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How to crop resize image in Java?

When I set the image with actual size onto a panel and cropping using mouse it's working fine but when I resize image onto panel and cropping it's getting wrong cropping image. How to crop resize image using mouse?
int x = Math.min(p1.x, p2.x);
int y = Math.min(p1.y, p2.y);
int w = Math.abs(p1.x - p2.x);
int h = Math.abs(p1.y - p2.y);
BufferedImage dest = image.getSubimage(x,y,w,h)

If you want to crop from the original image then you will need to calculate the x/y scale factors of the two images. Then you will need to adjust the x/y/width/height values by these scale factors.
So if your original image is 400 x 100 and the resized image is 100 x 100 you would do something like:
double xScale = originalImageWidth / resizeImageWidth = 400 / 100 = 4.
So now if the cropping rectangle on the resized image is (10, 10, 20, 30);
Then you need to calculate your values something like:
int x = rectangle.x * xScale;
int width = rectangle.width * xScale;
image.getSubImage(x, y, width, height);
You would obviously need to calculate the y / height values using the y scaling factor.

Scaling down and making image square in android

I need a way to scale an image down to 78x78. I have found ways of doing this by cutting part of the image off, like this:
Bitmap image = Bitmap.createBitmap(image, 0, 0, 78, 78);
but I need to maintain as much of the image as possible. I had thought of scaling the image down and then making it square:
Bitmap image = Bitmap.createScaledBitmap(imageTest, 78, 78, true);
but of course this creates a square image that is squashed.
Can anyone suggest how I can create a 78x78 image that doesn't rescale and maintains as much of the original image as possible?

From what I understood, you should scale down and center crop the image. Try this code out.
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;
}
Hope it helps

Try this:
Bitmap image = Bitmap.createScaledBitmap(testImage, (int) 78 * (testImage.getWidth() / testImage.getHeight()), 78, true);
image = Bitmap.createBitmap(image, (int) (image.getWidth() - 78) / 2, 78);
Haven't tested this, as I'm on my way to bed, but it should accomplish what you want, so long as your image has a width greater than or equal to its height.
Regardless, I'd suggest you use BufferedImage instead of Bitmap.

The idea here would be resize your image using the same resize rate for width and height keeping the smaller size in 78. After that you can use a center point based crop to get the middle of your image and making it a squared image.
Image srcImage;
int widthSrc = 150;
int heightSrc = 180;
float resizeRate = 78 / min(widthSrc, heightSrc);
Image resizedImage = resizeImage($srcImage, resizeRate);
int widthDest = 78;
int heightDest = 78;
int cropX = ($widthSrc - $widthDest)/2;
int cropY = ($heightSrc - $heightDest)/2;
Image croppedImage = cropImage(resizedImage,$widthDest, $heightDest, $cropX, $cropY);
If the image is already square you can skip the crop part.

Android - Draw Bitmap within Canvas

I currently have a maze game which draws a 5 x 5 square (takes the width of screen and splits it evenly). Then for each of these boxes using x and y cordinates I user drawRect, to draw a colored background.
The issue I am having is I now need to draw an image within this same location, therefore replacing the current plain background colour fill.
Here is the code I am currently using to drawRect (a few example):
// these are all the variation of drawRect that I use
canvas.drawRect(x, y, (x + totalCellWidth), (y + totalCellHeight), green);
canvas.drawRect(x + 1, y, (x + totalCellWidth), (y + totalCellHeight), green);
canvas.drawRect(x, y + 1, (x + totalCellWidth), (y + totalCellHeight), green);
I would then also need to implement a background image for all the other squares within my canvas. This background will have simple 1px black lines drawn over the top of it, current code to draw in a grey background.
background = new Paint();
background.setColor(bgColor);
canvas.drawRect(0, 0, width, height, background);
Could you please advice if this is at all possible. If so, what is the best way I can go about doing this, whilst trying to minimise memory usage and having 1 image which will expand and shrink to fill the relvent square space(this varies on all the different screen sizes as it splits the overall screen width evenly).

Use the Canvas method public void drawBitmap (Bitmap bitmap, Rect src, RectF dst, Paint paint). Set dst to the size of the rectangle you want the entire image to be scaled into.
EDIT:
Here's a possible implementation for drawing the bitmaps in squares across on the canvas. Assumes the bitmaps are in a 2-dimensional array (e.g., Bitmap bitmapArray[][];) and that the canvas is square so the square bitmap aspect ratio is not distorted.
private static final int NUMBER_OF_VERTICAL_SQUARES = 5;
private static final int NUMBER_OF_HORIZONTAL_SQUARES = 5;
...
int canvasWidth = canvas.getWidth();
int canvasHeight = canvas.getHeight();
int squareWidth = canvasWidth / NUMBER_OF_HORIZONTAL_SQUARES;
int squareHeight = canvasHeight / NUMBER_OF_VERTICAL_SQUARES;
Rect destinationRect = new Rect();
int xOffset;
int yOffset;
// Set the destination rectangle size
destinationRect.set(0, 0, squareWidth, squareHeight);
for (int horizontalPosition = 0; horizontalPosition < NUMBER_OF_HORIZONTAL_SQUARES; horizontalPosition++){
xOffset = horizontalPosition * squareWidth;
for (int verticalPosition = 0; verticalPosition < NUMBER_OF_VERTICAL_SQUARES; verticalPosition++){
yOffset = verticalPosition * squareHeight;
// Set the destination rectangle offset for the canvas origin
destinationRect.offsetTo(xOffset, yOffset);
// Draw the bitmap into the destination rectangle on the canvas
canvas.drawBitmap(bitmapArray[horizontalPosition][verticalPosition], null, destinationRect, null);
}
}

Try the following code :
Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setFilterBitmap(true);
paint.setDither(true);
canvas.drawBitmap(bitmap, x, y, paint);
==================
You could also just reference this answer.

How to align text center to left on canvas Android

I am developing Photography apps, and for that I am using this code:
Canvas canvas = new Canvas(bmOverlay);
TextPaint paint = new TextPaint();
paint.setColor(Color.RED);
paint.setTextAlign(Align.CENTER);
paint.setTextSize(50);
paint.setFlags(Paint.ANTI_ALIAS_FLAG);
// if the background image is defined in main.xml, omit this line
canvas.drawBitmap(mBitmap, 0, 0, null);
int left = measureTextWidth(paint, InstaTextActivity.CurrentWord);
int top = measureTextHeight(paint, InstaTextActivity.CurrentWord);
left = mBitmap.getWidth() / 2 - InstaTextActivity.textCount / 2;
top = mBitmap.getHeight() / 2 - InstaTextActivity.textCount / 2;
StaticLayout layout = new StaticLayout(InstaTextActivity.CurrentWord, paint, total,
android.text.Layout.Alignment.ALIGN_NORMAL, (float) 1.0, (float) 0.0, true);
//canvas.save();
canvas.translate(left, top);
layout.draw(canvas);
//canvas.restore();
In this code I am using paint.setTextAlign(Align.CENTER). It aligns to centre, but text doesn't align center to left, instead it aligns centre to right. Also, what is the proper way to align text on canvas?
But I want

Im using
StaticLayout mTextLayout = new StaticLayout(text, mTextPaint,
canvas.getWidth(), Alignment.ALIGN_NORMAL, 1.0f, 0.0f,
false);
canvas.translate((canvas.getWidth() / 2) - (mTextLayout.getWidth() / 2), (canvas.getHeight() / 2) - ((mTextLayout.getHeight() / 2)));
to center my multi line text on a canvas

Change my mouse cursor to the polygon i click on in java

In my program in java, I have drawn these polygons in my JFrame and I want my mouse cursor to change to the one that I click on it, so by clicking again, the polygon will be drawn in the point of my click. I don't know how to do that since I don't know how to change my cursor to a polygon?

You want to create a custom cursor. The method to create and register that cursor is toolkit.createCustomCursor. Basically, create an image with an appropriate size, install it and use as needed. Here's a code snippet:
Toolkit kit = Toolkit.getDefaultToolkit();
Dimension dim = kit.getBestCursorSize(48, 48);
BufferedImage buffered = GraphicsUtilities.createCompatibleTranslucentImage(dim.width, dim.height);
Shape circle = new Ellipse2D.Float(0, 0, dim.width - 1, dim.height - 1);
Graphics2D g = buffered.createGraphics();
g.setColor(Color.BLUE);
g.draw(circle);
g.setColor(Color.RED);
int centerX = (dim.width - 1) /2;
int centerY = (dim.height - 1) / 2;
g.drawLine(centerX, 0, centerX, dim.height - 1);
g.drawLine(0, centerY, dim.height - 1, centerY);
g.dispose();
Cursor cursor = kit.createCustomCursor(buffered, new Point(centerX, centerY), "myCursor");