我正在拍摄一个源图像，并尝试根据用户选择对其进行裁剪。不过，它总是留下一个黑色的空白，我认为这与我使用的参数顺序不正确有关。在看了imagecopyrasampled（）的php文档之后，我仍然没有找到一种方法来实现这一点。
这是我的东西。我在这个例子中使用了硬编码的值，但每个$targ_变量对每个图像都会发生变化。
$targ_w = 183; // width of cropped selection
$targ_h = 140; // height of cropped selection
$targ_x = 79; // x-coordinate of cropped selection
$targ_y = 59; // y-coordinate of cropped selection
$targ_x2 = 263; // x-coordinate of 2nd point (end of selection)
$targ_y2 = 199; // y-coordinate of 2nd point (end of selection)
$src = '/uploads/test.png';
$img_r = imagecreatefrompng($src);
$dst_r = ImageCreateTrueColor( $targ_w, $targ_h );
imagecopyresampled($dst_r,$img_r,0,0,$targ_x,$targ_y,$targ_x2,$targ_y2,$targ_w,$targ_h);
$newFileName = '/uploads/test2.png';
imagepng($dst_r, $newFileName, 9);
也许只是因为您没有正确计算裁剪区域的尺寸。除此之外，您还使用坐标，其中应使用尺寸标注。比较参数7和8。请注意，这并不能保持透明度。
<?php
$targ_x1 = 59; // x-coordinate of cropped selection
$targ_y1 = 69; // y-coordinate of cropped selection
$targ_x2 = 160; // x-coordinate of 2nd point (end of selection)
$targ_y2 = 82; // y-coordinate of 2nd point (end of selection)
//1st: dynamically calculate the dimensions
$crop_area_width = $targ_x2-$targ_x1; // width of cropped selection
$crop_area_height = $targ_y2-$targ_y1; // height of cropped selection
$image_path = 'http://cdn.sstatic.net/stackoverflow/img/sprites.png';
$src_img = imagecreatefrompng($image_path);
$dst_img = imagecreatetruecolor($crop_area_width, $crop_area_height);
//2nd: cropping does not change scale so source and target dimensions are the same
imagecopyresampled( $dst_img, $src_img, 0, 0, $targ_x1, $targ_y1, $crop_area_width, $crop_area_height, $crop_area_width, $crop_area_height);
header('Content-Type: image/png');
imagepng($dst_img);
?>
请参阅以下URL：-
在没有fopen 的情况下用PHP中的imagecopyresoampled（）裁剪图像
试试这个：-
<?php
function load_file_from_url($url) {
$curl = curl_init();
curl_setopt($curl, CURLOPT_URL, $url);
curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
$str = curl_exec($curl);
curl_close($curl);
return $str;
}
class cropImage{
var $imgSrc,$myImage,$thumb;
function setImage($image) {
//Your Image
$this->imgSrc = $image;
//create image from the jpeg
$this->myImage = imagecreatefromstring($this->imgSrc) or die("Error: Cannot find image!");
$this->thumb = imagecreatetruecolor(200, 112);
//imagecopyresampled($this->thumb, $this->myImage, 0, 0, 0, 45, 200, 112, 480, 270);
imagecopy($this->thumb, $this->myImage, 0, 0, 0, 45, 200, 112, 480, 270);
}
function renderImage()
{
header('Content-type: image/jpeg');
imagejpeg($this->thumb);
imagedestroy($this->thumb);
//imagejpeg($this->myImage);
//imagedestroy($this->myImage);
}
}
$image = new cropImage;
$image->setImage(load_file_from_url($_GET['src']));
$image->renderImage();
?>