Please try extracting the features separately from training. If you can't extract features for all of your images in memory, try instead to write the extracted features to disk. Then use the saved features for training. This has the added advantage that you will only need to do this once, and can then train multiple models, or one model over multiple iterations. For reference please see the WWDC session and the ImageFeaturePrint documentation.. Thanks for reporting the issue, we are looking into it.