Ensure validation image RGB not RGBA (#2945)

* ensure validation image RGB not RGBA

* ensure validation image RGB not RGBA

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Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>

examples/controlnet/train_controlnet.py

@@ -106,7 +106,7 @@ def log_validation(vae, text_encoder, tokenizer, unet, controlnet, args, acceler
     image_logs = []
 
     for validation_prompt, validation_image in zip(validation_prompts, validation_images):
-        validation_image = Image.open(validation_image)
+        validation_image = Image.open(validation_image).convert('RGB')
 
         images = []
 

examples/controlnet/train_controlnet_flax.py

@@ -110,7 +110,7 @@ def log_validation(controlnet, controlnet_params, tokenizer, args, rng, weight_d
         prompt_ids = pipeline.prepare_text_inputs(prompts)
         prompt_ids = shard(prompt_ids)
 
-        validation_image = Image.open(validation_image)
+        validation_image = Image.open(validation_image).convert('RGB')
         processed_image = pipeline.prepare_image_inputs(num_samples * [validation_image])
         processed_image = shard(processed_image)
         images = pipeline(