blue-twilight/app/Helpers/ImageHelper.php

<?php

namespace App\Helpers;

use App\AlbumSources\IAlbumSource;
use App\Photo;

class ImageHelper
{
    public function generateThumbnail($gdImageResource, Photo $photo, $thumbnailInfo)
    {
        $thumbnailWidth = intval($thumbnailInfo['width']);
        $thumbnailHeight = intval($thumbnailInfo['height']);

        // If image is portrait, restrict the height by the relevant aspect ratio
        if ($photo->height > $photo->width)
        {
            $aspectRatio = $photo->height / $photo->width;
            $thumbnailWidth = intval($thumbnailInfo['height']) / $aspectRatio;
            $thumbnailHeight = intval($thumbnailInfo['height']);
        }

        $thumbnailImageResource = imagecreatetruecolor($thumbnailWidth, $thumbnailHeight);

        imagecopyresized(
            $thumbnailImageResource,
            $gdImageResource,
            0,
            0,
            0,
            0,
            $thumbnailWidth,
            $thumbnailHeight,
            $photo->width,
            $photo->height
        );

        // TODO make the /tmp folder configurable
        $tempName = tempnam('/tmp', 'btw_thumb_');
        $tempNameWithExtension = ($tempName . '.jpg');
        rename($tempName, $tempNameWithExtension);

        // TODO make thumbnail quality configurable
        imagejpeg($thumbnailImageResource, $tempNameWithExtension, 90);

        return $tempNameWithExtension;
    }

    public function openImage($imagePath, &$imageInfo)
    {
        $imageInfo = getimagesize($imagePath);

        if ($imageInfo === false)
        {
            throw new \Exception(sprintf('The image "%s" does not appear to be a valid image, or cannot be read', pathinfo($imagePath, PATHINFO_FILENAME)));
        }

        $im = false;
        $type = $imageInfo[2];
        $allowedTypes = [
            IMG_GIF,
            IMG_PNG,
            IMG_JPEG,
            IMG_WBMP
        ];

        if (!in_array($type, $allowedTypes))
        {
            return false;
        }

        switch ($type)
        {
            case IMG_GIF:
                $im = imagecreatefromgif($imagePath);
                break;

            case IMG_JPEG:
                $im = imagecreatefromjpeg($imagePath);
                break;

            case IMG_PNG:
                $im = imagecreatefrompng($imagePath);
                break;

            case IMG_WBMP:
                $im = imagecreatefromwbmp($imagePath);
                break;
        }

        return $im;
    }

    public function rotateImage($imageResource, $angle)
    {
        imagesetinterpolation($imageResource, IMG_SINC);

        return imagerotate($imageResource, $angle, 0);
    }
}