如何通过PHP脚本调整图像大小

Question

我正在创建一个应用程序,需要通过PHP脚本将大图像转换为缩略图,然后将其编码为base64,以便我可以通过json将其发送到我的Android应用程序.我在调整图像大小时遇到​​问题.我需要PHP脚本来帮助我做到这一点

Answer 1

您可以尝试此图像调整大小功能教程

此外,您还可以将此代码用于调整大小功能(GD).

<?php

$thumb = new Imagick();
$thumb->readImage('myimage.gif');    $thumb->resizeImage(320,240,Imagick::FILTER_LANCZOS,1);
$thumb->writeImage('mythumb.gif');
$thumb->clear();
$thumb->destroy(); 

?>

Or, a shorter version of the same:

<?php

$thumb = new Imagick('myimage.gif');

$thumb->resizeImage(320,240,Imagick::FILTER_LANCZOS,1);
$thumb->writeImage('mythumb.gif');

$thumb->destroy(); 

?>

并且还可以参考此链接调整图像大小

1. YETANOTHERLinks

2. 9Lession

并转换Base64 for image请参阅此链接

Answer 2

下面的代码创建了一个名为createThumbs的函数,它将获得三个参数.第一个和第二个相应地是包含原始图像的目录的路径以及放置缩略图的目录的路径.第三个参数是缩略图图像所需的宽度.

<?php
function createThumbs( $pathToImages, $pathToThumbs, $thumbWidth ) 
{
  // open the directory
  $dir = opendir( $pathToImages );

  // loop through it, looking for any/all JPG files:
  while (false !== ($fname = readdir( $dir ))) {
    // parse path for the extension
    $info = pathinfo($pathToImages . $fname);
    // continue only if this is a JPEG image
    if ( strtolower($info['extension']) == 'jpg' ) 
    {
      echo "Creating thumbnail for {$fname} <br />";

      // load image and get image size
      $img = imagecreatefromjpeg( "{$pathToImages}{$fname}" );
      $width = imagesx( $img );
      $height = imagesy( $img );

      // calculate thumbnail size
      $new_width = $thumbWidth;
      $new_height = floor( $height * ( $thumbWidth / $width ) );

      // create a new temporary image
      $tmp_img = imagecreatetruecolor( $new_width, $new_height );

      // copy and resize old image into new image 
      imagecopyresized( $tmp_img, $img, 0, 0, 0, 0, $new_width, $new_height, $width, $height );

      // save thumbnail into a file
      imagejpeg( $tmp_img, "{$pathToThumbs}{$fname}" );
    }
  }
  // close the directory
  closedir( $dir );
}
// call createThumb function and pass to it as parameters the path 
// to the directory that contains images, the path to the directory
// in which thumbnails will be placed and the thumbnail's width. 
// We are assuming that the path will be a relative path working 
// both in the filesystem, and through the web for links
createThumbs("upload/","upload/thumbs/",100);
?>