Android to the picture plus text and image watermarking example code

When we are doing the project sometimes need to add a watermark to the picture, Shuizhong today encountered such a problem, so engage in a tool category, posted directly call you on the line.

/**
 *  Picture tool class 
 * @author  Cold water 
 *
 */
public class ImageUtil {

  /**
   *  Set watermark image in the upper left corner 
   * @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();
    // Create a bitmap
    Bitmap newb = Bitmap.createBitmap(width, height, Config.ARGB_8888);//  Create a new and SRC A bitmap of the same length and width 
    // Use this picture as a canvas 
    Canvas canvas = new Canvas(newb);
    // On canvas  0，0 Start drawing the original picture on the coordinates 
    canvas.drawBitmap(src, 0, 0, null);
    // Draw watermark pictures on canvas 
    canvas.drawBitmap(watermark, paddingLeft, paddingTop, null);
    //  Preservation 
    canvas.save(Canvas.ALL_SAVE_FLAG);
    //  storage 
    canvas.restore();
    return newb;
  }

  /**
   *  Set watermark image in the bottom right corner 
   * @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));
  }

  /**
   *  Set watermark image to the upper right corner 
   * @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));
  }

  /**
   *  Set watermark image to the lower left corner 
   * @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));
  }

  /**
   *  Set watermark pictures to the center 
   * @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);
  }

  /**
   *  Add text to the top left corner of the picture 
   * @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());
  }

  /**
   *  Draw text to the lower right corner 
   * @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));
  }

  /**
   *  Draw text to the upper right 
   * @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());
  }

  /**
   *  Draw text to the bottom left 
   * @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));
  }

  /**
   *  Draw text to the middle 
   * @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);
  }

  // Draw text on the picture 
  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); //  Get samples with clear images 
    paint.setFilterBitmap(true);//  Filter some 
    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;
  }

  /**
   *  Zoom pictures 
   * @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 {
      //  Record src Width of height 
      int width = src.getWidth();
      int height = src.getHeight();
      //  Create a matrix container 
      Matrix matrix = new Matrix();
      //  Calculate scaling 
      float scaleWidth = (float) (w / width);
      float scaleHeight = (float) (h / height);
      //  Zoom start 
      matrix.postScale(scaleWidth, scaleHeight);
      //  Create a zoomed picture 
      return Bitmap.createBitmap(src, 0, 0, width, height, matrix, true);
    }
  }

  /**
   * dip turn 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); 
  } 
}

Use as follows:

Add a layout, the above is the original picture, the following is to add the watermark after the picture

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:tools="http://schemas.android.com/tools"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:orientation="vertical">

  <TextView
    android:id="@+id/sour_pic_title"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text=" Original " />

  <ImageView 
    android:id="@+id/sour_pic"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:scaleType="centerInside"/>

  <TextView
    android:id="@+id/watermark_pic_title"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text=" watermark " />

  <ImageView 
    android:id="@+id/wartermark_pic"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:scaleType="centerInside"/>

</LinearLayout>

In the Activity to get to the ImageView object, and get Bitmap object, the Bitmap canva drawing, add watermark:

/**
 *  Picture tool class 
 * @author  Cold water 
 *
 */
public class MainActivity extends Activity {

  private ImageView mSourImage;
  private ImageView mWartermarkImage;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    initView();
  }

  private void initView(){
    mSourImage = (ImageView) findViewById(R.id.sour_pic);
    mWartermarkImage = (ImageView) findViewById(R.id.wartermark_pic);
    Bitmap sourBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.sour_pic);
    mSourImage.setImageBitmap(sourBitmap);

    Bitmap waterBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.weixin);

    Bitmap watermarkBitmap = ImageUtil.createWaterMaskCenter(sourBitmap, waterBitmap);
    watermarkBitmap = ImageUtil.createWaterMaskLeftBottom(this, watermarkBitmap, waterBitmap, 0, 0);
    watermarkBitmap = ImageUtil.createWaterMaskRightBottom(this, watermarkBitmap, waterBitmap, 0, 0);
    watermarkBitmap = ImageUtil.createWaterMaskLeftTop(this, watermarkBitmap, waterBitmap, 0, 0);
    watermarkBitmap = ImageUtil.createWaterMaskRightTop(this, watermarkBitmap, waterBitmap, 0, 0);

    Bitmap textBitmap = ImageUtil.drawTextToLeftTop(this, watermarkBitmap, " Top left corner ", 16, Color.RED, 0, 0);
    textBitmap = ImageUtil.drawTextToRightBottom(this, textBitmap, " Bottom right corner ", 16, Color.RED, 0, 0);
    textBitmap = ImageUtil.drawTextToRightTop(this, textBitmap, " Top right corner ", 16, Color.RED, 0, 0);
    textBitmap = ImageUtil.drawTextToLeftBottom(this, textBitmap, " Lower left quarter ", 16, Color.RED, 0, 0);
    textBitmap = ImageUtil.drawTextToCenter(this, textBitmap, " Middle ", 16, Color.RED);

    mWartermarkImage.setImageBitmap(textBitmap);
  }
}

The above is the full content of this article, we hope to learn all the help, but also hope that we support a lot of script home.

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Android to the picture plus text and image watermarking example code - CodeDay