首页 > 解决方案 > PHP 中的 ImageMagick Watermark - 如何使用原始图像大小的 % 而不是水印图像大小的 % 来缩放水印?

问题描述

因此,我采用了www.rainbodesign.com中提供的 PHP 代码中的ImageMagick Watermark并对其进行了调整以符合我的需求:在原始图像的右下角添加叠加水印图像。此链接触发转换并返回新的水印图像。这是完整的代码:mywebsite.com/watermark.php?src=filepath-to-image

    <?php
// ImageMagick Watermark in PHP
// Copyright 2010-2011 by Richard L. Trethewey rick@rainbo.net
// http://www.rainbodesign.com/pub/watermark/
// 10/28/11 RLT
// If you use this script, I'd appreciate a link!  Thanks!

// 05/16/11 Updated to support text rotation, top/bottom/center
// 05/28/11 Updated to sanitize inputs
// 10/25/11 Added 'auto' color, inspired by Mikko's Blog http://valokuva.org/?p=59
//          RGB to HSL code by EasyRGB.com and http://serennu.com/colour/rgbtohsl.php

// 11/10/20 Deleted all references to text overlay and its settings
//          Added bottomright support

// Constants
$bContent = "Content-type: image/bmp";   // for BMP files
$jContent = "Content-type: image/jpeg";  // for JPEG files
$gContent = "Content-type: image/gif";   // for GIF files
$pContent = "Content-type: image/png";   // for PNG files
$tContent = "Content-type: image/tiff";  // for TIFF files
$old_image = '';    // Default base image filepath.

// User Settings and Defaults
$wm_image = 'images/watermark.png';     // Default watermark image file (include a path/URL, if necessary)
$wm_type = 'img';               // Set to 'msg' for text watermark.  Set to 'img' for image watermark.
$position = 'bottomright';   // Default watermark position - bottom left corner
$wm_opacity = 80;   // Default watermark image overlay opacity
$wm_rotate = 0;     // Default watermark image overlay rotation (in degrees)
// $gravity = 'SouthWest'; // Default watermark Imagemagick gravity - bottom left corner
$padding = 0;       // Default padding in pixels for watermark positioning.  Both top/bottom and left/right.

// Handle Query String option parameters
// src
 if (isset($_GET['src'])) { $old_image = $_GET['src']; }

// Block script hacking.
 $matches = array();
  if (preg_match('/([;\n\r])/i', $old_image, $matches)) { die; }

  switch(strtolower($position)) {
   case('bottom'):
    $gravity = 'SouthWest';
    break;
   case('bottomcenter'):
    $gravity = 'South';
    break;
   case('bottomright'):
      $gravity = 'SouthEast';
    break;
   case('top'):
    $gravity = 'NorthWest';
    break;
   case('topcenter'):
    $gravity = 'North';
    break;
   case('center'):
    $gravity = 'Center';
    break;
 } // end switch($position)

$dot = strrpos($old_image, '.');    // Set image type based on file name extension.  I know. Sorry, but it's fastest.
$extension = substr($old_image, $dot);
  switch($extension) {
   case('.jpg'):
   case('.jpeg'):
   $theContent = $jContent;
   $theWMType = 'jpg:-';
   break;
   case('.gif'):
   $theContent = $gContent;
   $theWMType = 'gif:-';
   break;
   case('.png'):
   $theContent = $pContent;
   $theWMType = 'png:-';
   break;
   case('.bmp'):
   $theContent = $bContent;
   $theWMType = 'bmp:-';
   break;
   case('.tif'):
   $theContent = $tContent;
   $theWMType = 'tif:-';
   break;
 } // end switch($extension)

// Image Overlay Watermark
 if ($wm_type == 'img') {
  $wmCmd = "convert $wm_image -background transparent -rotate $wm_rotate";
  $wmCmd .= " -scale 35%";
  $wmCmd .= " miff:- |";
  $wmCmd .= " composite -gravity $gravity -geometry +0+0 -blend " . $wm_opacity . "%";
  $wmCmd .= "  - $old_image $theWMType";
  } // endif $wm_type == 'img'

$test = 0; // set to 1 to view ImageMagick command being executed
 if ($test) {
 header('Content-type: text/plain');
 echo("$wmCmd\n");
 die;
}

  header($theContent);
  passthru($wmCmd);  // use passthru() to output binary data

exit;

?>

使用此代码,我设法将水印叠加图像添加到原始图像中。但我需要水印图像是原始图像大小的 35%,而不是水印图像大小的 35%!(当然,水印图像保持其纵横比)

// Image Overlay Watermark
 if ($wm_type == 'img') {
  $wmCmd = "convert $wm_image -background transparent -rotate $wm_rotate";
  $wmCmd .= " -scale 35%"; // here is where I need the magic to happen!
  $wmCmd .= " miff:- |";
  $wmCmd .= " composite -gravity $gravity -geometry +0+0 -blend " . $wm_opacity . "%";
  $wmCmd .= "  - $old_image $theWMType";
  } // endif $wm_type == 'img'

有谁知道如何实现这一目标?提前致谢!!<3

标签: phpimagemagick

解决方案


我将使用 getimagesize() (我知道这是一个 GD 命令)获得原件的大小,并使用其中的宽度来调整水印的大小。

$size = getimagesize($old_image);
$watermakSize = $size[0]*.3; ( you can work out what 35% is )

$wmCmd .= " -resize {$watermakSize}x"; // here is where I need the magic to happen!

还有其他方法,但这是一个简单的方法。

提及您使用的 Imagemagick 版本总是很好。


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