ConvertPdfsToPngs.ps1

# Converts PDF file passed into script into PNG files. Requires Ghostscript to be installed.
# Based on https://github.com/DeadExecutive/pdf_to_png/blob/main/PDF_To_PNG.ps1
#
# To enable drag and drop files, create a desktop shortcut with this command:
#    powershell.exe -noprofile -noexit -File "C:\Path\To\ConvertPDFToPNGs.ps1"

# Input PDF path as an argument
param (
    [Parameter(ValueFromRemainingArguments=$true)]
    $pdfPath
)

# Output directory for PNG files
$outputDirectory = Join-Path $env:USERPROFILE 'Documents'

# Check if a PDF path is provided
if (-not $pdfPath) {
    Write-Host "Please drag a PDF onto this script." -ForegroundColor Yellow
    Exit
}

# Extract the name of the pdf file without extension
$pdfName = [System.IO.Path]::GetFileNameWithoutExtension($pdfPath)

# Create the directory for PNG files with name of PDF
$finalOutputDirectory = "$outputDirectory\$pdfName"

$gsPath = Join-Path $env:ProgramFiles 'gs\gs10.02.1\bin\gswin64c.exe'

# Check if Ghostscript is installed
if (-Not (Test-Path ($gsPath))) {
    Write-Host "Ghostscript is not installed or could not be found on this system."
    Write-Host "Please install Ghostscript and try again."
    Exit
}

# Ensure the output directory exists
if (-Not (Test-Path -Path $finalOutputDirectory)) {
    New-Item -ItemType Directory -Force -Path $finalOutputDirectory | Out-Null
}

# Ghostscript commandline args
$arguments = @(
    "-q",                                                # Quiet mode
    "-dSAFER",                                           # Enables a safer mode
    "-dBATCH",                                           # Batch mode
    "-dNOPAUSE",                                         # Don't pause between pages
    "-sDEVICE=pngalpha",                                 # Sets the output to an alpha channeled PNG
    "-r300",                                             # Sets resolution to 300 DPI
    "-dTextAlphaBits=4",                                 # Improves text output
    "-dGraphicsAlphaBits=4",                             # Improves graphics output
    "-sOutputFile=`"$finalOutputDirectory\Slide%03d.png`"",   # Output file pattern
    "`"$pdfPath`""
)

# Run Ghostscript to convert PDF to PNGs
$gsProcess = Start-Process -FilePath ($gsPath) -ArgumentList $arguments -NoNewWindow -PassThru

# Wait for Ghostscript to finish
$gsProcess.WaitForExit()

# Display a success message
Write-Host "PDF $pdfPath converted to PNG files in $finalOutputDirectory"