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

您可以尝试使用此图像调整大小功能tutorial

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(); 

?>

此外，请参阅此链接以调整图片大小

1。YETANOTHERLinks

2。9Lession

同时转换Base64 for image请参阅此Links

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);
?>

Answer 3

您可以尝试使用imagick - http://php.net/manual/en/imagick.resizeimage.php来调整图像大小。示例代码：要创建缩略图：

<?php

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

?>

Answer 4

如果您使用的是GD代码

<?php
// File and new size
$filename = 'test.jpg';

// Content type
header('Content-Type: image/jpeg');

// Get new sizes
list($width, $height) = getimagesize($filename);
$newwidth = YOUR REQUIRED WIDTH;
$newheight = YOUR REQUIRED HEIGHT;

// Load
$thumb = imagecreatetruecolor($newwidth, $newheight);
$source = imagecreatefromjpeg($filename);

// Resize
imagecopyresized($thumb, $source, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);

// Output
imagejpeg($thumb);
?>

Answer 5

您可以使用例如TimThumb

timthumb.php?src=img.jpg&h=height&w=width

然后你应该将图像编码为base64： How to convert an image to base64 encoding?

Answer 6

帖子有点旧，但如果有人想要，我只是做了这个功能

function save_image_from_64($path, $name, $dimension, $original)
{
    header("Content-Type: image/jpeg");
    list($width,$height) = explode('x',$dimension); //Getting new height and width
    $img = str_replace('data:image/jpeg;base64,', '', $original); //Getting the base64 image
    $image = imagecreatefromstring(base64_decode($img));
    $new_image = imagecreatetruecolor($width, $height);
    imagecopyresampled($new_image, $image, 0, 0, 0, 0, $width, $height, imagesx($image), imagesy($image));
    imagejpeg($new_image, $path.$name.'.jpg'); // saving the image
}

save_image_from_64("cdn/","test","800x200","data:image/jpeg;base64,/9j/4AAQS...");

Answer 7

使用 php LANCZOS

可以更快

$thumb = new Imagick();

$thumb->readImage('XYZ.jpg');

$thumb->resizeImage(640,360,Imagick::FILTER_LANCZOS,1);

$thumb->writeImage('XYZ2.jpg');

$thumb->clear();
$thumb->destroy();

Or Shorter Version ::

$thumb = new Imagick('XYZ.jpg');

$thumb->resizeImage(640,360,Imagick::FILTER_LANCZOS,1);

$thumb->writeImage('XYZ2.jpg');

$thumb->destroy();

如何通过PHP脚本调整图像大小

7 个答案: