php proportionally resize and cut a circle out of a square image

问题

I have many square images with different sizes, and I want to first resize them so they are inside a 150pixel area (so the images are not distorted, so since most images are not exactly the same size on both height and width one of the sides would be smaller (proportionally).

Then once I do that I need to cut a perfect circle out of them and apply a 10pixel colored border.

Now how on earth could I even start this?

回答1:

Well, you take your files from disk or however and then you use them to create a new image, like so:

//Would want to use imagecreatefromgif or imagecreatefrompng, depending on file type.
//Loading up the image so we can get it's dimensions and determine the proper size.
$maxsize = 150;
$img = imagecreatefromjpeg("$jpgimage"); 


$width = imagesx($img);
$height = imagesy($img); //Get height and width

//This stuff figures out the ratio to reduce the shortest side by by using the longest side, since 
//the longest side will be the new maximum length
if ($height > $width) 
{   
$ratio = $maxsize / $height;  
$newheight = $maxsize;
$newwidth = $width * $ratio; 
{
else 
{
$ratio = $maxsize / $width;   
$newwidth = $maxsize;  
$newheight = $height * $ratio;   
}

//create new image resource to hold the resized image
$newimg = imagecreatetruecolor($newwidth,$newheight); 

$palsize = ImageColorsTotal($img);  //Get palette size for original image
for ($i = 0; $i < $palsize; $i++) //Assign color palette to new image
{ 
$colors = ImageColorsForIndex($img, $i);   
ImageColorAllocate($newimg, $colors['red'], $colors['green'], $colors['blue']);
} 

//copy original image into new image at new size.
imagecopyresized($newimg, $img, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);

//Get a color for the circle, in this case white.
$circlecol = imagecolorallocate($newimg,255,255,255);
//draw circle at center point, or as close to center as possible, with a width and height of 150
//use imagefilledellipse for a filled circle
imageellipse($newimg, round($newwidth / 2), round($newheight / 2), 150, 150, $circlecol);

Does the circle need to be bordered or the image as a whole?

来源：https://stackoverflow.com/questions/4512477/php-proportionally-resize-and-cut-a-circle-out-of-a-square-image