查找 Windows 下载文件夹中的 .webm 文件，选择后转换为 mp4

webm_to_mp4.bat

@echo off
chcp 65001 >nul
setlocal enabledelayedexpansion

:: 防止窗口意外关闭
title WebM to MP4 Converter
echo Starting WebM to MP4 Converter...
echo.

:: 设置搜索目录
set "WATCH_DIR=C:\Users\greatghoul\Downloads"

:: 检查目录是否存在
if not exist "%WATCH_DIR%" (
    echo.
    echo ======================================
    echo ERROR: Directory does not exist
    echo ======================================
    echo Directory: %WATCH_DIR%
    echo.
    echo Press any key to exit...
    pause >nul
    exit /b 1
)

:: 查找所有 .webm 文件（按创建时间倒序）
echo Searching for .webm files in: %WATCH_DIR%
set "FILE_COUNT=0"

:: 使用更简单的方法：直接使用 dir 命令按创建时间倒序
for /f "delims=" %%f in ('dir /b /tc /o-d "%WATCH_DIR%\*.webm" 2^>nul') do (
    set /a FILE_COUNT+=1
    set "FILE_!FILE_COUNT!=%WATCH_DIR%\%%f"
    set "FILENAME_!FILE_COUNT!=%%f"
)

:: 检查是否找到文件
if %FILE_COUNT%==0 (
    echo.
    echo ======================================
    echo No .webm files found
    echo ======================================
    echo Directory: %WATCH_DIR%
    echo.
    echo Press any key to exit...
    pause >nul
    exit /b 1
)

:: 显示文件列表
echo.
echo Found %FILE_COUNT% .webm file(s):
echo.
for /l %%i in (1,1,%FILE_COUNT%) do (
    echo %%i. !FILENAME_%%i!
)

:: 让用户选择文件
echo.
set /p "CHOICE=Please select a file number (1-%FILE_COUNT%): "

:: 验证用户输入
if "%CHOICE%"=="" (
    echo.
    echo ======================================
    echo Invalid selection - Empty input
    echo ======================================
    echo Press any key to exit...
    pause >nul
    exit /b 1
)

:: 检查选择是否在有效范围内
if %CHOICE% LSS 1 (
    echo.
    echo ======================================
    echo Invalid selection - Number too small
    echo ======================================
    echo Valid range: 1-%FILE_COUNT%
    echo Press any key to exit...
    pause >nul
    exit /b 1
)
if %CHOICE% GTR %FILE_COUNT% (
    echo.
    echo ======================================
    echo Invalid selection - Number too large
    echo ======================================
    echo Valid range: 1-%FILE_COUNT%
    echo Press any key to exit...
    pause >nul
    exit /b 1
)

:: 获取选择的文件
set "SELECTED_PATH=!FILE_%CHOICE%!"
set "SELECTED_FILE=!FILENAME_%CHOICE%!"

echo.
echo Selected file: %SELECTED_FILE%
echo File path: %SELECTED_PATH%

:: 生成输出文件路径（使用延迟变量展开处理空格和特殊字符）
set "OUTPUT_FILE=!SELECTED_PATH:.webm=.mp4!"

:: 检查 ffmpeg 是否可用
echo Checking ffmpeg availability...
set "FFMPEG_PATH=C:\Applications\ffmpeg\bin\ffmpeg.exe"

if exist "%FFMPEG_PATH%" (
    set "FFMPEG_CMD=%FFMPEG_PATH%"
) else (
    :: 尝试在系统路径中查找
    where ffmpeg >nul 2>&1
    if !errorlevel! equ 0 (
        set "FFMPEG_CMD=ffmpeg"
    ) else (
        echo.
        echo ======================================
        echo ERROR: ffmpeg not found
        echo ======================================
        echo ffmpeg.exe not found in system PATH or default location
        echo Please ensure ffmpeg is installed and added to system PATH
        echo.
        echo Press any key to exit...
        pause >nul
        exit /b 1
    )
)

:: 执行转换
echo.
echo Converting file: !SELECTED_PATH!
echo Output file: !OUTPUT_FILE!
echo.

"!FFMPEG_CMD!" -y -i "!SELECTED_PATH!" -c:v libx264 -c:a aac "!OUTPUT_FILE!"

:: 检查转换结果
if exist "!OUTPUT_FILE!" (
    echo.
    echo ======================================
    echo Conversion completed successfully!
    echo ======================================
    echo Output file: !OUTPUT_FILE!
    echo.
) else (
    echo.
    echo ======================================
    echo Conversion failed!
    echo ======================================
    echo Please check the output above for error details.
    echo.
)

echo.
echo ======================================
echo Script execution completed.
echo Press any key to close this window...
echo ======================================
pause >nul
echo.