PHP 调整图像大小

Question

可能的重复：
有人可以建议 php 中最好的图像调整大小脚本吗？< /a>

对于 PHP 中的图像处理或文件处理，我仍然是新手。

希望您能提供有关以下内容的任何意见，

我使用简单的 html 表单发布图像文件并通过 php 上传。 当我尝试更改代码以适应更大的文件（即调整大小）时，我收到错误。 一直在网上搜索，但找不到任何真正简单的东西。

$size = getimagesize($_FILES['image']['tmp_name']);

//compare the size with the maxim size we defined and print error if bigger
if ($size == FALSE)
{
    $errors=1;
}else if($size[0] > 300){   //if width greater than 300px
    $aspectRatio = 300 / $size[0];
    $newWidth = round($aspectRatio * $size[0]);
    $newHeight = round($aspectRatio * $size[1]);
    $imgHolder = imagecreatetruecolor($newWidth,$newHeight);
}

$newname= ROOTPATH.LOCALDIR."/images/".$image_name; //image_name is generated

$copy = imagecopyresized($imgHolder, $_FILES['image']['tmp_name'], 0, 0, 0, 0, $newWidth, $newHeight, $size[0], $size[1]);
move_uploaded_file($copy, $newname); //where I want to move the file to the location of $newname

我得到的错误是：

imagecopyresized()：提供的参数 不是有效的图像资源

感谢

---

感谢您的所有输入，我已将其更改为此

$oldImage = imagecreatefromstring(file_get_contents($_FILES['image']['tmp_name']));
$copy = imagecopyresized($imgHolder, $oldImage, 0, 0, 0, 0, $newWidth, $newHeight, $size[0], $size[1]);
if(!move_uploaded_file($copy, $newname)){
    $errors=1;
}

未收到 PHP 日志错误但未保存:(

有什么想法吗？

再次感谢

---

结果

以下作品 。

$oldImage = imagecreatefromjpeg($img);
$imageHolder = imagecreatetruecolor($newWidth, $newHeight);
imagecopyresized($imageHolder, $oldImage, 0, 0, 0, 0, $newWidth, $newHeight, $width, $height);
imagejpeg($imageHolder, $newname, 100);

谢谢大家的帮助

Answer 1

imagecopyresized 将图像资源作为其第二个参数，而不是文件名。您需要先加载该文件。如果您知道文件类型，则可以使用imagecreatefromFILETYPE来加载它。例如，如果它是 JPEG，请使用 imagecreatefromjpeg 并传递文件名 - 这将返回图像资源。

如果您不知道文件类型，也不会丢失一切。您可以将文件作为字符串读取，并使用 imagecreatefromstring（自动检测文件类型）加载它，如下所示：

$oldImage = imagecreatefromstring(file_get_contents($_FILES['image']['tmp_name']));

Answer 2

$_FILES['image']['tmp_name'] 是路径而不是图像资源。您必须使用 imagecreatefrom*() 函数之一来创建资源。

Answer 3

这是我保存缩略图的实现：

调整大小并保存功能：

function SaveThumbnail($imagePath, $saveAs, $max_x, $max_y) 
{
    ini_set("memory_limit","32M");
    $im  = imagecreatefromjpeg ($imagePath);
    $x = imagesx($im);
    $y = imagesy($im);

    if (($max_x/$max_y) < ($x/$y)) 
    {
        $save = imagecreatetruecolor($x/($x/$max_x), $y/($x/$max_x));
    }
    else 
    {
        $save = imagecreatetruecolor($x/($y/$max_y), $y/($y/$max_y));
    }
    imagecopyresized($save, $im, 0, 0, 0, 0, imagesx($save), imagesy($save), $x, $y);

    imagejpeg($save, $saveAs);
    imagedestroy($im);
    imagedestroy($save);
}

用法：

$thumb_dir = "/path/to/thumbnaildir/"
$thumb_name = "thumb.jpg"
$muf = move_uploaded_file($_FILES['imgfile']['tmp_name'], "/tmp/test.jpg")

if($muf)
{
    SaveThumbnail("/tmp/test.jpg", $thumb_dir . $thumb_name, 128, 128);
}

Answer 4

我使用 ImageMagick 来处理类似的事情。看看它是多么简单！

我的脚本之一的示例：

$target= //destination path
move_uploaded_file($_FILES['item']['tmp_name'],$target);

$image = new imagick($target);

$image->setImageColorspace(imagick::COLORSPACE_RGB);
$image->scaleImage(350,0);

$image->writeImage($target);

然后您可以使用 getImageGeometry()< /a> 获取宽度和高度。

例如：

$size=$image->getImageGeometry();
if($size['width'] > 300){   //if width greater than 
   $image->scaleImage(300,0);
}

另外，使用scaleImage(300,0)意味着ImageMagick会根据宽高比自动计算高度。

Answer 5

我正在做类似的事情。我尝试过 Ghostscript 和 ImageMagic。它们是很好的工具，但需要一些时间来设置。我最终在 Snow Leopard 服务器上使用了“sips”。不确定它是否内置于 Linux 服务器中，但如果您需要快速完成某件事，这是我发现的更快的解决方案。

Answer 6

function resizeImage($file){

         define ('MAX_WIDTH', 1500);//max image width               
         define ('MAX_HEIGHT', 1500);//max image height 
         define ('MAX_FILE_SIZE', 10485760);

         //iamge save path
         $path = 'storeResize/';  

        //size of the resize image 
         $new_width = 128; 
         $new_height = 128;    

        //name of the new image           
        $nameOfFile = 'resize_'.$new_width.'x'.$new_height.'_'.basename($file['name']);       

        $image_type = $file['type'];
        $image_size = $file['size'];
        $image_error = $file['error'];
        $image_file = $file['tmp_name'];
        $image_name = $file['name'];        

        $image_info = getimagesize($image_file);

        //check image type 
        if ($image_info['mime'] == 'image/jpeg' or $image_info['mime'] == 'image/jpg'){    
        }
        else if ($image_info['mime'] == 'image/png'){    
        }
        else if ($image_info['mime'] == 'image/gif'){    
        }
        else{            
            //set error invalid file type
        }

        if ($image_error){
            //set error image upload error
        }

        if ( $image_size > MAX_FILE_SIZE ){
            //set error image size invalid
        }

        switch ($image_info['mime']) {
            case 'image/jpg': //This isn't a valid mime type so we should probably remove it
            case 'image/jpeg':
            $image = imagecreatefromjpeg ($image_file);
            break;
            case 'image/png':
            $image = imagecreatefrompng ($image_file);
            break;
            case 'image/gif':
            $image = imagecreatefromgif ($image_file);
            break;
        }    

        if ($new_width == 0 && $new_height == 0) {
            $new_width = 100;
            $new_height = 100;
        }

        // ensure size limits can not be abused
        $new_width = min ($new_width, MAX_WIDTH);
        $new_height = min ($new_height, MAX_HEIGHT);

        //get original image h/w
        $width = imagesx ($image);
        $height = imagesy ($image);

        //$align = 'b';
        $zoom_crop = 1;
        $origin_x = 0;
        $origin_y = 0;
        //TODO setting Memory

        // generate new w/h if not provided
        if ($new_width && !$new_height) {
            $new_height = floor ($height * ($new_width / $width));
        } else if ($new_height && !$new_width) {
            $new_width = floor ($width * ($new_height / $height));
        }

        // scale down and add borders
    if ($zoom_crop == 3) {

         $final_height = $height * ($new_width / $width);

         if ($final_height > $new_height) {
            $new_width = $width * ($new_height / $height);
         } else {
            $new_height = $final_height;
         }

    }

        // create a new true color image
        $canvas = imagecreatetruecolor ($new_width, $new_height);
        imagealphablending ($canvas, false);


        if (strlen ($canvas_color) < 6) {
            $canvas_color = 'ffffff';       
        }

        $canvas_color_R = hexdec (substr ($canvas_color, 0, 2));
        $canvas_color_G = hexdec (substr ($canvas_color, 2, 2));
        $canvas_color_B = hexdec (substr ($canvas_color, 2, 2));

        // Create a new transparent color for image
        $color = imagecolorallocatealpha ($canvas, $canvas_color_R, $canvas_color_G, $canvas_color_B, 127);

        // Completely fill the background of the new image with allocated color.
        imagefill ($canvas, 0, 0, $color);

        // scale down and add borders
    if ($zoom_crop == 2) {

            $final_height = $height * ($new_width / $width);

        if ($final_height > $new_height) {
            $origin_x = $new_width / 2;
            $new_width = $width * ($new_height / $height);
            $origin_x = round ($origin_x - ($new_width / 2));
            } else {

            $origin_y = $new_height / 2;
            $new_height = $final_height;
            $origin_y = round ($origin_y - ($new_height / 2));

        }

    }

        // Restore transparency blending
        imagesavealpha ($canvas, true);

        if ($zoom_crop > 0) {

            $src_x = $src_y = 0;
            $src_w = $width;
            $src_h = $height;

            $cmp_x = $width / $new_width;
            $cmp_y = $height / $new_height;

            // calculate x or y coordinate and width or height of source
            if ($cmp_x > $cmp_y) {
        $src_w = round ($width / $cmp_x * $cmp_y);
        $src_x = round (($width - ($width / $cmp_x * $cmp_y)) / 2);
            } else if ($cmp_y > $cmp_x) {
        $src_h = round ($height / $cmp_y * $cmp_x);
        $src_y = round (($height - ($height / $cmp_y * $cmp_x)) / 2);
            }

            // positional cropping!
        if ($align) {
            if (strpos ($align, 't') !== false) {
                $src_y = 0;
            }
                        if (strpos ($align, 'b') !== false) {
                                $src_y = $height - $src_h;
                        }
                        if (strpos ($align, 'l') !== false) {
                $src_x = 0;
            }
            if (strpos ($align, 'r') !== false) {
                $src_x = $width - $src_w;
            }
        }

            // positional cropping!
            imagecopyresampled ($canvas, $image, $origin_x, $origin_y, $src_x, $src_y, $new_width, $new_height, $src_w, $src_h);

         } else {       
        imagecopyresampled ($canvas, $image, 0, 0, 0, 0, $new_width, $new_height, $width, $height);
    }
        //Straight from Wordpress core code. Reduces filesize by up to 70% for PNG's
        if ( (IMAGETYPE_PNG == $image_info[2] || IMAGETYPE_GIF == $image_info[2]) && function_exists('imageistruecolor') && !imageistruecolor( $image ) && imagecolortransparent( $image ) > 0 ){
            imagetruecolortopalette( $canvas, false, imagecolorstotal( $image ) );
    }
        $quality = 100;            
        $nameOfFile = 'resize_'.$new_width.'x'.$new_height.'_'.basename($file['name']);       

    if (preg_match('/^image\/(?:jpg|jpeg)$/i', $image_info['mime'])){                       
        imagejpeg($canvas, $path.$nameOfFile, $quality);  

    } else if (preg_match('/^image\/png$/i', $image_info['mime'])){                         
        imagepng($canvas, $path.$nameOfFile, floor($quality * 0.09)); 

    } else if (preg_match('/^image\/gif$/i', $image_info['mime'])){               
        imagegif($canvas, $path.$nameOfFile); 

    }
}