Problems with CICoreMLModelFilter

I'm trying to integrate my neural style transfer models into Core Image using the new

CICoreMLModelFilter

. It is working, however, I noticed a few problems with the filter:

• Aside from Session 719 of this year's WWDC it's not mentionend at all in any piece of documentation.
• It leaks a lot of memory with every call to

  outputImage

  . I dug a little deeper into the Memory Graph and found that a new

  CIPredictionModel

  along with a heavy

  IOSurface

  and various other objects is created with each call and never released.
• I just uses scale-to-fit on the input image to match the MLModel's input size—not the smart scaling, cropping and resizing that Vision does when working with MLModels.
• It can't handle flexible model input sizes. Even when specifying allowed ranges for model input dimensions, the filter will always scale the input to the model's designated input size.

As an alternative I wrote my own

CIImageProcessorKernel

with just a few lines of code that wraps a Core ML model and does the same without the issues mentioned above.

I wish Apple would provide any documentation on how to use

CICoreMLModelFilter

properly.