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Difference between Canon CRW and CHDK CRW?

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Re: Difference between Canon CRW and CHDK CRW?
« Reply #10 on: 17 / July / 2008, 02:39:01 »
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Maybe someone can explain if I'm doing something wrong:

(First things first: running Allbest v100c on an A720is. Also running Windows Vista.)

So I read here:

Canon RAW CR2 and CRW Thumbnail support in Vista | HCW Tech Blog

that I can install the Canon RAW Codec and then my RAW images will have thumbnails and be able to be opened in Windows Live Photo Gallery.

So I've done that, but still no thumbnails, and Live Photo Gallery is telling me the file's corrupted.

My *guess*, especially based on what I read in this thread, is that a Canon-produced RAW file in a camera that supports it is different than a CHDK-produced RAW file, and therefore the Canon RAW codec is worthless to me.

Is that the case? Has anyone gotten CHDK to produce RAW images with an A720is that the Canon RAW Codec can successfully read? Or do I need to seek out some other workflow?

Thanks much!

-- Chris

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Offline LjL

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Re: Difference between Canon CRW and CHDK CRW?
« Reply #11 on: 17 / July / 2008, 07:29:37 »
The format that CHDK output is definitely different from both CRW and CR2.

It only contains the raw image data, with no metadata or headers. You could arguably say it's not a format at all.
However, dcraw-based software can read it fine. I have no clue about codecs that can integrated with the Windows shell, though.

I'm currently working on making CHDK output standard CRW files (and/or DNG), but while I have the framework ready and a superficial but usable knowledge of the format, I think it will take a little time.

Re: Difference between Canon CRW and CHDK CRW?
« Reply #12 on: 17 / July / 2008, 11:53:33 »
The format that CHDK output is definitely different from both CRW and CR2.
Gotcha. I just wanted to be sure that I wasn't doing something wrong or missing some setting or something that would make it work.
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However, dcraw-based software can read it fine.
Yes, I've discovered that...I saw a reference to RAW Therapee above, and that seems pretty neat, 'cept for a tendency to save a separate .pp2 file every time you open something (I'm a bit of a neat freak with my Pictures folder). I'm guessing that the PP stands for post-processing, and it's cool that it keeps a record, but they could have found a less-cluttery way to store those.

(I'm a bit of a photo-n00b. Does it show? :))

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I have no clue about codecs that can integrated with the Windows shell, though.

The workflow I seem to be seeing, eliminating RAW Therapee as an option (though it would be an option if I could figure out how to mitigate that .PP2 thing), is to convert the thing to DNG (using dng4ps2) and then installing the codec from Adobe. This gets me thumbnails and the resulting file is openable in Photo Gallery, but sadly Photo Gallery is unable to do any post-processing on the file. So it's not perfect, but it's a start.
« Last Edit: 17 / July / 2008, 12:01:34 by clemon79 »

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Offline carlos

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Re: Difference between Canon CRW and CHDK CRW?
« Reply #13 on: 17 / July / 2008, 13:16:42 »
clemon 79,

Very responsive and helpful people at the RawTherapee FORUM .... ask re "that .PP2 thing"?

When I'm happy with the image, I delete the PP2.

carlos











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Offline carlos

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Re: Difference between Canon CRW and CHDK CRW?
« Reply #14 on: 19 / July / 2008, 01:08:52 »
Discovery  ??? :

.pp2 files are not saved if the checkbox "Save processing parameters with image" in pop-up window "rt.exe" (@ "Save Image - As...") is not checked.


Re: Difference between Canon CRW and CHDK CRW?
« Reply #15 on: 14 / September / 2009, 12:55:00 »
Ok.  I have my new port dumping (sd780) a really raw image.  However even rawtherapee does not open it...  How do I determine if the file that is being dumped is valid in any way?  The raw is 12-bit.   I've read that I may need to add a new setup to dcraw for my new camera?    Should I drop RAW entirely and use DNG for determining if things are going ok?

I'm a little confused how I should debug a RAW output that has no format.  LOL

Any advise or links are appreciated.


Thanks,
Harpo 
Canon Models - SD300, SD780, & SX210

Re: Difference between Canon CRW and CHDK CRW?
« Reply #16 on: 21 / April / 2010, 15:40:27 »

I'm currently working on making CHDK output standard CRW files (and/or DNG), but while I have the framework ready and a superficial but usable knowledge of the format, I think it will take a little time.

In the meantime, it would also be absolutely great IMHO if there was some post production tool to open CRWs, get EXIF data from the corresponding JPGs, and save CRW with EXIF data, a sort of of dng4ps2 but without raw to dng conversion.

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Offline reyalp

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Re: Difference between Canon CRW and CHDK CRW?
« Reply #17 on: 22 / April / 2010, 01:37:23 »
a sort of of dng4ps2 but without raw to dng conversion.
DNG is a raw format, which contains the same data (except for badpixel interpolation) as a CHDK CRW.
Don't forget what the H stands for.


Re: Difference between Canon CRW and CHDK CRW?
« Reply #18 on: 23 / July / 2010, 11:02:44 »
DNG is a raw format, which contains the same data (except for badpixel interpolation) as a CHDK CRW.

(Sorry for the delay, I hadn't switched on "Notify me of replies", I've just seen it among the "Additional Options".)

When I wrote the suggestion, I was playing with the trial of a commercial application with interesting features for geometric distortion correction and noise reduction. For the latter, their web site said they need the very raw data, and actually the application could not open DNG files at all (I had read around here that this application was not the only case). When trying to open the raw files from CHDK (SX110 IS), it only seemed to complain about the lack of EXIF data.

I'm not into the matter enough to evaluate on this. Also, maybe since then they have added the possibility to open DNG, or to open CHDKraw+jpg just as dng4ps does, I didn't keep following developments (I'm not much into shooting stills in this period of my life... I might take a little time though to go back to their website and see if they have a features request input).

Maybe with an insight on C/C++ programming and on where/how to store exif data in a raw file, and starting with the dng4ps framework... and of course with the appropriate C/C++ development kits installed... (actually, maybe it could even be an option for dng4ps, "write raw file(s) with embedded exif data", transcending the name "DNG4ps", but that might imply bothering the creator of the tool about evaluating/adopting a new version of it).

Of course, it is also possible that CHDK raw and the_other_raw_format(s)_various_apps_currently_open are just plain different content (but again, that application for a start only seemed to complain about the lack of exif data).
« Last Edit: 23 / July / 2010, 11:36:19 by TinTin »

Re: Difference between Canon CRW and CHDK CRW?
« Reply #19 on: 23 / July / 2010, 12:09:17 »
I might take a little time though to go back to their website and see if they have a features request input

Done, posted feature request.

 

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