Question

我在我的网站中使用plupload课程，我上传了工作。但是，当我上传单个文件时，我想为该文件创建多个分辨率。我尝试使用下面的javascript：尝试做这个客户端然后上传图像使事情更快。不过，我打开了调整服务器上传图像的大小。

我的尝试：

 $(function() {
    $('#html5_uploader_" . $a1 . "').pluploadQueue({
        // General settings
        runtimes : 'html5',
        url : 'http://domain.com.au/fileuploader',

        filters : {
            max_file_size : '1024mb',
            mime_types: [
                {title : 'Image files', extensions : 'jpg,gif,png'}
            ]
        },

        // Resize images on clientside if we can
        resize : {width : 800, height : 600, quality : 90}
    });
});

Answer 1

这里有一小组函数，可以让你在php中轻松处理和生成缩略图。如果图像是一个矩形，则将其中心切割并相应裁剪。

功能签名

function square_thumbs(string $input_name,array $data_source, array $sizes,int $min_width,$int $min_height)

返回值

返回生成的缩略图的文件名数组订购$ sizes数组

示例用法

list($small,$medium,$large) = square_thumbs('image_file',$_FILES,[60,150,300],120,120);

完整代码

function square_thumbs($img_name,$files,$sizes = [60,220,800],$min_width=120,$min_height=120)
{
    if(empty($files) || !isset($files[$img_name])){
        throw new \exception('You must select an image!');
    }
    if($files[$img_name]['error'])
    {
        throw new exception(upload_errors($files[$img_name]['error']));
    }
    $image_temp = $files[$img_name]['tmp_name'];
    @$image_info = getimagesize($image_temp);
    $exif = [IMAGETYPE_GIF,IMAGETYPE_JPEG,IMAGETYPE_PNG];
    $finfo  = ['image/gif','image/png','image/jpeg','image/pjpeg'];
    $etype = exif_imagetype($image_temp);
    if(!function_exists('finfo_file')){
        throw new exception('Unable to determine image mime type.');
    }
    $type = finfo_file(finfo_open(FILEINFO_MIME_TYPE),$image_temp);
    if( !is_uploaded_file($files[$img_name]['tmp_name']) ){
        throw new exception('bad file input');
    }
    if( !in_array($etype,$exif) || !in_array($type,$finfo)){
        throw new exception('file type not allowed');
    }
    switch($type){
        case 'image/gif':
            $type2 = 'gif';
        break;
        case 'image/png':
            $type2 = 'png';
        break;
        case 'image/jpeg':
        case 'image/jpg':
        case 'image/pjpeg':
            $type2 = 'jpg';
        break;
    }
    if( !$image_info ){
        throw new exception('invalid image size.');
    }

    //get the image resource
    $image = imagecreatefromstring(file_get_contents($image_temp));
    $width  = $image_info[0];
    $height = $image_info[1];


    if($width < $min_width || $height < $min_height){
        throw new exception('Images must be atleast '.$min_width.' x '.$min_height.' in size.');
    }

    //ill admit this code is smelly, but do you have a better idea? lol
    if($width != $height){
        list($size,$image) = square_img($image,$width,$height);
        $width = $height = $size;
    }
    $size = $width;

    //now we have a square image and our image size is updated to reflect this change.
    $res = [];
    foreach($sizes as $z)
    {
        $t = imagecreatetruecolor($z,$z);
        ob_start();
        switch($type){
            case 'image/gif':
                imagecopyresampled($t,$image,0,0,0,0,$z,$z,$size,$size);
                imagegif($t);
            break;
            case 'image/png':
                imagesavealpha($t, true);
                $trans_colour = imagecolorallocatealpha($t, 0, 0, 0, 127);
                imagefill($t, 0, 0, $trans_colour);
                imagecopyresampled($t,$image,0,0,0,0,$z,$z,$size,$size);
                imagepng($t,NULL,2); //lossless compression minimal (default is 6)
            break;
            case 'image/jpeg':
            case 'image/jpg':
            case 'image/pjpeg':
                imagecopyresampled($t,$image,0,0,0,0,$z,$z,$size,$size);
                imagejpeg($t,NULL,100); //100% quality (default is 75%)
            break;
        }
        $result_image = ob_get_clean(); //stores the image content as string.
        $file_name = md5($result_image).'.'.$type2; //we can create a random distinct file name by md5ing the data and appending the file extension which is stored in $type2 variable.
        $res[] = store_image($result_image,$file_name); //store name of the resultant file in result array
    }
    return $res; //after all the thumbs have been generated, return them all in an array.
}

//calculates the nearest square size of the image
function square_img($image,$width,$height)
{
    //horizontal rectangle
    if ($width > $height) {
        $square = $height;              // $square: square side length
        $offsetX = ($width - $height) / 2;  // x offset based on the rectangle
        $offsetY = 0;              // y offset based on the rectangle
    }
    // vertical rectangle
    elseif ($height > $width) {
        $square = $width;
        $offsetX = 0;
        $offsetY = ($height - $width) / 2;
    }
    $t = imagecreatetruecolor($square,$square);
    imagecopyresampled($t, $image, 0, 0, $offsetX, $offsetY, $square, $square, $square, $square);
    return [$square,$t];
}


//handle some common upload errors 
function upload_errors($err_code) {
    switch ($err_code) {
        case UPLOAD_ERR_INI_SIZE:
            return 'The uploaded file exceeds the upload_max_filesize directive in php.ini';
        case UPLOAD_ERR_FORM_SIZE:
            return 'The uploaded file exceeds the MAX_FILE_SIZE directive that was specified in the HTML form';
        case UPLOAD_ERR_PARTIAL:
            return 'The uploaded file was only partially uploaded';
        case UPLOAD_ERR_NO_FILE:
            return 'No file was uploaded';
        case UPLOAD_ERR_NO_TMP_DIR:
            return 'Missing a temporary folder';
        case UPLOAD_ERR_CANT_WRITE:
            return 'Failed to write file to disk';
        case UPLOAD_ERR_EXTENSION:
            return 'File upload stopped by extension';
        default:
            return 'Unknown upload error';
    }
}


//stores the resultant image.
function store_image($image_data,$file_name,$path='')
{
    //this is just a basic implementation of storing some data into a file.
    $t = fopen($path.$file_name,'w+');
    fwrite($t,$image_data);
    fclose($t);
    return $file_name;
}

plupload多个调整大小的客户端大小

1 个答案: