更改图像大小 - PHP
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Change Image Size - PHP
提问by ZyteX
I have recently created an upload function, but I don't know how to change the width and height to 75px... I tried one code I found through Google, but I just got this error:
我最近创建了一个上传功能，但我不知道如何将宽度和高度更改为 75px...我尝试了通过 Google 找到的一个代码，但我刚刚收到此错误：
( ! ) Fatal error: Class 'Imagick' not found in C:\wamp\www\Legendary\new\usersettings.php on line 725
Call Stack
# Time Memory Function Location
1 0.0042 880616 {main}( ) ..\usersettings.php:0
Here's my current code (including the code which didn't work):
这是我当前的代码（包括不起作用的代码）：
echo '
<table border="0" width="100%">
<tr><td style="font-size: 16px;">Change Image</td></tr>
<form action="" method="post" enctype="multipart/form-data">
<tr><td>Upload Image:</td><td style="text-align: right;"><input type="file" name="upimage" id="upimage" /></td></tr>
<tr><td></td><td style="text-align: right; font-size: 10px;"></td></tr>
<tr><td></td><td style="text-align: right;"><input type="submit" name="submitnewimage" value="Upload" class="button" /></td></tr>
</form>
';
echo '
</table>
';
if(isset($_POST['submitnewimage'])){
$name = $_FILES['upimage']['name'];
$temp = $_FILES['upimage']['tmp_name'];
$type = $_FILES['upimage']['type'];
$size = $_FILES['upimage']['size'];
if($name!=""){
include 'config.php';
$sql5 = mysql_query("SELECT * FROM images ORDER BY id DESC LIMIT 1");
while($row=mysql_fetch_array($sql5)) {
if(!isset($show2)){
$id = $row['id'];
$id = $id + 1;
$show2 = "YES";
}
}
if(($type=="image/jpeg") || ($type=="image/jpg") || ($type=="image/gif") || ($type=="image/pjpeg") || ($type=="image/png")){
if($size<=100000){
$pos = strrpos($name, '.');
if($pos === false)
$ext = "";
$ext = substr($name, $pos);
$newFilename = $id.$ext;
move_uploaded_file($temp, "images/teamicons/".$newFilename);
$im = new Imagick('images/teamicons/'.$newFilename);
$im->thumbnailImage(75,75);
$im->writeImage('images/teamicons/'.$newFilename);
mysql_query("INSERT INTO `images`(`id`, `name`, `size`, `type`) VALUES (NULL,'$newFilename',$size,'$type')");
$myusername = $_SESSION['myusername'];
mysql_query("UPDATE `members` SET `img`= '$newFilename' WHERE `username`='$myusername'");
header("Location:" . $_SESSION['prev_page']);
}else{echo "<tr><td colspan='2'><span style='color:#F00;'>The file, "".$name."", is too large! Maximum allowed file size is 100kB.</span></td></tr>";}
}else{echo "<tr><td colspan='2'><span style='color:#F00;'>"".$type."" is not a valid file type!</span></td></tr>";}
}else{echo "<tr><td colspan='2'><span style='color:#F00;'>No file has been specified!</span></td></tr>";}
}
Is there any way of changing the width and height of the images?
有没有办法改变图像的宽度和高度？
回答by Max Spencer
I've successfully used GDto do this recently, specifically using the imagecopyresampledfunction.
我最近成功地使用GD来做到这一点，特别是使用该imagecopyresampled功能。
To expand a little on that... Once I had the image uploaded (which I wont go into, because that is a whole other issue), I did something fairly simple like this:
稍微扩展一下......一旦我上传了图像（我不会进入，因为这是另一个问题），我做了一些非常简单的事情：
$original_info = getimagesize($filename);
$original_w = $original_info[0];
$original_h = $original_info[1];
$original_img = imagecreatefromjpg($filename);
$thumb_w = 100;
$thumb_h = 100;
$thumb_img = imagecreatetruecolor($thumb_w, $thumb_h);
imagecopyresampled($thumb_img, $original_img,
0, 0,
0, 0,
$thumb_w, $thumb_h,
$original_w, $original_h);
imagejpeg($thumb_img, $thumb_filename);
imagedestroy($thumb_img);
imagedestroy($original_img);
Please note that I have not tested this code. It's just here to give you a basic idea of my method.
请注意，我尚未测试此代码。在这里只是为了让您对我的方法有一个基本的了解。
回答by dimitril
The Imagick Class is not found, because it is a PHP extension you need to install on your server.
找不到 Imagick 类，因为它是您需要在服务器上安装的 PHP 扩展。
Read the following documentation to find instructions on how to use/install the extension. http://www.php.net/manual/en/book.imagick.php
阅读以下文档以查找有关如何使用/安装扩展的说明。 http://www.php.net/manual/en/book.imagick.php
回答by TMS
I use code like this:
我使用这样的代码：
$t = imagecreatefromjpeg($old_path);
$x = imagesx($t);
$y = imagesy($t);
$s = imagecreatetruecolor($new_width, $new_height);
imagecopyresampled($s, $t, 0, 0, 0, 0, $new_width, $new_height,
$x, $y);
imagejpeg($s, $new_path);
chmod($new_path, 0644);
回答by TMS
You can also scale the image client-side, e.g. using plupload library(can resize JPEG and PNG).
您还可以在客户端缩放图像，例如使用plupload 库（可以调整 JPEG 和 PNG 的大小）。
回答by Vasilii Suricov
Simple solutions some times changed alfa (transparent png). For me forks only this (it's real, just copy-pasted code)
简单的解决方案有时会改变 alfa（透明 png）。对我来说只有这个（它是真实的，只是复制粘贴的代码）
public static function resize($filename, $maxW, $maxH, $ext = null)
{
if ($ext === null)
$ext = strtolower(pathinfo($filename, PATHINFO_EXTENSION));
else
$ext = strtolower($ext);
list($origW, $origH) = getimagesize($filename);
$w = $origW;
$h = $origH;
# taller
if ($h > $maxH) {
$w = ($maxH / $h) * $w;
$h = $maxH;
}
# wider
if ($w > $maxW) {
$h = ($maxW / $w) * $h;
$w = $maxW;
}
$resource = imagecreatetruecolor($w, $h);
# MUST IMPORTANT TWO ROWS
imagesavealpha($resource, true);
imagefill($resource, 0, 0, 0x7fffffff);
if ($ext == 'jpeg' || $ext == 'jpg') {
$image = imagecreatefromjpeg($filename);
} else if ($ext == 'png') {
$image = imagecreatefrompng($filename);
} else {
throw new Exception('Unsupported extension');
}
imagecopyresampled(
$resource,
$image, 0, 0, 0, 0,
$w, $h, $origW, $origH
);
imagedestroy($image);
return $resource;
}
