When creating an UIImage with corrupt/incomplete JPEG data, the console will print out
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Depends on how you are getting the data etc. Maybe this is what you are looking for: iphone-corrupt-jpeg-data-for-image-received-over-http
A simple way to check if the JPEG data is complete or not is to check the first and last two bytes for FF D8 and FF D9 respectively. Those two bytes identify the start and end of a JPEG file respectively.