一、导出为dynamic shape

1）函数讲解（函数导出、输出检查）

①torch.onnx.export

    torch.onnx.export(
        clip_model,
        (tokens),
        onnx_path,
        verbose=True,
        opset_version=18,
        do_constant_folding=True,
        input_names=input_names,
        output_names=output_names,
        dynamic_axes=dynamic_axes,
    )

(1)export_params:默认为true，表示导出的 ONNX 模型文件会包含模型的所有参数（如权重、偏置等）。而当设置为 False 时，导出的 ONNX 模型文件仅包含模型的计算图结构，不包含模型的参数。这意味着导出的 ONNX 文件会小很多，因为它没有存储大量的参数数据
(2)verbose：为true表示，将会输出大量打印日志信息
(3)do_constant_folding：一般为true，是一个布尔类型的参数，其作用是控制在导出 ONNX 模型时是否进行常量折叠优化从而提高推理性能。为TRUE开启常量折叠优化。在导出 ONNX 模型时，会对图中所有仅包含常量输入的操作进行预先计算，并用计算结果替换这些操作，以此简化计算图，减少模型的计算量和复杂度。
(4)input_names和output_names：输入、输出参数
(5)dynamic_axes：是一个字典，其键为输入或输出张量的名称，值也是一个字典，用于指定该张量中哪些维度是动态的。内层字典的键是维度索引（从 0 开始），值是一个字符串，用于标识这个动态维度，通常在 ONNX 运行时会使用这个标识来指定具体的维度大小
(6)opset_version：指定optset的版本

输入参数举例：
    dynamic_axes = {
   
        "x": {
   0: "batch_size"},
        "hint": {
   0: "batch_size"},
        "timesteps": {
   0: "batch_size"},
        "context": {
   0: "batch_size", 1: "sequence_length"},
        "output": {
   0: "batch_size", 1: "hint_height", 2: "hint_width"}
    }
    
	dynamic_axes = {
   "input_ids": {
   1: "S"}, "last_hidden_state": {
   1: "S"}}
    
        dynamic_axes = {
   
        "x": {
   0: "latent"},
    }

②误差检查

#onnx_path onnx文件目录
#input_dicts  输入参数
#torch_outputs  模型输出结果
def onnxruntime_check(onnx_path, input_dicts, torch_outputs):
    onnx_model = onnx.load(onnx_path)
    # onnx.checker.check_model(onnx_model)
    sess = rt.InferenceSession(onnx_path)
    # outputs = self.get_output_names()
    # latent input
    # data = np.zeros((4, 77), dtype=np.int32)
    result = sess.run(None, input_dicts)
    cnt = 0
    for i in range(0, len(torch_outputs)):
        ret = np.allclose(result[i], torch_outputs[i].detach().numpy(), rtol=1e-03, atol=1e-05, equal_nan=False)
        cnt = cnt +1
        if ret is False:
            #print(f"onnxruntime_check {i} ret:{ret}  result[i]:{result[i]}  torch_outputs[i]:{torch_outputs[i].detach().numpy()} ")
            print("Error onnxruntime_check")
            # import pdb; pdb.set_trace()
        #print("cnt:", cnt)

2）代码展示

• 代码

import numpy as np
from pytorch_fid import fid_score
from pytorch_fid.inception import InceptionV3
import cv2
import datetime
from share import *
import config

import cv2
import einops
import gradio as gr
import numpy as np
import torch
import random
import os

from pytorch_lightning import seed_everything
from annotator.util import resize_image, HWC3
from annotator.canny import CannyDetector
from cldm.model import create_model, load_state_dict
from cldm.ddim_hacked import DDIMSampler
from onnx import shape_inference
import onnx_graphsurgeon as gs
import onnx
import onnxruntime as rt

def optimize(onnx_path, opt_onnx_path):
    from onnxsim import simplify
    model = onnx.load(onnx_path)
    graph = gs.import_onnx(model)
    print(f"{
     onnx_path} simplify start !")
    # self.info("init", graph)
    model_simp, check = simplify(model)
    # self.info("opt", gs.import_onnx(model_simp))
    onnx.save(model_simp, opt_onnx_path, save_as_external_data=True)
    assert check, "Simplified ONNX model could not be validated"
    print(f"{
     onnx_path} simplify done !")

def onnxruntime_check(onnx_path, input_dicts, torch_outputs):
    onnx_model = onnx.load(onnx_path)
    # onnx.checker.check_model(onnx_model)
    sess = rt.InferenceSession(onnx_path)
    # outputs = self.get_output_names()
    # latent input
    # data = np.zeros((4, 77), dtype=np.int32)
    result = sess.run(None, input_dicts)
    cnt = 0
    for i in range(0, len(torch_outputs)):
        ret = np.allclose(result[i], torch_outputs[i].detach().numpy(), rtol=1e-03, atol=1e-05, equal_nan=False)
        cnt = cnt +1
        if ret is False:
            #print(f"onnxruntime_check {i} ret:{ret}  result[i]:{result[i]}  torch_outputs[i]:{torch_outputs[i].detach().numpy()} ")
            print("Error onnxruntime_check")
            # import pdb; pdb.set_trace()
        #print("cnt:", cnt)
    


class hackathon():
    def initialize(self):
        self.apply_canny = CannyDetector()
        self.model = create_model('./models/cldm_v15.yaml').cpu()
        self.model.load_state_dict(load_state_dict('./models/control_sd15_canny.pth', location='cpu'))
        # self.model.load_state_dict(load_state_dict('/home/player/ControlNet/models/control_sd15_canny.pth', location='cuda'))
        self.model = self.model.cpu()
        self.model.eval()
        self.ddim_sampler = DDIMSampler(self.model)

hk = hackathon()
hk.initialize()

def export_clip_model():
    clip_model = hk.model.cond_stage_model

    import types

    def forward(self, tokens):
        outputs = self.transformer(
            input_ids=tokens, output_hidden_states=self.layer == "hidden"
        )
        if self.layer == "last":
            z = outputs.last_hidden_state
        elif self.layer == "pooled":
            z = outputs.pooler_output[:, None, :]
        else:
            z = outputs.hidden_states[self.layer_idx]
        return z

    clip_model.forward = types.MethodType(forward, clip_model)

    onnx_path = "./onnx/CLIP.onnx"

    tokens = torch.zeros(1, 77, dtype=torch.int32)
    input_names = ["input_ids"]
    output_names = ["last_hidden_state"]
    dynamic_axes = {
   "input_ids": {
   1: "S"}, "last_hidden_state": {
   1: "S"}}

    torch.onnx.export(
        clip_model,
        (tokens),
        onnx_path,
        verbose=True,
        opset_version=18,
        do_constant_folding=True,
        input_names=input_names,
        output_names=output_names,
        dynamic_axes=dynamic_axes,
    )
    print("======================= CLIP model export onnx done!")

    # verify onnx model
    output = clip_model(tokens)
    input_dicts = {
   "input_ids": tokens.numpy()}
    onnxruntime_check(onnx_path, input_dicts, [output])
    print("======================= CLIP onnx model verify done!")

    # opt_onnx_path = "./onnx/CLIP.opt.onnx"
    # optimize(onnx_path, opt_onnx_path)

def export_control_net_model():
    control_net_model = hk.model.control_model
    onnx_path = "./onnx/control_net_model.onnx"

    def get_shape(B=1,S=64):
        return [(B, 4, 32, 48),(B, 3, 256, 384),tuple([B])