I've using ufraw through convert on Linux/ubuntu (UFRaw 0.18) to convert DNG files (processed with Lightroom, from my Canon EOS 40D) to JPG files. For some of the pictures this works well, for a lot of them I'm experiencing problems. The generated picture looks strange after conversion, some areas of the picture are missing.
You can find the original DNG file here:
This is the ufraw processed file:
This is the output of convert/ufraw:
sbe@home:~$ convert -verbose -resize 1400 -quality 90 IMG_4269.dng IMG_4269.jpg
"ufraw-batch" --silent --create-id=also --out-type=png --out-depth=16 "--output=/tmp/magick-LTE8Wk10.png" "/tmp/magick-niMF04wh"
Found a generic profile, type exif
/tmp/magick-LTE8Wk10.png PNG 3908x2602 3908x2602+0+0 16-bit DirectClass 35.98MB 0.970u 0:00.990
IMG_4269.dng=>/tmp/magick-LTE8Wk10.png DNG 3908x2602 3908x2602+0+0 16-bit DirectClass 35.98MB 0.020u 0:00.019
IMG_4269.dng=>IMG_4269.jpg DNG 3908x2602=>1400x932 1400x932+0+0 16-bit DirectClass 180KB 1.180u 0:01.219
Do you have any idea what is going wrong here?
I did some testing on Ubuntu 12.04 and found out that the 12.04 repository ufraw-batch (ver 0.18) will generate the block artifact as in your example jpg file. My self-installed version (0.19.2) does not. So installing the latest version of ufraw may solve your problem.
It seems your imagemagick (convert is part of it) is a repository version, which gets the delegate command for .dng files from /etc/ImageMagick/delegates.xml . If so, the above solution may be good enough.
My imagemagick is a self-installed version, which uses the magick/delegate.c file to hard-code delegate commands. It uses an absolute path for ufraw-batch and also has a few other errors. I made the following edits to make it work for me:
Changing both ppm to png works too.