.

Not bad for something from the early 1990s, and it's still the best lightweight thing out there today.


Edited by mlord (26/09/2010 16:37)

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#337576 - 26/09/2010 17:28 Re: Some photo editing advice wanted [Re: mlord]
andy
carpal tunnel

Registered: 10/06/1999
Posts: 5914
Loc: Wivenhoe, Essex, UK
I take a very different approach to resizing my photos, all my photos get loaded straight on to my photo website. So when I need a resized photo I just load the photo in the site and edit the width parameter in the URL and post the URL to wherever I want to display the photo wink
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#337577 - 26/09/2010 17:34 Re: Some photo editing advice wanted [Re: andy]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14481
Loc: Canada
For our photo site here, I just run a totally automated script that takes the raw format files and processes them into resized JPG files of various sizes. That way it's still friendly to folks on slow links and dial-ups.

Cheers

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#337624 - 27/09/2010 17:00 Re: Some photo editing advice wanted [Re: mlord]
canuckInOR
carpal tunnel

Registered: 13/02/2002
Posts: 3212
Loc: Portland, OR
Originally Posted By: mlord
For Linux users (and probably Mac, and other *nix systems), one of the best programs for quick and easy photo manipulation is the shareware xv program.
Yeah... I used to love xv, but I lost track of it a long time ago, simply because it wasn't apt-get-able.

If you want fully free, then I'd suggest GraphicsMagick's convert or mogrify, though if you prefer seeing what's happening visually, display has keyboard shortcuts that let you avoid mousing, too. A little less light-weight than xv, but with the extra power, I prefer it.

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#337628 - 27/09/2010 17:14 Re: Some photo editing advice wanted [Re: tanstaafl.]
drakino
carpal tunnel

Registered: 08/06/1999
Posts: 7868
Originally Posted By: tanstaafl.
I use a free program called PhotoReize400.exe that is both versatile and very simple to use. After installation, you have an executable program called something like PhotoResize_WxxxHyyy.exe where xxx and yyy are the number of pixels Width and Height you want the resized image to be. You can change xxx and yyy to be any value you want, I keep half a dozen or so copies of the program with commonly used values already defined. To resize an image, you just use Windows Explorer to drag the file onto the PhotoResize_WxxxHyyy.exe file, and it resizes the picture to the xxx by yyy specs and puts the resized copy in the same directory as the original file with "Wxxx" appended to the original filename.

Thats pretty clever actually. For anyone here wanting to do similar on a Mac, just pop open Automator and build a "Folder Action" built with the "Scale Image" function. All built into the OS, no external programs needed. For simple one off resizes, Preview handles this just fine.

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#337727 - 29/09/2010 20:30 Re: Some photo editing advice wanted [Re: mlord]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14481
Loc: Canada
Originally Posted By: mlord
For Linux users (and probably Mac, and other *nix systems), one of the best programs for quick and easy photo manipulation is the shareware xv program. It is distributed as a C language source code package. Being shareware, though, you have to hunt for it, rather than just point-and-click in synaptic.


Hey, the author still exists (better link than above).

SWMBO was complaining that xv "grab" doesn't work properly in Ubuntu 10.04. So, we just spent an hour together poking through it, and fixed it with this one-word change to the sources:
Code:
--- xv-3.10a-CRW-ml/xvgrab.c.orig       2004-04-25 17:57:11.000000000 -0400
+++ xv-3.10a-CRW-ml/xvgrab.c    2010-09-29 17:54:30.993963669 -0400
@@ -107,7 +107,7 @@
 
   XBell(theDisp, 0);           /* beep once at start of grab */
 
-  if (!autograb) XGrabButton(theDisp, (u_int) AnyButton, 0, rootW, False, 0, 
+  if (!autograb) XGrabButton(theDisp, (u_int) AnyButton, ButtonPressMask, rootW, False, 0, 
                             GrabModeAsync, GrabModeSync, None, tcross);
   
   if (autograb) {

SWMBO has emailed the change to the author, too.

Cheers

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#337728 - 29/09/2010 21:47 Re: Some photo editing advice wanted [Re: mlord]
wfaulk
carpal tunnel

Registered: 25/12/2000
Posts: 16706
Loc: Raleigh, NC US
As a frame of reference, I submitted a patch to xv (still on the web page) 12 years ago. And it was long in the tooth then.
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