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在 PHP 中裁剪图像

发布于 2024-08-13 09:43:50 字数 553 浏览 6 评论 0原文

下面的代码可以很好地裁剪图像，这正是我想要的，但对于较大的图像，它也不起作用。有没有什么方法可以“缩小图像”

理想情况下，我可以在裁剪之前使每个图像的大小大致相同，这样每次

代码都可以得到很好的结果

<?php

$image = $_GET['src']; // the image to crop
$dest_image = 'images/cropped_whatever.jpg'; // make sure the directory is writeable

$img = imagecreatetruecolor('200','150');
$org_img = imagecreatefromjpeg($image);
$ims = getimagesize($image);
imagecopy($img,$org_img, 0, 0, 20, 20, 200, 150);
imagejpeg($img,$dest_image,90);
imagedestroy($img);
echo '<img src="'.$dest_image.'" ><p>';
原文

The code below crops the image well, which is what i want, but for larger images, it wotn work as well. Is there any way of 'zooming out of the image'

Idealy i would be able to have each image roughly the same size before cropping so that i would get good results each time

Code is

<?php

$image = $_GET['src']; // the image to crop
$dest_image = 'images/cropped_whatever.jpg'; // make sure the directory is writeable

$img = imagecreatetruecolor('200','150');
$org_img = imagecreatefromjpeg($image);
$ims = getimagesize($image);
imagecopy($img,$org_img, 0, 0, 20, 20, 200, 150);
imagejpeg($img,$dest_image,90);
imagedestroy($img);
echo '<img src="'.$dest_image.'" ><p>';

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评论（8）

似梦非梦 2024-08-20 09:43:50

如果您尝试生成缩略图，则必须首先使用imagecopyresampled();调整图像大小。您必须调整图像大小，使图像较小一侧的大小等于拇指相应一侧的大小。

例如，如果您的源图像为 1280x800 像素，而您的拇指为 200x150 像素，则必须将图像大小调整为 240x150 像素，然后将其裁剪为 200x150 像素。这样图像的纵横比就不会改变。

以下是创建缩略图的一般公式：

$image = imagecreatefromjpeg($_GET['src']);
$filename = 'images/cropped_whatever.jpg';

$thumb_width = 200;
$thumb_height = 150;

$width = imagesx($image);
$height = imagesy($image);

$original_aspect = $width / $height;
$thumb_aspect = $thumb_width / $thumb_height;

if ( $original_aspect >= $thumb_aspect )
{
   // If image is wider than thumbnail (in aspect ratio sense)
   $new_height = $thumb_height;
   $new_width = $width / ($height / $thumb_height);
}
else
{
   // If the thumbnail is wider than the image
   $new_width = $thumb_width;
   $new_height = $height / ($width / $thumb_width);
}

$thumb = imagecreatetruecolor( $thumb_width, $thumb_height );

// Resize and crop
imagecopyresampled($thumb,
                   $image,
                   0 - ($new_width - $thumb_width) / 2, // Center the image horizontally
                   0 - ($new_height - $thumb_height) / 2, // Center the image vertically
                   0, 0,
                   $new_width, $new_height,
                   $width, $height);
imagejpeg($thumb, $filename, 80);

尚未对此进行测试，但它应该可以工作。

编辑

现已测试并正常工作。

If you are trying to generate thumbnails, you must first resize the image using imagecopyresampled();. You must resize the image so that the size of the smaller side of the image is equal to the corresponding side of the thumb.

For example, if your source image is 1280x800px and your thumb is 200x150px, you must resize your image to 240x150px and then crop it to 200x150px. This is so that the aspect ratio of the image won't change.

Here's a general formula for creating thumbnails:

$image = imagecreatefromjpeg($_GET['src']);
$filename = 'images/cropped_whatever.jpg';

$thumb_width = 200;
$thumb_height = 150;

$width = imagesx($image);
$height = imagesy($image);

$original_aspect = $width / $height;
$thumb_aspect = $thumb_width / $thumb_height;

if ( $original_aspect >= $thumb_aspect )
{
   // If image is wider than thumbnail (in aspect ratio sense)
   $new_height = $thumb_height;
   $new_width = $width / ($height / $thumb_height);
}
else
{
   // If the thumbnail is wider than the image
   $new_width = $thumb_width;
   $new_height = $height / ($width / $thumb_width);
}

$thumb = imagecreatetruecolor( $thumb_width, $thumb_height );

// Resize and crop
imagecopyresampled($thumb,
                   $image,
                   0 - ($new_width - $thumb_width) / 2, // Center the image horizontally
                   0 - ($new_height - $thumb_height) / 2, // Center the image vertically
                   0, 0,
                   $new_width, $new_height,
                   $width, $height);
imagejpeg($thumb, $filename, 80);

Haven't tested this but it should work.

EDIT

Now tested and working.

回复 原文
极度宠爱 2024-08-20 09:43:50

imagecopyresampled() 将从 $src_image 中获取宽度 $src_w 和高度 $src_h 的矩形区域，位置 < code>($src_x, $src_y) 并将其放置在宽度 $dst_w 和高度 $dst_h 的 $dst_image 矩形区域中code> 位于 ($dst_x, $dst_y) 位置。

如果源坐标和目标坐标以及宽度和高度不同，则会对图像片段进行适当的拉伸或收缩。坐标指的是左上角。

此功能可用于复制同一图像内的区域。但如果区域重叠，结果将难以预测。

- 编辑 -

如果$src_w和$src_h分别小于$dst_w和$dst_h，缩略图将放大。否则将缩小。

<?php
$dst_x = 0;   // X-coordinate of destination point
$dst_y = 0;   // Y-coordinate of destination point
$src_x = 100; // Crop Start X position in original image
$src_y = 100; // Crop Srart Y position in original image
$dst_w = 160; // Thumb width
$dst_h = 120; // Thumb height
$src_w = 260; // Crop end X position in original image
$src_h = 220; // Crop end Y position in original image

// Creating an image with true colors having thumb dimensions (to merge with the original image)
$dst_image = imagecreatetruecolor($dst_w, $dst_h);
// Get original image
$src_image = imagecreatefromjpeg('images/source.jpg');
// Cropping
imagecopyresampled($dst_image, $src_image, $dst_x, $dst_y, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h);
// Saving
imagejpeg($dst_image, 'images/crop.jpg');
?>

imagecopyresampled() will take a rectangular area from $src_image of width $src_w and height $src_h at position ($src_x, $src_y) and place it in a rectangular area of $dst_image of width $dst_w and height $dst_h at position ($dst_x, $dst_y).

If the source and destination coordinates and width and heights differ, appropriate stretching or shrinking of the image fragment will be performed. The coordinates refer to the upper left corner.

This function can be used to copy regions within the same image. But if the regions overlap, the results will be unpredictable.

- Edit -

If $src_w and $src_h are smaller than $dst_w and $dst_h respectively, thumb image will be zoomed in. Otherwise it will be zoomed out.

<?php
$dst_x = 0;   // X-coordinate of destination point
$dst_y = 0;   // Y-coordinate of destination point
$src_x = 100; // Crop Start X position in original image
$src_y = 100; // Crop Srart Y position in original image
$dst_w = 160; // Thumb width
$dst_h = 120; // Thumb height
$src_w = 260; // Crop end X position in original image
$src_h = 220; // Crop end Y position in original image

// Creating an image with true colors having thumb dimensions (to merge with the original image)
$dst_image = imagecreatetruecolor($dst_w, $dst_h);
// Get original image
$src_image = imagecreatefromjpeg('images/source.jpg');
// Cropping
imagecopyresampled($dst_image, $src_image, $dst_x, $dst_y, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h);
// Saving
imagejpeg($dst_image, 'images/crop.jpg');
?>
回复 原文
晨曦慕雪 2024-08-20 09:43:50

php 5.5 有一个 imagecrop 函数 http://php.net/manual/en/function.imagecrop .php

php 5.5 has an imagecrop function http://php.net/manual/en/function.imagecrop.php

回复 原文
撩起发的微风 2024-08-20 09:43:50
$image = imagecreatefromjpeg($_GET['src']);

需要替换为：

$image = imagecreatefromjpeg('images/thumbnails/myimage.jpg');

因为 imagecreatefromjpeg() 需要一个字符串。
这对我有用。

参考：
http://php.net/manual/en/function.imagecreatefromjpeg.php

$image = imagecreatefromjpeg($_GET['src']);

Needs to be replaced with this:

$image = imagecreatefromjpeg('images/thumbnails/myimage.jpg');

Because imagecreatefromjpeg() is expecting a string.
This worked for me.

ref:
http://php.net/manual/en/function.imagecreatefromjpeg.php

回复 原文
旧人 2024-08-20 09:43:50

HTML 代码：-

enter code here
  <!DOCTYPE html>
  <html>
  <body>

  <form action="upload.php" method="post" enctype="multipart/form-data">
  Select image to upload:
  <input type="file" name="image" id="fileToUpload">
  <input type="submit" value="Upload Image" name="submit">
 </form>

 </body>
 </html>

upload.php

enter code here
<?php 
      $image = $_FILES;
      $NewImageName = rand(4,10000)."-". $image['image']['name'];
      $destination = realpath('../images/testing').'/';
      move_uploaded_file($image['image']['tmp_name'], $destination.$NewImageName);
      $image = imagecreatefromjpeg($destination.$NewImageName);
      $filename = $destination.$NewImageName;

      $thumb_width = 200;
      $thumb_height = 150;

      $width = imagesx($image);
      $height = imagesy($image);

      $original_aspect = $width / $height;
      $thumb_aspect = $thumb_width / $thumb_height;

      if ( $original_aspect >= $thumb_aspect )
      {
         // If image is wider than thumbnail (in aspect ratio sense)
         $new_height = $thumb_height;
         $new_width = $width / ($height / $thumb_height);
      }
      else
      {
         // If the thumbnail is wider than the image
         $new_width = $thumb_width;
         $new_height = $height / ($width / $thumb_width);
      }

      $thumb = imagecreatetruecolor( $thumb_width, $thumb_height );

      // Resize and crop
      imagecopyresampled($thumb,
                         $image,
                         0 - ($new_width - $thumb_width) / 2, // Center the image horizontally
                         0 - ($new_height - $thumb_height) / 2, // Center the image vertically
                         0, 0,
                         $new_width, $new_height,
                         $width, $height);
      imagejpeg($thumb, $filename, 80);
      echo "cropped"; die;
      ?>

HTML Code:-

enter code here
  <!DOCTYPE html>
  <html>
  <body>

  <form action="upload.php" method="post" enctype="multipart/form-data">
  Select image to upload:
  <input type="file" name="image" id="fileToUpload">
  <input type="submit" value="Upload Image" name="submit">
 </form>

 </body>
 </html>

upload.php

enter code here
<?php 
      $image = $_FILES;
      $NewImageName = rand(4,10000)."-". $image['image']['name'];
      $destination = realpath('../images/testing').'/';
      move_uploaded_file($image['image']['tmp_name'], $destination.$NewImageName);
      $image = imagecreatefromjpeg($destination.$NewImageName);
      $filename = $destination.$NewImageName;

      $thumb_width = 200;
      $thumb_height = 150;

      $width = imagesx($image);
      $height = imagesy($image);

      $original_aspect = $width / $height;
      $thumb_aspect = $thumb_width / $thumb_height;

      if ( $original_aspect >= $thumb_aspect )
      {
         // If image is wider than thumbnail (in aspect ratio sense)
         $new_height = $thumb_height;
         $new_width = $width / ($height / $thumb_height);
      }
      else
      {
         // If the thumbnail is wider than the image
         $new_width = $thumb_width;
         $new_height = $height / ($width / $thumb_width);
      }

      $thumb = imagecreatetruecolor( $thumb_width, $thumb_height );

      // Resize and crop
      imagecopyresampled($thumb,
                         $image,
                         0 - ($new_width - $thumb_width) / 2, // Center the image horizontally
                         0 - ($new_height - $thumb_height) / 2, // Center the image vertically
                         0, 0,
                         $new_width, $new_height,
                         $width, $height);
      imagejpeg($thumb, $filename, 80);
      echo "cropped"; die;
      ?>
回复 原文
眼波传意 2024-08-20 09:43:50

改进了 PHP 中的动态裁剪图像功能。

http://www.example.com/cropimage.php?filename=a.jpg&newxsize=100&newysize=200&constrain=1

cropimage.php 中的代码

$basefilename = @basename(urldecode($_REQUEST['filename']));

$path = 'images/';
$outPath = 'crop_images/';
$saveOutput = false; // true/false ("true" if you want to save images in out put folder)
$defaultImage = 'no_img.png'; // change it with your default image

$basefilename = $basefilename;
$w = $_REQUEST['newxsize'];
$h = $_REQUEST['newysize'];

if ($basefilename == "") {
    $img = $path . $defaultImage;
    $percent = 100;
} else {
    $img = $path . $basefilename;

    $len = strlen($img);
    $ext = substr($img, $len - 3, $len);
    $img2 = substr($img, 0, $len - 3) . strtoupper($ext);
    if (!file_exists($img)) $img = $img2;
    if (file_exists($img)) {
        $percent = @$_GET['percent'];
        $constrain = @$_GET['constrain'];
        $w = $w;
        $h = $h;
    } else if (file_exists($path . $basefilename)) {
        $img = $path . $basefilename;
        $percent = $_GET['percent'];
        $constrain = $_GET['constrain'];
        $w = $w;
        $h = $h;
    } else {

        $img = $path . 'no_img.png';    // change with your default image
        $percent = @$_GET['percent'];
        $constrain = @$_GET['constrain'];
        $w = $w;
        $h = $h;

    }

}

// get image size of img
$x = @getimagesize($img);

// image width
$sw = $x[0];
// image height
$sh = $x[1];

if ($percent > 0) {
    // calculate resized height and width if percent is defined
    $percent = $percent * 0.01;
    $w = $sw * $percent;
    $h = $sh * $percent;
} else {
    if (isset ($w) AND !isset ($h)) {
        // autocompute height if only width is set
        $h = (100 / ($sw / $w)) * .01;
        $h = @round($sh * $h);
    } elseif (isset ($h) AND !isset ($w)) {
        // autocompute width if only height is set
        $w = (100 / ($sh / $h)) * .01;
        $w = @round($sw * $w);
    } elseif (isset ($h) AND isset ($w) AND isset ($constrain)) {
        // get the smaller resulting image dimension if both height
        // and width are set and $constrain is also set
        $hx = (100 / ($sw / $w)) * .01;
        $hx = @round($sh * $hx);

        $wx = (100 / ($sh / $h)) * .01;
        $wx = @round($sw * $wx);

        if ($hx < $h) {
            $h = (100 / ($sw / $w)) * .01;
            $h = @round($sh * $h);
        } else {
            $w = (100 / ($sh / $h)) * .01;
            $w = @round($sw * $w);
        }
    }
}

$im = @ImageCreateFromJPEG($img) or // Read JPEG Image
$im = @ImageCreateFromPNG($img) or // or PNG Image
$im = @ImageCreateFromGIF($img) or // or GIF Image
$im = false; // If image is not JPEG, PNG, or GIF

if (!$im) {
    // We get errors from PHP's ImageCreate functions...
    // So let's echo back the contents of the actual image.
    readfile($img);
} else {
    // Create the resized image destination
    $thumb = @ImageCreateTrueColor($w, $h);
    // Copy from image source, resize it, and paste to image destination
    @ImageCopyResampled($thumb, $im, 0, 0, 0, 0, $w, $h, $sw, $sh);

    //Other format imagepng()

    if ($saveOutput) { //Save image
        $save = $outPath . $basefilename;
        @ImageJPEG($thumb, $save);
    } else { // Output resized image
        header("Content-type: image/jpeg");
        @ImageJPEG($thumb);
    }
}

Improved Crop image functionality in PHP on the fly.

http://www.example.com/cropimage.php?filename=a.jpg&newxsize=100&newysize=200&constrain=1

Code in cropimage.php

$basefilename = @basename(urldecode($_REQUEST['filename']));

$path = 'images/';
$outPath = 'crop_images/';
$saveOutput = false; // true/false ("true" if you want to save images in out put folder)
$defaultImage = 'no_img.png'; // change it with your default image

$basefilename = $basefilename;
$w = $_REQUEST['newxsize'];
$h = $_REQUEST['newysize'];

if ($basefilename == "") {
    $img = $path . $defaultImage;
    $percent = 100;
} else {
    $img = $path . $basefilename;

    $len = strlen($img);
    $ext = substr($img, $len - 3, $len);
    $img2 = substr($img, 0, $len - 3) . strtoupper($ext);
    if (!file_exists($img)) $img = $img2;
    if (file_exists($img)) {
        $percent = @$_GET['percent'];
        $constrain = @$_GET['constrain'];
        $w = $w;
        $h = $h;
    } else if (file_exists($path . $basefilename)) {
        $img = $path . $basefilename;
        $percent = $_GET['percent'];
        $constrain = $_GET['constrain'];
        $w = $w;
        $h = $h;
    } else {

        $img = $path . 'no_img.png';    // change with your default image
        $percent = @$_GET['percent'];
        $constrain = @$_GET['constrain'];
        $w = $w;
        $h = $h;

    }

}

// get image size of img
$x = @getimagesize($img);

// image width
$sw = $x[0];
// image height
$sh = $x[1];

if ($percent > 0) {
    // calculate resized height and width if percent is defined
    $percent = $percent * 0.01;
    $w = $sw * $percent;
    $h = $sh * $percent;
} else {
    if (isset ($w) AND !isset ($h)) {
        // autocompute height if only width is set
        $h = (100 / ($sw / $w)) * .01;
        $h = @round($sh * $h);
    } elseif (isset ($h) AND !isset ($w)) {
        // autocompute width if only height is set
        $w = (100 / ($sh / $h)) * .01;
        $w = @round($sw * $w);
    } elseif (isset ($h) AND isset ($w) AND isset ($constrain)) {
        // get the smaller resulting image dimension if both height
        // and width are set and $constrain is also set
        $hx = (100 / ($sw / $w)) * .01;
        $hx = @round($sh * $hx);

        $wx = (100 / ($sh / $h)) * .01;
        $wx = @round($sw * $wx);

        if ($hx < $h) {
            $h = (100 / ($sw / $w)) * .01;
            $h = @round($sh * $h);
        } else {
            $w = (100 / ($sh / $h)) * .01;
            $w = @round($sw * $w);
        }
    }
}

$im = @ImageCreateFromJPEG($img) or // Read JPEG Image
$im = @ImageCreateFromPNG($img) or // or PNG Image
$im = @ImageCreateFromGIF($img) or // or GIF Image
$im = false; // If image is not JPEG, PNG, or GIF

if (!$im) {
    // We get errors from PHP's ImageCreate functions...
    // So let's echo back the contents of the actual image.
    readfile($img);
} else {
    // Create the resized image destination
    $thumb = @ImageCreateTrueColor($w, $h);
    // Copy from image source, resize it, and paste to image destination
    @ImageCopyResampled($thumb, $im, 0, 0, 0, 0, $w, $h, $sw, $sh);

    //Other format imagepng()

    if ($saveOutput) { //Save image
        $save = $outPath . $basefilename;
        @ImageJPEG($thumb, $save);
    } else { // Output resized image
        header("Content-type: image/jpeg");
        @ImageJPEG($thumb);
    }
}
回复 原文
梦回梦里 2024-08-20 09:43:50

您可以在 ( PHP 5 >= 5.5.0，PHP 7)

示例：

<?php
$im = imagecreatefrompng('example.png');
$size = min(imagesx($im), imagesy($im));
$im2 = imagecrop($im, ['x' => 0, 'y' => 0, 'width' => $size, 'height' => $size]);
if ($im2 !== FALSE) {
    imagepng($im2, 'example-cropped.png');
    imagedestroy($im2);
}
imagedestroy($im);
?>

You can use imagecrop function in (PHP 5 >= 5.5.0, PHP 7)

Example:

<?php
$im = imagecreatefrompng('example.png');
$size = min(imagesx($im), imagesy($im));
$im2 = imagecrop($im, ['x' => 0, 'y' => 0, 'width' => $size, 'height' => $size]);
if ($im2 !== FALSE) {
    imagepng($im2, 'example-cropped.png');
    imagedestroy($im2);
}
imagedestroy($im);
?>
回复 原文
狼亦尘 2024-08-20 09:43:50
$image = imagecreatefromjpeg($_GET['src']);
$filename = 'images/cropped_whatever.jpg'

必须替换为：

$image = imagecreatefromjpeg($_GET['src']);

然后就可以了！

$image = imagecreatefromjpeg($_GET['src']);
$filename = 'images/cropped_whatever.jpg'

Must be replaced with:

$image = imagecreatefromjpeg($_GET['src']);

Then it will work!

回复 原文
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