Sulu\Bundle\MediaBundle\Media\ImageConverter\MediaImageExtractor::extract PHP Method

    public function extract($content)
    {
        $finfo = new \finfo();
        $mimeType = $finfo->buffer($content, FILEINFO_MIME_TYPE);
        if ($mimeType === 'application/pdf') {
            return $this->convertPdfToImage($content);
        }
        if ($mimeType === 'image/vnd.adobe.photoshop') {
            return $this->convertPsdToImage($content);
        }
        if ($mimeType === 'image/svg+xml') {
            return $this->convertSvgToImage($content);
        }
        if (fnmatch('video/*', $mimeType)) {
            return $this->convertVideoToImage($content);
        }
        return $content;
    }