Resize PSB file and Generate Thumbnail programmatically

Hi there,

I'm looking for a way to resize the PSB file and make thumbnail image. The content I'm working with is around 30GB, explored the photoshop API, but seems like PSB is not supported. So wondering if anyone has any experiences on this problem statement. I'm not looking for solutions from the app approach, only looking for solution from API or SDK approaches. Any help or idea would be appreciated.