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CR2 to JPG conversion slow - or is 16 seconds normal?

Posted: 2015-04-03T09:12:26-07:00
by mercatore
Hi,
I have an 3.4GHz i7 Mac and have installed ImageMagick from Homebrew. I am using
convert XYZ.CR2 XYZ.jpg
to convert a Canon RAW to jpg. It takes 16-17 seconds. Compiled with OpenMP and OpenCL but no change. Is this a normal conversion time? Seems to be terribly long...
Thanks for any hint,
Mercatore

Re: CR2 to JPG conversion slow - or is 16 seconds normal?

Posted: 2015-04-03T11:56:14-07:00
by snibgo
On my i7 Windows laptop, converting a 5364x3753 cr2 takes about 3 seconds. This uses dcraw as the delegate.

You might use "-verbose" to see what delegate is used. I don't know if ufraw is slower than dcraw.

Re: CR2 to JPG conversion slow - or is 16 seconds normal?

Posted: 2015-04-03T16:28:28-07:00
by mercatore
Thanks. It uses ufraw. I have tried draw and it still is around 7-8 seconds. Would you let me know the options you are using for calling dcraw?

Re: CR2 to JPG conversion slow - or is 16 seconds normal?

Posted: 2015-04-03T16:51:24-07:00
by snibgo
For this test, I did just:

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dcraw -T -6 -O x.tiff sample.cr2
Going via ImageMagick (which I don't normally):

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f:\web\im>%IM%convert -verbose sample.cr2 x1.jpg

dcraw.exe -6 -w -O "C:/Users/Alan/AppData/Local/Temp/magick-2532ilj-wSLWLUpx.ppm" "C:/Users/Alan/AppData/Local/Temp/magick-2532cetMk3b_2Crx"

Re: CR2 to JPG conversion slow - or is 16 seconds normal?

Posted: 2015-04-03T17:11:53-07:00
by mercatore
Thanks, that was fast... When I go to dcraw, I get down to about 4.5 seconds. A bit frustrating when I look at the speed I theoretically have... Not that I do not have the -O option on the Mac but must pipe it to stdout and from there into a file.

Re: CR2 to JPG conversion slow - or is 16 seconds normal?

Posted: 2015-04-03T17:16:12-07:00
by mercatore
One more: Can I change the "standard delegate" along with the standard options, such as -q 2 in a config file or alike?

Re: CR2 to JPG conversion slow - or is 16 seconds normal?

Posted: 2015-04-03T18:25:13-07:00
by snibgo
Yes. In the directory that contains convert.exe is the text file delegates.xml. Look for a line that contains "dng:". For me, this line is:

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  <delegate decode="dng:decode" stealth="True" command="dcraw.exe -6 -w -O "%u.ppm" "%i""/>
I can add dcraw options, or use a different program.