我得到图像作为base64编码字符串前端，我必须解码它们并将它们保存为服务器中的图像。图像可以是任何格式- png,gif或jpeg。这部分工作正常。但有时用户上传的图像可能非常大，所以我试图从后端压缩它们，这部分失败了。
我有两个函数。一个用于将base64字符串转换为图像，另一个用于压缩它。
将字符串转换为图像的函数。
function uploadTimelineImage($base64Img)
{
$data= array();
$upAt=date('YmdHis');
if (strpos($base64Img, 'data:image/png;base64') !== false)
{
$img = str_replace('data:image/png;base64,', '', $base64Img);
$img = str_replace(' ', '+', $img);
$data = base64_decode($img);
$extension= 'png';
}
if (strpos($base64Img, 'data:image/gif;base64') !== false)
{
$img = str_replace('data:image/gif;base64,', '', $base64Img);
$img = str_replace(' ', '+', $img);
$data = base64_decode($img);
$extension= 'gif';
}
if (strpos($base64Img, 'data:image/jpeg;base64') !== false)
{
$img = str_replace('data:image/jpeg;base64,', '', $base64Img);
$img = str_replace(' ', '+', $img);
$data = base64_decode($img);
$extension= 'jpeg';
}
$fileName = 'img'.$upAt.$extension;
$filePath = 'foldername/'.'img'.$upAt.$extension;
//upload image to folder
$success = file_put_contents($filePath, $data);
$result = $success ? 1 : 0;
//call to compression function
$compressThisImg= $filePath;
$d = compress($compressThisImg, $fileName, 80);
if($result==1)
{
return $fileName;
}
else
{
return null;
}
}
这是进行压缩的函数:
//Function to compress an image
function compress($source, $destination, $quality)
{
$info = getimagesize($source);
if ($info['mime'] == 'image/jpeg')
$image = imagecreatefromjpeg($source);
elseif ($info['mime'] == 'image/gif')
$image = imagecreatefromgif($source);
elseif ($info['mime'] == 'image/png')
$image = imagecreatefrompng($source);
imagejpeg($image, $destination, $quality);
return $destination;
}
但是上面的函数不做任何压缩，它抛出错误:
failed to open stream: No such file or directory
and my function上传原始图像
为什么你不使用这个函数来创建任何类型的图像形式base64 edncoded图像字符串?
function uploadTimelineImage($base64Img,$h,$w)
{
$im = imagecreatefromstring($base64Img);
if ($im !== false) {
$width = imagesx($im);
$height = imagesy($im);
$r = $width / $height; // ratio of image
// calculating new size for maintain ratio of image
if ($w/$h > $r) {
$newwidth = $h*$r;
$newheight = $h;
} else {
$newheight = $w/$r;
$newwidth = $w;
}
$dst = imagecreatetruecolor($newwidth, $newheight);
imagecopyresampled($dst, $im, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);
imagedestroy($im);
$fileName = 'img'.date('Ymd').'.jpeg';
$filepath = 'folder/'.$fileName ;
imagejpeg($dst,$filepath);
imagedestroy($dst);
return $fileName;
}
else
{
return "";
}
}