问题
I am using the following code snippet in order to crop a image?
function crop($width,$height) {
$new_image = imagecreatetruecolor($width, $height);
imagecopyresampled($new_image, $this->image, 0, 0, 0, 0, $this->getWidth(), $this->getHeight(), $width, $height );
$this->image = $new_image;
}
Here, $this->image is the original image $this->getWidth() and $this->getHeight() holds the original dimensions of the picture, where as $width and $height, is the crop area.
But for some reason, the crop image is resized(we can almost say it is resized).
How to fix this?
回答1:
Well, the problem is giving the source dimensions. Giving the dimensions of entire image will re size instead of cropping.
This should solve the problem
function crop($width,$height) {
$new_image = imagecreatetruecolor($width, $height);
imagecopyresampled($new_image, $this->image, 0, 0, 0, 0, $width, $height, $width, $height );
$this->image = $new_image;
}
回答2:
Yes i have a solution for uploaded image crop and resize without starch please Following this steps:
step 1: you make a new index.php file.
<html>
<body>
<form action="image_upload.php" method="POST" enctype="multipart/form-data">
<input type="file" name="image" />
<input type="submit"/>
</form>
</body>
</html>
step 2 : then make a new file resize.php
<?php
Class resize
{
// *** Class variables
private $image;
private $width;
private $height;
private $imageResized;
function __construct($fileName)
{
// *** Open up the file
$this->image = $this->openImage($fileName);
// *** Get width and height
$this->width = imagesx($this->image);
$this->height = imagesy($this->image);
}
## --------------------------------------------------------
public static function openImage($file)
{
// *** Get extension
$extension = strtolower(strrchr($file, '.'));
switch($extension)
{
case '.jpg':
case '.jpeg':
$img = @imagecreatefromjpeg($file);
break;
case '.gif':
$img = @imagecreatefromgif($file);
break;
case '.png':
$img = @imagecreatefrompng($file);
break;
default:
$img = false;
break;
}
return $img;
}
## --------------------------------------------------------
public function resizeImage($newWidth, $newHeight, $option="auto")
{
// *** Get optimal width and height - based on $option
$optionArray = $this->getDimensions($newWidth, $newHeight, $option);
$optimalWidth = $optionArray['optimalWidth'];
$optimalHeight = $optionArray['optimalHeight'];
// *** Resample - create image canvas of x, y size
$this->imageResized = imagecreatetruecolor($optimalWidth, $optimalHeight);
imagecopyresampled($this->imageResized, $this->image, 0, 0, 0, 0, $optimalWidth, $optimalHeight, $this->width, $this->height);
// *** if option is 'crop', then crop too
if ($option == 'crop') {
$this->crop($optimalWidth, $optimalHeight, $newWidth, $newHeight);
}
}
## --------------------------------------------------------
public function getDimensions($newWidth, $newHeight, $option)
{
switch ($option)
{
case 'exact':
$optimalWidth = $newWidth;
$optimalHeight= $newHeight;
break;
case 'portrait':
$optimalWidth = $this->getSizeByFixedHeight($newHeight);
$optimalHeight= $newHeight;
break;
case 'landscape':
$optimalWidth = $newWidth;
$optimalHeight= $this->getSizeByFixedWidth($newWidth);
break;
case 'auto':
$optionArray = $this->getSizeByAuto($newWidth, $newHeight);
$optimalWidth = $optionArray['optimalWidth'];
$optimalHeight = $optionArray['optimalHeight'];
break;
case 'crop':
$optionArray = $this->getOptimalCrop($newWidth, $newHeight);
$optimalWidth = $optionArray['optimalWidth'];
$optimalHeight = $optionArray['optimalHeight'];
break;
}
return array('optimalWidth' => $optimalWidth, 'optimalHeight' => $optimalHeight);
}
## --------------------------------------------------------
public static function getSizeByFixedHeight($newHeight)
{
$ratio = $this->width / $this->height;
$newWidth = $newHeight * $ratio;
return $newWidth;
}
public static function getSizeByFixedWidth($newWidth)
{
$ratio = $this->height / $this->width;
$newHeight = $newWidth * $ratio;
return $newHeight;
}
public static function getSizeByAuto($newWidth, $newHeight)
{
if ($this->height < $this->width)
// *** Image to be resized is wider (landscape)
{
$optimalWidth = $newWidth;
$optimalHeight= $this->getSizeByFixedWidth($newWidth);
}
elseif ($this->height > $this->width)
// *** Image to be resized is taller (portrait)
{
$optimalWidth = $this->getSizeByFixedHeight($newHeight);
$optimalHeight= $newHeight;
}
else
// *** Image to be resizerd is a square
{
if ($newHeight < $newWidth) {
$optimalWidth = $newWidth;
$optimalHeight= $this->getSizeByFixedWidth($newWidth);
} else if ($newHeight > $newWidth) {
$optimalWidth = $this->getSizeByFixedHeight($newHeight);
$optimalHeight= $newHeight;
} else {
// *** Sqaure being resized to a square
$optimalWidth = $newWidth;
$optimalHeight= $newHeight;
}
}
return array('optimalWidth' => $optimalWidth, 'optimalHeight' => $optimalHeight);
}
## --------------------------------------------------------
public function getOptimalCrop($newWidth, $newHeight)
{
$heightRatio = $this->height / $newHeight;
$widthRatio = $this->width / $newWidth;
if ($heightRatio < $widthRatio) {
$optimalRatio = $heightRatio;
} else {
$optimalRatio = $widthRatio;
}
$optimalHeight = $this->height / $optimalRatio;
$optimalWidth = $this->width / $optimalRatio;
return array('optimalWidth' => $optimalWidth, 'optimalHeight' => $optimalHeight);
}
## --------------------------------------------------------
public function crop($optimalWidth, $optimalHeight, $newWidth, $newHeight)
{
// *** Find center - this will be used for the crop
$cropStartX = ( $optimalWidth / 2) - ( $newWidth /2 );
$cropStartY = ( $optimalHeight/ 2) - ( $newHeight/2 );
$crop = $this->imageResized;
//imagedestroy($this->imageResized);
// *** Now crop from center to exact requested size
$this->imageResized = imagecreatetruecolor($newWidth , $newHeight);
imagecopyresampled($this->imageResized, $crop , 0, 0, $cropStartX, $cropStartY, $newWidth, $newHeight , $newWidth, $newHeight);
}
## --------------------------------------------------------
public function saveImage($savePath, $imageQuality="100")
{
// *** Get extension
$extension = strrchr($savePath, '.');
$extension = strtolower($extension);
switch($extension)
{
case '.jpg':
case '.jpeg':
if (imagetypes() & IMG_JPG) {
imagejpeg($this->imageResized, $savePath, $imageQuality);
}
break;
case '.gif':
if (imagetypes() & IMG_GIF) {
imagegif($this->imageResized, $savePath);
}
break;
case '.png':
// *** Scale quality from 0-100 to 0-9
$scaleQuality = round(($imageQuality/100) * 9);
// *** Invert quality setting as 0 is best, not 9
$invertScaleQuality = 9 - $scaleQuality;
if (imagetypes() & IMG_PNG) {
imagepng($this->imageResized, $savePath, $invertScaleQuality);
}
break;
// ... etc
default:
// *** No extension - No save.
break;
}
imagedestroy($this->imageResized);
}
## --------------------------------------------------------
}
?>
step 3 : you also make a new two folder 1) image and 2) image_thumb
step 4 : then after make a new file image_upload.php
<?php
include('resize.php');
if(isset($_FILES['image'])){
//set a folder move to orignal images
$destinationPath = "image/";
//set a folder move to crop and resizeable images
$destinationThumbPath = "image_thumb/";
//uploaded files extension
$extension = strtolower(strrchr($_FILES['image']['name'], '.'));
//set a new custom name of uploaded file
$file_name = "image_".rand('1111','9999').$extension;
//move orignal image in Destination Path
move_uploaded_file($_FILES['image']['tmp_name'],"image/".$file_name);
//set a new thumbnail width
$newWidth = 96;
//set a new thumbnail height
$newHeight = 96;
//profile image resize
$resizeObj = new resize($destinationPath . $file_name);
// *** 2) Resize image (options: exact, portrait, landscape, auto, crop)
$resizeObj->resizeImage($newWidth, $newHeight, 'crop');
//crop and resize image save in destination path
$resizeObj->saveImage($destinationThumbPath . $file_name, 100);
}
?>
回答3:
This is what imagecopyresampled does: it rescales the image and does not crop it. Try imagecopy instead.
来源：https://stackoverflow.com/questions/3053381/why-does-my-image-stretch-when-i-crop-it