PowerShell 技能连载 - 音频处理技巧

在 PowerShell 中处理音频文件是一项有趣的任务，本文将介绍一些实用的音频处理技巧。

首先，让我们看看基本的音频操作：

# 创建音频信息获取函数
function Get-AudioInfo {
    param(
        [string]$AudioPath
    )
    
    try {
        # 使用 ffprobe 获取音频信息
        $ffprobe = "ffprobe"
        $info = & $ffprobe -v quiet -print_format json -show_format -show_streams $AudioPath | ConvertFrom-Json
        
        return [PSCustomObject]@{
            FileName = Split-Path $AudioPath -Leaf
            Duration = [math]::Round([double]$info.format.duration, 2)
            Size = [math]::Round([double]$info.format.size / 1MB, 2)
            Bitrate = [math]::Round([double]$info.format.bit_rate / 1000, 2)
            Format = $info.format.format_name
            Channels = ($info.streams | Where-Object { $_.codec_type -eq "audio" }).channels
            SampleRate = ($info.streams | Where-Object { $_.codec_type -eq "audio" }).sample_rate
        }
    }
    catch {
        Write-Host "获取音频信息失败：$_"
    }
}

音频格式转换：

# 创建音频格式转换函数
function Convert-AudioFormat {
    param(
        [string]$InputPath,
        [string]$OutputPath,
        [ValidateSet("mp3", "wav", "ogg", "aac")]
        [string]$TargetFormat,
        [ValidateSet("high", "medium", "low")]
        [string]$Quality = "medium"
    )
    
    try {
        $ffmpeg = "ffmpeg"
        $qualitySettings = @{
            "high" = "-q:a 0"
            "medium" = "-q:a 4"
            "low" = "-q:a 8"
        }
        
        $command = "$ffmpeg -i `"$InputPath`" $($qualitySettings[$Quality]) `"$OutputPath`""
        Invoke-Expression $command
        
        Write-Host "格式转换完成：$OutputPath"
    }
    catch {
        Write-Host "转换失败：$_"
    }
}

音频剪辑：

# 创建音频剪辑函数
function Split-AudioFile {
    param(
        [string]$InputPath,
        [string]$OutputFolder,
        [double]$StartTime,
        [double]$Duration
    )
    
    try {
        $ffmpeg = "ffmpeg"
        $fileName = [System.IO.Path]::GetFileNameWithoutExtension($InputPath)
        $extension = [System.IO.Path]::GetExtension($InputPath)
        $outputPath = Join-Path $OutputFolder "$fileName`_split$extension"
        
        $command = "$ffmpeg -i `"$InputPath`" -ss $StartTime -t $Duration `"$outputPath`""
        Invoke-Expression $command
        
        Write-Host "音频剪辑完成：$outputPath"
    }
    catch {
        Write-Host "剪辑失败：$_"
    }
}

音频合并：

# 创建音频合并函数
function Merge-AudioFiles {
    param(
        [string[]]$InputFiles,
        [string]$OutputPath
    )
    
    try {
        $ffmpeg = "ffmpeg"
        $tempFile = "temp_concat.txt"
        
        # 创建临时文件列表
        $InputFiles | ForEach-Object {
            "file '$_'" | Out-File -FilePath $tempFile -Append
        }
        
        # 合并音频文件
        $command = "$ffmpeg -f concat -safe 0 -i $tempFile -c copy `"$OutputPath`""
        Invoke-Expression $command
        
        # 删除临时文件
        Remove-Item $tempFile
        
        Write-Host "音频合并完成：$OutputPath"
    }
    catch {
        Write-Host "合并失败：$_"
    }
}

音频效果处理：

# 创建音频效果处理函数
function Apply-AudioEffect {
    param(
        [string]$InputPath,
        [string]$OutputPath,
        [ValidateSet("normalize", "fade", "echo", "reverb")]
        [string]$Effect,
        [hashtable]$Parameters
    )
    
    try {
        $ffmpeg = "ffmpeg"
        $effectSettings = @{
            "normalize" = "-af loudnorm"
            "fade" = "-af afade=t=in:st=0:d=$($Parameters.Duration)"
            "echo" = "-af aecho=0.8:0.88:60:0.4"
            "reverb" = "-af aecho=0.8:0.9:1000:0.3"
        }
        
        $command = "$ffmpeg -i `"$InputPath`" $($effectSettings[$Effect]) `"$OutputPath`""
        Invoke-Expression $command
        
        Write-Host "效果处理完成：$OutputPath"
    }
    catch {
        Write-Host "效果处理失败：$_"
    }
}

这些技巧将帮助您更有效地处理音频文件。记住，在处理音频时，始终要注意文件格式的兼容性和音频质量。同时，建议在处理大型音频文件时使用流式处理方式，以提高性能。