上传一个php图片处理类

<?php
class Image {
    private $file;
    private $image;
    private $width;
    private $height;
    private $bits;
    private $mime;

    /**
     * 图片路径
     * Image constructor.
     * @param $file
     */
    public function __construct($file) {
        if (file_exists($file)) {
            $this->file = $file;

            $info = getimagesize($file);

            $this->width  = $info[0];
            $this->height = $info[1];
            $this->bits = isset($info['bits']) ? $info['bits'] : '';
            $this->mime = isset($info['mime']) ? $info['mime'] : '';

            if ($this->mime == 'image/gif') {
                $this->image = imagecreatefromgif($file);
            } elseif ($this->mime == 'image/png') {
                $this->image = imagecreatefrompng($file);
            } elseif ($this->mime == 'image/jpeg') {
                $this->image = imagecreatefromjpeg($file);
            }
        } else {
            exit('Error: Could not load image ' . $file . '!');
        }
    }

    public function getFile() {
        return $this->file;
    }

    public function getImage() {
        return $this->image;
    }

    public function getWidth() {
        return $this->width;
    }

    public function getHeight() {
        return $this->height;
    }

    public function getBits() {
        return $this->bits;
    }

    public function getMime() {
        return $this->mime;
    }

    /**
     * 保存新图片
     * @param $file
     * @param int $quality 图片质量 0 -100 imagepng与imagegif函数都没有第三个参数quality。
     */
    public function save($file, $quality = 90) {
        $info = pathinfo($file);

        $extension = strtolower($info['extension']);

        if (is_resource($this->image)) {
            if ($extension == 'jpeg' || $extension == 'jpg') {
                imagejpeg($this->image, $file, $quality);
            } elseif ($extension == 'png') {
                imagepng($this->image, $file);
            } elseif ($extension == 'gif') {
                imagegif($this->image, $file);
            }
            imagedestroy($this->image);
        }
    }

    /**
     * 设置图像大小
     * @param int $width
     * @param int $height
     * @param string $default 已那个高度或宽度比例为准
     */
    public function resize($width = 0, $height = 0, $default = '') {
        if (!$this->width || !$this->height) {
            return;
        }

        $xpos = 0;
        $ypos = 0;
        $scale = 1;

        $scale_w = $width / $this->width;
        $scale_h = $height / $this->height;

        if ($default == 'w') {
            $scale = $scale_w;
        } elseif ($default == 'h') {
            $scale = $scale_h;
        } else {
            $scale = min($scale_w, $scale_h);
        }

        if ($scale == 1 && $scale_h == $scale_w && $this->mime != 'image/png') {
            return;
        }

        $new_width = (int)($this->width * $scale);
        $new_height = (int)($this->height * $scale);
        $xpos = (int)(($width - $new_width) / 2);
        $ypos = (int)(($height - $new_height) / 2);

        $image_old = $this->image;
        $this->image = imagecreatetruecolor($width, $height);

        if ($this->mime == 'image/png') {
            imagealphablending($this->image, false);
            imagesavealpha($this->image, true);
            $background = imagecolorallocatealpha($this->image, 255, 255, 255, 127);
            imagecolortransparent($this->image, $background);
        } else {
            $background = imagecolorallocate($this->image, 255, 255, 255);
        }

        imagefilledrectangle($this->image, 0, 0, $width, $height, $background);

        imagecopyresampled($this->image, $image_old, $xpos, $ypos, 0, 0, $new_width, $new_height, $this->width, $this->height);
        imagedestroy($image_old);

        $this->width = $width;
        $this->height = $height;
    }

    /**
     * 添加图片水印
     * @param $watermark 水印图片对象
     * @param string $position 水印位置
     */
    public function watermark($watermark, $position = 'bottomright') {
        switch($position) {
            case 'topleft': //左上
                $watermark_pos_x = 0;
                $watermark_pos_y = 0;
                break;
            case 'topright'://右上
                $watermark_pos_x = $this->width - $watermark->getWidth();
                $watermark_pos_y = 0;
                break;
            case 'bottomleft'://左下
                $watermark_pos_x = 0;
                $watermark_pos_y = $this->height - $watermark->getHeight();
                break;
            case 'bottomright'://右下
                $watermark_pos_x = $this->width - $watermark->getWidth();
                $watermark_pos_y = $this->height - $watermark->getHeight();
                break;
        }

        imagecopy($this->image, $watermark->getImage(), $watermark_pos_x, $watermark_pos_y, 0, 0, $watermark->getWidth(), $watermark->getHeight());

        imagedestroy($watermark->getImage());
    }

    /**
     * 裁剪图片有效部分
     * @param $top_x
     * @param $top_y
     * @param $bottom_x
     * @param $bottom_y
     */
    public function crop($top_x, $top_y, $bottom_x, $bottom_y) {
        $image_old = $this->image;
        $this->image = imagecreatetruecolor($bottom_x - $top_x, $bottom_y - $top_y);

        imagecopy($this->image, $image_old, 0, 0, $top_x, $top_y, $this->width, $this->height);
        imagedestroy($image_old);

        $this->width = $bottom_x - $top_x;
        $this->height = $bottom_y - $top_y;
    }

    /**
     * 旋转图片
     * @param $degree
     * @param string $color
     */
    public function rotate($degree, $color = 'FFFFFF') {
        $rgb = $this->html2rgb($color);

        $this->image = imagerotate($this->image, $degree, imagecolorallocate($this->image, $rgb[0], $rgb[1], $rgb[2]));

        $this->width = imagesx($this->image);
        $this->height = imagesy($this->image);
    }

    private function filter() {
        $args = func_get_args();

        call_user_func_array('imagefilter', $args);
    }

    private function text($text, $x = 0, $y = 0, $size = 5, $color = '000000') {
        $rgb = $this->html2rgb($color);

        imagestring($this->image, $size, $x, $y, $text, imagecolorallocate($this->image, $rgb[0], $rgb[1], $rgb[2]));
    }

    /**
     * 合并水印图片
     * @param $merge
     * @param int $x
     * @param int $y
     * @param int $opacity
     */
    private function merge($merge, $x = 0, $y = 0, $opacity = 100) {
        imagecopymerge($this->image, $merge->getImage(), $x, $y, 0, 0, $merge->getWidth(), $merge->getHeight(), $opacity);
    }

    /**
     * 16进制颜色转rgb
     * @param $color
     * @return array|bool
     */
    private function html2rgb($color) {
        if ($color[0] == '#') {
            $color = substr($color, 1);
        }

        if (strlen($color) == 6) {
            list($r, $g, $b) = array($color[0] . $color[1], $color[2] . $color[3], $color[4] . $color[5]);
        } elseif (strlen($color) == 3) {
            list($r, $g, $b) = array($color[0] . $color[0], $color[1] . $color[1], $color[2] . $color[2]);
        } else {
            return false;
        }

        $r = hexdec($r);
        $g = hexdec($g);
        $b = hexdec($b);

        return array($r, $g, $b);
    }
}

$imgpath = "old/1.jpg";
$newimgpath = "new/";
$type = 1;
$image = new Image($imgpath);

$width = $image->getWidth();
$height = $image->getHeight();
//$width $height 为新图片的高度和宽度
$image->resize($width, $height);

//输入新图片
$image->save($newimgpath);