我正在从一个 URL 调整和保存多个图像的大小并想知道如何压缩这些图像，因为保存在 640x320 文件夹中的图像是 400kb，这太大了，我想知道如何压缩这些图像更多，谢谢提前寻求任何建议！
PHP 调整大小和大小处理程序
include("../includes/picture-resize.php");
$image = $_POST['thumbnail'];
$slug = $_POST['slug'];
$images = $_POST['screenshots'];
$list = explode(",", $images);
$listlength = count($list);
$i = 0;
$image = $_POST['thumbnail'];
$path = parse_url($image, PHP_URL_PATH);
$filename = $slug.'-'.$i;
$extension = pathinfo($path, PATHINFO_EXTENSION);
$file = $filename.'.'.$extension;
file_put_contents('../tmp/' . $file, file_get_contents($image));
$picture = new pic_resize();
$picture->load('../tmp/'.$file);
$picture->resizeToWidth(125);
mkdir('../images/125x125/'.$slug);
$picture->save('../images/125x125/'.$slug.'/'.$file, $picture->image_type);
unlink('../tmp/'.$file);
$thumbnail = $file;
$new_list = array();
mkdir('../images/640x320/'.$slug);
mkdir('../images/310x205/'.$slug);
while($listlength > $i) {
$path = parse_url($list[$i], PHP_URL_PATH);
$filename = $slug.'-'.$i;
$extension = pathinfo($path, PATHINFO_EXTENSION);
$file = $filename.'.'.$extension;
file_put_contents('../tmp/' . $file, file_get_contents($list[$i]));
$picture = new pic_resize();
$picture->load('../tmp/'.$file);
$picture->resizeToWidth(640);
$picture->save('../images/640x320/'.$slug.'/'.$file, $picture->image_type);
$picture->resizeToWidth(310);
$picture->save('../images/310x205/'.$slug.'/'.$file, $picture->image_type);
unlink('../tmp/'.$file);
array_push($new_list, $file);
$i++;
}
PHP 调整大小类
class pic_resize{
var $image;
var $image_type;
function load($filename) {
$image_info = getimagesize($filename);
$this->image_type = $image_info[2];
if( $this->image_type == IMAGETYPE_JPEG ) {
$this->image = imagecreatefromjpeg($filename);
} elseif( $this->image_type == IMAGETYPE_GIF ) {
$this->image = imagecreatefromgif($filename);
} elseif( $this->image_type == IMAGETYPE_PNG ) {
$this->image = imagecreatefrompng($filename);
}
}
function save($filename, $image_type, $compression=75, $permissions=null) {
if( $image_type == IMAGETYPE_JPEG ) {
imagejpeg($this->image,$filename,$compression);
} elseif( $image_type == IMAGETYPE_GIF ) {
imagegif($this->image,$filename);
} elseif( $image_type == IMAGETYPE_PNG ) {
imagepng($this->image,$filename,9,PNG_FILTER_PAETH);
}
if( $permissions != null) {
chmod($filename,$permissions);
}
}
function output($image_type=IMAGETYPE_JPEG) {
if( $image_type == IMAGETYPE_JPEG ) {
imagejpeg($this->image);
} elseif( $image_type == IMAGETYPE_GIF ) {
imagegif($this->image);
} elseif( $image_type == IMAGETYPE_PNG ) {
imagepng($this->image);
imagealphablending($this->image, false);
imagesavealpha($this->image, true);
}
}
function getWidth() {
return imagesx($this->image);
}
function getHeight() {
return imagesy($this->image);
}
function resizeToHeight($height) {
$ratio = $height / $this->getHeight();
$width = $this->getWidth() * $ratio;
$this->resize($width,$height);
}
function resizeToWidth($width) {
$ratio = $width / $this->getWidth();
$height = $this->getheight() * $ratio;
$this->resize($width,$height);
}
function scale($scale) {
$width = $this->getWidth() * $scale/100;
$height = $this->getheight() * $scale/100;
$this->resize($width,$height);
}
function resize($width,$height) {
$new_image = imagecreatetruecolor($width, $height);
imagealphablending($new_image, false);
imagesavealpha($new_image, true);
imagecopyresampled($new_image, $this->image, 0, 0, 0, 0, $width, $height, $this->getWidth(), $this->getHeight());
$this->image = $new_image;
}
}