PHP将jpg图像分成两个相等的图像并保存

Question

I have a jpg picture which I want to split into two equal images. The split should happen in the horizontal center of the image and save both parts (left part, right part). For instance an image of 500x300 would be split into two images each 250x300. I am not familiar with the right image processing function, and when checking PHP's docs it clearly warns that 'imagecrop()' is not documented (http://php.net/manual/en/function.imagecrop.php). Also on stackoverflow, the only thing which I found is this snippet which I tried to play around with:

// copy left third to output image
imagecopy($output, $orig,$padding,$padding,0, 0,$width/3,$height);
// copy central third to output image
imagecopy($output, $orig,2*$padding+$width/3,$padding,$width/3, 0,$width/3,$height);

Maybe you could point me to the right direction.

Thanks a lot

Answer 1

Function imagecopy() is well documented & can do exactly what you want. For example:

imagecopy($leftSide, $orig, 0, 0, 0, 0, $width/2, $height);
imagecopy($rightSide, $orig, 0, 0, $width/2, 0, $width/2, $height);

Ofcourse first you need to write your image in variable $orig with functions like: imagecreatefrompng, imagecreatefromgif, etc. EG:

$orig= imagecreatefromjpeg('php.jpg');

Then you need to create new empty image variables for both image sides: with imagecreatetruecolor, eg:

$leftSide = imagecreatetruecolor($width/2, $height);
$rightSide = imagecreatetruecolor($width/2, $height);

And then just save those two variables to new files using functions by needed extension, like imagejpeg. EG:

imagejpeg($leftSide, 'leftSide.jpg');
imagejpeg($rightSide, 'rightSide.jpg');