GD函数

<?php
    header("content-type:text/html;charset=utf-8");
    $img = imagecreate(100,50) or die('Cannot create GB image');  // 创建画布
    // $img = imagecreatetruecolor(100,50);  // 创建画布
    $img1 = imagecreatefrompng('./png.png');  // 读取图片创建画布

    $background_color = imagecolorallocate($img,mt_rand(200,255),mt_rand(200,255),mt_rand(200,255));  // 设置颜色
    imagefill($img,0,0,$background_color);  // 填充
    $text_color = imagecolorallocate($img,mt_rand(0,140),mt_rand(0,140),mt_rand(0,140));
    $arc_color = imagecolorallocate($img,0,0,0);
    $ellipse_color = imagecolorallocate($img,150,150,150);
    $red_color = imagecolorallocate($img,255,0,0);
    imagerectangle($img,0,0,99,49,$red_color);  // 画矩形
    for($i=0;$i<50;$i++) {
        imagesetpixel($img,mt_rand(0,100),mt_rand(0,50),$red_color);  // 画点
    }
    imagestring($img,5,10,20,' a b c d ',$text_color);  // 写字符串
    imagestringup($img,5,80,50,'efgh',$text_color);  // 写竖字符串
    imagearc($img,0,0,100,50,0,90,$arc_color);  // 画圆
    imagechar($img,3,50,0,'exe',$text_color);  // 写字符
    imagecharup($img,3,50,45,'xex',$text_color);  // 写竖字符
    imageellipse($img,50,25,80,40,$ellipse_color);  // 画曲线
    imagettftext($img,12,0,50,25,$text_color,'simsun.ttc','你好');  // 写文字
    //imagecopy($img1,$img,0,0,0,0,100,50);  // 复制图片到另一张上
    imagecopymerge($img1,$img,0,0,0,0,100,50,50);  // 水印
    //imagecopyresized($thumb, $source, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);  // 图片缩放
    //imagecopyresampled($thumb, $source, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);  // 图片缩放 效果比上面好点
    header("content-type:image/png");
    imagepng($img1);  // 输出图片

    //imagejpeg($thumb,'abc1.jpg');  // 保存图片

    imagedestroy($img);  // 销毁画布资源
    imagedestroy($img1);  // 销毁画布资源
?>

#    array getimagesize( string $filename [, array &$imageinfo ])
#    bool imagearc( resource $image, int $cx, int $cy, int $w, int $h, int $s, int $e, int $color)
#    resource imagecreate( int $x_size, int $y_size)
#    resource imagecreatetruecolor( int $width, int $height)
#    resource imagecreatefromgif( string $filename)
#    resource imagecreatefromjpeg( string $filename)
#    resource imagecreatefrompng( string $filename)
#    int imagecolorallocate( resource $image, int $red, int $green, int $blue)
#    bool imagefill( resource $image, int $x, int $y, int $color)
#    bool imagerectangle( resource $image , int $x1, int $y1, int $x2, int $y2, int $col)
#    bool imagesetpixel( resource $image, int $x, int $y, int $color)
#    bool imagestring( resource $image, int $font, int $x, int $y, string $s, int $col)
#    bool imagestringup( resource $image, int $font, int $x, int $y, string $s, int $col)
#    bool imagearc( resource $image, int $cx, int $cy, int $w, int $h, int $s, int $e, int $color)
#    bool imagefilledarc( resource $image, int $cx, int $cy, int $width, int $height, int $start, int $end, int $color, int $style)
#    bool imagechar( resource $image, int $font, int $x, int $y, string $c, int $color)
#    bool imagecharup( resource $image, int $font, int $x, int $y, string $c, int $color)
#    bool imageellipse( resource $image, int $cx, int $cy, int $width, int $height, int $color)
#    bool imagecopy( resource $dst_im, resource $src_im, int $dst_x, int $dst_y, int $src_x, int $src_y, int $src_w, int $src_h)
#    bool imagecopymerge( resource $dst_im, resource $src_im, int $dst_x, int $dst_y, int $src_x, int $src_y, int $src_w, int $src_h, int $pct)
#    array imagettftext( resource $image, float $size, float $angle, int $x, int $y, int $color, string $fontfile, string $text)
#    bool imagecopyresampled( resource $dst_image, resource $src_image, int $dst_x, int $dst_y, int $src_x, int $src_y, int $dst_w, int $dst_h,
      int $src_w, int $src_h)
#    bool imagecopyresized( resource $dst_image, resource $src_image, int $dst_x, int $dst_y, int $src_x, int $src_y, int $dst_w, int $dst_h, 
      int $src_w, int $src_h)
#    bool imagepng( resource $image [, string $filename  ])
#    bool imagejpeg( resource $image [, string $filename  ])
#    bool imagegif( resource $image [, string $filename  ])
#    bool imagedestroy( resource $image)