按大小压缩图像

Question

Is it possible to compress an image by its size using PHP? I mean I let the user enter the size of the image in KB and they get the image in that size.

Answer 1

You could compress the image of sorts by recreating the image with new dimensions.

$image_name = $_FILES['image']['name'];
$image_name_tmp = $_FILES['image']['tmp_name'];
$ext = pathinfo($image_name, PATHINFO_EXTENSION);

if($ext=='jpg' || $ext=='jpeg' || $ext=='JPG' || $ext=='JPEG')
{
    $src = imagecreatefromjpeg($image_name_tmp);
}
else if($ext=="png" || $ext=="PNG")
{
$src = imagecreatefrompng($image_name_tmp);
}
else 
{
$src = imagecreatefromgif($image_name_tmp);
}


list($width, $height) = getimagesize($image_name_tmp);

$n_width = 320;
$n_height = ($height / $width) * $n_width;

$temp_image = imagecreatetruecolor($n_width, $n_height);
imagecopyresampled($temp_image, $src, 0, 0, 0, 0, $n_width, $n_height, $width, $height);
imagejpeg($temp_image, $target, 100);