Automatic preview generation for Netbook usability

[ba1212]

Hi

I believe this may help Photo Mechanic become much more responsive with under-powered CPUs, such as those used in netbooks. Slow CPUs tend to take a long time  building previews and, as only 5 previews are generated at any one time, this is not helpful when trying to scroll quickly through tens or hundreds of images.

Could Photo Mechanic have an option to automatically build non-zoomed previews for all images on ingest, and possibly also as a command to run on the current folder? This would mean in the field, I could ingest 30 images at a time, and let the netbook automatically build previews for those until I'm ready to scroll through and process them. It could be configured to fill up the ram cache, replacing old cached items.

However, this would only work if there was an option to completely disable the generation of full-size (zoomed) previews, as these seem to eat up a huge amount of memory (far more than non-zoomed previews). In my tests, opening one zoomed image (thereby generating previews for 5 images) used 150mb of additional memory, meaning 3-4 of these zoomed-previews could easily wipe out a 768mb RAM cache.

I believe this feature would enable PM to become more useful in the field, where working speed and battery life is important.

Thanks
Ben

Netbook System
Windows 7 starter, Photo Mechanic 4.6.2.1, 2GB RAM
RAM cache: 768mb, Disk Cache: 1024mb

[Kirk Baker]

Ben,

I believe this may help Photo Mechanic become much more responsive with under-powered CPUs, such as those used in netbooks. Slow CPUs tend to take a long time  building previews and, as only 5 previews are generated at any one time, this is not helpful when trying to scroll quickly through tens or hundreds of images.

Could Photo Mechanic have an option to automatically build non-zoomed previews for all images on ingest, and possibly also as a command to run on the current folder? This would mean in the field, I could ingest 30 images at a time, and let the netbook automatically build previews for those until I'm ready to scroll through and process them. It could be configured to fill up the ram cache, replacing old cached items.

While it would be possible to pre-generate larger previews in advance of using the Preview window, there are a couple of issues.  One, you can show/hide various parts of the Preview interface, thus changing the size of the previews dynamically (so there is no one-size fits all scenario).  Second, unless those pre-generated previews are preloaded and managed extremely well, you're still going to take a hit when they have to be loaded from disk as JPEGs, decoded, optionally color-managed and sharpened.

How fast do you expect to 'scroll' through your images on a Netbook?

-Kirk

[ba1212]

Thanks for the quick reply, Kirk.

In answer to your question, even moving through images at a normal speed is quite painful, due to the slow CPU taking a number of seconds to render each image. You can imagine how frustrating that gets, so I thought the preview idea was a way around it.

I understand if it's too complicated, but my netbook is just so perfect (12 hours battery life etc) so I'd love to find a solution to this problem!

Thanks again.
Ben
 

[ba1212]

Hi

It seems turning off colour management in PM greatly improves the preview generation speed, making it far more usable on netbooks.

Kirk - can you confirm if that's true? If so, my problem is solved 

Ben

[Kirk Baker]

Ben,

It seems turning off colour management in PM greatly improves the preview generation speed, making it far more usable on netbooks.

Kirk - can you confirm if that's true? If so, my problem is solved 

In general, color management adds about 25% more time to generating images.

-Kirk

[vAfotoriporter]

Thanks for the quick reply, Kirk.

In answer to your question, even moving through images at a normal speed is quite painful, due to the slow CPU taking a number of seconds to render each image. You can imagine how frustrating that gets, so I thought the preview idea was a way around it.

I understand if it's too complicated, but my netbook is just so perfect (12 hours battery life etc) so I'd love to find a solution to this problem!

Thanks again.
Ben

I had an Asus EeePC with 1,6 GHz Atom CPU and 512 or 1GB RAM I think. PM was not in a rush but it was manageable. LightRoom was a bit slower but with only the necessary photos imported it was useable.

Now I changed it to a MacBook Air 11" with 1,6GHz and 4GB RAM. It is in speed almost comparable to my 2,4GHz MacBook Pro. I don't really have any issues with it - especially not with PM.