php,gd,创建水印,更改水印文本大小和背景颜色,imagecreatefromjpeg

时间:2010-09-15 18:29:21

标签: php gd watermark

我需要创建一个水印应用于图片并使用不同的名称保存。当前脚本工作得很好但唯一的问题是我需要增加“示例文本”的大小并将背景从黑色更改为白色。我尝试了不同的场景,改变了不透明度,但仍然无法改变背景色。

function watermark($imag_path, $photo_id) {
    // Load the stamp and the photo to apply the watermark to
    $im = imagecreatefromjpeg("$imag_path");
    echo "imag_path is $imag_path and photoid is $photo_id";
    // First we create our stamp image manually from GD
    $stamp = imagecreatetruecolor(490, 20);

    //$im = imagecreatefromjpeg("$photo_id");
    imagestring($stamp, 5, 20, 2, 'sample text', 0xff0000);

    // Set the margins for the stamp and get the height/width of the stamp image
    $marge_right  = 10;
    $marge_bottom = 10;
    $sx           = imagesx($stamp);
    $sy           = imagesy($stamp);

    // Merge the stamp onto our photo with an opacity (transparency) of 100%
    imagecopymerge($im, $stamp, imagesx($im) - $sx - $marge_right, imagesy($im) - $sy - $marge_bottom, 0, 0, imagesx($stamp), imagesy($stamp), 100);
    $new_photo_id = $photo_id . "sample.JPG";
    // Save the image to file and free memory
    imagejpeg($im, "tmp/$new_photo_id");
    imagedestroy($im);
}

2 个答案:

答案 0 :(得分:3)

为什么要使用邮票?我在我的一个网站上使用以下代码:

  $im = imagecreatefromjpeg($path);

  function shadow_text($im, $size, $x, $y, $font, $text)
  {
    $black = imagecolorallocate($im, 0, 0, 0);
    $white = imagecolorallocate($im, 255, 255, 255);
    imagettftext($im, $size, 0, $x + 1, $y + 1, $black, $font, $text);
    imagettftext($im, $size, 0, $x + 0, $y + 1, $black, $font, $text);
    imagettftext($im, $size, 0, $x + 0, $y + 0, $white, $font, $text);
  }

  $font = '../fonts/verdana.ttf';
  $size = 11;

  # calculate maximum height of a character 
  $bbox = imagettfbbox($size, 0, $font, 'ky');
  $x = 8; $y = 8 - $bbox[5];

  $text = 'text to be added';
  shadow_text($im, $size, $x, $y, $font, $text);

  header("Content-Type: image/jpeg");
  imagejpeg($im, null, 90);

此代码运行速度足够快,我们使用它来动态添加动态标签,以便在下载照片时从照片部分添加照片,而不是将其保存到磁盘。

答案 1 :(得分:0)

在我的代码中,我修复了一些常见的错误,例如

1)水印文本位于图像之外

2) PNG和JPG图片错误

所以我计算图像宽度并确定字体大小。因此字体大小是动态的。

所以您只需复制我的方法并将其粘贴到要使用的位置即可。

function waterMark($SourceFile,$ext='png',$WaterMarkText)
{
    if( $ext == "jpg" or  $ext == 'jpeg')
        $image = imagecreatefromjpeg($SourceFile);
    else
        $image = imagecreatefrompng($SourceFile);

    list($width, $height) = getimagesize($SourceFile);
    $font = public_path('fonts/arial.ttf');
    $size = $width*4/100;  // calculating font size based on image width.

    # calculate maximum height of a character
    $bbox = imagettfbbox($size, 0, $font, 'ky');
    $x = 8; $y = 8 - $bbox[5];

    $black = imagecolorallocate($image, 0, 0, 0);
    $white = imagecolorallocate($image, 255, 255, 255);
    imagettftext($image, $size, 0, $x + 1, $y + 1, $black, $font, $WaterMarkText);
    imagettftext($image, $size, 0, $x + 0, $y + 1, $black, $font, $WaterMarkText);
    imagettftext($image, $size, 0, $x + 0, $y + 0, $white, $font, $WaterMarkText);

    //header("Content-Type: image/jpeg");
    // imagejpeg($image, null, 90);

    if ($SourceFile <> '') {
        imagejpeg ($image, $SourceFile, 100);
    } else {
        header('Content-Type: image/jpeg');
        imagejpeg($image, null, 100);
    };
    imagedestroy($image);
  return 1; // you can remove it...
}