Question

我制作了一个PHP脚本，它使用目录中的所有图像动态创建照片库（在http://benxd.me/art/上）。它为每个图像生成缩略图，并为灯箱中的高质量图像添加水印。

但是，我遇到了一个问题：水印脚本和缩略图脚本都会逆时针旋转一个图像（http://benxd.me/assets/img/art/Advance.jpg）90度。

我有其他图片上传到目录，因此这个图片有问题导致它被PHP旋转吗？或者它是由我的脚本引起的？

以下是我的脚本供参考：

engine.php - 生成缩略图的脚本和图库页面上显示的HTML

<?php
/*========================================
  http://www.techrepublic.com/article/create-a-dynamic-photo-gallery-with-php-in-three-steps/
  http://stackoverflow.com/questions/38963849/php-exif-data-not-working
  https://davidwalsh.name/generate-photo-gallery
  ========================================*/
    /* function:  generates thumbnail */
    function make_thumb($src,$dest,$desired_width) {
      /* read the source image */
      $source_image = imagecreatefromjpeg($src);
      $width = imagesx($source_image);
      $height = imagesy($source_image);
      /* find the "desired height" of this thumbnail, relative to the desired width  */
      $desired_height = floor($height*($desired_width/$width));
      /* create a new, "virtual" image */
      $virtual_image = imagecreatetruecolor($desired_width,$desired_height);
      /* copy source image at a resized size */
      imagecopyresized($virtual_image,$source_image,0,0,0,0,$desired_width,$desired_height,$width,$height);
      /* create the physical thumbnail image to its destination */
      imagejpeg($virtual_image,$dest);
    }

    /* function:  returns files from dir */
    function get_files($images_dir,$exts = array('jpg')) {
      $files = array();
      if($handle = opendir($images_dir)) {
        while(false !== ($file = readdir($handle))) {
          $extension = strtolower(get_file_extension($file));
          if($extension && in_array($extension,$exts)) {
            $files[] = $file;
          }
        }
        closedir($handle);
      }
      return $files;
    }

    /* function:  returns a file's extension */
    function get_file_extension($file_name) {
      return substr(strrchr($file_name,'.'),1);
    }

    include("settings.php");

    /** generate photo gallery **/
    $image_files = get_files($images_dir);
    if(count($image_files)) {
      $index = 0;
      foreach($image_files as $index=>$file) {
        $index++;
        $thumbnail_image = $thumbs_dir.$file;
        if(!file_exists($thumbnail_image)) {
          $extension = get_file_extension($thumbnail_image);
          if($extension) {
            make_thumb($images_dir.$file,$thumbnail_image,$thumbs_width);
          }
        }
        // read EXIF headers
        $exif = exif_read_data("$images_dir/$file", "FILE,COMPUTED,ANY_TAG,IFD0,THUMBNAIL,COMMENT,EXIF", true);
        //generate HTML
        echo '<li class="borderless img"><a href="image.php?n=',$file,'" data-lightbox="art" data-title="<b>',str_replace(".jpg", "", $file),'</b> (',$exif['IFD0']['Copyright'],')  ',$exif['IFD0']['ImageDescription'],'"><img src="',$thumbnail_image,'" /></a></li>';
          }
    }
?>

image.php - 为灯箱使用的高质量图片添加水印

<?php
/*========================================
http://gazelleincorporated.com/dynamically-adding-a-watermark-to-an-image-using-php
========================================*/
include("settings.php");
//Let's say you sent the filename via the url, i.e. watermark.php?filename=myimage.jpg
$filename=$_REQUEST['n'];
//get the full path to the image:
$imgpath = $images_dir.$filename;
//OK cool, let's start the process of outputting the image with a watermark...
header('content-type: image/jpeg'); //HTTP header - assumes your images in the gallery are JPGs
//$watermarkfile is the filepath for your watermark image as a PNG-24 Transparent (ex: your logo)
$watermarkfile="../assets/img/copyright-trans.png";
//Get the attributes of the watermark file so you can manipulate it
$watermark = imagecreatefrompng($watermarkfile);
//Get the width and height of your watermark - we will use this to calculate where to put it on the image
list($watermark_width,$watermark_height) = getimagesize($watermarkfile);
//Now get the main gallery image (at $imgpath) so we can maniuplate it
$image = imagecreatefromjpeg($imgpath);
//Get the width and height of your image - we will use this to calculate where the watermark goes
$size = getimagesize($imgpath);
//Calculate where the watermark is positioned
//In this example, it is positioned in the lower right corner, 15px away from the bottom & right edges
$dest_x = ($size[0] - $watermark_width) / 2;
$dest_y = ($size[1] - $watermark_height) / 2;
//I used to use imagecopymerge to apply the watermark to the image
//However it does not preserve the transparency and quality of the watermark
//imagecopymerge($image, $watermark, $dest_x, $dest_y, 0, 0, $watermark_width, $watermark_height, 70);
//So I now use this function which works beautifully:
//Refer here for documentation: http://www.php.net/manual/en/function.imagecopy.php
imagecopy($image, $watermark, $dest_x, $dest_y, 0, 0, $watermark_width, $watermark_height);
//Finalize the image:
imagejpeg($image);
//Destroy the image and the watermark handles
imagedestroy($image);
imagedestroy($watermark);
?>

的settings.php

<?php
$images_dir = '../assets/img/art/';
$thumbs_dir = '../assets/img/art/thumb/';
$thumbs_width = 325;
?>

Answer 1

感谢@MarkSetchell，问题是由图片的exif方向标记引起的。我甚至都不知道存在这样的事情！我能够使用JPEG Autorotate删除exif方向标记。我的脚本现在以正确的方向显示图像。

为什么PHP脚本会将图像放在一边？

1 个答案: