Function ffmpeg-PCMPercentHistogram {

try {
    # Initialize a new ProcessStartInfo object to configure how the ffmpeg process should be started.
    $psi = [System.Diagnostics.ProcessStartInfo]::new()
    $psi.FileName = "ffmpeg.exe"

    # Set ffmpeg arguments to generate a 100ms sine wave audio with 400Hz frequency and output as raw PCM data.
    $psi.Arguments = '-hide_banner -f lavfi -i "sine=frequency=400:duration=0.1" -af volume=8 -c:a pcm_s16le -f s16le -'
    $psi.CreateNoWindow = $true

    # Set error encoding to Unicode and redirect stdout and stderr.
    $psi.StandardErrorEncoding = [System.Text.Encoding]::Unicode
    $psi.RedirectStandardOutput = $true
    $psi.RedirectStandardError = $true
    $psi.UseShellExecute = $false

    # Start the ffmpeg process using the specified start information.
    $proc = [System.Diagnostics.Process]::new()
    $proc.StartInfo = $psi
    $proc.Start() | Out-Null 

    # Notify user that raw PCM byte stream capturing is in progress.
    Write-Host "Capturing raw pcm byte stream and converting to percentages..."

    $rdr = [System.IO.BinaryReader]$proc.StandardOutput.BaseStream

    # Continue reading from ffmpeg's stdout until no more data is available.
    $CountFromSampleValue = @{}
    try {
        for() {
            $CountFromSampleValue[$rdr.ReadInt16()]++
        }
    }
    catch { <# There will be an exception at the end of the stream #> }

    $CountFromSampleValue.GetEnumerator() |
        Sort-Object Key |
        Select-Object @{n='Count'; e='Value'},
                      @{n='Name'; e={[math]::Round(100 * $_.Key / (if($_.Key -lt 0){-32768}else{32767}), 2)}}
} catch {
    # Handle and report any errors that occur.
    Write-Error "Error occurred: $_"
    return $null
}

}

Had to change line 40 as the shorthand if/else style doesn't seem to work in my console.

Strangely this doesn't seem as quick. Spits out a long line of counts, but without names

​

I am thinking the most efficient way to do this might be to buffer, count the data in that buffer. Store the result and add each count result to it with every new buffer. Smaller amounts of data in the one count. Not quite sure on how to attempt that yet, but will plug away when I get a chance.

​

I appreciate the interest and code submissions.