[Pix2Pix] Add utility function (#2385)

* [Pix2Pix] Add utility function

* improve

* update

* Apply suggestions from code review

* uP

* Update src/diffusers/pipelines/stable_diffusion/pipeline_stable_diffusion_pix2pix_zero.py

src/diffusers/pipelines/stable_diffusion/pipeline_stable_diffusion_pix2pix_zero.py

@@ -542,6 +542,26 @@ class StableDiffusionPix2PixZeroPipeline(DiffusionPipeline):
         """Constructs the edit direction to steer the image generation process semantically."""
         return (embs_target.mean(0) - embs_source.mean(0)).unsqueeze(0)
 
+    @torch.no_grad()
+    def get_embeds(self, prompt: List[str], batch_size: int = 16) -> torch.FloatTensor:
+        num_prompts = len(prompt)
+        embeds = []
+        for i in range(0, num_prompts, batch_size):
+            prompt_slice = prompt[i : i + batch_size]
+
+            input_ids = self.tokenizer(
+                prompt_slice,
+                padding="max_length",
+                max_length=self.tokenizer.model_max_length,
+                truncation=True,
+                return_tensors="pt",
+            ).input_ids
+
+            input_ids = input_ids.to(self.text_encoder.device)
+            embeds.append(self.text_encoder(input_ids)[0])
+
+        return torch.cat(embeds, dim=0).mean(0)[None]
+
     @torch.no_grad()
     @replace_example_docstring(EXAMPLE_DOC_STRING)
     def __call__(