Merge branch 'gabrielrotbart-fix_img2img_m1' into main

This may improve the black image problem when using img2img with some
samplers on M1 hardware.

Author: lstein

ldm/simplet2i.py

@@ -280,7 +280,14 @@ def process_image(image,seed):
         ), 'can only work with strength in [0.0, 1.0]'
 
         width, height, _ = self._resolution_check(width, height, log=True)
-        scope = autocast if self.precision == 'autocast' else nullcontext
+
+        # TODO: - Check if this is still necessary to run on M1 devices.
+        #       - Move code into ldm.dream.devices to live alongside other
+        #         special-hardware casing code.
+        if self.precision == 'autocast' and torch.cuda.is_available():
+            scope = autocast
+        else:
+            scope = nullcontext
 
         if sampler_name and (sampler_name != self.sampler_name):
             self.sampler_name = sampler_name