发生这种情况的最佳方法可能是在内存中创建具有所需组合尺寸的新图像，然后将现有图像复制或重新采样到新图像，然后将新图像保存到磁盘。

例如：

function merge($filename_x, $filename_y, $filename_result) {

 // Get dimensions for specified images

 list($width_x, $height_x) = getimagesize($filename_x);
 list($width_y, $height_y) = getimagesize($filename_y);

 // Create new image with desired dimensions

 $image = imagecreatetruecolor($width_x + $width_y, $height_x);

 // Load images and then copy to destination image

 $image_x = imagecreatefromjpeg($filename_x);
 $image_y = imagecreatefromgif($filename_y);

 imagecopy($image, $image_x, 0, 0, 0, 0, $width_x, $height_x);
 imagecopy($image, $image_y, $width_x, 0, 0, 0, $width_y, $height_y);

 // Save the resulting image to disk (as JPEG)

 imagejpeg($image, $filename_result);

 // Clean up

 imagedestroy($image);
 imagedestroy($image_x);
 imagedestroy($image_y);

}

例：

merge('images/myimg.jpg', 'images/second.gif', 'images/merged.jpg');