PHP图片裁剪、缩放

根据自定义的目标图, 按目标图高宽比裁剪、缩放源图.

传入参数:

$source_path string 源图路径

$target_width integer 目标图宽度

$target_height integer 目标图高度

支持图片类型: image/gif, image/jpeg, image/png.

function imagecropper($source_path, $target_width, $target_height) { $source_info = getimagesize($source_path); $source_width = $source_info[0]; $source_height = $source_info[1]; $source_mime = $source_info[‘mime’]; $source_ratio = $source_height / $source_width; $target_ratio = $target_height / $target_width; // 源图过高 if ($source_ratio > $target_ratio) { $cropped_width = $source_width; $cropped_height = $source_width * $target_ratio; $source_x = 0; $source_y = ($source_height - $cropped_height) / 2; } // 源图过宽 elseif ($source_ratio < $target_ratio) { $cropped_width = $source_height / $target_ratio; $cropped_height = $source_height; $source_x = ($source_width - $cropped_width) / 2; $source_y = 0; } // 源图适中 else { $cropped_width = $source_width; $cropped_height = $source_height; $source_x = 0; $source_y = 0; } switch ($source_mime) { case ‘image/gif’: $source_image = imagecreatefromgif($source_path); break; case ‘image/jpeg’: $source_image = imagecreatefromjpeg($source_path); break; case ‘image/png’: $source_image = imagecreatefrompng($source_path); break; default: return false; break; } $target_image = imagecreatetruecolor($target_width, $target_height); $cropped_image = imagecreatetruecolor($cropped_width, $cropped_height); // 裁剪 imagecopy($cropped_image, $source_image, 0, 0, $source_x, $source_y, $cropped_width, $cropped_height); // 缩放 imagecopyresampled($target_image, $cropped_image, 0, 0, 0, 0, $target_width, $target_height, $cropped_width, $cropped_height); header(‘Content-Type: image/jpeg’); imagejpeg($target_image); imagedestroy($source_image); imagedestroy($target_image); imagedestroy($cropped_image); }