Merge pull request #1273 from hsoftxl/gif-captcha

图片验证码

hutool-captcha/src/main/java/cn/hutool/captcha/CaptchaUtil.java

@@ -83,4 +83,12 @@ public class CaptchaUtil {
     public static ShearCaptcha createShearCaptcha(int width, int height, int codeCount, int thickness) {
         return new ShearCaptcha(width, height, codeCount, thickness);
     }
+
+    public static GifCaptcha createGifCaptcha(int width, int height) {
+        return new GifCaptcha(width, height);
+    }
+
+    public static GifCaptcha createGifCaptcha(int width, int height, int delay) {
+        return new GifCaptcha(width, height, delay);
+    }
 }

hutool-captcha/src/main/java/cn/hutool/captcha/GifCaptcha.java

@@ -0,0 +1,221 @@
+package cn.hutool.captcha;
+
+
+import cn.hutool.core.img.gif.AnimatedGifEncoder;
+import cn.hutool.core.util.ObjectUtil;
+
+import java.awt.*;
+import java.awt.image.BufferedImage;
+import java.io.ByteArrayOutputStream;
+import java.util.Random;
+
+/**
+ * Gif验证码类
+ */
+public class GifCaptcha extends AbstractCaptcha {
+    private static final long serialVersionUID = 7091627304326538464L;
+
+    private final Random RANDOM = new Random();
+    // 帧延迟 (默认100)
+    private int delay = 100;
+    //量化器取样间隔 - 默认是10ms
+    private int quality = 10;
+    // 帧循环次数
+    private int repeat = 0;
+    //设置随机颜色时，最小的取色范围
+    private int minColor = 0;
+    //设置随机颜色时，最大的取色范围
+    private int maxColor = 255;
+
+
+    /**
+     * 可以设置验证码宽度，高度的构造函数
+     *
+     * @param width  -验证码宽度
+     * @param height -验证码高度
+     */
+    public GifCaptcha(int width, int height) {
+        this(width, height, 100);
+    }
+
+    /**
+     * @param width     -验证码宽度
+     * @param height    -验证码高度
+     * @param codeCount -验证码个数
+     */
+    public GifCaptcha(int width, int height, int codeCount) {
+        super(width, height, codeCount, 10);
+    }
+
+    /**
+     * 设置图像的颜色量化(转换质量 由GIF规范允许的最大256种颜色)。
+     * 低的值(最小值= 1)产生更好的颜色,但处理显著缓慢。
+     * 10是默认,并产生良好的颜色而且有以合理的速度。
+     * 值更大(大于20)不产生显著的改善速度
+     *
+     * @param quality 大于1
+     */
+    public void setQuality(int quality) {
+        if (quality < 1) {
+            quality = 1;
+        }
+        this.quality = quality;
+    }
+
+    /**
+     * 设置GIF帧应该播放的次数。
+     * 默认是 0; 0意味着无限循环。
+     * 必须在添加的第一个图像之前被调用。
+     *
+     * @param repeat 必须大于等于0
+     */
+    public void setRepeat(int repeat) {
+        if (repeat >= 0) {
+            this.repeat = repeat;
+        }
+    }
+
+    /**
+     * 设置验证码字符颜色
+     *
+     * @param maxColor 颜色
+     */
+    public void setMaxColor(int maxColor) {
+        this.maxColor = maxColor;
+    }
+
+    /**
+     * 设置验证码字符颜色
+     *
+     * @param minColor 颜色
+     */
+    public void setMinColor(int minColor) {
+        this.minColor = minColor;
+    }
+
+    @Override
+    public void createCode() {
+        generateCode();
+        final ByteArrayOutputStream out = new ByteArrayOutputStream();
+
+        AnimatedGifEncoder gifEncoder = new AnimatedGifEncoder();// gif编码类
+        //生成字符
+        gifEncoder.start(out);
+        gifEncoder.setQuality(quality);//设置量化器取样间隔
+        gifEncoder.setDelay(delay);//设置帧延迟
+        gifEncoder.setRepeat(repeat);//帧循环次数
+        BufferedImage frame;
+        char[] chars = code.toCharArray();
+        Color[] fontColor = new Color[chars.length];
+        for (int i = 0; i < chars.length; i++) {
+            fontColor[i] = getRandomColor(minColor, maxColor);
+            frame = graphicsImage(chars, fontColor, chars, i);
+            gifEncoder.addFrame(frame);
+            frame.flush();
+        }
+        gifEncoder.finish();
+        this.imageBytes = out.toByteArray();
+    }
+
+    @Override
+    protected Image createImage(String code) {
+        return null;
+    }
+
+    /**
+     * 画随机码图
+     *
+     * @param fontColor 随机字体颜色
+     * @param words     字符数组
+     * @param flag      透明度使用
+     * @return BufferedImage
+     */
+    private BufferedImage graphicsImage(char[] chars, Color[] fontColor, char[] words, int flag) {
+        BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
+        //或得图形上下文
+        Graphics2D g2d = image.createGraphics();
+        //利用指定颜色填充背景
+        g2d.setColor(ObjectUtil.defaultIfNull(this.background, Color.WHITE));
+        g2d.fillRect(0, 0, width, height);
+        AlphaComposite ac;
+        // 字符的y坐标
+        float y = (height >> 1) + (font.getSize() >> 1);
+        float m = 1.0f * (width - (chars.length * font.getSize())) / chars.length;
+        //字符的x坐标
+        float x = Math.max(m / 2.0f, 2);
+        g2d.setFont(font);
+        // 指定透明度
+        if (null != this.textAlpha) {
+            g2d.setComposite(this.textAlpha);
+        }
+        for (int i = 0; i < chars.length; i++) {
+            ac = AlphaComposite.getInstance(AlphaComposite.SRC_OVER, getPellucidity(chars.length, flag, i));
+            g2d.setComposite(ac);
+            g2d.setColor(fontColor[i]);
+            g2d.drawOval(num(width), num(height), num(5, 30), 5 + num(5, 30));//绘制椭圆边框
+            g2d.drawString(words[i] + "", x + (font.getSize() + m) * i, y);
+        }
+        g2d.dispose();
+        return image;
+    }
+
+    /**
+     * 获取透明度,从0到1,自动计算步长
+     *
+     * @return float 透明度
+     */
+    private float getPellucidity(int v, int i, int j) {
+        int num = i + j;
+        float r = (float) 1 / v;
+        float s = (v + 1) * r;
+        return num > v ? (num * r - s) : num * r;
+    }
+
+    /**
+     * 通过给定范围获得随机的颜色
+     *
+     * @return Color 获得随机的颜色
+     */
+    private Color getRandomColor(int min, int max) {
+        if (min > 255) {
+            min = 255;
+        }
+        if (max > 255) {
+            max = 255;
+        }
+        if (min < 0) {
+            min = 0;
+        }
+        if (max < 0) {
+            max = 0;
+        }
+        if (min > max) {
+            min = 0;
+            max = 255;
+        }
+        return new Color(min + num(max - min), min + num(max - min), min + num(max - min));
+    }
+
+
+    /**
+     * 产生两个数之间的随机数
+     *
+     * @param min 小数
+     * @param max 比min大的数
+     * @return int 随机数字
+     */
+    private int num(int min, int max) {
+        return min + RANDOM.nextInt(max - min);
+    }
+
+    /**
+     * 产生0--num的随机数,不包括num
+     *
+     * @param num 数字
+     * @return int 随机数字
+     */
+    private int num(int num) {
+        return RANDOM.nextInt(num);
+    }
+
+}

hutool-captcha/src/test/java/cn/hutool/captcha/CaptchaTest.java

@@ -1,11 +1,10 @@
 package cn.hutool.captcha;
 
-import org.junit.Assert;
-import org.junit.Ignore;
-import org.junit.Test;
-
 import cn.hutool.captcha.generator.MathGenerator;
 import cn.hutool.core.lang.Console;
+import org.junit.Assert;
+import org.junit.Ignore;
+import org.junit.Test;
 
 import java.awt.*;
 
@@ -13,7 +12,6 @@ import java.awt.*;
  * 直线干扰验证码单元测试
  *
  * @author looly
- *
  */
 public class CaptchaTest {
 
@@ -102,4 +100,12 @@ public class CaptchaTest {
         // 验证图形验证码的有效性，返回boolean值
         captcha.verify("1234");
     }
+
+    @Test
+    @Ignore
+    public void GifCaptchaTest() {
+        GifCaptcha captcha = CaptchaUtil.createGifCaptcha(200, 100, 4);
+        captcha.write("f:/gif_captcha.gif");
+        assert captcha.verify(captcha.getCode());
+    }
 }