Photo Cache (.itmb) taking up too much space on iPhone

[jrock325]

I've optimized my photos so they won't take up too much space on my iPhone. I have 94 photos that only take up 6 mb total. But when I look in iTunes it says my photos are taking up 60 mb!
When looking in my picture dir on my PC (XP) the iPod Photo Cache dir has 50 directories in it (F00 - F50) each about 1 mb. That's 50 mb of .ithmb files!
Why do I have so many F** directories? Do I need all of them? and why are they so large when compared to my actual photos?

 

[iphoneuser]

Same.

I have 150 images @ the iPhone's native resolution of 480x320 taking up 7.7mb of hd space, but the cache is using over ten times that size, 96.2mb. Is this a bug, or is the iPhone's photo management just wildly inefficient? Aside from the fact that I cannot fathom where all that extra data is being used (read: wasted), I feel like I wasted my time optimizing all those images to fit snugly on the iPhone.

Is there an ideal resolution photos should be cropped to so that the photo tool on the iPhone doesn't have to waste so much extra data generating inefficient duplicates of my photos? I figured cropping to its native resolution would have been ideal, but apparently not. If the "zoom" feature isn't actually zooming into photos, but rather switching you to a higher resolution version, that is basically the resolution I want to know so that I can re-crop all my photos. This way the iPhone will only have to generate the smaller versions for thumbnails, etc. And if anyone knows a way to manually provide the iPhone with all sizes needed for each photo (so I have complete control for filesize concerns), that would be even better.

 

[G4R2]

Unfortunately this is the way the iPhone and other iPods store and display images. Regardless of the size of the original file, iPhoto will convert the image into an .ithmb file which will frequently be both larger and of lower resolution than the original. Even if you select to store the original full resolution image on the device it seems that the iPod/iPhone will still use the .ithmb file to display the image and will simply store both files on the device.

I suspect there must be some technical rationale for doing this, maybe the way a relic of the way the Portalplayer chips on 5G iPods display images which probably favors a file format that is quick to display as opposed to being full resolution or compact. It's frustrating with the iPhone because it seems the iPhone can display .jpgs and PDFs without conversion.