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How should I add a watermark effect to an image in Android? [duplicate]

This question already has answers here:
How to draw text On image?
(7 answers)
Closed 2 years ago.
I am new for android and i want to add watermark effect on captured images and i am trying find the solution for it since 2 days but still not able to add watermark effect on captured images can some one help me what i did mistack in my below code..
I want add water mark effect on bottom middle of image
Code
private void onCaptureImageResult(Intent data) {
Bitmap photo;Bitmap watermark_bitmap=null;
String selectedFilePath = null;
if (data.getExtras().get("data") != null) {
photo = (Bitmap) data.getExtras().get("data");
watermark_bitmap=Utilities.mark(this,photo,"Hello World",true);
Uri contentUri = Utilities.getImageUri1(
this, watermark_bitmap);
selectedFilePath = ImageFilePath.getPath(
this, contentUri);
newMeter_image.setImageBitmap(watermark_bitmap);
}
public static Bitmap mark(Context context,Bitmap src, String watermark, boolean underline) {
int w = src.getWidth();
int h = src.getHeight();
Bitmap result = Bitmap.createBitmap(w, h, src.getConfig());
Canvas canvas = new Canvas(result);
canvas.drawBitmap(src, 0, 0, null);
Paint paint = new Paint();
int color = ContextCompat.getColor(context, R.color.black);
paint.setColor(color);
paint.setAlpha(1);
paint.setTextSize(5);
paint.setAntiAlias(true);
paint.setUnderlineText(underline);
canvas.drawText(watermark, 50,50, paint);
return result;
}

I would have also used the same approach.
Load the image in a canvas.
Canvas canvas = new Canvas(result);
canvas.drawBitmap(src, 0, 0, null);
Set the paint and draw the text/drawable/bitmap of your watermark at the location you desire.
Instead of using hardcoded values (50,50) try using calculated values.
canvas.drawText("Watermark",canvas.width/2, canvas.height/2, paint)
This will make the watermark as a part of your image.
If you want to keep it separate but create an illusion of watermark, then you can display your watermark as src in an imageView and overlay it over your actual image display view.
Sorry if I misunderstood. Do share a better solution though!

Android Drawing text onto a bitmap

I'm trying to write some text across a bitmap in Android. I've followed several guides and attempted several different code variations but I either get something obscure, a blank screen or the unaltered bitmap. This is the basic idea of what I've been playing around with.
public Bitmap writeOnDrawable(Context gContext, String path, String text) {
Bitmap bitmap = BitmapFactory.decodeFile(path);
Bitmap bmOverlay = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Bitmap.Config.ARGB_4444);
Canvas canvas = new Canvas(bmOverlay);
Paint paint = new Paint();
paint.setColor(Color.CYAN);
paint.setTextSize(20);
paint.setFlags(Paint.ANTI_ALIAS_FLAG);
canvas.drawBitmap(bitmap, 0, 0, null);
canvas.drawPoint(30, 50, paint);
canvas.drawText("Text", 33, 53, paint);
return bmOverlay;
}
I pass this function the variables and then use the returned bitmap by turning it into a BitmapDrawable and making it a background of a layout. This particular version of the function returns only my initial, unaltered bitmap with no "Text" text across it.
I've attempted variations such as copying the original image:
Bitmap drawableBitmap = bitmap.copy(Bitmap.Config.ARGB_8888, true);
Drawing the original image onto the canvas:
canvas.drawBitmap(drawableBitmap, screenHeight, screenWidth, paint);

I solved the problem using android-maps-util library.
add compile 'com.google.maps.android:android-maps-utils:0.4' dependency to your gradle file.
Use IconGenerator to create bitmap with text and use it in your BitmapDescriptor to create marker on your map.

Water reflection effect on bitmap

I trying to achieve water reflection effect on bitmap. As I saw some apps called water reflection. I know how to do the reflection of the image but the wave on the image is what making me confused on how it is done.
see this image for example
I did many apps on bitmap manipulation but this is quite hard to achieve.
So any idea on where to start. Just an idea to start can be helpful.

For any one needed, I tried some simple tricks to get as closer as water reflection effect. It is not great but it looks fine to me.
I used two methods
Bitmap reflection method (give bitmap as a parameter)
public static Bitmap Reflection(Bitmap imageBitmap) {
int width = imageBitmap.getWidth();
int height = imageBitmap.getHeight();
Matrix matrix = new Matrix();
matrix.preScale(1, -1);
Bitmap reflectionImage = Bitmap.createBitmap(imageBitmap, 0,
0, width, height , matrix, false);
Bitmap newbit=Bitmap.createScaledBitmap(reflectionImage, reflectionImage.getWidth()/8, reflectionImage.getHeight()/8, true);
Bitmap newbit1=Bitmap.createScaledBitmap(newbit, newbit.getWidth()*8, newbit.getHeight()*8, true);
Bitmap scalednew=Bitmap.createScaledBitmap(newbit1, width, height-(height/4), true);
Bitmap newscaledone=overlay(scalednew);
reflectionImage=newscaledone;
Bitmap reflectedBitmap = Bitmap.createBitmap(width,
(height + height), Config.ARGB_8888);
Canvas canvas = new Canvas(reflectedBitmap);
canvas.drawBitmap(imageBitmap, 0, 0, null);
Paint defaultPaint = new Paint();
canvas.drawRect(0, height, width, height, defaultPaint);
canvas.drawBitmap(reflectionImage, 0, height , null);
Paint paint = new Paint();
paint.setXfermode(new PorterDuffXfermode(Mode.DST_IN));
canvas.drawRect(0, height, width, reflectedBitmap.getHeight()
, paint);
return reflectedBitmap;
}
Bitmap overlay method. I am taking a wave bitmap with some opacity to overlay on the reflected image. So that it may look like water.
Bitmap wavebitmap=BitmapFactory.decodeResource(getResources(), R.drawable.waves1);
private static Bitmap overlay( Bitmap bmp2) {
Bitmap bmp1=WaterReflectionMainActivity.wavebitmap;
Bitmap bmp1new =Bitmap.createScaledBitmap(bmp1, bmp2.getWidth(), bmp2.getHeight(), true);
Bitmap bmOverlay = Bitmap.createBitmap(bmp1new.getWidth(), bmp1new.getHeight(), bmp1new.getConfig());
Canvas canvas = new Canvas(bmOverlay);
canvas.drawBitmap(bmp2, new Matrix(), null);
canvas.drawBitmap(bmp1new, new Matrix(), null);
return bmOverlay;
}
Well this is my version of water effect, I know this looks shit.
So if anyone still got some better effect please share your code .
thank you

Tutorial related to this: http://www.xaraxone.com/webxealot/workbook34/page_4.htm
Also have a read at this question: Add water effect on bitmap android.
Have a read at both of them, i hope you will get an idea from this
You may also want to look through these: 1, 2, 3

This is just an idea but basically, what you need is to apply a deformation on the bottom part of the image, meaning that for each pixel on the bottom half, you compute a position to get it's color from the top picture.
Here's a pseudo code to give you a hint :
for (int x = 0; x < width; x++) {
for (int y = 0; y < img.height; y++) {
// Compute a position on the original image
// tweak the values heres to get the effect you want
sourceX = x + (int) (cos(10000.0 / y) * 20);
sourceY = img.height - y - 1 +(int)( sin(y* 0.5) * 20);
// Maybe check the range of sourceX and source Y
int color = img.getColor(sourceX, sourceY)
outptut.setColor(x, y + img.height, color);
}
}

you can achieve this by masking may this code will help you
http://www.seeques.com/22527681/how-can-do-this-effect-in-android-may-be-android-bitmap-masking-effect.html
EDIT
also see this for reference
http://code.google.com/p/android-ripple-demo/source/browse/#svn%2Ftrunk%2Fsrc%2Fcom%2Fkesalin%2FRippleDemo
https://github.com/esteewhy/whater
http://code.google.com/p/waterrippleeffect/source/browse/trunk/src/com/example/android/watereffect/WaterEffectView.java?r=3
android noise effect on bitmap

Show portion of Bitmap image on canvas in Android

I am trying to build a Magnify tool in my Android app. For this, I have an ImageView, which I converted to Bitmap (with some zoom/scale factor).
imageView.setDrawingCacheEnabled(true);
Bitmap drawingCache = imageView.getDrawingCache(true);
Matrix matrix = new Matrix();
matrix.postScale(5, 5);
Bitmap viewCapture = Bitmap.createBitmap(drawingCache, 0, 0,
drawingCache.getWidth(),
drawingCache.getHeight(),
matrix, true);
imageView.setDrawingCacheEnabled(false);
Now, I am drawing this Bitmap image "viewCapture" to my canvas. Here, I want only portion of the image to be rendered on the canvas.
I tried using approaches: "setRectToRect() on Matrix", "canvas.drawBitmap(bitmap, src, dst, paint)". But, didn't work out appropriately.
Would using SurfaceViews be helpful? Has anyone come across this situation? Please post your thoughts/ideas.

Why not just use the following?
Canvas.drawBitmap(Bitmap bitmap, Rect src, RectF dst, Paint paint)
src corresponds to which region of the bitmap you want to draw and dst says where you want the bitmap drawn. You can read more about it here: http://developer.android.com/reference/android/graphics/Canvas.html

When I do that, I get a smaller image of the bitmap, instead of cropped image. Following is the snippet I have used.
Canvas c = holder.lockCanvas();
c.drawRGB(10, 10, 10);
Rect src = new Rect((int)x - _image.getWidth(), (int) y - _image.getHeight(), (int)x + _image.getWidth(), (int) y + _image.getHeight());
RectF dst = new RectF((int)x - 50, (int) y - 50, (int)x + 50, (int) y + 50);
c.drawBitmap(_image, src, dst, null);
holder.unlockCanvasAndPost(c);

draw circle on bitmap

i've written an app that captures a picture and saves it on the sdcard. i then can load that image into an imageview to display it. i'd like to draw a circle on the bitmap before i display it. the code below displays the bitmap but no circle, any ideas why the circle is not there?
thanks.
BitmapFactory.Options bfo = new BitmapFactory.Options();
bfo.inSampleSize = 5;
Bitmap bm = BitmapFactory.decodeByteArray(imageArray, 0, imageArray.length, bfo);
Log.e(TAG, bm.toString());
//imageview.setImageBitmap(bm);
Bitmap bmOverlay = Bitmap.createBitmap(bm.getWidth(), bm.getHeight(), bm.getConfig());
canvas = new Canvas(bmOverlay);
Paint paint = new Paint();
paint.setColor(Color.RED);
canvas.drawBitmap(bm, new Matrix(), null);
canvas.drawCircle(750, 14, 11, paint);
imageview.setImageBitmap(bmOverlay);

You might check bm.getWidth. If you are using a sample size of 5 then your image will be 5 times smaller than the original, causing your circle to disappear off the right side of the image.
You could try:
paint.setStrokeWidth(10);
canvas.drawCircle(50, 50, 25);
just as a sanity check.