Script for resampling a whole directory of music files recursively. Depends on ffmpeg (better build it with soxr)

gistfile1.php

<?php

/* config section { */

$input = "F:\\Music";
$output = "F:\\ResampledMusic";

// it will convert all the files to flacs
$ffmpegExecutable = "C:\\users\\nikita\\bin\\ffmpeg";
$ffmpegOptions = "-af aresample=resampler=soxr -ar 44100";
$inputAvailableExtensions = ["flac", "wav", "ape"];
$extensionToCopy = ["cue"];

/* config section } */

/* logic { */

$toConvert = [];
$toCopy = [];
foreach (getFlatFileTree($input) as $file) {
	if (in_array(strtolower($file->getExtension()), $inputAvailableExtensions) && ! file_exists(getNewFilename($input, $output, $file))) {
		$toConvert[] = $file;
	} elseif (in_array(strtolower($file->getExtension()), $extensionToCopy) && ! file_exists(str_replace($input, $output, $file->getPathname()))) {
		$toCopy[] = $file;
	}
}

echo "There's ", count($toConvert), " files to convert and ", count($toCopy), " to copy...", "\r\n";

foreach ($toCopy as $from) {
	$to = str_replace($input, $output, $from->getPathname());
	$dir = dirname($to);

	if ( ! file_exists($dir)) {
		mkdir($dir, 0777, true);
	}

	copy($from->getPathname(), $to);
}

echo "All ", count($toCopy), " files were copied. Starting convertation:\r\n";

foreach ($toConvert as $from) {
	$to = getNewFilename($input, $output, $from);
	$dir = dirname($to);

	if ( ! file_exists($dir)) {
		mkdir($dir, 0777, true);
	}

	echo "\r\n\r\nConverting file ", $from->getPathname(), "\r\n\r\n";
	exec($ffmpegExecutable . " -i \"" . $from->getPathname() . "\" " . $ffmpegOptions . " \"" . $to . "\"");
}

/* logic } */

function getFlatFileTree($dir)
{
	$dir = new RecursiveDirectoryIterator($dir);

	$files = [];
	foreach ($dir as $file) {
		if ($file->getFilename() === "." || $file->getFilename() === "..") {
			continue;
		}

		if ($file->isDir()) {
			$files = array_merge($files, getFlatFileTree($file->getPathname()));
		} else {
			$files[] = $file;
		}
	}

	return $files;
}

function getNewFilename($input, $output, SplFileInfo $file)
{
	global $inputAvailableExtensions;

	$f = str_replace($input, $output, $file->getPathname());
	$f = str_replace($inputAvailableExtensions, "flac", $f);

	return $f;
}