transform the reference image. Must be between 0 and 1. image is used as a
starting point and more noise is added the higher the strength. The number of denoising steps depends
on the amount of noise initially added. When strength is 1, added noise is maximum and the denoising
process runs for the full number of iterations specified in num_inference_steps. A value of 1
essentially ignores image.   num_inference_steps (int, optional, defaults to