XnView Software

yeah, this one http://j2k-codec.com/ claims to be 10x faster than jasper or openjpeg.
not free though...

I know that some comparison can be unfair.
I don't often deal with jpeg2000 files but I recently had to work with some old book scans (appears not uncommon for librarians to rely on this formats when scanning their collection).
and much to my surprise, it appeared that xnview/xnviewMP took a very ...

Yes, it would be great if this gamma issue could be fixed.

I suppose the use alpha for thumbnail is something I can live with... as the viewer gives more control.
in any case, if additional functionality for how thumbnail uses the alpha was to be implemented IMO this is not something that should be generic or even file format base but rather thumbnail based ...

for previews/view mode
just hit ctrl+h (or "view" > "use alpha channel")
ctrl+M (or "view" > "show alpha") is quite handy too...
now that's actually feature richer than Bridge isn't it ?

As for the gamma issue, maybe it has to do with the color profile used here "sRGB IEC61966-2.1 ( linear )" ?
for ...

At the very least, You need to provide:
installed XnViewMP version ! (win?, linux?, OSX?, 32 or 64bit?)
your Operating system (windows 7 ultimate x64?, OSX 10.7.3? , Ubuntu 11.10 32bit?, ... )
Additionally you may also want to provide and check some specific installation details that may ...

if on a hurry, you may want to give Mysticthumbs a try.
(from my experience: awesome utility with extensive file type compatibility & top notch support)

Most likely you swapped the results from PngOptimizer and PNGOut ;-)

I didn't swap any results!
please note that my test was run not with one particular BMP but with 55 png (a good number of them had transparency).
also, you don't seem to provide processing time, which I believe is quite ...

When xnviewMP 0.38.7 encounters these files, it crashes with
Unhandled exception at 0x670015d3 in xnview.exe: 0xC0000005: Access violation writing location 0x39e63b62.

Confirmed.

files details:
Image
------
resolution: 128x128
type: 128 Bits (RGBA)
channels Available: (RGBA) Half Float (16 ...

the issue always occur when navigating "too" quickly. (seems to occur more specifically when going "next/prev" while the current image is still being decoded (displayed as low-res)

2 test case (win7 x64):

case 1 : 1 folder of 400 jpg+CR2 (5200 x 3400)
case 2 : 1 folder of +/- 1000 average res ...

nope there definitively is a bug in there, it actually happens all the time when navigating a high-res picture folder.
MP is unusable for me like this.
let me know how I can help in solving this issue.

alternative:
1. Install xnviewMP
2. discover that .exr , .hdr and .rpf among many others are supported natively and works perfectly fine.

Actually now that I re-think of it...
When referring to the space surrounding the image thumbnail itself,
" Padding " should be renamed to " Margin " if moved into the "Thumbnail" group like I suggested.
(for the sake of symmetry you could even rename it to " Spacing " to match the "Thumbnail cell ...

Another Setting screen that is currently wrong:

I was just speculating on the occurrence of the buggy behavior.
the issue is: the viewer get stuck in low-res (scaled up) preview. (happens only on large file)