Q: I am considering buying an iPod touch, but am hesitating between the 8GB and 16GB models. I have about 6GB of music that I would like to carry on my iPod, plus some photos. To help me decide if 8GB would be enough, it would help to know how much space is required to store a photo on the iPod touch. Is the original jpeg file transferred to the iPod, or an “optimized”, reduced in size version? If it is a reduced version, what size is a typical photo? How much storage would be required to hold 1000 photos?
A: In much the same way as photo transfer has always worked on the other iPod models, iTunes reduces/optimizes the photo size when transferring it to the iPod touch (and the iPhone). This is to make the best use of available storage, as well as to offload some of the photo processing from the device itself, since it only needs to display a pre-optimized version of the photo.
The iPhone and iPod touch actually store four resolutions of each photo: Two for the different thumbnail views, one pre-resized for sending out via e-mail, and one in the maximum 640×480 resolution for viewing on the iPod touch or via the TV output. Despite the fact that the iPod touch screen is only 320×480, the zoom and TV output features make it necessary to store a higher-resolution version of the image.
The bottom line of all of this is that each image stored on your iPod will take approximately 676,192 bytes, or 660 KB, regardless of the size of the original photo (lower-resolution photos are still scaled up to these sizes).
Unlike the fifth-generation iPod or iPod classic, the iPod touch does not have a “Disk Mode” and there is therefore no option to store full resolution photos (as they cannot be manually retrieved from the device).
For more information, you may want to take a look at our forum thread, Photo Storage on the iPod and iPhone – The Gory Details, which has recently been updated for the iPhone and iPod touch.