A PowerShell script to convert JSON files generated by Google Photos Takeout to XMP sidecar files to be used in Immich (with external libraries)

JSONtoXMP.ps1

<#
.DESCRIPTION
Converts Google Photos Takeout JSON files to XMP sidecar files for Immich
    - Prompts for a folder containing photos & JSON via a FolderBrowserDialog
    - Logs errors/exceptions to JSONroXMP.log (in the same directory as this script)
    - Prompts once to overwrite or skip existing XMP files
    - Replaces placeholders in the XMP template with actual values from the JSON

.NOTES
    Author: Maksim-us
    Version: 1.0
#>

# ------------------------------------------------------------------------------
# Load the .NET assembly for Windows.Forms (for the folder dialog)
# ------------------------------------------------------------------------------
[System.Reflection.Assembly]::LoadWithPartialName("System.Windows.Forms") | Out-Null

# ------------------------------------------------------------------------------
# Prompt user to pick a folder
# ------------------------------------------------------------------------------
$folderBrowser = New-Object System.Windows.Forms.FolderBrowserDialog
$folderBrowser.Description = "Select the root folder containing your photos and JSON files."
$folderBrowser.ShowNewFolderButton = $false

$dialogResult = $folderBrowser.ShowDialog()
if ($dialogResult -ne [System.Windows.Forms.DialogResult]::OK) {
    Write-Host "Folder selection canceled by user. Exiting script."
    return
}

# The user-selected folder
$photoDir = $folderBrowser.SelectedPath

# ------------------------------------------------------------------------------
# Determine where this script lives
# ------------------------------------------------------------------------------
$scriptDir = Split-Path $MyInvocation.MyCommand.Path -Parent
if (-not $scriptDir) {
    $scriptDir = Split-Path $PSCommandPath -Parent
}

# ------------------------------------------------------------------------------
# Prepare error log file (only errors will go here)
# ------------------------------------------------------------------------------
$logFile = Join-Path $scriptDir "JSONroXMP.log"
If (Test-Path $logFile) { Remove-Item $logFile -ErrorAction SilentlyContinue }

# ------------------------------------------------------------------------------
# Display header to console
# ------------------------------------------------------------------------------
Write-Host "============================================================="
Write-Host " Google Photos JSON → XMP Converter"
Write-Host "============================================================="
Write-Host "Script directory: $scriptDir"
Write-Host "Photo directory : $photoDir"
Write-Host ""

# ------------------------------------------------------------------------------
# Ask if existing XMP files should be overwritten or skipped
# ------------------------------------------------------------------------------
$overwriteChoice = Read-Host "If an XMP file already exists, Overwrite (O) or Skip (S)? [O/S]"
$overwriteChoice = $overwriteChoice.ToUpper()
while ($overwriteChoice -notin @("O","S")) {
    Write-Host "Invalid selection. Please enter 'O' or 'S'."
    $overwriteChoice = Read-Host "If an XMP file already exists, Overwrite (O) or Skip (S)? [O/S]"
    $overwriteChoice = $overwriteChoice.ToUpper()
}
Write-Host "`nYou selected: $overwriteChoice"

# ------------------------------------------------------------------------------
# Counters for summary
# ------------------------------------------------------------------------------
$processedCount = 0
$createdCount   = 0
$skippedCount   = 0

# ------------------------------------------------------------------------------
# Function: Generate correct XMP filename
# ------------------------------------------------------------------------------
function Get-XmpFileName {
    param(
        [string]$jsonBaseName  # the filename after removing .json
    )
# some files do not have the correct .jpg.json extension (just .json) this will add ".jpg" if any of the below are not present. Need to be reworked
    $commonImageExts = @("jpg","jpeg","png","gif","heic","tif","tiff","bmp","avi","mp4","mov")
    $regexPattern    = "^(.*)\.(" + ($commonImageExts -join "|") + ")\((\d+)\)$"

    if ($jsonBaseName -match $regexPattern) {
        # Rebuild: prefix(counter).extension
        $prefix    = $Matches[1]
        $extension = $Matches[2]
        $counter   = $Matches[3]
        return "$prefix($counter).$extension.xmp"
    }
    else {
        # Check if base name ends with a recognized extension
        $endsWithExt = $false
        foreach ($ext in $commonImageExts) {
            if ($jsonBaseName.ToLower().EndsWith(".$ext")) {
                $endsWithExt = $true
                break
            }
        }
        # If no recognized extension, append ".jpg"
        if (-not $endsWithExt) {
            $jsonBaseName += ".jpg"
        }
        return "$jsonBaseName.xmp"
    }
}

# ------------------------------------------------------------------------------
# MAIN PROCESS
# ------------------------------------------------------------------------------
if (-not (Test-Path $photoDir)) {
    Write-Host "ERROR: Directory does not exist: $photoDir"
    return
}

Get-ChildItem -Path $photoDir -Filter "*.json" -Recurse | ForEach-Object {
    $processedCount++

    $jsonFile    = $_.FullName
    $jsonData    = Get-Content $jsonFile -Raw | ConvertFrom-Json
    $currentDir  = $_.DirectoryName
    $jsonBaseName = $_.BaseName

    # Determine final XMP filename
    $xmpName = Get-XmpFileName -jsonBaseName $jsonBaseName
    $xmpFile = Join-Path $currentDir $xmpName

    # Overwrite or skip logic
    if ((Test-Path $xmpFile) -and ($overwriteChoice -eq "S")) {
        Write-Host "Skipping existing XMP file: $xmpFile"
        $skippedCount++
        return
    }

    # Convert Unix timestamp to date
    $unixTimestamp = $jsonData.photoTakenTime.timestamp
    $dateTime      = (Get-Date "1970-01-01 00:00:00.000Z").AddSeconds($unixTimestamp)
    $xmpDate       = $dateTime.ToString("yyyy:MM:dd HH:mm:ss")

    # Build optional GPS string
    $lat = $jsonData.geoData.latitude
    $lng = $jsonData.geoData.longitude
    $gpsString = ""

    if (($lat -ne 0) -or ($lng -ne 0)) {
        $latRef = if ($lat -ge 0) { "N" } else { "S" }
        $lngRef = if ($lng -ge 0) { "E" } else { "W" }

        $absLat  = [Math]::Abs($lat)
        $absLng  = [Math]::Abs($lng)
        $latDeg  = [Math]::Floor($absLat)
        $latMin  = ($absLat - $latDeg) * 60
        $lngDeg  = [Math]::Floor($absLng)
        $lngMin  = ($absLng - $lngDeg) * 60

        # Insert placeholders, then replace them
        $gpsString = @'
  <rdf:Description rdf:about=""
    xmlns:exif="http://ns.adobe.com/exif/1.0/">
    <exif:GPSLatitude>LAT_DEG,LAT_MINLAT_REF</exif:GPSLatitude>
    <exif:GPSLatitudeRef>LAT_REF</exif:GPSLatitudeRef>
    <exif:GPSLongitude>LNG_DEG,LNG_MINLNG_REF</exif:GPSLongitude>
    <exif:GPSLongitudeRef>LNG_REF</exif:GPSLongitudeRef>
  </rdf:Description>
'@

        $gpsString = $gpsString.Replace("LAT_DEG",  $latDeg)
        $gpsString = $gpsString.Replace("LAT_MIN",  $latMin.ToString("0.000000"))
        $gpsString = $gpsString.Replace("LAT_REF",  $latRef)
        $gpsString = $gpsString.Replace("LNG_DEG",  $lngDeg)
        $gpsString = $gpsString.Replace("LNG_MIN",  $lngMin.ToString("0.000000"))
        $gpsString = $gpsString.Replace("LNG_REF",  $lngRef)
    }

    # Main XMP content (single-quoted here-string)
    $xmpContent = @'
<?xml version="1.0" encoding="UTF-8"?>
<x:xmpmeta xmlns:x="adobe:ns:meta/" x:xmptk="XMP Core 6.0.0">
  <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
    <rdf:Description rdf:about=""
      xmlns:xmp="http://ns.adobe.com/xap/1.0/"
      xmlns:dc="http://purl.org/dc/elements/1.1/"
      xmlns:photoshop="http://ns.adobe.com/photoshop/1.0/"
      xmlns:xmpMM="http://ns.adobe.com/xap/1.0/mm/"
      xmlns:exif="http://ns.adobe.com/exif/1.0/">
      <xmp:CreateDate>XMP_DATE</xmp:CreateDate>
      <xmp:ModifyDate>XMP_DATE</xmp:ModifyDate>
      <xmp:MetadataDate>XMP_DATE</xmp:MetadataDate>
      <dc:title>
        <rdf:Alt>
          <rdf:li xml:lang="x-default">JSON_TITLE</rdf:li>
        </rdf:Alt>
      </dc:title>
      <dc:description>
        <rdf:Alt>
          <rdf:li xml:lang="x-default">JSON_DESCRIPTION</rdf:li>
        </rdf:Alt>
      </dc:description>
      <photoshop:DateCreated>XMP_DATE</photoshop:DateCreated>
      <exif:DateTimeOriginal>XMP_DATE</exif:DateTimeOriginal>
    </rdf:Description>
    GPS_BLOCK
  </rdf:RDF>
</x:xmpmeta>
'@

    # Replace placeholders (literal string replacement)
    $xmpContent = $xmpContent.Replace("XMP_DATE", $xmpDate)
    $xmpContent = $xmpContent.Replace("JSON_TITLE", $jsonData.title)
    $xmpContent = $xmpContent.Replace("JSON_DESCRIPTION", $jsonData.description)

    if ($gpsString) {
        $xmpContent = $xmpContent.Replace("GPS_BLOCK", $gpsString)
    }
    else {
        $xmpContent = $xmpContent.Replace("GPS_BLOCK", "")
    }

    # Write out the XMP file
    $xmpContent | Out-File -FilePath $xmpFile -Encoding UTF8
    $createdCount++

    Write-Host "Created XMP file: $xmpFile"
}

Write-Host "`n============================================================="
Write-Host "Processing complete!"
Write-Host "Total JSON files processed: $processedCount"
Write-Host "Total XMP files created   : $createdCount"
Write-Host "Total XMP files skipped   : $skippedCount"
Write-Host "============================================================="

# ------------------------------------------------------------------------------
# Check if any errors occurred during the run
# If so, write them to JSONtoXMP.log
# ------------------------------------------------------------------------------
if ($Error.Count -gt 0) {
    # Prepend a note to the log
    "PowerShell encountered $($Error.Count) error(s) while running this script:" | Out-File $logFile
    # Write each error line
    $Error | Out-File -Append $logFile
    Write-Host "`nERRORS occurred. See `"$logFile`" for details."
} else {
    Write-Host "`nNo errors occurred."
}