Merge pull request kohya-ss#1433 from millie-v/sample-image-without-cuda

Generate sample images without having CUDA (such as on Macs)

Author: kohya-ss

library/train_util.py

@@ -5404,7 +5404,7 @@ def sample_images_common(
     clean_memory_on_device(accelerator.device)
 
     torch.set_rng_state(rng_state)
-    if cuda_rng_state is not None:
+    if torch.cuda.is_available() and cuda_rng_state is not None:
         torch.cuda.set_rng_state(cuda_rng_state)
     vae.to(org_vae_device)
 
@@ -5438,11 +5438,13 @@ def sample_image_inference(
 
     if seed is not None:
         torch.manual_seed(seed)
-        torch.cuda.manual_seed(seed)
+        if torch.cuda.is_available():
+            torch.cuda.manual_seed(seed)
     else:
         # True random sample image generation
         torch.seed()
-        torch.cuda.seed()
+        if torch.cuda.is_available():
+            torch.cuda.seed()
 
     scheduler = get_my_scheduler(
         sample_sampler=sampler_name,
@@ -5477,8 +5479,9 @@ def sample_image_inference(
             controlnet_image=controlnet_image,
         )
 
-    with torch.cuda.device(torch.cuda.current_device()):
-        torch.cuda.empty_cache()
+    if torch.cuda.is_available():
+        with torch.cuda.device(torch.cuda.current_device()):
+            torch.cuda.empty_cache()
 
     image = pipeline.latents_to_image(latents)[0]