建议调整图像大小，直到满足所需的文件大小

Question

目前有一个简单的功能，但它允许用户添加大图像。我想允许所有图片上传，但是应该有一个功能可以调整图片的大小，直到满足特定的文件大小（例如小于 200kb）

if($_FILES['file']['size'] != 0){

        $uploadOk = 0;

        //image object
        $image = $_FILES['file'];

        //create unique name for file
        $imageRandomName = substr(md5(time()), 0, 5) . "-" . $image['name'];

        //upload dir
        $target_dir = "rest/user" . $_SESSION["username"] . "/events/" . $_SESSION["event_id"] . "/people/";

        //make folder for user if non exists
        if(!file_exists($target_dir)){
            mkdir($target_dir, 0777, true);
        }

        //file to be upload
        $target_file = $target_dir . base($imageRandomName);

        //get file type
        $imageFileType = pathinfo($target_file, PATHINFO_EXTENSION);

        $check = getimagesize($image["tmp_name"]);

        if($check !== false){
            $uploadOk = 1;

        } else {
            $uploadOk = 0;
        }

        if($uploadOk == 0){

            echo "noupload";

        } else {

            if ( move_uploaded_file($image["tmp_name"], $target_file ) ) {

                 //get file size on server
                $filesizeonserver = filesize($target_file);
                echo "file: ".$target_file." size: ".$filesizeonserver;
                $times = 0;
                if($filesizeonserver > 100000){
                    do{
                        $resized = resizeImage($target_file, "0.1");
                        $filesizeonserver = filesize($target_file);
                        $times++;    
                    } while ($filesizeonserver > 100000);
                    echo "resized ".$times." times";
                } else {

                }


                //mysql query

            } else {

                echo "Sorry, there was an error uploading your file.";

            }
        }
    } else {
        //do mysql query
    }

resizeImage()

function resizeImage($file, $percent){
    list($width, $height) = getimagesize($file);
    $newwidth = $width-($width*$percent);
    $newheight = $height-($height*$percent);
    $thumb = imagecreatetruecolor($newwidth, $newheight);
    $source = imagecreatefromjpeg($file);
    imagecopyresized($thumb, $source, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);
    $newImage = imagejpeg($thumb, $file, 100);
    return $newImage;
}

现在我已经到了某个地方，我想我真的很接近实现它，但出于某种奇怪的原因，我得到的图像尺寸为 1px 宽、4px 高和 4kb 大小。全黑图像。

如果您正在考虑将什么图像添加到此功能： 1,232,055 字节，1220 × 1829，72dpi，JPEG

编辑：好的，现在我认为 resizeImage 函数有问题。因为它只在第一次时才起作用。由于某种原因，它无法获取图像并将其呈现为黑色和微小的。

EDIT2：现在我正在获得图像大小调整功能，它没有任何问题。我注意到该功能会不断调整图像的大小，直到苦尽甘来。我可以在查找它的收缩方式中看到它。

EDIT3：我找到了问题所在。现在看来 $filesizeonserver 总是得到第一个值并且在做......虽然它没有更新，即使你将它设置为更改。

Answer 1

$allowedFileTypes = ['image/png', 'image/gif', 'image/jpeg', 'image/jpg'];

        if (in_array($_FILES['image']['type'], $allowedFileTypes)) {
            $imageType = $_FILES['image']['type'];
            //allow file size under 10mb
            if($_FILES['file']['size'] < 10000000){

                //image object
                $image = $_FILES['file'];

                //so there is no same name files
                $imageRandomName = substr( md5( time() ), 0, 5 ) . "-" . $image['name'];

                //place where image is uploaded
                $target_dir = 'rest/user/' . $_SESSION['username'] . '/events/' . $_SESSION['event_id'] . '/people/';

                //make folder for users
                if ( !file_exists( $target_dir ) ) {
                    mkdir( $target_dir, 0777, true );
                }

                //file to be uploded
                $target_file = $target_dir . basename( $imageRandomName );

                //get file type
                //$imageFileType = pathinfo( $target_file, PATHINFO_EXTENSION );

                $check = getimagesize($image["tmp_name"]);

                if ($check !== false) {
                    echo "File is an image - " . $check["mime"] . ".";
                    $uploadOk = 1;
                } else {
                    echo "File is not an image.";
                    $uploadOk = 0;
                }

                //check if upload is ok
                if ( $uploadOk == 0 ) {
                    echo "Sorry cant upload";
                } else {
                    if ( move_uploaded_file($image["tmp_name"], $target_file ) ) {


                        //get file size on server
                        $filesizeonserver = filesize($target_file);

                        $times = 0;

                        if($filesizeonserver > 300000){
                            do{
                                clearstatcache(); 
                                $resized = resizeImage($target_file, 0.05, $imageType);
                                $filesizeonserver = filesize($target_file);
                                $times++;    
                            } while ($filesizeonserver > 300000);
                            echo "resized ".$times." times";
                        } else {

                        }

                        //sql query

                    } else {
                        echo "Sorry, there was an error uploading your file.";
                    }
                }

            } else {
                //sql query
            }   
        } else {
            echo "wrongimagetype";
        }

resizeImage()

function resizeImage($file, $percent, $imageType){

    list($width, $height) = getimagesize($file);
    $newwidth = $width-($width*$percent);
    $newheight = $height-($height*$percent);

    $thumb = imagecreatetruecolor($newwidth, $newheight);

    switch($imageType){
        case 'image/png': 
            $background = imagecolorallocate($thumb, 0, 0, 0);
            imagecolortransparent($thumb, $background);
            imagealphablending($thumb, false);
            imagesavealpha($thumb, true);
            $source = imagecreatefrompng($file);
            break;
        case 'image/gif':
            $background = imagecolorallocate($thumb, 0, 0, 0);
            imagecolortransparent($thumb, $background);
            imagealphablending($thumb, false);
            imagesavealpha($thumb, true);
            $source = imagecreatefromgif($file);
            break;
        case 'image/jpeg': 
        case 'image/jpg':
            $source = imagecreatefromjpeg($file);
            break;
    }

    imagecopyresized($thumb, $source, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);

    switch($imageType){
        case 'image/png': 
            $image = imagepng($thumb, $file, 0);
            break;
        case 'image/gif':
            $image = imagegif($file);
            break;
        case 'image/jpeg': 
        case 'image/jpg':
            $image = imagejpeg($thumb, $file, 100);
            break;
    }

    return $image;
}

输出：

File is an image - image/jpeg.resized 17 times

免责声明：一切正常，您的图像质量会受到影响。需要努力。