Text2video zero refinements (#3070)

* fix progress bar issue in pipeline_text_to_video_zero.py. Copy scheduler after first backward

* fix tensor loading in test_text_to_video_zero.py

* make style && make quality

src/diffusers/pipelines/text_to_video_synthesis/pipeline_text_to_video_zero.py

@@ -1,3 +1,4 @@
+import copy
 from dataclasses import dataclass
 from typing import Callable, List, Optional, Union
 
@@ -56,8 +57,8 @@ class CrossFrameAttnProcessor:
         is_cross_attention = encoder_hidden_states is not None
         if encoder_hidden_states is None:
             encoder_hidden_states = hidden_states
-        elif attn.cross_attention_norm:
-            encoder_hidden_states = attn.norm_cross(encoder_hidden_states)
+        elif attn.norm_cross:
+            encoder_hidden_states = attn.norm_encoder_hidden_states(encoder_hidden_states)
 
         key = attn.to_k(encoder_hidden_states)
         value = attn.to_v(encoder_hidden_states)
@@ -285,7 +286,8 @@ class TextToVideoZeroPipeline(StableDiffusionPipeline):
             latents: latents of backward process output at time timesteps[-1]
         """
         do_classifier_free_guidance = guidance_scale > 1.0
-        with self.progress_bar(total=len(timesteps)) as progress_bar:
+        num_steps = (len(timesteps) - num_warmup_steps) // self.scheduler.order
+        with self.progress_bar(total=num_steps) as progress_bar:
             for i, t in enumerate(timesteps):
                 # expand the latents if we are doing classifier free guidance
                 latent_model_input = torch.cat([latents] * 2) if do_classifier_free_guidance else latents
@@ -465,6 +467,7 @@ class TextToVideoZeroPipeline(StableDiffusionPipeline):
             extra_step_kwargs=extra_step_kwargs,
             num_warmup_steps=num_warmup_steps,
         )
+        scheduler_copy = copy.deepcopy(self.scheduler)
 
         # Perform the second backward process up to time T_0
         x_1_t0 = self.backward_loop(
@@ -475,7 +478,7 @@ class TextToVideoZeroPipeline(StableDiffusionPipeline):
             callback=callback,
             callback_steps=callback_steps,
             extra_step_kwargs=extra_step_kwargs,
-            num_warmup_steps=num_warmup_steps,
+            num_warmup_steps=0,
         )
 
         # Propagate first frame latents at time T_0 to remaining frames
@@ -502,7 +505,7 @@ class TextToVideoZeroPipeline(StableDiffusionPipeline):
         b, l, d = prompt_embeds.size()
         prompt_embeds = prompt_embeds[:, None].repeat(1, video_length, 1, 1).reshape(b * video_length, l, d)
 
-        self.scheduler.set_timesteps(num_inference_steps, device=device)
+        self.scheduler = scheduler_copy
         x_1k_0 = self.backward_loop(
             timesteps=timesteps[-t1 - 1 :],
             prompt_embeds=prompt_embeds,
@@ -511,7 +514,7 @@ class TextToVideoZeroPipeline(StableDiffusionPipeline):
             callback=callback,
             callback_steps=callback_steps,
             extra_step_kwargs=extra_step_kwargs,
-            num_warmup_steps=num_warmup_steps,
+            num_warmup_steps=0,
         )
         latents = x_1k_0
 

src/diffusers/utils/__init__.py

@@ -86,6 +86,7 @@ if is_torch_available():
         load_hf_numpy,
         load_image,
         load_numpy,
+        load_pt,
         nightly,
         parse_flag_from_env,
         print_tensor_test,

tests/pipelines/text_to_video/test_text_to_video_zero.py

@@ -18,7 +18,7 @@ import unittest
 import torch
 
 from diffusers import DDIMScheduler, TextToVideoZeroPipeline
-from diffusers.utils import require_torch_gpu, slow
+from diffusers.utils import load_pt, require_torch_gpu, slow
 
 from ...test_pipelines_common import assert_mean_pixel_difference
 
@@ -35,8 +35,8 @@ class TextToVideoZeroPipelineSlowTests(unittest.TestCase):
         prompt = "A bear is playing a guitar on Times Square"
         result = pipe(prompt=prompt, generator=generator).images
 
-        expected_result = torch.load(
-            "https://huggingface.co/datasets/hf-internal-testing/diffusers-images/tree/main/text-to-video/A bear is playing a guitar on Times Square.pt"
+        expected_result = load_pt(
+            "https://huggingface.co/datasets/hf-internal-testing/diffusers-images/resolve/main/text-to-video/A bear is playing a guitar on Times Square.pt"
         )
 
         assert_mean_pixel_difference(result, expected_result)