image resizer php with crop and auto padding

resize.php

<?php
// TODO create uploads/cache folder
public static function resize($path, $w, $h)
    {
        $path = ltrim($path, '/');

        if (!file_exists(public_path($path))) {
            $path = "uploads/placeholder.png";
        }

        $pos = strrpos($path, '.');
        if ($pos === false) {
            return $path;
        }

        $ext = substr($path, $pos);
        $suffix = '_' . $w . '_' . $h . $ext;
        $path_cache = str_replace($ext, '', $path);
        $path_cache = str_replace('uploads', 'uploads/cache', $path_cache) . $suffix;
        if (file_exists($path_cache)) {
            return $path_cache;
        }

        $full_path = public_path($path);
        $full_path_cache = public_path($path_cache);

        $image = '';
        $image_type = '';
        // get image info about this file
        $image_info = getimagesize($full_path);
        // load file depending on mimetype
        try {
            switch ($image_info["mime"]) {
                case "image/gif"  :
                    $image_type = 'gif';
                    $image = @imagecreatefromgif($full_path);
                    break;
                case "image/jpeg" :
                    $image_type = 'jpg';
                    $image = @imagecreatefromjpeg($full_path);
                    break;
                case "image/png" :
                    $image_type = 'png';
                    $image = @imagecreatefrompng($full_path);
                    break;
            }
        } catch (Exception $e) {
            Log::error('Exception loading ' . $full_path . ' - ' . $e->getMessage());
            $path = "uploads/placeholder.png";
            return $path;
        }

        // calc new dimensions
        $image_width = imageSX($image);
        $image_height = imageSY($image);
        if ($image_width > $w || $image_height > $h) {
            if (($image_width / $image_height) > ($w / $h)) {
                $tnw = $w;
                $tnh = $tnw * $image_height / $image_width;
            } else {
                $tnh = $h;
                $tnw = $tnh * $image_width / $image_height;
            }
        } else {
            $tnw = $image_width;
            $tnh = $image_height;
        }
        // create a temp based on new dimensions
        $tx = $w;
        $ty = $h;
        $px = ($w - $tnw) / 2;
        $py = ($h - $tnh) / 2;
        $temp_image = imagecreatetruecolor($tx, $ty);

        // if padding, fill background
        if ($image_type == 'png') {
            imagealphablending($temp_image, false);
            imagesavealpha($temp_image, true);
            $color = imagecolorallocatealpha($temp_image, 0, 0, 0, 127);
            imagefilledrectangle($temp_image, 0, 0, $tx, $ty, $color);

        } else {
            $col = [255, 255, 255];
            $bg = imagecolorallocate($temp_image, $col[0], $col[1], $col[2]);
            imagefilledrectangle($temp_image, 0, 0, $tx, $ty, $bg);
        }

        // copy resized
        imagecopyresampled($temp_image, $image, $px, $py, 0, 0, $tnw, $tnh, $image_width,
            $image_height);
        switch ($image_type) {
            case "gif"  :
                imagegif($temp_image, $full_path_cache);
                break;
            case "jpg" :
                imagejpeg($temp_image, $full_path_cache, 75);
                break;
            case "png" :
                imagepng($temp_image, $full_path_cache);
                break;
        }

        return $path_cache;
    }