使用php7创建png图像

使用 PHP 创建 PNG 图像

<?php
header("Content-type: image/png");
$string = $_GET['text'];
$im     = imagecreatefrompng("images/button1.png");
$orange = imagecolorallocate($im, 220, 210, 60);
$px     = (imagesx($im) - 7.5 * strlen($string)) / 2;
imagestring($im, 3, $px, 9, $string, $orange);
imagepng($im);
imagedestroy($im);
?>

本例程需要从带有<img src="button.php?text=text">标签的页面调用。上述button.php脚本将"text"字符串绘制到一个图像上，在本例中图像文件为"images/button1.png"，然后输出绘制后的图像。当你需要经常修改图像上的文字时，动态生成图像就可以省去了每次都重新制作图像的麻烦。

Function to create random png images when requested for example...
<img src="create_image.php?s=008080_F_1000_200&t=Sample%20Image%20Drawn%20By%20PHP" alt="GD Library Example Image" >
here is create_image.php
<?php
$setting = isset($_GET['s']) ? $_GET['s'] : "FFF_111_100_100";
$setting = explode("_",$setting );
$img = array();
switch ($n = count($setting)) {
  case $n > 4 :
  case 3:
    $setting[3] = $setting[2];
  case 4:
    $img['width'] = (int) $setting[2];
    $img['height'] = (int) $setting[3];
  case 2:
    $img['color'] = $setting[1];
    $img['background'] = $setting[0];
    break;
  default:
    list($img['background'],$img['color'],$img['width'],$img['height']) = array('F','0',100,100);
    break;
}
$background = explode(",",hex2rgb($img['background']));
$color = explode(",",hex2rgb($img['color']));
$width = empty($img['width']) ? 100 : $img['width'];
$height = empty($img['height']) ? 100 : $img['height'];
$string = (string) isset($_GET['t']) ? $_GET['t'] : $width ."x". $height;
header("Content-Type: image/png");
$image = @imagecreate($width, $height)
  or die("Cannot Initialize new GD image stream");
$background_color = imagecolorallocate($image, $background[0], $background[1], $background[2]);
$text_color = imagecolorallocate($image, $color[0], $color[1], $color[2]);
imagestring($image, 5, 5, 5, $string, $text_color);
imagepng($image);
imagedestroy($image);
function hex2rgb($hex) {
  // Copied
  $hex = str_replace("#", "", $hex);
  switch (strlen($hex)) {
    case 1:
      $hex = $hex.$hex;
    case 2:
     $r = hexdec($hex);
     $g = hexdec($hex);
     $b = hexdec($hex);
      break;
    case 3:
     $r = hexdec(substr($hex,0,1).substr($hex,0,1));
     $g = hexdec(substr($hex,1,1).substr($hex,1,1));
     $b = hexdec(substr($hex,2,1).substr($hex,2,1));
      break;
    default:
     $r = hexdec(substr($hex,0,2));
     $g = hexdec(substr($hex,2,2));
     $b = hexdec(substr($hex,4,2));
      break;
  }
  $rgb = array($r, $g, $b);
  return implode(",", $rgb); 
}