Android给图片加文字和图片水印

前两天遇到这个功能需求，在网上查询到了一些资料，特意记录一下：给图片添加水印的基本思路都是载入原图，添加文字或者载入水印图片，保存图片这三个部分

添加水印图片1：

private Bitmap createWaterMaskImage(Context gContext, Bitmap src, Bitmap watermark)    {         String tag = "createBitmap";        Log.d(tag, "create a new bitmap");        if (src == null)        {            return null;        }               int w = src.getWidth();        int h = src.getHeight();        int ww = watermark.getWidth();        int wh = watermark.getHeight();        // create the new blank bitmap        Bitmap newb = Bitmap.createBitmap(w, h, Config.ARGB_8888);// 创建一个新的和SRC长度宽度一样的位图        Canvas cv = new Canvas(newb);        // draw src into        cv.drawBitmap(src, 0, 0, null);// 在 0，0坐标开始画入src        // draw watermark into        cv.drawBitmap(watermark, 20, 20, null);// 在src的右下角画入水印        // save all clip        cv.save(Canvas.ALL_SAVE_FLAG);// 保存        // store        cv.restore();// 存储        return newb;    }

添加水印图片2：

/**     * 设置水印图片在左上角     * @param Context     * @param src     * @param watermark     * @param paddingLeft     * @param paddingTop     * @return     */    public static Bitmap createWaterMaskLeftTop(            Context context, Bitmap src, Bitmap watermark,            int paddingLeft, int paddingTop) {        return createWaterMaskBitmap(src, watermark,                 dp2px(context, paddingLeft), dp2px(context, paddingTop));    }    private static Bitmap createWaterMaskBitmap(Bitmap src, Bitmap watermark,            int paddingLeft, int paddingTop) {        if (src == null) {            return null;        }        int width = src.getWidth();        int height = src.getHeight();        //创建一个bitmap        Bitmap newb = Bitmap.createBitmap(width, height, Config.ARGB_8888);// 创建一个新的和SRC长度宽度一样的位图        //将该图片作为画布        Canvas canvas = new Canvas(newb);        //在画布 0，0坐标上开始绘制原始图片        canvas.drawBitmap(src, 0, 0, null);        //在画布上绘制水印图片        canvas.drawBitmap(watermark, paddingLeft, paddingTop, null);        // 保存        canvas.save(Canvas.ALL_SAVE_FLAG);        // 存储        canvas.restore();        return newb;    }    /**     * 设置水印图片在右下角     * @param Context     * @param src     * @param watermark     * @param paddingRight     * @param paddingBottom     * @return     */    public static Bitmap createWaterMaskRightBottom(            Context context, Bitmap src, Bitmap watermark,            int paddingRight, int paddingBottom) {        return createWaterMaskBitmap(src, watermark,                 src.getWidth() - watermark.getWidth() - dp2px(context, paddingRight),                 src.getHeight() - watermark.getHeight() - dp2px(context, paddingBottom));    }    /**     * 设置水印图片到右上角     * @param Context     * @param src     * @param watermark     * @param paddingRight     * @param paddingTop     * @return     */    public static Bitmap createWaterMaskRightTop(            Context context, Bitmap src, Bitmap watermark,            int paddingRight, int paddingTop) {        return createWaterMaskBitmap( src, watermark,                 src.getWidth() - watermark.getWidth() - dp2px(context, paddingRight),                 dp2px(context, paddingTop));    }    /**     * 设置水印图片到左下角     * @param Context     * @param src     * @param watermark     * @param paddingLeft     * @param paddingBottom     * @return     */    public static Bitmap createWaterMaskLeftBottom(            Context context, Bitmap src, Bitmap watermark,            int paddingLeft, int paddingBottom) {        return createWaterMaskBitmap(src, watermark, dp2px(context, paddingLeft),                 src.getHeight() - watermark.getHeight() - dp2px(context, paddingBottom));    }    /**     * 设置水印图片到中间     * @param Context     * @param src     * @param watermark     * @return     */    public static Bitmap createWaterMaskCenter(Bitmap src, Bitmap watermark) {        return createWaterMaskBitmap(src, watermark,                 (src.getWidth() - watermark.getWidth()) / 2,                (src.getHeight() - watermark.getHeight()) / 2);    }

添加文字1：

public static Bitmap scaleWithWH(Bitmap src, double w, double h) {          if (w == 0 || h == 0 || src == null) {              return src;          } else {              // 记录src的宽高              int width = src.getWidth();              int height = src.getHeight();              // 创建一个matrix容器              Matrix matrix = new Matrix();              // 计算缩放比例              float scaleWidth = (float) (w / width);              float scaleHeight = (float) (h / height);              // 开始缩放              matrix.postScale(scaleWidth, scaleHeight);              // 创建缩放后的图片              return Bitmap.createBitmap(src, 0, 0, width, height, matrix, true);          }      }     public Bitmap drawTextToBitmap(Context gContext,               int gResId,               String gText) {              Resources resources = gContext.getResources();              float scale = resources.getDisplayMetrics().density;              Bitmap bitmap =                   BitmapFactory.decodeResource(resources, gResId);                            bitmap = scaleWithWH(bitmap, 300*scale, 300*scale);                         android.graphics.Bitmap.Config bitmapConfig =                  bitmap.getConfig();                                                     // set default bitmap config if none              if(bitmapConfig == null) {                bitmapConfig = android.graphics.Bitmap.Config.ARGB_8888;              }              // resource bitmaps are imutable,               // so we need to convert it to mutable one              bitmap = bitmap.copy(bitmapConfig, true);                            Canvas canvas = new Canvas(bitmap);              // new antialised Paint              Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);              // text color - #3D3D3D              paint.setColor(Color.RED);                paint.setTextSize((int) (18 * scale));                           paint.setDither(true); //获取跟清晰的图像采样               paint.setFilterBitmap(true);//过滤一些              Rect bounds = new Rect();              paint.getTextBounds(gText, 0, gText.length(), bounds);                          int x = 30;              int y = 30;                          canvas.drawText(gText, x * scale, y * scale, paint);                             return bitmap;            }

添加文字2：

/**     * 给图片添加文字到左上角     * @param context     * @param bitmap     * @param text     * @return     */    public static Bitmap drawTextToLeftTop(Context context, Bitmap bitmap, String text,            int size, int color, int paddingLeft, int paddingTop) {        Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);        paint.setColor(color);        paint.setTextSize(dp2px(context, size));        Rect bounds = new Rect();        paint.getTextBounds(text, 0, text.length(), bounds);        return drawTextToBitmap(context, bitmap, text, paint, bounds,                 dp2px(context, paddingLeft),                  dp2px(context, paddingTop) + bounds.height());    }    /**     * 绘制文字到右下角     * @param context     * @param bitmap     * @param text     * @param size     * @param color     * @param paddingLeft     * @param paddingTop     * @return     */    public static Bitmap drawTextToRightBottom(Context context, Bitmap bitmap, String text,            int size, int color, int paddingRight, int paddingBottom) {        Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);        paint.setColor(color);        paint.setTextSize(dp2px(context, size));        Rect bounds = new Rect();        paint.getTextBounds(text, 0, text.length(), bounds);        return drawTextToBitmap(context, bitmap, text, paint, bounds,                 bitmap.getWidth() - bounds.width() - dp2px(context, paddingRight),                 bitmap.getHeight() - dp2px(context, paddingBottom));    }    /**     * 绘制文字到右上方     * @param context     * @param bitmap     * @param text     * @param size     * @param color     * @param paddingRight     * @param paddingTop     * @return     */    public static Bitmap drawTextToRightTop(Context context, Bitmap bitmap, String text,            int size, int color, int paddingRight, int paddingTop) {        Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);        paint.setColor(color);        paint.setTextSize(dp2px(context, size));        Rect bounds = new Rect();        paint.getTextBounds(text, 0, text.length(), bounds);        return drawTextToBitmap(context, bitmap, text, paint, bounds,                 bitmap.getWidth() - bounds.width() - dp2px(context, paddingRight),                 dp2px(context, paddingTop) + bounds.height());    }    /**     * 绘制文字到左下方     * @param context     * @param bitmap     * @param text     * @param size     * @param color     * @param paddingLeft     * @param paddingBottom     * @return     */    public static Bitmap drawTextToLeftBottom(Context context, Bitmap bitmap, String text,            int size, int color, int paddingLeft, int paddingBottom) {        Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);        paint.setColor(color);        paint.setTextSize(dp2px(context, size));        Rect bounds = new Rect();        paint.getTextBounds(text, 0, text.length(), bounds);        return drawTextToBitmap(context, bitmap, text, paint, bounds,                 dp2px(context, paddingLeft),                  bitmap.getHeight() - dp2px(context, paddingBottom));    }    /**     * 绘制文字到中间     * @param context     * @param bitmap     * @param text     * @param size     * @param color     * @return     */    public static Bitmap drawTextToCenter(Context context, Bitmap bitmap, String text,            int size, int color) {        Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);        paint.setColor(color);        paint.setTextSize(dp2px(context, size));        Rect bounds = new Rect();        paint.getTextBounds(text, 0, text.length(), bounds);        return drawTextToBitmap(context, bitmap, text, paint, bounds,                 (bitmap.getWidth() - bounds.width()) / 2,                  (bitmap.getHeight() + bounds.height()) / 2);    }    //图片上绘制文字    private static Bitmap drawTextToBitmap(Context context, Bitmap bitmap, String text,            Paint paint, Rect bounds, int paddingLeft, int paddingTop) {        android.graphics.Bitmap.Config bitmapConfig = bitmap.getConfig();        paint.setDither(true); // 获取跟清晰的图像采样        paint.setFilterBitmap(true);// 过滤一些        if (bitmapConfig == null) {            bitmapConfig = android.graphics.Bitmap.Config.ARGB_8888;        }        bitmap = bitmap.copy(bitmapConfig, true);        Canvas canvas = new Canvas(bitmap);        canvas.drawText(text, paddingLeft, paddingTop, paint);        return bitmap;    }    /**     * 缩放图片     * @param src     * @param w     * @param h     * @return     */    public static Bitmap scaleWithWH(Bitmap src, double w, double h) {        if (w == 0 || h == 0 || src == null) {            return src;        } else {            // 记录src的宽高            int width = src.getWidth();            int height = src.getHeight();            // 创建一个matrix容器            Matrix matrix = new Matrix();            // 计算缩放比例            float scaleWidth = (float) (w / width);            float scaleHeight = (float) (h / height);            // 开始缩放            matrix.postScale(scaleWidth, scaleHeight);            // 创建缩放后的图片            return Bitmap.createBitmap(src, 0, 0, width, height, matrix, true);        }    }    /**     * dip转pix     * @param context     * @param dp     * @return     */    public static int dp2px(Context context, float dp) {         final float scale = context.getResources().getDisplayMetrics().density;         return (int) (dp * scale + 0.5f);     }