Bad pixels present even after successfully creating badpixel.bin

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Bad pixels present even after successfully creating badpixel.bin
« on: 22 / November / 2015, 15:41:16 »
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Hello there.

I own ELPH 300 HS and I have problems with stable release http://mighty-hoernsche.de/bins/ixus220_elph300hs-100c-1.3.0-4272-full.zip

I've successfully created bad pixel I followed this guide: http://chdk.wikia.com/wiki/Badpixel_removal but my raw files still have ton of bad pixels. There is one particularly noticable (green one) you can spot it without zoom. But if you zoom you can see a ton of others bad pixels (I think they are bad pixels).

I've attached badpixel file and here is raw image:  https://www.dropbox.com/s/ak4s6bwzwvuv1ak/CRW_4145.DNG?dl=0

Any ideas how can I get rid of bad pixels?

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Offline philmoz

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Re: Bad pixels present even after successfully creating badpixel.bin
« Reply #1 on: 22 / November / 2015, 16:30:49 »
Hello there.

I own ELPH 300 HS and I have problems with stable release http://mighty-hoernsche.de/bins/ixus220_elph300hs-100c-1.3.0-4272-full.zip

I've successfully created bad pixel I followed this guide: http://chdk.wikia.com/wiki/Badpixel_removal but my raw files still have ton of bad pixels. There is one particularly noticable (green one) you can spot it without zoom. But if you zoom you can see a ton of others bad pixels (I think they are bad pixels).

I've attached badpixel file and here is raw image:  https://www.dropbox.com/s/ak4s6bwzwvuv1ak/CRW_4145.DNG?dl=0

Any ideas how can I get rid of bad pixels?

You've selected DNG version 1.3 in the CHDK Raw menu.

Version 1.3 does not need a badpixel.bin file, it writes an instruction to the DNG file to tell post processing software to handle the bad pixels.

Unfortunately only Adobe software seems to do this, despite the fact that it has been part of the standard for many years.

If you select DNG version 1.1 in CHDK, then the bad pixel removal will be done in-camera (which takes a bit longer depending on how many bad pixels you have).

Phil.
CHDK ports:
  sx30is (1.00c, 1.00h, 1.00l, 1.00n & 1.00p)
  g12 (1.00c, 1.00e, 1.00f & 1.00g)
  sx130is (1.01d & 1.01f)
  ixus310hs (1.00a & 1.01a)
  sx40hs (1.00d, 1.00g & 1.00i)
  g1x (1.00e, 1.00f & 1.00g)

Re: Bad pixels present even after successfully creating badpixel.bin
« Reply #2 on: 22 / November / 2015, 16:49:29 »
@philmoz can you tell what version of  DNG is by looking at dng file itself? If so what software do you recommend (Linux wise).

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Offline reyalp

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Re: Bad pixels present even after successfully creating badpixel.bin
« Reply #3 on: 22 / November / 2015, 16:55:33 »
The DNG version is part  of the DNG header. exiv2 or exiftool should show you.

FWIW, if you use raw therapee, the "dead / hot pixel" filter should do a fairly good job with the dead pixels you see in dng 1.3, even though it doesn't support the opcodes.

You can also use chdkptp to patch them, or generate a list for use with raw therapee. See https://www.assembla.com/spaces/chdkptp/wiki/DNG_Processing
Don't forget what the H stands for.


Re: Bad pixels present even after successfully creating badpixel.bin
« Reply #4 on: 23 / November / 2015, 05:13:17 »
@reyalp thank you for the suggestion!

I'll try it when I get home. I tried ufraw before and I was shocked at how many dead / hot pixels are there :) I have a lot of image processing on to-do list and if I can do it natively in Linux even better!

Re: Bad pixels present even after successfully creating badpixel.bin
« Reply #5 on: 25 / November / 2015, 15:20:55 »
@reyalp,

I've created bad pixel list bad.txt (attachment). But I don't know how to apply it in Raw Therapee. Can you please tell me how can I do it?

I have Raw Therapee 4.0.1

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Offline reyalp

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Re: Bad pixels present even after successfully creating badpixel.bin
« Reply #6 on: 25 / November / 2015, 15:57:43 »
@reyalp,

I've created bad pixel list bad.txt (attachment). But I don't know how to apply it in Raw Therapee. Can you please tell me how can I do it?
FWIW, I'd suggest trying with just the "Hot pixel" and "Dead pixel" options checked in the preprocessing section of the raw tab.  See http://50.87.144.65/~rt/w/index.php?title=Preprocessing

For information about using an explicit list it goes in the dark frame directory and is named <camera model>.badpixels, see http://50.87.144.65/~rt/w/index.php?title=Dark_Frame#Bad_Pixels

edit:
I'm an unclear which version(s) of raw therapee the +4 pixel thing in the above refers to. The chdkptp command mentioned above does not account for this.

Quote
I have Raw Therapee 4.0.1
This is quite old, their "stable" is up to 4.2 something. My suggestions above may not be correct for this version, I believe the bad pixel options were improved in 4.2
« Last Edit: 25 / November / 2015, 17:20:58 by reyalp »
Don't forget what the H stands for.

Re: Bad pixels present even after successfully creating badpixel.bin
« Reply #7 on: 26 / November / 2015, 15:50:04 »
I upgraded to 4.2 and I still see a lot of bad/hot pixels. And I feel so clumsy because I can't seem to find preferences icon in Raw Therapee. Here is print screen of a Raw Therapee: http://i.imgur.com/X01YOrn.jpg (You can also see a lot of bad/hot pixels on this image even though I've checked dead/hot pixel in Preprocessing).

1) Is preferences window opened from terminal?

2) Do I have to do something else beside enabling dead/hot pixel in Preprocessing?


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Offline reyalp

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Re: Bad pixels present even after successfully creating badpixel.bin
« Reply #8 on: 26 / November / 2015, 16:13:55 »
I upgraded to 4.2 and I still see a lot of bad/hot pixels. And I feel so clumsy because I can't seem to find preferences icon in Raw Therapee.
It's accessed from an icon with sliders file browser tab. See http://50.87.144.65/~rt/w/index.php?title=Getting_Started (bottom left of the first screenshot, but may vary depending on setttings)
Quote
Here is print screen of a Raw Therapee: http://i.imgur.com/X01YOrn.jpg (You can also see a lot of bad/hot pixels on this image even though I've checked dead/hot pixel in Preprocessing).
...
2) Do I have to do something else beside enabling dead/hot pixel in Preprocessing?
It looks like those are mostly clusters of multiple pixels together. Some cameras do this. Perhaps raw therapee dead pixel code doesn't handle those.

edit:
If your camera has enough free RAM that the badpixel.bin doesn't cause low memory problems, using DNG 1.1 should be fine. The performance impact from patching is pretty minor, generally tens of milliseconds IIRC.

Of course that doesn't help with shots you already took.

Assuming you generated the bad.txt with chdkptp, you could just use it to fix your existing files, something like
dngbatch path/to/files {mod -patch; save -over -keepmtime}

This will overwrite the existing files, so you might want to make sure you have a backup copy first in case something goes wrong, or use the odir option to as in the example on the chdkptp wiki.
« Last Edit: 26 / November / 2015, 16:36:40 by reyalp »
Don't forget what the H stands for.

Re: Bad pixels present even after successfully creating badpixel.bin
« Reply #9 on: 27 / November / 2015, 17:00:54 »
@reyalp thank you so so much! :)

I love dngbatch and chdkptp in general! Thank you for tips on Raw Therapee. I've successfully use list of bad pixels and I'm so happy I can work on those (nto too many 248 dngs :P).

Thank you again. You saved the day!

 

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