I've tried every image viewer for Linux that I could find; DigiKam, GThumb, Eye of Gnome, Gwenview, etc, and none of these image viewers can view images as fast as ACDSee, and many of them don't have an option for directory tree view.

I work as a photographer, and I have to go through hundreds, sometimes thousands, of pictures every week. If I have to wait 2 seconds for each image to load, an extra hour would likely be added to my work schedule. And with hundreds of directories to go through, I would prefer to view them as I have them on my hard drive.

The only viewer that I've found that even comes close to ACDSee is Picasa. But here is the kicker... The Linux version of Picasa uses Windows components and Wine to run!

Is there something about the Linux kernel that makes fast image viewing impossible? And why do so many image viewers not bother with adding a directory tree view? This makes no sense.

Uuuhhh, I don't use Wine and Picasa works fine on my Linux box. The requirements for Picasa are
Intel 386-compatible processor, glibc 2.3.2 or greater, working X11 display system, current version of Gnome or KDE for desktop integration, kernel >= 2.6.13, hal >= 0.56, libgphoto2, and gnome-volume-manager or equivalent for camera detection.

The poor performance is not necessarily the fault of the image viewers but of the default way file access times are handled. Basically every time you access a file (not modify it but simply access it) there is an access time written to disk.....yup, every read means a write!!! It stinks but it's easy to fix. You need as root to edit /etc/fstab and add the noatime option to prevent this so, for example, if the line for your / and /home partitions look like this:

you can change them to look like:

Now a simple access/read won't cause a write to disk and the performance of your system should be markedly better on any task which involves a lot of reads. I find images load instantly using gthumb or gqview and ever so slightly slower with f-spot.

edit:you'll need to unmount/remount the disks (rebooting is easiest way)

The image viewer I use is GQView. It's the fastest linux image browser I've used so far. It's as fast as an old version of ACDSee I used to use.

Sometimes, I try out a different image browser, but I always end up disappointed by the speed. I return to GQView. Note that you can change the method of image scaling. The fastest is "nearest pixel", which usually looks horrible for low resolution images, but it's not bad for high resolution digital photos.

For browsing high resolution digital photos, I definitely prefer GQView over ACDSee. I don't know if it has a "directory tree" view. I just got used to the way GQView does things and now I find the way ACDSee does things kludgy and a bit annoying.

I severely doubt this is the problem. With all of the image browsers I've tried so far, the bottleneck is invariably CPU processing time for jpeg decoding and rescaling. I think many linux image viewers decode the entire jpeg before it starts displaying...which makes browsing sluggish for high resolution images. I don't really know why exactly GQView is zippier than other image browsers. The bottom line is that it's faster, by enough for me to choose it over other image browsers.

I use GQView when viewing collections of pictures, but for a single one I just use feh launched by my file browser.

When you load into an image viewer a folder containing hundreds of image files it has to be a factor that each individual image file causes an individual write to disk unless noatime option is used. Another factor to consider is that the images, unless they are new, already have thumbnails cached, it's these thumbnails which will initially be displayed and should load immediately. These thumbnails are typically under 100 kB in size and in png format so jpeg decoding and image scaling shouldn't be any kind of issue. Of course when loading new images these are factors, as they are when loading individual images (as opposed to viewing thumbnails).

You may not use WINE, but Picasa (even the Linux version) does. Check your .picasa folder.

Interesting. I never knew about this. I'll give it a try and let you know how it works.

I think you'll find a distinct benefit right across the board and there is no downside at all. Afaik access times handled the default way are only important when running mail servers or if you perform thorough security audits, for the vast majority of users they're an irrelevance and do nothing except negatively impact performance. Some distros use noatime by default and you'll see more and more distros using noatime and relatime options. You can find out more about the issue at Kerneltrap - Linux: Replacing atime With relatime where Linus Torvalds and others discuss it and note performance gains between 10% and 50%(!) by using noatime instead of the default (atime).

Here's a couple more you might try: gtksee, gimageview, iv
gtksee is a clone of ACDSee. I also use GQview for viewing a directory full of images.

Well, I'll be! Never looked before.

@Cinematography

What photo editing software do you use ?
Lightzone? Gimp? or anything else?

I did notice some improvement, but it still takes between 1 to 2 seconds for a simple 7mp jpeg to load. I think the problem may be with the programming. Most people don't need images to load fast, so the developers work more on the features than the speed. For the average person, a 2 second load time is just fine.

I wish Feh had more features.

Unfortunately I've already tried all of those.

But thank you for the suggestions.

I use Photoshop CS. Gimp needs too much RAM for some reason. And I've never heard of Lightzone. I'll look it up.

I think it's more the fact that libraries to decode .jpeg/.png/.gif/etc files already exist. So most open source programmers use the existing code instead of developing their own code from scratch.

Have you tried changing the settings on GQView? By default, it uses a processor intensive but very nice looking bilinear scaling routine. But it'll display faster by using the fast but ugly "nearest pixel" scaling routine (which is the same method ACDSee uses, or at least it's the method used by the old version of ACDSee I used to use).

For a 7 megapixel photo, though, "nearest pixel" scaling will look just fine. You'll get a performance boost without really sacrificing scaling quality.

Another way to tune GQView is to turn OFF two pass rendering. To me, this is just a waste of time.

Another thing that affects speed is thumbnails. Personally, I always turn off thumbnail caching in GQView. I suppose it might be nice if I actually used thumbnails, but I don't. I find thumbnails to be too tiny to be very useful. Most of the time, I'd rather flip through the images in a full screen window. For me, generation of thumbnails is just something that slows things down and needlessly clutters up disk space.

I love lightzone, it's a trial version for linux, but if you want i can send you the previous full version for linux. it's really worth a try