php 图片剪切

php实现图片剪切，代码如下：

<?php

/**
 * 图像裁剪
 * @param $source_path 原图路径
 * @param $target_width 需要裁剪的宽
 * @param $target_height 需要裁剪的高
 * @return bool
 */
function imagecropper($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;
    }
    $funcList = array(
        'image/gif'  => array(
            'create' => 'imagecreatefromgif',
            'make'   => 'imagegif',
            'mime'   => '.gif',
        ),
        'image/jpeg' => array(
            'create' => 'imagecreatefromjpeg',
            'make'   => 'imagejpeg',
            'mime'   => '.jpg',
        ),
        'image/png'  => array(
            'create' => 'imagecreatefrompng',
            'make'   => 'imagepng',
            'mime'   => '.png',
        ),
    );
    if (isset($funcList[$source_mime])) {
        $curFunc = $funcList[$source_mime];
    } else {
        return FALSE;
    }
    $source_image = $curFunc['create']($source_path);

    $target_image  = imagecreatetruecolor($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);

    //保存图片到本地(两者选一)
    $randNumber = mt_rand(00000, 99999) . mt_rand(000, 999);
    //$fileName   = substr(md5($randNumber), 8, 16) . ".png";
    $fileName = time() . '_' . substr(md5($randNumber), 8, 16) . $curFunc['mime'];
    //imagepng($target_image, './' . $fileName);
    //imagepng($target_image, './' . $fileName);
    //$imgFunc2($target_image, './' . $fileName);
    $curFunc['make']($target_image, './' . $fileName);
    imagedestroy($target_image);

    //直接在浏览器输出图片(两者选一)
    /*header('Content-Type: image/jpeg');
    imagepng($target_image);
    imagedestroy($target_image);
    imagejpeg($target_image);
    imagedestroy($source_image);
    imagedestroy($target_image);
    imagedestroy($cropped_image);*/
}

//调用
//imagecropper('./img033.jpg',300,300);
imagecropper('./4.jpg', 140, 140);
//imagecropper('./img033.jpg',55,55);
?>