Page 1 of 1

auto-orient introduces weird scan lines into images

Posted: 2009-06-29T15:50:10-07:00
by gotskill10
When running 'mogrify -auto-orient image.jpg' or the convert version of that command, the images are coming out like this:

http://upload.mixbook.com/images/broken.jpg

The original is here:
http://upload.mixbook.com/images/original.jpg

We are currently using: Version: ImageMagick 6.4.5 2009-05-23 Q8 OpenMP http://www.imagemagick.org
On a powerful EC2 64 bit instance.

Why is this happening? I searched for this bug, but cannot find it anywhere on the internet.

Re: auto-orient introduces weird scan lines into images

Posted: 2009-06-29T17:32:29-07:00
by magick
We could not reproduce the problem with the latest release, ImageMagick 6.5.4-0. You can try downloading and installing 6.5.4-0 or rebuild / reinstall 6.4.5 without OpenMP support (./configure --disable-openmp).

Re: auto-orient introduces weird scan lines into images

Posted: 2009-07-01T14:51:13-07:00
by gotskill10
recompiled it without OpenMP and it worked!

I know you guys had a thread about why you have OpenMP defaulted. I'd be against having it enabled by default since you are introducing potential bugs. It's like merging IM's bug list with OpenMP's bug list (along with the bugs that come with combining the two) without the user asking for it.

+1 for removing it from default ./configure.

Re: auto-orient introduces weird scan lines into images

Posted: 2009-07-01T18:29:10-07:00
by anthony
It is the default as it is faster on multi-processor machines. basically it divides a job into multiple 'threads' so that multiple processes can share the task and get it done faster.