gd就能截了。imagecopyresized — Copy and resize part of an imageDescriptionbool imagecopyresized ( resource $dst_image , resource $src_image , int $dst_x , int $dst_y , int $src_x , int $src_y , int $dst_w , int $dst_h , int $src_w , int $src_h ) imagecopyresized() copies a rectangular portion of one image to another image. dst_image is the destination image, src_image is the source image identifier.In other words, imagecopyresized() will take an 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 (if dst_image is the same as src_image) but if the regions overlap the results will be unpredictable.<?php // File and new size $filename = 'test.jpg'; $percent = 0.5;// Content type header('Content-Type: image/jpeg');// Get new sizes list($width, $height) = getimagesize($filename); $newwidth = $width * $percent; $newheight = $height * $percent;// Load $thumb = imagecreatetruecolor($newwidth, $newheight); $source = imagecreatefromjpeg($filename);// Resize imagecopyresized($thumb, $source, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);// Output imagejpeg($thumb); ?>
imagecopyresized() copies a rectangular portion of one image to another image. dst_image is the destination image, src_image is the source image identifier.In other words, imagecopyresized() will take an 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 (if dst_image is the same as src_image) but if the regions overlap the results will be unpredictable.<?php
// File and new size
$filename = 'test.jpg';
$percent = 0.5;// Content type
header('Content-Type: image/jpeg');// Get new sizes
list($width, $height) = getimagesize($filename);
$newwidth = $width * $percent;
$newheight = $height * $percent;// Load
$thumb = imagecreatetruecolor($newwidth, $newheight);
$source = imagecreatefromjpeg($filename);// Resize
imagecopyresized($thumb, $source, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);// Output
imagejpeg($thumb);
?>
$s = file_get_contents($url);
$ims = imagecreatefromstring($s);$w = imagesx($ims);
$h = imagesy($ims);$imd = imagecreatetruecolor($w/2, $h/2);
imagecopy($imd, $ims, 0, 0, $w/4, $h/4, $w/2, $h/2);
imagepng($imd);