在 PHP 中裁剪图像
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Crop image in PHP
提问by user195257
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'
下面的代码可以很好地裁剪图像，这正是我想要的，但是对于较大的图像，它也可以正常工作。有没有办法“缩小图像”
Idealy i would be able to have each image roughly the same size before cropping so that i would get good results each time
理想情况下，我可以在裁剪前使每个图像的大小大致相同，以便每次都能获得良好的效果
Code is
代码是
<?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>';
回答by Tatu Ulmanen
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.
如果您要尝试生成缩略图，则必须首先使用 调整图像大小imagecopyresampled();。您必须调整图像大小，使图像较小边的大小等于拇指对应边的大小。
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.
例如，如果您的源图像是 1280x800 像素而您的拇指是 200x150 像素，则您必须将图像大小调整为 240x150 像素，然后将其裁剪为 200x150 像素。这是为了图像的纵横比不会改变。
Here's a general formula for creating thumbnails:
这是创建缩略图的通用公式：
$image = imagecreatefromjpeg($_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);
Haven't tested this but it shouldwork.
尚未对此进行测试，但它应该可以工作。
EDIT
编辑
Now tested and working.
现在测试和工作。
回答by Eranda
imagecopyresampled()will take a rectangular area from $src_imageof width $src_wand height $src_hat position ($src_x, $src_y)and place it in a rectangular area of $dst_imageof width $dst_wand height $dst_hat position ($dst_x, $dst_y).
imagecopyresampled()将采取的矩形区域从$src_image宽度$src_w和高度$src_h在位置($src_x, $src_y)，并将其放置在一个矩形区域$dst_image的宽度$dst_w和高度$dst_h在位置($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.
如果源和目标坐标以及宽度和高度不同，将执行图像片段的适当拉伸或收缩。坐标是指左上角。
This function can be used to copy regions within the same image. But if the regions overlap, the results will be unpredictable.
此功能可用于复制同一图像内的区域。但如果区域重叠，结果将是不可预测的。
- Edit -
- 编辑 -
If $src_wand $src_hare smaller than $dst_wand $dst_hrespectively, thumb image will be zoomed in. Otherwise it will be zoomed out.
如果$src_w和$src_h分别小于$dst_w和$dst_h，则拇指图像将被放大。否则将被缩小。
<?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');
?>
回答by giorgio79
php 5.5 has an imagecrop function http://php.net/manual/en/function.imagecrop.php
php 5.5 有 imagecrop 功能http://php.net/manual/en/function.imagecrop.php
回答by Nadeem0035
Improved Crop image functionality in PHP on the fly.
改进了 PHP 中的即时裁剪图像功能。
http://www.example.com/cropimage.php?filename=a.jpg&newxsize=100&newysize=200&constrain=1
Code in cropimage.php
输入代码 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);
}
}
回答by Nabi K.A.Z.
You can use imagecropfunction in (PHP 5 >= 5.5.0, PHP 7)
您可以imagecrop在 (PHP 5 >= 5.5.0, PHP 7) 中使用函数
Example:
例子：
<?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);
?>
回答by Nabi K.A.Z.
HTML Code:-
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
上传.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;
?>
回答by Harry Fairbanks
$image = imagecreatefromjpeg($_GET['src']);
Needs to be replaced with this:
需要用这个替换：
$image = imagecreatefromjpeg('images/thumbnails/myimage.jpg');
Because imagecreatefromjpeg()is expecting a string.
This worked for me.
因为imagecreatefromjpeg()正在等待一个字符串。
这对我有用。
ref:
http://php.net/manual/en/function.imagecreatefromjpeg.php
参考：http :
//php.net/manual/en/function.imagecreatefromjpeg.php
回答by paris
$image = imagecreatefromjpeg($_GET['src']);
$filename = 'images/cropped_whatever.jpg'
Must be replaced with:
必须替换为：
$image = imagecreatefromjpeg($_GET['src']);
Then it will work!
然后它会起作用！
