How do I convert old .ithmb files from an iPhone into JPEGs to recover my photos?

Old Toad wrote: …They are not normal image files. but files created to show a number of images on a mobile Apple device.

I found some ithumb files and tried them in GraphicConvereter, but the result was garbage. There's probably no hope…

An .ithmb file is a photo thumbnail file created by Apple devices like the iPhone, iPad, and iPod, containing a collection of images in different sizes for quick viewing. These files are created to organize and display photos efficiently on these devices, and they are not a standard image format, so they typically need special software to be viewed or converted to a more common format like JPEG. 

o view a .thumb file, you will likely need to use a dedicated viewer, as .thumb files are hidden cache files containing thumbnail images. You can find viewers like Thumbcache Viewer or Thumbs Viewer online that are designed to extract and display the images from these files. 

They are not normal image files. but files created to show a number of images on a mobile Apple device.

Richard.Taylor wrote:

I found some ithumb files and tried them in GraphicConvereter, but the result was garbage. There's probably no hope…

...or to nag GC author about this. I also tried this with GC but decided to Let It Be because I've nagged him more than enough for personally more important features or issues like movie metadata, and .avif, .webp, Google Photos .json metadata etc. Because of that, I have to use exiftool for those tasks only in some edge cases. He is very responsive to fix things like this, if possible. After all, GC is THE "Swiss Army Knife" for obscure image formats. FWIW also Photoshop fails to open Photos generated .ithmb files.

Matti Haveri wrote: I've nagged him more than enough for personally more important features

There are many times I have been in touch with Thorsten Lemke-- he is always responsive! I use  GraphicConverter every day!