我正在开发一个网站，用户可以将多个图像上传到服务器/网站，在我的上传脚本中，我将图像大小限制为10MB。这是因为我认为很多现代相机都能拍摄大图像。
上传脚本每次获取一张图像，并将大小调整为3个不同的版本，900x600、600x450和一个较小的缩略图，还将水印图像放在2个较大图像的顶部。
我将php.ini的memory_limit设置为96MB，我认为这已经足够容易了。
经过一点测试，我上传了一张尺寸为6.38MB的jpg图像，分辨率为6143 x 3855 px。我收到错误消息"致命错误：100663296字节的允许内存大小已用完（试图分配24572字节）"
你认为需要这么多内存来上传和处理这样大小的图像合理吗？还是你认为这更可能是我的脚本中的编码问题？
96 MB的内存限制对我来说似乎太多了。其他人在处理大图像上传时有什么经验？我应该将内存限制设置为128MB或更高吗？还是应该考虑重写上传脚本？
我的代码添加在下面：
//If a new image has been added, resize and upload to filesystem
if ($_FILES['new_image']['name'] !=''){
$allowed_types=array(
'image/gif' => '.gif',
'image/jpeg' => '.jpg',
'image/png' => '.png',
'image/x-png' => '.png',
'image/pjpeg' => '.jpg'
);
$img = $_FILES['new_image'];
// Check the file to be uploaded is the correct file type and is under 9MB
if ((array_key_exists($img['type'], $allowed_types)) && ($img['size'] < 9000000)) {
// File to be uploaded is Valid
// File to be uploaded is Valid
$imagename = stripslashes($_FILES['new_image']['name']);
// make the random file name
$randName = md5(rand() * time());
$ext = pathinfo($imagename, PATHINFO_EXTENSION);
$imagename = $randName . "." . $ext;
$source = $_FILES['new_image']['tmp_name'];
// Check if Directory Exists, if not create it
if(!file_exists("images/breeds/".$trimmed['profile_id']))
{
mkdir("images/breeds/".$trimmed['profile_id']) or die("Could not create images folder for article ".$trimmed['profile_id']);
}
// Check if thumbnail Directory Exists
if(!file_exists("images/breeds/".$trimmed['profile_id']."/thumbs"))
{
mkdir("images/breeds/".$trimmed['profile_id']."/thumbs") or die("Could not create thumbnail folder for article ".$trimmed['profile_id']);
}
// Check if thumbnail Directory Exists
if(!file_exists("images/breeds/".$trimmed['profile_id']."/large"))
{
mkdir("images/breeds/".$trimmed['profile_id']."/large") or die("Could not create thumbnail folder for article ".$trimmed['profile_id']);
}
$LargeImage = "images/breeds/".$trimmed['profile_id']."/large/".$imagename;
$NormalImage = "images/breeds/".$trimmed['profile_id']."/".$imagename;
$SmallImage = "images/breeds/".$trimmed['profile_id']."/thumbs/".$imagename;
//uploaded temp file
$file = $_FILES['new_image']['tmp_name'];
//Get Image size info
list($width, $height, $image_type) = getimagesize($file);
//SourceImage
switch ($image_type)
{
case 1: $image = imagecreatefromgif($file); break;
case 2: $image = imagecreatefromjpeg($file); break;
case 3: $image = imagecreatefrompng($file); break;
default: trigger_error('Unsupported filetype!', E_USER_WARNING); break;
}
// Constraints for Large Image
$max_width = 900;
$max_height = 600;
$ratioh = $max_height/$height;
$ratiow = $max_width/$width;
$ratio = min($ratioh, $ratiow);
if (($height < $max_height) && ($width < $max_width)) {
//keep same dimensions
$modwidth = $width;
$modheight = $height;
} else {
// New dimensions
$modwidth = intval($ratio*$width);
$modheight = intval($ratio*$height);
}
$tmpLarge = imagecreatetruecolor( $modwidth, $modheight );
imagecopyresampled($tmpLarge, $image, 0, 0, 0, 0, $modwidth, $modheight, $width, $height) ;
// Add Watermark to large image at top right
$wm = "images/p4h-wm-200.png";
$wmImage = imagecreatefrompng($wm);
$wmW = imagesx($wmImage);
$wmH = imagesy($wmImage);
$photoW = imagesx($tmpLarge);
$photoH = imagesy($tmpLarge);
$dest_x = $photoW - $wmW - 10;
$dest_y = 10;
// imagecopymerge($tn, $wmImage, $dest_x, $dest_y, 0, 0, $wmW, $wmH, 100);
imagecopy($tmpLarge, $wmImage, $dest_x, $dest_y, 0, 0, $wmW, $wmH);
switch ($image_type)
{
case 1: imagegif($tmpLarge,$LargeImage); break;
case 2: imagejpeg($tmpLarge,$LargeImage, 80); break;
case 3: imagepng($tmpLarge,$LargeImage, 0); break;
default: trigger_error('Failed resize image!', E_USER_WARNING); break;
}
// Destroy tmp images to free memory
imagedestroy($tmpLarge);
imagedestroy($wmImage);
// Constraints for Normal Image
$max_width = 550;
$max_height = 413;
$ratioh = $max_height/$height;
$ratiow = $max_width/$width;
$ratio = min($ratioh, $ratiow);
if (($height < $max_height) && ($width < $max_width)) {
//keep same dimensions
$modwidth = $width;
$modheight = $height;
} else {
// New dimensions
$modwidth = intval($ratio*$width);
$modheight = intval($ratio*$height);
}
$tmpNormal = imagecreatetruecolor( $modwidth, $modheight );
imagecopyresampled($tmpNormal, $image, 0, 0, 0, 0, $modwidth, $modheight, $width, $height) ;
// Add Watermark to large image at top right
$wm = "images/p4h-wm-150.png";
$wmImage = imagecreatefrompng($wm);
$wmW = imagesx($wmImage);
$wmH = imagesy($wmImage);
$photoW = imagesx($tmpNormal);
$photoH = imagesy($tmpNormal);
$dest_x = $photoW - $wmW - 10;
$dest_y = 10;
// imagecopymerge($tn, $wmImage, $dest_x, $dest_y, 0, 0, $wmW, $wmH, 100);
imagecopy($tmpNormal, $wmImage, $dest_x, $dest_y, 0, 0, $wmW, $wmH);
switch ($image_type)
{
case 1: imagegif($tmpNormal,$NormalImage); break;
case 2: imagejpeg($tmpNormal,$NormalImage, 90); break;
case 3: imagepng($tmpNormal,$NormalImage, 0); break;
default: trigger_error('Failed resize image!', E_USER_WARNING); break;
}
// Destroy tmp images to free memory
imagedestroy($tmpNormal);
imagedestroy($wmImage);
// Now that the full size image has been saved, resize the thumbnail one to a fixed size for homepage display
// Constraints
$thumb_width = 150;
$thumb_height = 112.5;
// Calculate stuff and resize image accordingly
$src_ratio = $width/$height;
$dst_ratio = $thumb_width/$thumb_height;
if($src_ratio < $dst_ratio) // trim top and bottom
{
$ratio = $width/$thumb_width;
$crop_height = $thumb_height*$ratio;
$src_y = round(($height-$crop_height)/2);
$crop_width = $width;
$src_x = 0;
}
else // trim left and right
{
$ratio = $height/$thumb_height;
$crop_width = $thumb_width*$ratio;
$src_x = round(($width-$crop_width)/2);
$crop_height = $height;
$src_y = 0;
}
$tmpSmall = imagecreatetruecolor( $thumb_width, $thumb_height );
imagecopyresampled($tmpSmall, $image, 0, 0, $src_x, $src_y, $thumb_width, $thumb_height, $crop_width, $crop_height);
switch ($image_type)
{
case 1: imagegif($tmpSmall,$SmallImage); break;
case 2: imagejpeg($tmpSmall,$SmallImage, 90); break;
case 3: imagepng($tmpSmall,$SmallImage, 0); break;
default: trigger_error('Failed resize image!', E_USER_WARNING); break;
}
// Destroy images to free memory
imagedestroy($image);
imagedestroy($tmpSmall);
jpg是6.38MB，但要转换图像，使用的内部表示是原始的未压缩表示。
你的图像是2360万像素
它的未压缩表示可以是每像素32比特（4字节），即：4*23.6MB＝94MB。
所以，我想说，你需要这么大的图像来处理吗？
如果是，则将memory_limit设置为更高如果没有，请将可上传的图像大小限制为更合理的大小，以便在内存设置中进行处理。
您可能需要向PHP提供更多关于何时可以释放内存的提示。一个简单的$some_variable = null;通常就足够了。
完成图像（主图像及其每个缩略图）后，将引用变量设置为null以帮助释放内存。
否则，请尝试打印或记录memory_get_usage()的结果(http://www.php.net/manual/en/function.memory-get-usage.php)在脚本的顶部和整个脚本的各个位置，以跟踪内存陷入困境的地方。
6143x3855图像将需要至少71043795字节的内存用于原始像素数据（每个像素3字节）。然后你创建一系列其他图像来保存原始图像的大小调整版本，等等…
难怪你的记忆力会耗尽。