Add TensorRT SD/txt2img Community Pipeline to diffusers along with TensorRT utils (#2974)

* Add SD/txt2img Community Pipeline to diffusers along with TensorRT utils
Signed-off-by: Asfiya Baig <asfiyab@nvidia.com>

* update installation command
Signed-off-by: Asfiya Baig <asfiyab@nvidia.com>

* update tensorrt installation
Signed-off-by: Asfiya Baig <asfiyab@nvidia.com>

* changes
1. Update setting of cache directory
2. Address comments: merge utils and pipeline code.
3. Address comments: Add section in README
Signed-off-by: Asfiya Baig <asfiyab@nvidia.com>

* apply make style
Signed-off-by: Asfiya Baig <asfiyab@nvidia.com>

---------
Signed-off-by: Asfiya Baig <asfiyab@nvidia.com>
Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>

examples/community/README.md

@@ -31,7 +31,7 @@ MagicMix | Diffusion Pipeline for semantic mixing of an image and a text prompt
 | UnCLIP Image Interpolation Pipeline | Diffusion Pipeline that allows passing two images/image_embeddings and produces images while interpolating between their image-embeddings | [UnCLIP Image Interpolation Pipeline](#unclip-image-interpolation-pipeline)                   | -                                                                                                                                                                                                                  | [Naga Sai Abhinay Devarinti](https://github.com/Abhinay1997/) | 
 | DDIM Noise Comparative Analysis Pipeline | Investigating how the diffusion models learn visual concepts from each noise level (which is a contribution of [P2 weighting (CVPR 2022)](https://arxiv.org/abs/2204.00227)) | [DDIM Noise Comparative Analysis Pipeline](#ddim-noise-comparative-analysis-pipeline) | - |[Aengus (Duc-Anh)](https://github.com/aengusng8) |
 | CLIP Guided Img2Img Stable Diffusion Pipeline | Doing CLIP guidance for image to image generation with Stable Diffusion | [CLIP Guided Img2Img Stable Diffusion](#clip-guided-img2img-stable-diffusion) | - | [Nipun Jindal](https://github.com/nipunjindal/) | 
-
+| TensorRT Stable Diffusion Pipeline | Accelerates the Stable Diffusion Text2Image Pipeline using TensorRT | [TensorRT Stable Diffusion Pipeline](#tensorrt-text2image-stable-diffusion-pipeline) | - |[Asfiya Baig](https://github.com/asfiyab-nvidia) |
 
 
 To load a custom pipeline you just need to pass the `custom_pipeline` argument to `DiffusionPipeline`, as one of the files in `diffusers/examples/community`. Feel free to send a PR with your own pipelines, we will merge them quickly.
@@ -1130,3 +1130,34 @@ Init Image
 Output Image
 
 ![img2img_clip_guidance](https://huggingface.co/datasets/njindal/images/resolve/main/clip_guided_img2img.jpg)
+
+### TensorRT Text2Image Stable Diffusion Pipeline
+
+The TensorRT Pipeline can be used to accelerate the Text2Image Stable Diffusion Inference run.
+
+NOTE: The ONNX conversions and TensorRT engine build may take up to 30 minutes.
+
+```python
+import torch
+from diffusers import DDIMScheduler
+from diffusers.pipelines.stable_diffusion import StableDiffusionPipeline
+
+# Use the DDIMScheduler scheduler here instead
+scheduler = DDIMScheduler.from_pretrained("stabilityai/stable-diffusion-2-1",
+                                            subfolder="scheduler")
+
+pipe = StableDiffusionPipeline.from_pretrained("stabilityai/stable-diffusion-2-1",
+                                                custom_pipeline="stable_diffusion_tensorrt_txt2img",
+                                                revision='fp16',
+                                                torch_dtype=torch.float16,
+                                                scheduler=scheduler,)
+
+# re-use cached folder to save ONNX models and TensorRT Engines
+pipe.set_cached_folder("stabilityai/stable-diffusion-2-1", revision='fp16',)
+
+pipe = pipe.to("cuda")
+
+prompt = "a beautiful photograph of Mt. Fuji during cherry blossom"
+image = pipe(prompt).images[0]
+image.save('tensorrt_mt_fuji.png')
+```

examples/community/stable_diffusion_tensorrt_txt2img.py

+#
+# Copyright 2023 The HuggingFace Inc. team.
+# SPDX-FileCopyrightText: Copyright (c) 1993-2023 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import gc
+import os
+from collections import OrderedDict
+from copy import copy
+from typing import List, Optional, Union
+
+import numpy as np
+import onnx
+import onnx_graphsurgeon as gs
+import tensorrt as trt
+import torch
+from huggingface_hub import snapshot_download
+from onnx import shape_inference
+from polygraphy import cuda
+from polygraphy.backend.common import bytes_from_path
+from polygraphy.backend.onnx.loader import fold_constants
+from polygraphy.backend.trt import (
+    CreateConfig,
+    Profile,
+    engine_from_bytes,
+    engine_from_network,
+    network_from_onnx_path,
+    save_engine,
+)
+from polygraphy.backend.trt import util as trt_util
+from transformers import CLIPFeatureExtractor, CLIPTextModel, CLIPTokenizer
+
+from diffusers.models import AutoencoderKL, UNet2DConditionModel
+from diffusers.pipelines.stable_diffusion import (
+    StableDiffusionPipeline,
+    StableDiffusionPipelineOutput,
+    StableDiffusionSafetyChecker,
+)
+from diffusers.schedulers import DDIMScheduler
+from diffusers.utils import DIFFUSERS_CACHE, logging
+
+
+"""
+Installation instructions
+python3 -m pip install --upgrade tensorrt
+python3 -m pip install --upgrade polygraphy onnx-graphsurgeon --extra-index-url https://pypi.ngc.nvidia.com
+python3 -m pip install onnxruntime
+"""
+
+TRT_LOGGER = trt.Logger(trt.Logger.ERROR)
+logger = logging.get_logger(__name__)  # pylint: disable=invalid-name
+
+# Map of numpy dtype -> torch dtype
+numpy_to_torch_dtype_dict = {
+    np.uint8: torch.uint8,
+    np.int8: torch.int8,
+    np.int16: torch.int16,
+    np.int32: torch.int32,
+    np.int64: torch.int64,
+    np.float16: torch.float16,
+    np.float32: torch.float32,
+    np.float64: torch.float64,
+    np.complex64: torch.complex64,
+    np.complex128: torch.complex128,
+}
+if np.version.full_version >= "1.24.0":
+    numpy_to_torch_dtype_dict[np.bool_] = torch.bool
+else:
+    numpy_to_torch_dtype_dict[np.bool] = torch.bool
+
+# Map of torch dtype -> numpy dtype
+torch_to_numpy_dtype_dict = {value: key for (key, value) in numpy_to_torch_dtype_dict.items()}
+
+
+def device_view(t):
+    return cuda.DeviceView(ptr=t.data_ptr(), shape=t.shape, dtype=torch_to_numpy_dtype_dict[t.dtype])
+
+
+class Engine:
+    def __init__(self, engine_path):
+        self.engine_path = engine_path
+        self.engine = None
+        self.context = None
+        self.buffers = OrderedDict()
+        self.tensors = OrderedDict()
+
+    def __del__(self):
+        [buf.free() for buf in self.buffers.values() if isinstance(buf, cuda.DeviceArray)]
+        del self.engine
+        del self.context
+        del self.buffers
+        del self.tensors
+
+    def build(
+        self,
+        onnx_path,
+        fp16,
+        input_profile=None,
+        enable_preview=False,
+        enable_all_tactics=False,
+        timing_cache=None,
+        workspace_size=0,
+    ):
+        logger.warning(f"Building TensorRT engine for {onnx_path}: {self.engine_path}")
+        p = Profile()
+        if input_profile:
+            for name, dims in input_profile.items():
+                assert len(dims) == 3
+                p.add(name, min=dims[0], opt=dims[1], max=dims[2])
+
+        config_kwargs = {}
+
+        config_kwargs["preview_features"] = [trt.PreviewFeature.DISABLE_EXTERNAL_TACTIC_SOURCES_FOR_CORE_0805]
+        if enable_preview:
+            # Faster dynamic shapes made optional since it increases engine build time.
+            config_kwargs["preview_features"].append(trt.PreviewFeature.FASTER_DYNAMIC_SHAPES_0805)
+        if workspace_size > 0:
+            config_kwargs["memory_pool_limits"] = {trt.MemoryPoolType.WORKSPACE: workspace_size}
+        if not enable_all_tactics:
+            config_kwargs["tactic_sources"] = []
+
+        engine = engine_from_network(
+            network_from_onnx_path(onnx_path),
+            config=CreateConfig(fp16=fp16, profiles=[p], load_timing_cache=timing_cache, **config_kwargs),
+            save_timing_cache=timing_cache,
+        )
+        save_engine(engine, path=self.engine_path)
+
+    def load(self):
+        logger.warning(f"Loading TensorRT engine: {self.engine_path}")
+        self.engine = engine_from_bytes(bytes_from_path(self.engine_path))
+
+    def activate(self):
+        self.context = self.engine.create_execution_context()
+
+    def allocate_buffers(self, shape_dict=None, device="cuda"):
+        for idx in range(trt_util.get_bindings_per_profile(self.engine)):
+            binding = self.engine[idx]
+            if shape_dict and binding in shape_dict:
+                shape = shape_dict[binding]
+            else:
+                shape = self.engine.get_binding_shape(binding)
+            dtype = trt.nptype(self.engine.get_binding_dtype(binding))
+            if self.engine.binding_is_input(binding):
+                self.context.set_binding_shape(idx, shape)
+            tensor = torch.empty(tuple(shape), dtype=numpy_to_torch_dtype_dict[dtype]).to(device=device)
+            self.tensors[binding] = tensor
+            self.buffers[binding] = cuda.DeviceView(ptr=tensor.data_ptr(), shape=shape, dtype=dtype)
+
+    def infer(self, feed_dict, stream):
+        start_binding, end_binding = trt_util.get_active_profile_bindings(self.context)
+        # shallow copy of ordered dict
+        device_buffers = copy(self.buffers)
+        for name, buf in feed_dict.items():
+            assert isinstance(buf, cuda.DeviceView)
+            device_buffers[name] = buf
+        bindings = [0] * start_binding + [buf.ptr for buf in device_buffers.values()]
+        noerror = self.context.execute_async_v2(bindings=bindings, stream_handle=stream.ptr)
+        if not noerror:
+            raise ValueError("ERROR: inference failed.")
+
+        return self.tensors
+
+
+class Optimizer:
+    def __init__(self, onnx_graph):
+        self.graph = gs.import_onnx(onnx_graph)
+
+    def cleanup(self, return_onnx=False):
+        self.graph.cleanup().toposort()
+        if return_onnx:
+            return gs.export_onnx(self.graph)
+
+    def select_outputs(self, keep, names=None):
+        self.graph.outputs = [self.graph.outputs[o] for o in keep]
+        if names:
+            for i, name in enumerate(names):
+                self.graph.outputs[i].name = name
+
+    def fold_constants(self, return_onnx=False):
+        onnx_graph = fold_constants(gs.export_onnx(self.graph), allow_onnxruntime_shape_inference=True)
+        self.graph = gs.import_onnx(onnx_graph)
+        if return_onnx:
+            return onnx_graph
+
+    def infer_shapes(self, return_onnx=False):
+        onnx_graph = gs.export_onnx(self.graph)
+        if onnx_graph.ByteSize() > 2147483648:
+            raise TypeError("ERROR: model size exceeds supported 2GB limit")
+        else:
+            onnx_graph = shape_inference.infer_shapes(onnx_graph)
+
+        self.graph = gs.import_onnx(onnx_graph)
+        if return_onnx:
+            return onnx_graph
+
+
+class BaseModel:
+    def __init__(self, model, fp16=False, device="cuda", max_batch_size=16, embedding_dim=768, text_maxlen=77):
+        self.model = model
+        self.name = "SD Model"
+        self.fp16 = fp16
+        self.device = device
+
+        self.min_batch = 1
+        self.max_batch = max_batch_size
+        self.min_image_shape = 256  # min image resolution: 256x256
+        self.max_image_shape = 1024  # max image resolution: 1024x1024
+        self.min_latent_shape = self.min_image_shape // 8
+        self.max_latent_shape = self.max_image_shape // 8
+
+        self.embedding_dim = embedding_dim
+        self.text_maxlen = text_maxlen
+
+    def get_model(self):
+        return self.model
+
+    def get_input_names(self):
+        pass
+
+    def get_output_names(self):
+        pass
+
+    def get_dynamic_axes(self):
+        return None
+
+    def get_sample_input(self, batch_size, image_height, image_width):
+        pass
+
+    def get_input_profile(self, batch_size, image_height, image_width, static_batch, static_shape):
+        return None
+
+    def get_shape_dict(self, batch_size, image_height, image_width):
+        return None
+
+    def optimize(self, onnx_graph):
+        opt = Optimizer(onnx_graph)
+        opt.cleanup()
+        opt.fold_constants()
+        opt.infer_shapes()
+        onnx_opt_graph = opt.cleanup(return_onnx=True)
+        return onnx_opt_graph
+
+    def check_dims(self, batch_size, image_height, image_width):
+        assert batch_size >= self.min_batch and batch_size <= self.max_batch
+        assert image_height % 8 == 0 or image_width % 8 == 0
+        latent_height = image_height // 8
+        latent_width = image_width // 8
+        assert latent_height >= self.min_latent_shape and latent_height <= self.max_latent_shape
+        assert latent_width >= self.min_latent_shape and latent_width <= self.max_latent_shape
+        return (latent_height, latent_width)
+
+    def get_minmax_dims(self, batch_size, image_height, image_width, static_batch, static_shape):
+        min_batch = batch_size if static_batch else self.min_batch
+        max_batch = batch_size if static_batch else self.max_batch
+        latent_height = image_height // 8
+        latent_width = image_width // 8
+        min_image_height = image_height if static_shape else self.min_image_shape
+        max_image_height = image_height if static_shape else self.max_image_shape
+        min_image_width = image_width if static_shape else self.min_image_shape
+        max_image_width = image_width if static_shape else self.max_image_shape
+        min_latent_height = latent_height if static_shape else self.min_latent_shape
+        max_latent_height = latent_height if static_shape else self.max_latent_shape
+        min_latent_width = latent_width if static_shape else self.min_latent_shape
+        max_latent_width = latent_width if static_shape else self.max_latent_shape
+        return (
+            min_batch,
+            max_batch,
+            min_image_height,
+            max_image_height,
+            min_image_width,
+            max_image_width,
+            min_latent_height,
+            max_latent_height,
+            min_latent_width,
+            max_latent_width,
+        )
+
+
+def getOnnxPath(model_name, onnx_dir, opt=True):
+    return os.path.join(onnx_dir, model_name + (".opt" if opt else "") + ".onnx")
+
+
+def getEnginePath(model_name, engine_dir):
+    return os.path.join(engine_dir, model_name + ".plan")
+
+
+def build_engines(
+    models: dict,
+    engine_dir,
+    onnx_dir,
+    onnx_opset,
+    opt_image_height,
+    opt_image_width,
+    opt_batch_size=1,
+    force_engine_rebuild=False,
+    static_batch=False,
+    static_shape=True,
+    enable_preview=False,
+    enable_all_tactics=False,
+    timing_cache=None,
+    max_workspace_size=0,
+):
+    built_engines = {}
+    if not os.path.isdir(onnx_dir):
+        os.makedirs(onnx_dir)
+    if not os.path.isdir(engine_dir):
+        os.makedirs(engine_dir)
+
+    # Export models to ONNX
+    for model_name, model_obj in models.items():
+        engine_path = getEnginePath(model_name, engine_dir)
+        if force_engine_rebuild or not os.path.exists(engine_path):
+            logger.warning("Building Engines...")
+            logger.warning("Engine build can take a while to complete")
+            onnx_path = getOnnxPath(model_name, onnx_dir, opt=False)
+            onnx_opt_path = getOnnxPath(model_name, onnx_dir)
+            if force_engine_rebuild or not os.path.exists(onnx_opt_path):
+                if force_engine_rebuild or not os.path.exists(onnx_path):
+                    logger.warning(f"Exporting model: {onnx_path}")
+                    model = model_obj.get_model()
+                    with torch.inference_mode(), torch.autocast("cuda"):
+                        inputs = model_obj.get_sample_input(opt_batch_size, opt_image_height, opt_image_width)
+                        torch.onnx.export(
+                            model,
+                            inputs,
+                            onnx_path,
+                            export_params=True,
+                            opset_version=onnx_opset,
+                            do_constant_folding=True,
+                            input_names=model_obj.get_input_names(),
+                            output_names=model_obj.get_output_names(),
+                            dynamic_axes=model_obj.get_dynamic_axes(),
+                        )
+                    del model
+                    torch.cuda.empty_cache()
+                    gc.collect()
+                else:
+                    logger.warning(f"Found cached model: {onnx_path}")
+
+                # Optimize onnx
+                if force_engine_rebuild or not os.path.exists(onnx_opt_path):
+                    logger.warning(f"Generating optimizing model: {onnx_opt_path}")
+                    onnx_opt_graph = model_obj.optimize(onnx.load(onnx_path))
+                    onnx.save(onnx_opt_graph, onnx_opt_path)
+                else:
+                    logger.warning(f"Found cached optimized model: {onnx_opt_path} ")
+
+    # Build TensorRT engines
+    for model_name, model_obj in models.items():
+        engine_path = getEnginePath(model_name, engine_dir)
+        engine = Engine(engine_path)
+        onnx_path = getOnnxPath(model_name, onnx_dir, opt=False)
+        onnx_opt_path = getOnnxPath(model_name, onnx_dir)
+
+        if force_engine_rebuild or not os.path.exists(engine.engine_path):
+            engine.build(
+                onnx_opt_path,
+                fp16=True,
+                input_profile=model_obj.get_input_profile(
+                    opt_batch_size,
+                    opt_image_height,
+                    opt_image_width,
+                    static_batch=static_batch,
+                    static_shape=static_shape,
+                ),
+                enable_preview=enable_preview,
+                timing_cache=timing_cache,
+                workspace_size=max_workspace_size,
+            )
+        built_engines[model_name] = engine
+
+    # Load and activate TensorRT engines
+    for model_name, model_obj in models.items():
+        engine = built_engines[model_name]
+        engine.load()
+        engine.activate()
+
+    return built_engines
+
+
+def runEngine(engine, feed_dict, stream):
+    return engine.infer(feed_dict, stream)
+
+
+class CLIP(BaseModel):
+    def __init__(self, model, device, max_batch_size, embedding_dim):
+        super(CLIP, self).__init__(
+            model=model, device=device, max_batch_size=max_batch_size, embedding_dim=embedding_dim
+        )
+        self.name = "CLIP"
+
+    def get_input_names(self):
+        return ["input_ids"]
+
+    def get_output_names(self):
+        return ["text_embeddings", "pooler_output"]
+
+    def get_dynamic_axes(self):
+        return {"input_ids": {0: "B"}, "text_embeddings": {0: "B"}}
+
+    def get_input_profile(self, batch_size, image_height, image_width, static_batch, static_shape):
+        self.check_dims(batch_size, image_height, image_width)
+        min_batch, max_batch, _, _, _, _, _, _, _, _ = self.get_minmax_dims(
+            batch_size, image_height, image_width, static_batch, static_shape
+        )
+        return {
+            "input_ids": [(min_batch, self.text_maxlen), (batch_size, self.text_maxlen), (max_batch, self.text_maxlen)]
+        }
+
+    def get_shape_dict(self, batch_size, image_height, image_width):
+        self.check_dims(batch_size, image_height, image_width)
+        return {
+            "input_ids": (batch_size, self.text_maxlen),
+            "text_embeddings": (batch_size, self.text_maxlen, self.embedding_dim),
+        }
+
+    def get_sample_input(self, batch_size, image_height, image_width):
+        self.check_dims(batch_size, image_height, image_width)
+        return torch.zeros(batch_size, self.text_maxlen, dtype=torch.int32, device=self.device)
+
+    def optimize(self, onnx_graph):
+        opt = Optimizer(onnx_graph)
+        opt.select_outputs([0])  # delete graph output#1
+        opt.cleanup()
+        opt.fold_constants()
+        opt.infer_shapes()
+        opt.select_outputs([0], names=["text_embeddings"])  # rename network output
+        opt_onnx_graph = opt.cleanup(return_onnx=True)
+        return opt_onnx_graph
+
+
+def make_CLIP(model, device, max_batch_size, embedding_dim, inpaint=False):
+    return CLIP(model, device=device, max_batch_size=max_batch_size, embedding_dim=embedding_dim)
+
+
+class UNet(BaseModel):
+    def __init__(
+        self, model, fp16=False, device="cuda", max_batch_size=16, embedding_dim=768, text_maxlen=77, unet_dim=4
+    ):
+        super(UNet, self).__init__(
+            model=model,
+            fp16=fp16,
+            device=device,
+            max_batch_size=max_batch_size,
+            embedding_dim=embedding_dim,
+            text_maxlen=text_maxlen,
+        )
+        self.unet_dim = unet_dim
+        self.name = "UNet"
+
+    def get_input_names(self):
+        return ["sample", "timestep", "encoder_hidden_states"]
+
+    def get_output_names(self):
+        return ["latent"]
+
+    def get_dynamic_axes(self):
+        return {
+            "sample": {0: "2B", 2: "H", 3: "W"},
+            "encoder_hidden_states": {0: "2B"},
+            "latent": {0: "2B", 2: "H", 3: "W"},
+        }
+
+    def get_input_profile(self, batch_size, image_height, image_width, static_batch, static_shape):
+        latent_height, latent_width = self.check_dims(batch_size, image_height, image_width)
+        (
+            min_batch,
+            max_batch,
+            _,
+            _,
+            _,
+            _,
+            min_latent_height,
+            max_latent_height,
+            min_latent_width,
+            max_latent_width,
+        ) = self.get_minmax_dims(batch_size, image_height, image_width, static_batch, static_shape)
+        return {
+            "sample": [
+                (2 * min_batch, self.unet_dim, min_latent_height, min_latent_width),
+                (2 * batch_size, self.unet_dim, latent_height, latent_width),
+                (2 * max_batch, self.unet_dim, max_latent_height, max_latent_width),
+            ],
+            "encoder_hidden_states": [
+                (2 * min_batch, self.text_maxlen, self.embedding_dim),
+                (2 * batch_size, self.text_maxlen, self.embedding_dim),
+                (2 * max_batch, self.text_maxlen, self.embedding_dim),
+            ],
+        }
+
+    def get_shape_dict(self, batch_size, image_height, image_width):
+        latent_height, latent_width = self.check_dims(batch_size, image_height, image_width)
+        return {
+            "sample": (2 * batch_size, self.unet_dim, latent_height, latent_width),
+            "encoder_hidden_states": (2 * batch_size, self.text_maxlen, self.embedding_dim),
+            "latent": (2 * batch_size, 4, latent_height, latent_width),
+        }
+
+    def get_sample_input(self, batch_size, image_height, image_width):
+        latent_height, latent_width = self.check_dims(batch_size, image_height, image_width)
+        dtype = torch.float16 if self.fp16 else torch.float32
+        return (
+            torch.randn(
+                2 * batch_size, self.unet_dim, latent_height, latent_width, dtype=torch.float32, device=self.device
+            ),
+            torch.tensor([1.0], dtype=torch.float32, device=self.device),
+            torch.randn(2 * batch_size, self.text_maxlen, self.embedding_dim, dtype=dtype, device=self.device),
+        )
+
+
+def make_UNet(model, device, max_batch_size, embedding_dim, inpaint=False):
+    return UNet(
+        model,
+        fp16=True,
+        device=device,
+        max_batch_size=max_batch_size,
+        embedding_dim=embedding_dim,
+        unet_dim=(9 if inpaint else 4),
+    )
+
+
+class VAE(BaseModel):
+    def __init__(self, model, device, max_batch_size, embedding_dim):
+        super(VAE, self).__init__(
+            model=model, device=device, max_batch_size=max_batch_size, embedding_dim=embedding_dim
+        )
+        self.name = "VAE decoder"
+
+    def get_input_names(self):
+        return ["latent"]
+
+    def get_output_names(self):
+        return ["images"]
+
+    def get_dynamic_axes(self):
+        return {"latent": {0: "B", 2: "H", 3: "W"}, "images": {0: "B", 2: "8H", 3: "8W"}}
+
+    def get_input_profile(self, batch_size, image_height, image_width, static_batch, static_shape):
+        latent_height, latent_width = self.check_dims(batch_size, image_height, image_width)
+        (
+            min_batch,
+            max_batch,
+            _,
+            _,
+            _,
+            _,
+            min_latent_height,
+            max_latent_height,
+            min_latent_width,
+            max_latent_width,
+        ) = self.get_minmax_dims(batch_size, image_height, image_width, static_batch, static_shape)
+        return {
+            "latent": [
+                (min_batch, 4, min_latent_height, min_latent_width),
+                (batch_size, 4, latent_height, latent_width),
+                (max_batch, 4, max_latent_height, max_latent_width),
+            ]
+        }
+
+    def get_shape_dict(self, batch_size, image_height, image_width):
+        latent_height, latent_width = self.check_dims(batch_size, image_height, image_width)
+        return {
+            "latent": (batch_size, 4, latent_height, latent_width),
+            "images": (batch_size, 3, image_height, image_width),
+        }
+
+    def get_sample_input(self, batch_size, image_height, image_width):
+        latent_height, latent_width = self.check_dims(batch_size, image_height, image_width)
+        return torch.randn(batch_size, 4, latent_height, latent_width, dtype=torch.float32, device=self.device)
+
+
+def make_VAE(model, device, max_batch_size, embedding_dim, inpaint=False):
+    return VAE(model, device=device, max_batch_size=max_batch_size, embedding_dim=embedding_dim)
+
+
+class TensorRTStableDiffusionPipeline(StableDiffusionPipeline):
+    r"""
+    Pipeline for text-to-image generation using TensorRT accelerated Stable Diffusion.
+
+    This model inherits from [`StableDiffusionPipeline`]. Check the superclass documentation for the generic methods the
+    library implements for all the pipelines (such as downloading or saving, running on a particular device, etc.)
+
+    Args:
+        vae ([`AutoencoderKL`]):
+            Variational Auto-Encoder (VAE) Model to encode and decode images to and from latent representations.
+        text_encoder ([`CLIPTextModel`]):
+            Frozen text-encoder. Stable Diffusion uses the text portion of
+            [CLIP](https://huggingface.co/docs/transformers/model_doc/clip#transformers.CLIPTextModel), specifically
+            the [clip-vit-large-patch14](https://huggingface.co/openai/clip-vit-large-patch14) variant.
+        tokenizer (`CLIPTokenizer`):
+            Tokenizer of class
+            [CLIPTokenizer](https://huggingface.co/docs/transformers/v4.21.0/en/model_doc/clip#transformers.CLIPTokenizer).
+        unet ([`UNet2DConditionModel`]): Conditional U-Net architecture to denoise the encoded image latents.
+        scheduler ([`SchedulerMixin`]):
+            A scheduler to be used in combination with `unet` to denoise the encoded image latents. Can be one of
+            [`DDIMScheduler`], [`LMSDiscreteScheduler`], or [`PNDMScheduler`].
+        safety_checker ([`StableDiffusionSafetyChecker`]):
+            Classification module that estimates whether generated images could be considered offensive or harmful.
+            Please, refer to the [model card](https://huggingface.co/runwayml/stable-diffusion-v1-5) for details.
+        feature_extractor ([`CLIPFeatureExtractor`]):
+            Model that extracts features from generated images to be used as inputs for the `safety_checker`.
+    """
+
+    def __init__(
+        self,
+        vae: AutoencoderKL,
+        text_encoder: CLIPTextModel,
+        tokenizer: CLIPTokenizer,
+        unet: UNet2DConditionModel,
+        scheduler: DDIMScheduler,
+        safety_checker: StableDiffusionSafetyChecker,
+        feature_extractor: CLIPFeatureExtractor,
+        requires_safety_checker: bool = True,
+        stages=["clip", "unet", "vae"],
+        image_height: int = 768,
+        image_width: int = 768,
+        max_batch_size: int = 16,
+        # ONNX export parameters
+        onnx_opset: int = 17,
+        onnx_dir: str = "onnx",
+        # TensorRT engine build parameters
+        engine_dir: str = "engine",
+        force_engine_rebuild: bool = False,
+        timing_cache: str = "timing_cache",
+    ):
+        super().__init__(
+            vae, text_encoder, tokenizer, unet, scheduler, safety_checker, feature_extractor, requires_safety_checker
+        )
+
+        self.vae.forward = self.vae.decode
+
+        self.stages = stages
+        self.image_height, self.image_width = image_height, image_width
+        self.inpaint = False
+        self.onnx_opset = onnx_opset
+        self.onnx_dir = onnx_dir
+        self.engine_dir = engine_dir
+        self.force_engine_rebuild = force_engine_rebuild
+        self.timing_cache = timing_cache
+        self.build_static_batch = False
+        self.build_dynamic_shape = False
+        self.build_preview_features = False
+
+        self.max_batch_size = max_batch_size
+        # TODO: Restrict batch size to 4 for larger image dimensions as a WAR for TensorRT limitation.
+        if self.build_dynamic_shape or self.image_height > 512 or self.image_width > 512:
+            self.max_batch_size = 4
+
+        self.stream = None  # loaded in loadResources()
+        self.models = {}  # loaded in __loadModels()
+        self.engine = {}  # loaded in build_engines()
+
+    def __loadModels(self):
+        # Load pipeline models
+        self.embedding_dim = self.text_encoder.config.hidden_size
+        models_args = {
+            "device": self.torch_device,
+            "max_batch_size": self.max_batch_size,
+            "embedding_dim": self.embedding_dim,
+            "inpaint": self.inpaint,
+        }
+        if "clip" in self.stages:
+            self.models["clip"] = make_CLIP(self.text_encoder, **models_args)
+        if "unet" in self.stages:
+            self.models["unet"] = make_UNet(self.unet, **models_args)
+        if "vae" in self.stages:
+            self.models["vae"] = make_VAE(self.vae, **models_args)
+
+    @classmethod
+    def set_cached_folder(cls, pretrained_model_name_or_path: Optional[Union[str, os.PathLike]], **kwargs):
+        cache_dir = kwargs.pop("cache_dir", DIFFUSERS_CACHE)
+        resume_download = kwargs.pop("resume_download", False)
+        proxies = kwargs.pop("proxies", None)
+        local_files_only = kwargs.pop("local_files_only", False)
+        use_auth_token = kwargs.pop("use_auth_token", None)
+        revision = kwargs.pop("revision", None)
+
+        cls.cached_folder = (
+            pretrained_model_name_or_path
+            if os.path.isdir(pretrained_model_name_or_path)
+            else snapshot_download(
+                pretrained_model_name_or_path,
+                cache_dir=cache_dir,
+                resume_download=resume_download,
+                proxies=proxies,
+                local_files_only=local_files_only,
+                use_auth_token=use_auth_token,
+                revision=revision,
+            )
+        )
+
+    def to(self, torch_device: Optional[Union[str, torch.device]] = None, silence_dtype_warnings: bool = False):
+        super().to(torch_device, silence_dtype_warnings)
+
+        self.onnx_dir = os.path.join(self.cached_folder, self.onnx_dir)
+        self.engine_dir = os.path.join(self.cached_folder, self.engine_dir)
+        self.timing_cache = os.path.join(self.cached_folder, self.timing_cache)
+
+        # set device
+        self.torch_device = self._execution_device
+        logger.warning(f"Running inference on device: {self.torch_device}")
+
+        # load models
+        self.__loadModels()
+
+        # build engines
+        self.engine = build_engines(
+            self.models,
+            self.engine_dir,
+            self.onnx_dir,
+            self.onnx_opset,
+            opt_image_height=self.image_height,
+            opt_image_width=self.image_width,
+            force_engine_rebuild=self.force_engine_rebuild,
+            static_batch=self.build_static_batch,
+            static_shape=not self.build_dynamic_shape,
+            enable_preview=self.build_preview_features,
+            timing_cache=self.timing_cache,
+        )
+
+        return self
+
+    def __encode_prompt(self, prompt, negative_prompt):
+        r"""
+        Encodes the prompt into text encoder hidden states.
+
+        Args:
+             prompt (`str` or `List[str]`, *optional*):
+                prompt to be encoded
+            negative_prompt (`str` or `List[str]`, *optional*):
+                The prompt or prompts not to guide the image generation. If not defined, one has to pass
+                `negative_prompt_embeds`. instead. If not defined, one has to pass `negative_prompt_embeds`. instead.
+                Ignored when not using guidance (i.e., ignored if `guidance_scale` is less than `1`).
+        """
+        # Tokenize prompt
+        text_input_ids = (
+            self.tokenizer(
+                prompt,
+                padding="max_length",
+                max_length=self.tokenizer.model_max_length,
+                truncation=True,
+                return_tensors="pt",
+            )
+            .input_ids.type(torch.int32)
+            .to(self.torch_device)
+        )
+
+        text_input_ids_inp = device_view(text_input_ids)
+        # NOTE: output tensor for CLIP must be cloned because it will be overwritten when called again for negative prompt
+        text_embeddings = runEngine(self.engine["clip"], {"input_ids": text_input_ids_inp}, self.stream)[
+            "text_embeddings"
+        ].clone()
+
+        # Tokenize negative prompt
+        uncond_input_ids = (
+            self.tokenizer(
+                negative_prompt,
+                padding="max_length",
+                max_length=self.tokenizer.model_max_length,
+                truncation=True,
+                return_tensors="pt",
+            )
+            .input_ids.type(torch.int32)
+            .to(self.torch_device)
+        )
+        uncond_input_ids_inp = device_view(uncond_input_ids)
+        uncond_embeddings = runEngine(self.engine["clip"], {"input_ids": uncond_input_ids_inp}, self.stream)[
+            "text_embeddings"
+        ]
+
+        # Concatenate the unconditional and text embeddings into a single batch to avoid doing two forward passes for classifier free guidance
+        text_embeddings = torch.cat([uncond_embeddings, text_embeddings]).to(dtype=torch.float16)
+
+        return text_embeddings
+
+    def __denoise_latent(
+        self, latents, text_embeddings, timesteps=None, step_offset=0, mask=None, masked_image_latents=None
+    ):
+        if not isinstance(timesteps, torch.Tensor):
+            timesteps = self.scheduler.timesteps
+        for step_index, timestep in enumerate(timesteps):
+            # Expand the latents if we are doing classifier free guidance
+            latent_model_input = torch.cat([latents] * 2)
+            latent_model_input = self.scheduler.scale_model_input(latent_model_input, timestep)
+            if isinstance(mask, torch.Tensor):
+                latent_model_input = torch.cat([latent_model_input, mask, masked_image_latents], dim=1)
+
+            # Predict the noise residual
+            timestep_float = timestep.float() if timestep.dtype != torch.float32 else timestep
+
+            sample_inp = device_view(latent_model_input)
+            timestep_inp = device_view(timestep_float)
+            embeddings_inp = device_view(text_embeddings)
+            noise_pred = runEngine(
+                self.engine["unet"],
+                {"sample": sample_inp, "timestep": timestep_inp, "encoder_hidden_states": embeddings_inp},
+                self.stream,
+            )["latent"]
+
+            # Perform guidance
+            noise_pred_uncond, noise_pred_text = noise_pred.chunk(2)
+            noise_pred = noise_pred_uncond + self.guidance_scale * (noise_pred_text - noise_pred_uncond)
+
+            latents = self.scheduler.step(noise_pred, timestep, latents).prev_sample
+
+        latents = 1.0 / 0.18215 * latents
+        return latents
+
+    def __decode_latent(self, latents):
+        images = runEngine(self.engine["vae"], {"latent": device_view(latents)}, self.stream)["images"]
+        images = (images / 2 + 0.5).clamp(0, 1)
+        return images.cpu().permute(0, 2, 3, 1).float().numpy()
+
+    def __loadResources(self, image_height, image_width, batch_size):
+        self.stream = cuda.Stream()
+
+        # Allocate buffers for TensorRT engine bindings
+        for model_name, obj in self.models.items():
+            self.engine[model_name].allocate_buffers(
+                shape_dict=obj.get_shape_dict(batch_size, image_height, image_width), device=self.torch_device
+            )
+
+    @torch.no_grad()
+    def __call__(
+        self,
+        prompt: Union[str, List[str]] = None,
+        num_inference_steps: int = 50,
+        guidance_scale: float = 7.5,
+        negative_prompt: Optional[Union[str, List[str]]] = None,
+        generator: Optional[Union[torch.Generator, List[torch.Generator]]] = None,
+    ):
+        r"""
+        Function invoked when calling the pipeline for generation.
+
+        Args:
+            prompt (`str` or `List[str]`, *optional*):
+                The prompt or prompts to guide the image generation. If not defined, one has to pass `prompt_embeds`.
+                instead.
+            num_inference_steps (`int`, *optional*, defaults to 50):
+                The number of denoising steps. More denoising steps usually lead to a higher quality image at the
+                expense of slower inference.
+            guidance_scale (`float`, *optional*, defaults to 7.5):
+                Guidance scale as defined in [Classifier-Free Diffusion Guidance](https://arxiv.org/abs/2207.12598).
+                `guidance_scale` is defined as `w` of equation 2. of [Imagen
+                Paper](https://arxiv.org/pdf/2205.11487.pdf). Guidance scale is enabled by setting `guidance_scale >
+                1`. Higher guidance scale encourages to generate images that are closely linked to the text `prompt`,
+                usually at the expense of lower image quality.
+            negative_prompt (`str` or `List[str]`, *optional*):
+                The prompt or prompts not to guide the image generation. If not defined, one has to pass
+                `negative_prompt_embeds`. instead. If not defined, one has to pass `negative_prompt_embeds`. instead.
+                Ignored when not using guidance (i.e., ignored if `guidance_scale` is less than `1`).
+            generator (`torch.Generator` or `List[torch.Generator]`, *optional*):
+                One or a list of [torch generator(s)](https://pytorch.org/docs/stable/generated/torch.Generator.html)
+                to make generation deterministic.
+
+        """
+        self.generator = generator
+        self.denoising_steps = num_inference_steps
+        self.guidance_scale = guidance_scale
+
+        # Pre-compute latent input scales and linear multistep coefficients
+        self.scheduler.set_timesteps(self.denoising_steps, device=self.torch_device)
+
+        # Define call parameters
+        if prompt is not None and isinstance(prompt, str):
+            batch_size = 1
+            prompt = [prompt]
+        elif prompt is not None and isinstance(prompt, list):
+            batch_size = len(prompt)
+        else:
+            raise ValueError(f"Expected prompt to be of type list or str but got {type(prompt)}")
+
+        if negative_prompt is None:
+            negative_prompt = [""] * batch_size
+
+        if negative_prompt is not None and isinstance(negative_prompt, str):
+            negative_prompt = [negative_prompt]
+
+        assert len(prompt) == len(negative_prompt)
+
+        if batch_size > self.max_batch_size:
+            raise ValueError(
+                f"Batch size {len(prompt)} is larger than allowed {self.max_batch_size}. If dynamic shape is used, then maximum batch size is 4"
+            )
+
+        # load resources
+        self.__loadResources(self.image_height, self.image_width, batch_size)
+
+        with torch.inference_mode(), torch.autocast("cuda"), trt.Runtime(TRT_LOGGER):
+            # CLIP text encoder
+            text_embeddings = self.__encode_prompt(prompt, negative_prompt)
+
+            # Pre-initialize latents
+            num_channels_latents = self.unet.in_channels
+            latents = self.prepare_latents(
+                batch_size,
+                num_channels_latents,
+                self.image_height,
+                self.image_width,
+                torch.float32,
+                self.torch_device,
+                generator,
+            )
+
+            # UNet denoiser
+            latents = self.__denoise_latent(latents, text_embeddings)
+
+            # VAE decode latent
+            images = self.__decode_latent(latents)
+
+        images, has_nsfw_concept = self.run_safety_checker(images, self.torch_device, text_embeddings.dtype)
+        images = self.numpy_to_pil(images)
+        return StableDiffusionPipelineOutput(images=images, nsfw_content_detected=has_nsfw_concept)