Powershell script to convert all .jpg in a folder to .webp

convert_all_jpg_in_folder_to_webp.ps1

# Set the desired quality (0 to 100). 80 is a good default balance.
$Quality = 80

# --- User Configuration ---

# 1. Define the directory where the conversion should start.
#    '.' means the current directory where the script is run.
$StartFolder = "." 

# 2. Define the path to the cwebp executable.
#    - If it's in your system's PATH, just use 'cwebp'.
#    - Otherwise, provide the full path, e.g., 'C:\WebPTools\bin\cwebp.exe'.
$cwebpPath = "cwebp" 

# --- Script Logic ---

Write-Host "--- Starting WebP Conversion Script ---" -ForegroundColor Yellow
Write-Host "Target Folder: $(Resolve-Path $StartFolder)" -ForegroundColor Cyan
Write-Host "Quality Setting: $Quality" -ForegroundColor Cyan
Write-Host "cwebp Path: $cwebpPath" -ForegroundColor Cyan

# Check if cwebp is available
if (-not (Get-Command $cwebpPath -ErrorAction SilentlyContinue)) {
    Write-Host "ERROR: cwebp executable not found at '$cwebpPath'." -ForegroundColor Red
    Write-Host "Please ensure cwebp is in your system's PATH or update the `$cwebpPath variable." -ForegroundColor Red
    exit 1
}

# Recursively find all .jpg files
$FilesToConvert = Get-ChildItem -Path $StartFolder -Filter "*.jpg" -Recurse -File

if ($FilesToConvert.Count -eq 0) {
    Write-Host "No .jpg files found to convert." -ForegroundColor Green
    exit 0
}

Write-Host "Found $($FilesToConvert.Count) JPG file(s). Starting conversion..." -ForegroundColor Green

# Loop through each file and run cwebp
foreach ($File in $FilesToConvert) {
    # Define the output file path (changes the extension to .webp)
    $OutputFilePath = Join-Path -Path $File.DirectoryName -ChildPath "$($File.BaseName).webp"
    
    Write-Host "Converting: $($File.Name) --> $($OutputFilePath)" -ForegroundColor White

    # Execute the cwebp command
    & $cwebpPath -q $Quality "$($File.FullName)" -o "$OutputFilePath"

    # Optional: Check the exit code of the cwebp command
    if ($LASTEXITCODE -ne 0) {
        Write-Host "WARNING: cwebp returned an error code ($LASTEXITCODE) for $($File.Name)." -ForegroundColor Yellow
    }
}

Write-Host "--- Conversion Complete! ---" -ForegroundColor Green