I am using Camera api to capture ID cards pictures, I have an over lay as shown in the image bellow. I want to crop the image in the box. could you suggest on how exactly it should be done. I have written down what I have tried and the results it gives me.
This is the screenshot of the id i want to capture..
Output.
white rectangular box is a photo frame which is right in the centre in a Relative layout
<View
android:id="#+id/photo_frame"
android:layout_width="match_parent"
android:layout_height="212dp"
android:background="#drawable/bg_photo_frame"
android:layout_centerInParent="true"
android:layout_margin="#dimen/double_padding"
android:visibility="visible"/>
How do I calculate this frame to cut the image
this is what I have to cut the image which needs modification but not sure what is the way forward
public Bitmap cutImage(final Bitmap srcBmp, final int pixepWidth, final int pixelsHeight, float widthRatio) {
// Bitmap croppedBitmap = Bitmap.createBitmap(bitmap, 20, 20, pixepWidth, pixelsHeight);
// return croppedBitmap;
Bitmap dstBmp;
if (srcBmp.getWidth() >= srcBmp.getHeight()){
dstBmp = Bitmap.createBitmap(
srcBmp,
srcBmp.getWidth()/2 - srcBmp.getHeight()/2,
0,
srcBmp.getHeight(),
srcBmp.getHeight()
);
}else{
dstBmp = Bitmap.createBitmap(
srcBmp,
0,
srcBmp.getHeight()/2 - srcBmp.getWidth()/2,
srcBmp.getWidth(),
srcBmp.getWidth()
);
}
return dstBmp;
}
Resizing view using onTouchListener
You apply some kind of touchListener to the overlay view for resizing and moving the overlay. ImageButton seems to work, so I use ImageButton with a frame.xml to draw a border.
Then you apply the global coordinates of the overlay (x, y, width, height) against the coordinates of the bitmap (x, y, width, height).
The overlay x and the overlay y can’t be less than 0, and the overlay x + the overlay width cannot be greater than the bitmap width.
To perform the crop, use Bitmap.createBitmap():
Bitmap.createBitmap(Bitmap source, int x, int y, int width, int height)
How to crop Bitmap?
While searching for results I came across this
How can I convert a View to a Drawable?
The idea behind this is I can convert TextView into a bitmap first and then combine the two bitmaps. But by converting the TextView into Bitmap, it would make it lose it's transparency which I don't want. I want the TextView over my ImageView but as one image using canvas.
My idea is to create images like these:
Here I want to enclose the text with a drawable shape for that white border.
And then place this Textview on an image and then save everything as a bitmap.
Please help
You can try to draw text and lines on canvas.
Below is example method which draws text on drawable image and returns Bitmap.
You can set custom font by calling .setTypeface() on Paint object.
Call canvas.drawLine() to draw line. To customize your line you can create new Paint object, set its color and width by .setColor() and .setStrokeWidth() and pass it in drawLine() together with line coordinates.
public Bitmap drawTextOnBitmap(Context context, int resId, String text) {
// prepare canvas
Resources resources = context.getResources();
float scale = resources.getDisplayMetrics().density;
Bitmap bitmap = BitmapFactory.decodeResource(resources, resId);
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 immutable, so we need to convert it to mutable one
bitmap = bitmap.copy(bitmapConfig, true);
Canvas canvas = new Canvas(bitmap);
// new antialiased Paint
TextPaint paint = new TextPaint(Paint.ANTI_ALIAS_FLAG);
// text color - #3D3D3D
paint.setColor(Color.rgb(61, 61, 61));
// text size in pixels
paint.setTextSize((int) (bitmap.getHeight() / 10 * scale));
// text shadow
paint.setShadowLayer(1f, 0f, 1f, Color.WHITE);
// set text width to canvas width minus 16dp padding
int textWidth = canvas.getWidth() - (int) (16 * scale);
// init StaticLayout for text
StaticLayout textLayout = new StaticLayout(text, paint, textWidth,
Layout.Alignment.ALIGN_CENTER, 1.0f, 0.0f, false);
// get height of multiline text
int textHeight = textLayout.getHeight();
// get position of text's top left corner
float x = (bitmap.getWidth() - textWidth) / 2;
float y = (bitmap.getHeight() - textHeight) / 2;
// draw text to the Canvas center
canvas.save();
canvas.translate(x, y);
textLayout.draw(canvas);
canvas.restore();
return bitmap;
}
Update:
To draw rectangle add this to the method:
Paint p = new Paint();
p.setStyle(Paint.Style.STROKE);
p.setStrokeWidth(24);
RectF rectF = new RectF(80, 150, 200, 350);
canvas.drawRect(rectF, p);
Parameters for new RectF():
left
The X coordinate of the left side of the rectangle
top
The Y coordinate of the top of the rectangle
right
The X coordinate of the right side of the rectangle
bottom
The Y coordinate of the bottom of the rectangle
I am creating a Marker with text but the text is showing only 3 characters and very small and it is right of the bit map image. I want the text to go across the middle of the icon and it big font. I manually increased setFontsize to larger size did not work and also drawText width and height still did not work.
private Drawable createMarkerIcon(Drawable backgroundImage, String text,
int width, int height) {
Bitmap canvasBitmap = Bitmap.createBitmap(width, height,
Bitmap.Config.ARGB_8888); //width, height,
// Create a canvas, that will draw on to canvasBitmap.
Canvas imageCanvas = new Canvas(canvasBitmap);
// Set up the paint for use with our Canvas
Paint imagePaint = new Paint();
imagePaint.setTextAlign(Align.CENTER);
imagePaint.setTextSize(26f); // 8f
// Draw the image to our canvas
backgroundImage.draw(imageCanvas);
// Draw the text on top of our image
imageCanvas.drawText(text, width /1, height / 1, imagePaint); //2 , 2
// Combine background and text to a LayerDrawable
LayerDrawable layerDrawable = new LayerDrawable(
new Drawable[]{backgroundImage, new BitmapDrawable(canvasBitmap)});
return layerDrawable;
}
I call this function:
d=createMarkerIcon(getResources().getDrawable(R.drawable.pointer_bubble_selected), markerTxt, 100, 100); //marker_green=23x37 29, 50
Here is the solution for the text overlay bound problem. Replace one line with all this lines:
// draw text to the Canvas center
Rect bounds = new Rect();
int x = (canvasBitmap.getWidth() - bounds.width())/2;
int y = (canvasBitmap.getHeight() + bounds.height())/2;
// Draw the text on top of our image
//imageCanvas.drawText(text, width /4, height / 4, imagePaint); //OLD
imageCanvas.drawText(text, x , y, imagePaint); //NEW
I have a drawable resource that I need to draw on a canvas. I need to have the drawable centered at point (x,y). Right now if I do canvas.drawBitmap(mBitmap, x, y, mPaint), (x,y) represent (left,top). Does anyone know how I may get the center of my drawable so I can place it on the canvas correctly?
Get the width and height of the canvas.
Now, you need to draw it on width/2 and height/2.
To be more centered, you can subtract from width/2 half of the bitmap width, and from height/2 half of the bitmap height.
canvas.drawBitmap(mBitmap, width/2-mBitmap.getWidth()/2, height/2-mBitmap.getHeight()/2, mPaint);
A Simple math...
int centerX = drawable.getIntrinsicWidth() / 2;
int centerY = drawable.getIntrinsicHeight() / 2;
For example I want a white border of 10pixel around all 4 side of the bitmap. I am not using it for imageview
I am currently using this code to crop image. May I know how I could add a white border into it?
public Bitmap scaleCenterCrop(Bitmap source, int newHeight, int newWidth) {
int sourceWidth = source.getWidth();
int sourceHeight = source.getHeight();
// Compute the scaling factors to fit the new height and width, respectively.
// To cover the final image, the final scaling will be the bigger
// of these two.
float xScale = (float) newWidth / sourceWidth;
float yScale = (float) newHeight / sourceHeight;
float scale = Math.max(xScale, yScale);
// Now get the size of the source bitmap when scaled
float scaledWidth = scale * sourceWidth;
float scaledHeight = scale * sourceHeight;
// Let's find out the upper left coordinates if the scaled bitmap
// should be centered in the new size give by the parameters
float left = (newWidth - scaledWidth) / 2;
float top = (newHeight - scaledHeight) / 2;
// The target rectangle for the new, scaled version of the source bitmap will now
// be
RectF targetRect = new RectF(left, top, left + scaledWidth, top + scaledHeight);
// Finally, we create a new bitmap of the specified size and draw our new,
// scaled bitmap onto it.
Bitmap dest = Bitmap.createBitmap(newWidth, newHeight, source.getConfig());
Canvas canvas = new Canvas(dest);
canvas.drawBitmap(source, null, targetRect, null);
return dest;
}
I wrote a function for this:
private Bitmap addWhiteBorder(Bitmap bmp, int borderSize) {
Bitmap bmpWithBorder = Bitmap.createBitmap(bmp.getWidth() + borderSize * 2, bmp.getHeight() + borderSize * 2, bmp.getConfig());
Canvas canvas = new Canvas(bmpWithBorder);
canvas.drawColor(Color.WHITE);
canvas.drawBitmap(bmp, borderSize, borderSize, null);
return bmpWithBorder;
}
Basically it creates a new Bitmap adding 2 * bordersize to each dimension and then paints the original Bitmap over it, offsetting it with bordersize.
As for a way of doing this. You make your bitmap bigger than the one your adding to it and then fill the canvas with the background you want. If you need to add other effects you can look into the canvas options for clipping the rect and adding rounded corners and such.
RectF targetRect = new RectF(left+10, top+10, left + scaledWidth, top + scaledHeight);
Bitmap dest = Bitmap.createBitmap(newWidth+20, newHeight+20, source.getConfig());
Canvas canvas = new Canvas(dest);
canvas.drawColor(Color.WHITE);
canvas.drawBitmap(source, null, targetRect, null);
You can draw 4 rectangles after painting your bitmap's stuff.
point 0,0,3,sizey
point 0,0,sizex,3
point 0,sizey-3,sizex,sizey
point sizex-3,0,sizex,sizey
the accepted answer is nice but in the cases that bitmap contains a transparent background, it fills all over the background of source bitmap with white pixels. so it doesn't work fine for all cases.
a better way to achieve this goal is using Canvas#drawLine method like the following code:
Bitmap drawBorder(Bitmap source) {
int width = source.getWidth();
int height = source.getHeight();
Bitmap bitmap = Bitmap.createBitmap(width, height, source.getConfig());
Canvas canvas = new Canvas(bitmap);
Paint paint = new Paint();
paint.setStrokeWidth(50);
paint.setColor(Color.WHITE);
canvas.drawLine(0, 0, width, 0, paint);
canvas.drawLine(width, 0, width, height, paint);
canvas.drawLine(width, height, 0, height, paint);
canvas.drawLine(0, height, 0, 0, paint);
canvas.drawBitmap(source, 0, 0, null);
return bitmap;
}
in this way we first create a second bitmap using source bitmap width, height and config and use drawline() mathod four times to draw four lines using coordinates of end points of each line around the second bitmap and then draw the source bitmap on the second bitmap that must be returned.
A super easy way of doing it would be to set the ImageView background to white and add a padding value.
If that doesn't work, create a FrameLayout with w/h of wrap_content, set its background to white, put the ImageView in there, and set the ImageView's margins to the desired border width.
Its not elegant but you can always just draw a rectangle behind it, you already have the code to do this and any performance impact is going to be unnoticeable
You can create your targetRectangle 20px wider and 20px higher
RectF targetRect = new RectF(left, top, left + scaledWidth + 20, top + scaledHeight + 20);
and paint the background white
Try this it will also add border to your canvas
canvas.drawLine(0, 0, canvas.getWidth(), 0, paint2);
canvas.drawLine(0, 0, 0, canvas.getHeight(), paint2);
canvas.drawLine(0, canvas.getHeight(), canvas.getWidth(),
canvas.getHeight(), paint2);
canvas.drawLine(canvas.getWidth(), 0, canvas.getWidth(),
canvas.getHeight(), paint2);