(Bug number three. I can almost taste victory...)
If I compile ImageMagick with OpenCL support, the current version will hang
when I invoke the Gaussian blur operation. More specifically, the CPU will =
run
at 100%, and memory consumed by the process will increase indefinitely at 1=
9 MB
per second, but nothing will happen.
The blur operation is done internally for many other operations, so this is=
sue
is more crippling than it first appears.
To reproduce:
1. Get the current tree of ImageMagick from GitHub:
https://github.com/I=
mageMagick/ImageMagick
2. Compile it with OpenCL and HDRI support (--enable-opencl --enable-hdri
flags).
3. Get an image, and try to perform a simple Gaussian blur:
convert input.png -blur 0x20 output.png
4. The hang will occur... at least, on my system.
I mentioned this in another bug, and was told that on different hardware th=
an
mine (I have a Radeon HD 5700, which is an Evergreen chipset) all of the
ImageMagick self-tests pass.
The source code for all OpenCL kernels is in
MagickCore/accelerate-kernels-private.h. Several functions are involved with
blurring, and unfortunately it's difficult to identify the source of the ha=
ng.
I would be happy to provide debugging information if I could be advised on =
how
to collect it.
LLVM version: r292714
Mesa version: commit bb5db5564
ImageMagick version: commit 43a09ba75 (Note: the next git revision was brok=
en
by upstream)