用于png / jpeg的php中的平均图像颜色

Question

I want to calculate the average color of an image (png or jpg) in php.

I want a little script that will go fast to calculate the average color.

I tried by resizing an image to 1px by 1px but I didn't have success. I always have an error like this : imagesx() expects parameter 1 to be resource, string given in

Here is my php:

$post_thumb   = wp_get_attachment_url( get_post_thumbnail_id() );   
$img = $post_thumb;
$x = imagesx($img);
$y = imagesy($img);
$tmp_img = ImageCreateTrueColor(1,1);
ImageCopyResampled($tmp_img,$img,0,0,0,0,1,1,$x,$y);
$rgb = ImageColorAt($tmp_img,0,0);

I know it comes from my image var but I don't know how to resolve it...

Answer 1

I'v got it, it was a problem from my var object:

$img = @imagecreatefromstring(file_get_contents($post_thumb));
$x = imagesx($img);
$y = imagesy($img);
$tmp_img = ImageCreateTrueColor(1,1);
ImageCopyResampled($tmp_img,$img,0,0,0,0,1,1,$x,$y);
$rgb = ImageColorAt($tmp_img,0,0);
$r   = ($rgb >> 16) & 0xFF;
$g = ($rgb >> 8) & 0xFF;
$b  =  $rgb & 0xFF;