![]() offset (to first image from beginning of file) There are three settings which must be set: It will very likely look like total garbage at first. Notice that as soon as you open an ithmb file, a sample image appears. The next step is to figure out the settings that decode a correct image. Start by opening an ithmb file either from your iPod (which should appear as an external disk on your Desktop) or from an ithmb file on your mac if you have copied one from your iPod to your mac. When the program is launched you are presented with the Work Bench, which is used to find the proper settings for your ithmb files. Converting the images from the ithmb encoding (in most cases some version of YUV, although in some cases variations on RGB) to a more computer friendly encoding such as 32-bit RGB is a fairly slow process. ![]() Opening a large library will take a long time. Therefore, you only need to determine the settings for a single file of a given four-digit prefix to find the settings for all files with that prefix. ![]() All files with a given four-digit prefix store images of the same resolution and encoding method (I'm *pretty* sure about this). Note that your ithmb file collection probably consists of a set of multiple files, each starting with a four-digit prefix. The encoding for each image is relatively complicated and you don't need to understand it to use this program. If a photo library is large enough it will spill over into sequentially numbered files. The ithmb file format requires converting each image to a particular encoding that is tailored to the display format (either the iPod's screen or an external TV) and then concatenating all of the images in the library into a single file that may span hundreds of Megabytes. This is because the highest resolution images are preprocessed for display on NTSC video devices (a typical TV for example), on which 720x480 is an industry standard. ![]() Note that the resolutions that are preprocessed for one model of iPod tend to differ from those preprocessed for another, although the highest preprocessed resolution (720x480) is fairly consistent across iPod lines. For example, the resolutions that are preprocessed by iTunes for a 4th generation iPod are:Ĥ2x30: used in the five by five thumbnail display on the iPod's screenġ30x88: not sure what this is used for, possibly on the iPod's screen during displaying on an external video deviceĢ20x176: used for displaying images on the iPod's screenħ20x480: used for displaying images on a video device (TV)Īlternatively, a sixth generation iPod stores only three resolutions (I think): 64圆4, 320x240, and 720x480. In fact, the iPod uses many different resolutions for various situations, and each resolution is stored independently on the iPod, ready for immediate use whenever the need arises. These images are preprocessed by iTunes during syncing so that the iPod does not have to perform any resizing on the fly. The other photo format used by the iPod is intended for presenting photos on the iPod's own screen or for presenting photos on a video device (TV) attached to the iPod. They are intended solely for storing and transferring images on the iPod as an external storage device. Full resolution photos cannot be viewed on the iPod's display or on a video device attached to the iPod. This can be useful for transferring photos from one computer to another or simply for having constant access to a library of high-resolution images without the need to carry a computer or external hard-drive around with you all the time. Such files are direct transfers of original images to the iPod such that the image is preserved at its high resolution, probably many Megapixels. The easiest to understand is the "full resolution" photo format. The iPod stores images in two major formats. These files can be found in the /Photos/Thumbs/ directory of an iPod that has been synced to contain a photo library. This program serves a very specific and minimally useful purpose, to provide access to the Apple iPod's elusive ithmb photo library. However, do not complain to me or anyone else that the program is difficult or confusing until you have resorted to the utter humility of actually reading this file in its entirety!.then you can complain about it. If you're the kind of person who skims the README and docs looking for gold nuggets of useful information, then skip down to HOW TO USE IT, or even down to KNOWN ENCODINGS OF HIGHEST RESOLUTION IMAGES if you feel so inclined. If you're the kind of person who never reads the directions, then go mess with the program to your heart's content and come back here if and when you get stuck.
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