Stable-Diffusion-webUI 代码阅读01 —— 从启动开始

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Stable-Diffusion-webUI 代码阅读01 —— 从启动开始

由于实习工作需要，决定用几天时间阅读一遍stable-diffusion-webui的代码。

本文参考知乎专栏，并且做出了一定程度上的改进，感谢大佬！知乎专栏：自动做游戏：AI技术落地于游戏开发 - 知乎 (zhihu.com)

最近工作主要侧重于OneFlow框架应用于SD的加速和不同Sampler的支持适配的工作，所以阅读代码也将其作为切入点。

由于本人刚刚入门，故许多内容比较粗糙，有问题希望多多批评指正！

webui本身更新较快，本文所阅读的内容为 AUTOMATIC1111大佬的1.4.1，这里是项目地址

webui，启动！—— webui.sh

stable-diffusion的启动：

bash webui.sh -f

这里添加的-f是因为，SD不允许root用户进行启动，~~可是公司租用的服务器的配置的却是root的权限~~,故加入-f，轻松解决，作为一个实习生，也不乱干扰服务器的配置。

检测系统与环境

# If run from macOS, load defaults from webui-macos-env.sh
if [[ "$OSTYPE" == "darwin"* ]]; then
    if [[ -f webui-macos-env.sh ]]
        then
        source ./webui-macos-env.sh
    fi
fi

检测当前系统是否为macOS，如果是，则检测并加载webui-macos-env.sh

如果环境不是macOS，那么

if [[ -f webui-user.sh ]]
then
    source ./webui-user.sh
fi

检测并加载webui-user.sh

webui-macos-env.sh

#!/bin/bash
####################################################################
#                          macOS defaults                          #
# Please modify webui-user.sh to change these instead of this file #
####################################################################

if [[ -x "$(command -v python3.10)" ]]
then
    python_cmd="python3.10"
fi

export install_dir="$HOME"
export COMMANDLINE_ARGS="--skip-torch-cuda-test --upcast-sampling --no-half-vae --use-cpu interrogate"
export TORCH_COMMAND="pip install torch==2.0.1 torchvision==0.15.2"
export K_DIFFUSION_REPO="https://github.com/brkirch/k-diffusion.git"
export K_DIFFUSION_COMMIT_HASH="51c9778f269cedb55a4d88c79c0246d35bdadb71"
export PYTORCH_ENABLE_MPS_FALLBACK=1

####################################################################

可以看到，要求修改webui.sh

默认的一些变量配置包括：

python环境
install_dir的默认路径
COMMANDLINE_ARGS 额外的命令行参数
- --skip-torch-cuda-test 如果是nvidia显卡，不需要加这个参数
- --upcast-sampling 向上采样。通常产生与--no-half（不将模型切换为16位浮点数）相同的效果，在较少的内存下效果更好
- --no-half-vae 不将VAE模型切换为16位浮点数
- --use-cpu interrogate 使用CPU
TORCH环境
K_Diffusion
- 仓库地址
- 具体的某次commit的哈希值
启用pytorch的MPS回退功能，MPS是CUDA提供的多进程服务，启用该功能可以提高GPU的利用率和计算性能

webui-user.sh

#!/bin/bash
#########################################################
# Uncomment and change the variables below to your need:#
#########################################################

# Install directory without trailing slash
#install_dir="/home/$(whoami)"

# Name of the subdirectory
#clone_dir="stable-diffusion-webui"

# Commandline arguments for webui.py, for example: export COMMANDLINE_ARGS="--medvram --opt-split-attention"
#export COMMANDLINE_ARGS=""

# python3 executable
#python_cmd="python3"

# git executable
#export GIT="git"

# python3 venv without trailing slash (defaults to ${install_dir}/${clone_dir}/venv)
#venv_dir="venv"

# script to launch to start the app
#export LAUNCH_SCRIPT="launch.py"

# install command for torch
#export TORCH_COMMAND="pip install torch==1.12.1+cu113 --extra-index-url https://download.pytorch.org/whl/cu113"

# Requirements file to use for stable-diffusion-webui
#export REQS_FILE="requirements_versions.txt"

# Fixed git repos
#export K_DIFFUSION_PACKAGE=""
#export GFPGAN_PACKAGE=""

# Fixed git commits
#export STABLE_DIFFUSION_COMMIT_HASH=""
#export CODEFORMER_COMMIT_HASH=""
#export BLIP_COMMIT_HASH=""

# Uncomment to enable accelerated launch
#export ACCELERATE="True"

# Uncomment to disable TCMalloc
#export NO_TCMALLOC="True"

###########################################

可以看到这里全是注释掉的，用户设置一些参数，可以设置的比如python指令，git指令，虚拟环境地址等等。

变量默认值

# Set defaults
# Install directory without trailing slash
if [[ -z "${install_dir}" ]]
then
    install_dir="$(pwd)"
fi

# Name of the subdirectory (defaults to stable-diffusion-webui)
if [[ -z "${clone_dir}" ]]
then
    clone_dir="stable-diffusion-webui"
fi

# python3 executable
if [[ -z "${python_cmd}" ]]
then
    python_cmd="python3"
fi

# git executable
if [[ -z "${GIT}" ]]
then
    export GIT="git"
fi

# python3 venv without trailing slash (defaults to ${install_dir}/${clone_dir}/venv)
if [[ -z "${venv_dir}" ]]
then
    venv_dir="venv"
fi

if [[ -z "${LAUNCH_SCRIPT}" ]]
then
    LAUNCH_SCRIPT="launch.py"
fi

这里可以看到是一些关于安装目录，子文件夹名字，python指令，git指令，虚拟环境地址等。

整体内容大概相同，至于各个参数的详解，可以看b站大佬的这篇文章：最详细的WEBUI启动参数 - 哔哩哔哩 (bilibili.com)

root权限判断

# this script cannot be run as root by default
can_run_as_root=0

# read any command line flags to the webui.sh script
while getopts "f" flag > /dev/null 2>&1
do
    case ${flag} in
        f) can_run_as_root=1;;
        *) break;;
    esac
done

# Disable sentry logging
export ERROR_REPORTING=FALSE

# Do not reinstall existing pip packages on Debian/Ubuntu
export PIP_IGNORE_INSTALLED=0

# Pretty print
delimiter="################################################################"

printf "\n%s\n" "${delimiter}"
printf "\e[1m\e[32mInstall script for stable-diffusion + Web UI\n"
printf "\e[1m\e[34mTested on Debian 11 (Bullseye)\e[0m"
printf "\n%s\n" "${delimiter}"

# Do not run as root
if [[ $(id -u) -eq 0 && can_run_as_root -eq 0 ]]
then
    printf "\n%s\n" "${delimiter}"
    printf "\e[1m\e[31mERROR: This script must not be launched as root, aborting...\e[0m"
    printf "\n%s\n" "${delimiter}"
    exit 1
else
    printf "\n%s\n" "${delimiter}"
    printf "Running on \e[1m\e[32m%s\e[0m user" "$(whoami)"
    printf "\n%s\n" "${delimiter}"
fi

if [[ $(getconf LONG_BIT) = 32 ]]
then
    printf "\n%s\n" "${delimiter}"
    printf "\e[1m\e[31mERROR: Unsupported Running on a 32bit OS\e[0m"
    printf "\n%s\n" "${delimiter}"
    exit 1
fi

if [[ -d .git ]]
then
    printf "\n%s\n" "${delimiter}"
    printf "Repo already cloned, using it as install directory"
    printf "\n%s\n" "${delimiter}"
    install_dir="${PWD}/../"
    clone_dir="${PWD##*/}"
fi

其实加入-f就可以了，获得id来判断是否为root用户，并且一次来判断是否能够继续运行程序

除了root用户以外，还对32位系统进行了限制。

获取gpu信息，获取git和python信息

# Check prerequisites
gpu_info=$(lspci 2>/dev/null | grep -E "VGA|Display")
case "$gpu_info" in
    *"Navi 1"*)
        export HSA_OVERRIDE_GFX_VERSION=10.3.0
        if [[ -z "${TORCH_COMMAND}" ]]
        then
            pyv="$(${python_cmd} -c 'import sys; print(".".join(map(str, sys.version_info[0:2])))')"
            if [[ $(bc <<< "$pyv <= 3.10") -eq 1 ]] 
            then
                # Navi users will still use torch 1.13 because 2.0 does not seem to work.
                export TORCH_COMMAND="pip install torch==1.13.1+rocm5.2 torchvision==0.14.1+rocm5.2 --index-url https://download.pytorch.org/whl/rocm5.2"
            else
                printf "\e[1m\e[31mERROR: RX 5000 series GPUs must be using at max python 3.10, aborting...\e[0m"
                exit 1
            fi
        fi
    ;;
    *"Navi 2"*) export HSA_OVERRIDE_GFX_VERSION=10.3.0
    ;;
    *"Renoir"*) export HSA_OVERRIDE_GFX_VERSION=9.0.0
        printf "\n%s\n" "${delimiter}"
        printf "Experimental support for Renoir: make sure to have at least 4GB of VRAM and 10GB of RAM or enable cpu mode: --use-cpu all --no-half"
        printf "\n%s\n" "${delimiter}"
    ;;
    *)
    ;;
esac
if ! echo "$gpu_info" | grep -q "NVIDIA";
then
    if echo "$gpu_info" | grep -q "AMD" && [[ -z "${TORCH_COMMAND}" ]]
    then
        export TORCH_COMMAND="pip install torch==2.0.1+rocm5.4.2 torchvision==0.15.2+rocm5.4.2 --index-url https://download.pytorch.org/whl/rocm5.4.2"
    fi
fi

for preq in "${GIT}" "${python_cmd}"
do
    if ! hash "${preq}" &>/dev/null
    then
        printf "\n%s\n" "${delimiter}"
        printf "\e[1m\e[31mERROR: %s is not installed, aborting...\e[0m" "${preq}"
        printf "\n%s\n" "${delimiter}"
        exit 1
    fi
done

这部分没什么可说的，都是一些环境设置的架构级别的逻辑。暂时掠过

创建或激活python虚拟环境

if ! "${python_cmd}" -c "import venv" &>/dev/null
then
    printf "\n%s\n" "${delimiter}"
    printf "\e[1m\e[31mERROR: python3-venv is not installed, aborting...\e[0m"
    printf "\n%s\n" "${delimiter}"
    exit 1
fi

cd "${install_dir}"/ || { printf "\e[1m\e[31mERROR: Can't cd to %s/, aborting...\e[0m" "${install_dir}"; exit 1; }
if [[ -d "${clone_dir}" ]]
then
    cd "${clone_dir}"/ || { printf "\e[1m\e[31mERROR: Can't cd to %s/%s/, aborting...\e[0m" "${install_dir}" "${clone_dir}"; exit 1; }
else
    printf "\n%s\n" "${delimiter}"
    printf "Clone stable-diffusion-webui"
    printf "\n%s\n" "${delimiter}"
    "${GIT}" clone https://github.com/AUTOMATIC1111/stable-diffusion-webui.git "${clone_dir}"
    cd "${clone_dir}"/ || { printf "\e[1m\e[31mERROR: Can't cd to %s/%s/, aborting...\e[0m" "${install_dir}" "${clone_dir}"; exit 1; }
fi

if [[ -z "${VIRTUAL_ENV}" ]];
then
    printf "\n%s\n" "${delimiter}"
    printf "Create and activate python venv"
    printf "\n%s\n" "${delimiter}"
    cd "${install_dir}"/"${clone_dir}"/ || { printf "\e[1m\e[31mERROR: Can't cd to %s/%s/, aborting...\e[0m" "${install_dir}" "${clone_dir}"; exit 1; }
    if [[ ! -d "${venv_dir}" ]]
    then
        "${python_cmd}" -m venv "${venv_dir}"
        first_launch=1
    fi
    # shellcheck source=/dev/null
    if [[ -f "${venv_dir}"/bin/activate ]]
    then
        source "${venv_dir}"/bin/activate
    else
        printf "\n%s\n" "${delimiter}"
        printf "\e[1m\e[31mERROR: Cannot activate python venv, aborting...\e[0m"
        printf "\n%s\n" "${delimiter}"
        exit 1
    fi
else
    printf "\n%s\n" "${delimiter}"
    printf "python venv already activate: ${VIRTUAL_ENV}"
    printf "\n%s\n" "${delimiter}"
fi

这里主要是检测是否有python虚拟环境，如果没有，那么就创建一个，可以看到包默认存储在./venv的位置

Linux下的配置TCMALLOC

# Try using TCMalloc on Linux
prepare_tcmalloc() {
    if [[ "${OSTYPE}" == "linux"* ]] && [[ -z "${NO_TCMALLOC}" ]] && [[ -z "${LD_PRELOAD}" ]]; then
        TCMALLOC="$(PATH=/usr/sbin:$PATH ldconfig -p | grep -Po "libtcmalloc(_minimal|)\.so\.\d" | head -n 1)"
        if [[ ! -z "${TCMALLOC}" ]]; then
            echo "Using TCMalloc: ${TCMALLOC}"
            export LD_PRELOAD="${TCMALLOC}"
        else
            printf "\e[1m\e[31mCannot locate TCMalloc (improves CPU memory usage)\e[0m\n"
        fi
    fi
}

如果在Linux下设置了NO_TCMALLOC和LD_PERLOAD的环境变量，那么就会在/user/bin目录下搜索libtcmalloc相关的动态库，并且将名称赋值给LD_PRELOAD，以便在后续过程中进行预加载动态库。

TCMalloc是一个在Linux系统中用来优化CPU内存使用的工具。

判断accelerate

KEEP_GOING=1
export SD_WEBUI_RESTART=tmp/restart
while [[ "$KEEP_GOING" -eq "1" ]]; do
    if [[ ! -z "${ACCELERATE}" ]] && [ ${ACCELERATE}="True" ] && [ -x "$(command -v accelerate)" ]; then
        printf "\n%s\n" "${delimiter}"
        printf "Accelerating launch.py..."
        printf "\n%s\n" "${delimiter}"
        prepare_tcmalloc
        accelerate launch --num_cpu_threads_per_process=6 "${LAUNCH_SCRIPT}" "$@"
    else
        printf "\n%s\n" "${delimiter}"
        printf "Launching launch.py..."
        printf "\n%s\n" "${delimiter}"
        prepare_tcmalloc
        "${python_cmd}" "${LAUNCH_SCRIPT}" "$@"
    fi

    if [[ ! -f tmp/restart ]]; then
        KEEP_GOING=0
    fi
done

accelerate是Hugging Face发布的一个库，可以进行分布式运行，用来加速pytorch。

launch.py

# launch.py
from modules import launch_utils


args = launch_utils.args
python = launch_utils.python
git = launch_utils.git
index_url = launch_utils.index_url
dir_repos = launch_utils.dir_repos

commit_hash = launch_utils.commit_hash
git_tag = launch_utils.git_tag

run = launch_utils.run
is_installed = launch_utils.is_installed
repo_dir = launch_utils.repo_dir

run_pip = launch_utils.run_pip
check_run_python = launch_utils.check_run_python
git_clone = launch_utils.git_clone
git_pull_recursive = launch_utils.git_pull_recursive
run_extension_installer = launch_utils.run_extension_installer
prepare_environment = launch_utils.prepare_environment
configure_for_tests = launch_utils.configure_for_tests
start = launch_utils.start


def main():
    if not args.skip_prepare_environment:
        prepare_environment()

    if args.test_server:
        configure_for_tests()

    start()


if __name__ == "__main__":
    main()

终于到了比较熟悉的python了，前文中所指的LAUNCH_SCRIPT默认指的就是这个文件，此代码main函数内主要完成三件事

环境准备
测试configure配置
启动

对于环境准备和configure配置的，可以重点去关注launch_utils.py，由于技术路线更关注模型推理部分，故跳过

start

# modules/launch_utils.py
def start():
    print(f"Launching {'API server' if '--nowebui' in sys.argv else 'Web UI'} with arguments: {' '.join(sys.argv[1:])}")
    import webui
    if '--nowebui' in sys.argv:
        webui.api_only()
    else:
        webui.webui()

这里是launch_utils.py，也就是刚刚在launch.py里调用的start()的部分，可以看到，这里分为两种启动方式

API启动
webUI启动

API启动

# webui.py
def api_only():
    initialize()

    app = FastAPI()
    setup_middleware(app)
    api = create_api(app)

    modules.script_callbacks.app_started_callback(None, app)

    print(f"Startup time: {startup_timer.summary()}.")
    api.launch(server_name="0.0.0.0" if cmd_opts.listen else "127.0.0.1", port=cmd_opts.port if cmd_opts.port else 7861)

其中，在initialize中，对于模型等一些基本参数和策略进行了初始化，先不一一分析，后面申请的API，之后启动api等，逻辑较为简单，也不过分深入。

WebUI启动

Gradio

SD基于开源项目Gradio搭建，这里有快速搭建的教程: Gradio：轻松实现AI算法可视化部署 - 知乎 (zhihu.com)

这里需要注意gradio默认的端口号为7860

webui窗口的构建

def webui():
    launch_api = cmd_opts.api
    initialize()

    while 1:
        if shared.opts.clean_temp_dir_at_start:
            ui_tempdir.cleanup_tmpdr()
            startup_timer.record("cleanup temp dir")

        modules.script_callbacks.before_ui_callback()
        startup_timer.record("scripts before_ui_callback")

        shared.demo = modules.ui.create_ui()
        startup_timer.record("create ui")

        if not cmd_opts.no_gradio_queue:
            shared.demo.queue(64)

        gradio_auth_creds = list(get_gradio_auth_creds()) or None

        app, local_url, share_url = shared.demo.launch(
            share=cmd_opts.share,
            server_name=server_name,
            server_port=cmd_opts.port,
            ssl_keyfile=cmd_opts.tls_keyfile,
            ssl_certfile=cmd_opts.tls_certfile,
            ssl_verify=cmd_opts.disable_tls_verify,
            debug=cmd_opts.gradio_debug,
            auth=gradio_auth_creds,
            inbrowser=cmd_opts.autolaunch and os.getenv('SD_WEBUI_RESTARTING ') != '1',
            prevent_thread_lock=True,
            allowed_paths=cmd_opts.gradio_allowed_path,
            app_kwargs={
                "docs_url": "/docs",
                "redoc_url": "/redoc",
            },
        )
        if cmd_opts.add_stop_route:
            app.add_route("/_stop", stop_route, methods=["POST"])

        # after initial launch, disable --autolaunch for subsequent restarts
        cmd_opts.autolaunch = False

        startup_timer.record("gradio launch")

        # gradio uses a very open CORS policy via app.user_middleware, which makes it possible for
        # an attacker to trick the user into opening a malicious HTML page, which makes a request to the
        # running web ui and do whatever the attacker wants, including installing an extension and
        # running its code. We disable this here. Suggested by RyotaK.
        app.user_middleware = [x for x in app.user_middleware if x.cls.__name__ != 'CORSMiddleware']

        setup_middleware(app)

        modules.progress.setup_progress_api(app)
        modules.ui.setup_ui_api(app)

        if launch_api:
            create_api(app)

        ui_extra_networks.add_pages_to_demo(app)

        startup_timer.record("add APIs")

        with startup_timer.subcategory("app_started_callback"):
            modules.script_callbacks.app_started_callback(shared.demo, app)

        timer.startup_record = startup_timer.dump()
        print(f"Startup time: {startup_timer.summary()}.")

        if cmd_opts.subpath:
            redirector = FastAPI()
            redirector.get("/")
            gradio.mount_gradio_app(redirector, shared.demo, path=f"/{cmd_opts.subpath}")

        try:
            while True:
                server_command = shared.state.wait_for_server_command(timeout=5)
                if server_command:
                    if server_command in ("stop", "restart"):
                        break
                    else:
                        print(f"Unknown server command: {server_command}")
        except KeyboardInterrupt:
            print('Caught KeyboardInterrupt, stopping...')
            server_command = "stop"

        if server_command == "stop":
            print("Stopping server...")
            # If we catch a keyboard interrupt, we want to stop the server and exit.
            shared.demo.close()
            break

        print('Restarting UI...')
        shared.demo.close()
        time.sleep(0.5)
        startup_timer.reset()
        modules.script_callbacks.app_reload_callback()
        startup_timer.record("app reload callback")
        modules.script_callbacks.script_unloaded_callback()
        startup_timer.record("scripts unloaded callback")
        initialize_rest(reload_script_modules=True)

这里的create_ui方法以及launch方法，就是构建了UI界面的方法，这里稍微简单看一下UI界面对应的内容：

图中的with gr.Blocks所对应的就是WebUI内的各个TabBar，比如txt2img,img2img等

在这里随便打开一个代码块，比如这里来看txt2img

    with gr.Blocks(analytics_enabled=False) as txt2img_interface:
        txt2img_prompt, txt2img_prompt_styles, txt2img_negative_prompt, submit, _, _, txt2img_prompt_style_apply, txt2img_save_style, txt2img_paste, extra_networks_button, token_counter, token_button, negative_token_counter, negative_token_button, restore_progress_button = create_toprow(is_img2img=False)

        dummy_component = gr.Label(visible=False)
        txt_prompt_img = gr.File(label="", elem_id="txt2img_prompt_image", file_count="single", type="binary", visible=False)

        with FormRow(variant='compact', elem_id="txt2img_extra_networks", visible=False) as extra_networks:
            from modules import ui_extra_networks
            extra_networks_ui = ui_extra_networks.create_ui(extra_networks, extra_networks_button, 'txt2img')

        with gr.Row().style(equal_height=False):
            with gr.Column(variant='compact', elem_id="txt2img_settings"):
                modules.scripts.scripts_txt2img.prepare_ui()

                for category in ordered_ui_categories():
                    if category == "sampler":
                        steps, sampler_index = create_sampler_and_steps_selection(samplers, "txt2img")

                    elif category == "dimensions":
                        with FormRow():
                            with gr.Column(elem_id="txt2img_column_size", scale=4):
                                width = gr.Slider(minimum=64, maximum=2048, step=8, label="Width", value=512, elem_id="txt2img_width")
                                height = gr.Slider(minimum=64, maximum=2048, step=8, label="Height", value=512, elem_id="txt2img_height")

                            with gr.Column(elem_id="txt2img_dimensions_row", scale=1, elem_classes="dimensions-tools"):
                                res_switch_btn = ToolButton(value=switch_values_symbol, elem_id="txt2img_res_switch_btn", label="Switch dims")

                            if opts.dimensions_and_batch_together:
                                with gr.Column(elem_id="txt2img_column_batch"):
                                    batch_count = gr.Slider(minimum=1, step=1, label='Batch count', value=1, elem_id="txt2img_batch_count")
                                    batch_size = gr.Slider(minimum=1, maximum=8, step=1, label='Batch size', value=1, elem_id="txt2img_batch_size")

                    elif category == "cfg":
                        cfg_scale = gr.Slider(minimum=1.0, maximum=30.0, step=0.5, label='CFG Scale', value=7.0, elem_id="txt2img_cfg_scale")

                    elif category == "seed":
                        seed, reuse_seed, subseed, reuse_subseed, subseed_strength, seed_resize_from_h, seed_resize_from_w, seed_checkbox = create_seed_inputs('txt2img')

                    elif category == "checkboxes":
                        with FormRow(elem_classes="checkboxes-row", variant="compact"):
                            restore_faces = gr.Checkbox(label='Restore faces', value=False, visible=len(shared.face_restorers) > 1, elem_id="txt2img_restore_faces")
                            tiling = gr.Checkbox(label='Tiling', value=False, elem_id="txt2img_tiling")
                            enable_hr = gr.Checkbox(label='Hires. fix', value=False, elem_id="txt2img_enable_hr")
                            hr_final_resolution = FormHTML(value="", elem_id="txtimg_hr_finalres", label="Upscaled resolution", interactive=False)

                    elif category == "hires_fix":
                        with FormGroup(visible=False, elem_id="txt2img_hires_fix") as hr_options:
                            with FormRow(elem_id="txt2img_hires_fix_row1", variant="compact"):
                                hr_upscaler = gr.Dropdown(label="Upscaler", elem_id="txt2img_hr_upscaler", choices=[*shared.latent_upscale_modes, *[x.name for x in shared.sd_upscalers]], value=shared.latent_upscale_default_mode)
                                hr_second_pass_steps = gr.Slider(minimum=0, maximum=150, step=1, label='Hires steps', value=0, elem_id="txt2img_hires_steps")
                                denoising_strength = gr.Slider(minimum=0.0, maximum=1.0, step=0.01, label='Denoising strength', value=0.7, elem_id="txt2img_denoising_strength")

                            with FormRow(elem_id="txt2img_hires_fix_row2", variant="compact"):
                                hr_scale = gr.Slider(minimum=1.0, maximum=4.0, step=0.05, label="Upscale by", value=2.0, elem_id="txt2img_hr_scale")
                                hr_resize_x = gr.Slider(minimum=0, maximum=2048, step=8, label="Resize width to", value=0, elem_id="txt2img_hr_resize_x")
                                hr_resize_y = gr.Slider(minimum=0, maximum=2048, step=8, label="Resize height to", value=0, elem_id="txt2img_hr_resize_y")

                            with FormRow(elem_id="txt2img_hires_fix_row3", variant="compact", visible=opts.hires_fix_show_sampler) as hr_sampler_container:
                                hr_sampler_index = gr.Dropdown(label='Hires sampling method', elem_id="hr_sampler", choices=["Use same sampler"] + [x.name for x in samplers_for_img2img], value="Use same sampler", type="index")

                            with FormRow(elem_id="txt2img_hires_fix_row4", variant="compact", visible=opts.hires_fix_show_prompts) as hr_prompts_container:
                                with gr.Column(scale=80):
                                    with gr.Row():
                                        hr_prompt = gr.Textbox(label="Hires prompt", elem_id="hires_prompt", show_label=False, lines=3, placeholder="Prompt for hires fix pass.\nLeave empty to use the same prompt as in first pass.", elem_classes=["prompt"])
                                with gr.Column(scale=80):
                                    with gr.Row():
                                        hr_negative_prompt = gr.Textbox(label="Hires negative prompt", elem_id="hires_neg_prompt", show_label=False, lines=3, placeholder="Negative prompt for hires fix pass.\nLeave empty to use the same negative prompt as in first pass.", elem_classes=["prompt"])

                    elif category == "batch":
                        if not opts.dimensions_and_batch_together:
                            with FormRow(elem_id="txt2img_column_batch"):
                                batch_count = gr.Slider(minimum=1, step=1, label='Batch count', value=1, elem_id="txt2img_batch_count")
                                batch_size = gr.Slider(minimum=1, maximum=8, step=1, label='Batch size', value=1, elem_id="txt2img_batch_size")

                    elif category == "override_settings":
                        with FormRow(elem_id="txt2img_override_settings_row") as row:
                            override_settings = create_override_settings_dropdown('txt2img', row)

                    elif category == "scripts":
                        with FormGroup(elem_id="txt2img_script_container"):
                            custom_inputs = modules.scripts.scripts_txt2img.setup_ui()

                    else:
                        modules.scripts.scripts_txt2img.setup_ui_for_section(category)

            hr_resolution_preview_inputs = [enable_hr, width, height, hr_scale, hr_resize_x, hr_resize_y]

            for component in hr_resolution_preview_inputs:
                event = component.release if isinstance(component, gr.Slider) else component.change

                event(
                    fn=calc_resolution_hires,
                    inputs=hr_resolution_preview_inputs,
                    outputs=[hr_final_resolution],
                    show_progress=False,
                )
                event(
                    None,
                    _js="onCalcResolutionHires",
                    inputs=hr_resolution_preview_inputs,
                    outputs=[],
                    show_progress=False,
                )

            txt2img_gallery, generation_info, html_info, html_log = create_output_panel("txt2img", opts.outdir_txt2img_samples)

            connect_reuse_seed(seed, reuse_seed, generation_info, dummy_component, is_subseed=False)
            connect_reuse_seed(subseed, reuse_subseed, generation_info, dummy_component, is_subseed=True)

            txt2img_args = dict(
                fn=wrap_gradio_gpu_call(modules.txt2img.txt2img, extra_outputs=[None, '', '']),
                _js="submit",
                inputs=[
                    dummy_component,
                    txt2img_prompt,
                    txt2img_negative_prompt,
                    txt2img_prompt_styles,
                    steps,
                    sampler_index,
                    restore_faces,
                    tiling,
                    batch_count,
                    batch_size,
                    cfg_scale,
                    seed,
                    subseed, subseed_strength, seed_resize_from_h, seed_resize_from_w, seed_checkbox,
                    height,
                    width,
                    enable_hr,
                    denoising_strength,
                    hr_scale,
                    hr_upscaler,
                    hr_second_pass_steps,
                    hr_resize_x,
                    hr_resize_y,
                    hr_sampler_index,
                    hr_prompt,
                    hr_negative_prompt,
                    override_settings,

                ] + custom_inputs,

                outputs=[
                    txt2img_gallery,
                    generation_info,
                    html_info,
                    html_log,
                ],
                show_progress=False,
            )

            txt2img_prompt.submit(**txt2img_args)
            submit.click(**txt2img_args)

            res_switch_btn.click(fn=None, _js="function(){switchWidthHeight('txt2img')}", inputs=None, outputs=None, show_progress=False)

            restore_progress_button.click(
                fn=progress.restore_progress,
                _js="restoreProgressTxt2img",
                inputs=[dummy_component],
                outputs=[
                    txt2img_gallery,
                    generation_info,
                    html_info,
                    html_log,
                ],
                show_progress=False,
            )

            txt_prompt_img.change(
                fn=modules.images.image_data,
                inputs=[
                    txt_prompt_img
                ],
                outputs=[
                    txt2img_prompt,
                    txt_prompt_img
                ],
                show_progress=False,
            )

            enable_hr.change(
                fn=lambda x: gr_show(x),
                inputs=[enable_hr],
                outputs=[hr_options],
                show_progress = False,
            )

            txt2img_paste_fields = [
                (txt2img_prompt, "Prompt"),
                (txt2img_negative_prompt, "Negative prompt"),
                (steps, "Steps"),
                (sampler_index, "Sampler"),
                (restore_faces, "Face restoration"),
                (cfg_scale, "CFG scale"),
                (seed, "Seed"),
                (width, "Size-1"),
                (height, "Size-2"),
                (batch_size, "Batch size"),
                (subseed, "Variation seed"),
                (subseed_strength, "Variation seed strength"),
                (seed_resize_from_w, "Seed resize from-1"),
                (seed_resize_from_h, "Seed resize from-2"),
                (txt2img_prompt_styles, lambda d: d["Styles array"] if isinstance(d.get("Styles array"), list) else gr.update()),
                (denoising_strength, "Denoising strength"),
                (enable_hr, lambda d: "Denoising strength" in d),
                (hr_options, lambda d: gr.Row.update(visible="Denoising strength" in d)),
                (hr_scale, "Hires upscale"),
                (hr_upscaler, "Hires upscaler"),
                (hr_second_pass_steps, "Hires steps"),
                (hr_resize_x, "Hires resize-1"),
                (hr_resize_y, "Hires resize-2"),
                (hr_sampler_index, "Hires sampler"),
                (hr_sampler_container, lambda d: gr.update(visible=True) if d.get("Hires sampler", "Use same sampler") != "Use same sampler" else gr.update()),
                (hr_prompt, "Hires prompt"),
                (hr_negative_prompt, "Hires negative prompt"),
                (hr_prompts_container, lambda d: gr.update(visible=True) if d.get("Hires prompt", "") != "" or d.get("Hires negative prompt", "") != "" else gr.update()),
                *modules.scripts.scripts_txt2img.infotext_fields
            ]
            parameters_copypaste.add_paste_fields("txt2img", None, txt2img_paste_fields, override_settings)
            parameters_copypaste.register_paste_params_button(parameters_copypaste.ParamBinding(
                paste_button=txt2img_paste, tabname="txt2img", source_text_component=txt2img_prompt, source_image_component=None,
            ))

            txt2img_preview_params = [
                txt2img_prompt,
                txt2img_negative_prompt,
                steps,
                sampler_index,
                cfg_scale,
                seed,
                width,
                height,
            ]

            token_button.click(fn=wrap_queued_call(update_token_counter), inputs=[txt2img_prompt, steps], outputs=[token_counter])
            negative_token_button.click(fn=wrap_queued_call(update_token_counter), inputs=[txt2img_negative_prompt, steps], outputs=[negative_token_counter])

            ui_extra_networks.setup_ui(extra_networks_ui, txt2img_gallery)

可以看到，这里的嵌套是比较乱的，但是好在，每个组件的部分名字都和webui的按钮相对应，所以这里可以通过关键词或者js等方式进行检索。

标签：Diffusion,01,prompt,gr,txt2img,hr,webUI,printf,dir
From： https://www.cnblogs.com/ZzTzZ/p/17560934.html

Stable-Diffusion-webUI 代码阅读01 —— 从启动开始