Develop Reference

Making Bitmap aspect ratio to centerFit Android

I have searched alot for this but got no proper solution!
i have a drawing area in my android app and i want to take image from camera/gallery and set it as a background of canvas.
I get Bitmap after taking photo from camera/gallery and i pass my bitmap to this method to make it aspect fit to my drawView keeping its aspect ratio.
Here newHeight/newWidth are my drawView's height and width.
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.min(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.drawColor(Color.WHITE);
canvas.drawBitmap(source, null, targetRect, null);
return dest;
}
It works good on mt Htc m7 but on my galaxy tab4 it makes image strech so sleek as you can see in image below:
do anyone know any method through which i can set bitmap to my drawView like this
Bitmap backgroundBitMap= c.scaleCenterCrop(bmp, drawView.getHeight(), drawView.getWidth());
String tempPath = getPath(selectedImageUri, MainActivity.this);
backgroundBitMap= c.rotateImage(backgroundBitMap,tempPath);
drawView.setBackgroundDrawable(new BitmapDrawable(backgroundBitMap));
but keeping its aspect ration same. Actually i want CenterFit functionality for a bitmap.
Any help would be appreciated! Thanks

Why are images larger than the set size not being scaled down

I work out the width and height of my fragment and scale its image to a specific percentage of that fragment. This works for images that need to be scaled up to meet that size but larger images seem to ignore the scales (i think they shrink a bit but not to corretc size).
I get my imahes via http asyncTask call then on onPostexecute set the imageView control src and scale the imageView. Work for smaller images, not larger ones.
The larger image is 10kb, smaller is 1kb.
protected void onPostExecute(Bitmap result) {
bmImage.setImageBitmap(result);
if (result != null) {
int width = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_PT, 35, getContext().getResources().getDisplayMetrics());
int height = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_PT, 35, getContext().getResources().getDisplayMetrics());
bmImage.setMinimumWidth(width);
bmImage.setMinimumHeight(height);
bmImage.setMaxWidth(width);
bmImage.setMaxHeight(height);
}
I see the dimensions being calc'c correctly and afterwards set correctly in the imageView )(minimum and maxheight) but the mDrawable attr is big so perhaps this is an indicator of worng attr being set?

https://argillander.wordpress.com/2011/11/24/scale-image-into-imageview-then-resize-imageview-to-match-the-image/
private void scaleImage(ImageView view, int boundBoxInDp)
{
// Get the ImageView and its bitmap
Drawable drawing = view.getDrawable();
Bitmap bitmap = ((BitmapDrawable)drawing).getBitmap();
// Get current dimensions
int width = bitmap.getWidth();
int height = bitmap.getHeight();
// Determine how much to scale: the dimension requiring less scaling is
// closer to the its side. This way the image always stays inside your
// bounding box AND either x/y axis touches it.
float xScale = ((float) boundBoxInDp) / width;
float yScale = ((float) boundBoxInDp) / height;
float scale = (xScale <= yScale) ? xScale : yScale;
// Create a matrix for the scaling and add the scaling data
Matrix matrix = new Matrix();
matrix.postScale(scale, scale);
// Create a new bitmap and convert it to a format understood by the ImageView
Bitmap scaledBitmap = Bitmap.createBitmap(bitmap, 0, 0, width, height, matrix, true);
BitmapDrawable result = new BitmapDrawable(scaledBitmap);
width = scaledBitmap.getWidth();
height = scaledBitmap.getHeight();
// Apply the scaled bitmap
view.setImageDrawable(result);
// Now change ImageView's dimensions to match the scaled image
LinearLayout.LayoutParams params = (LinearLayout.LayoutParams) view.getLayoutParams();
params.width = width;
params.height = height;
view.setLayoutParams(params);
}

Get image dimensions after it draws in screen

I have an ImageView with MathParent height and width
In my activity it loads a pic from resource to ImageView. How can i get width and height of the picture inside the ImageView AFTER it has been scaled.
I have not set the android:scaleType in XML
these dimensions i mean!

You can do a lot with the matrix the view uses to display the image.
Here I calculate the scale the image is drawn at:
private float scaleOfImageView(ImageView image) {
float[] coords = new float[]{0, 0, 1, 1};
Matrix matrix = image.getImageMatrix();
matrix.mapPoints(coords);
return coords[2] - coords[0]; //xscale, method assumes maintaining aspect ratio
}
Applying the scale to the image dimensions gives the displayed image size:
private void logImageDisplaySize(ImageView image) {
Drawable drawable = image.getDrawable();
int width = drawable.getIntrinsicWidth();
int height = drawable.getIntrinsicHeight();
float scale = scaleOfImageView(image);
float displayedWidth = scale * width;
float displayedHeight = scale * height;
Log.d(TAG, String.format("Image drawn at scale: %.2f => %.2f x %.2f",
scale, displayedWidth, displayedHeight));
}
I suspect you don't really care about the image size, I suspect you want to map touch points back to a coordinate on the image, this answer shows how to do this (also using the image matrix): https://stackoverflow.com/a/9945896/360211

Android Image Resize basic

I like to resize an bitmap,if it is big make it small and place it on an specific location in the surface view, I need to get device width and height and then bitmap size and place them in an surface view and then take another image resize it and place it in any location has i like.
How to know the location co ordinates first(to place second image - this should be device independent if larger/smaller screen layout should not change)
and how to scale an big bitmap and set as background so i can draw an image over it.
my code :
final int canvasWidth = getWidth();
final int canvasHeight = getHeight();
int imageWidth = img.getWidth();
int imageHeight = img.getHeight();
float scaleFactor = Math.min( (float)canvasWidth / imageWidth,
(float)canvasHeight / imageHeight );
Bitmap scaled = Bitmap.createScaledBitmap( img,
(int)(scaleFactor * imageWidth),
(int)(scaleFactor * imageHeight),
true );
canvas.drawColor(Color.BLACK);
canvas.drawBitmap(scaled, 10, 10, null);
this scale the big image but it doesn't fit the whole screen "img - bitmap is like an background image "
Someone can help me to understand the resize basics (I'm new so finding hard to understand resizing) to resize image to fit screen and resize any image to smaller one and place it in any location i like .

Store your bitmap as a source for manipulation and display it using ImageView:
Bitmap realImage = BitmapFactory.decodeFile(filePathFromActivity.toString());
Bitmap newBitmap = scaleDown(realImage, MAX_IMAGE_SIZE, true);
imageView.setImageBitmap(newBitmap);
//scale down method
public static Bitmap scaleDown(Bitmap realImage, float maxImageSize,
boolean filter) {
float ratio = Math.min(
(float) maxImageSize / realImage.getWidth(),
(float) maxImageSize / realImage.getHeight());
int width = Math.round((float) ratio * realImage.getWidth());
int height = Math.round((float) ratio * realImage.getHeight());
Bitmap newBitmap = Bitmap.createScaledBitmap(realImage, width,
height, filter);
return newBitmap;
}
And set your ImageView's width and height to "fill_parent".

How to crop Bitmap Center like imageview? [duplicate]

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
How to crop the parsed image in android?
How does one crop the same way as Androids ImageView is doing
android:scaleType="centerCrop"

Your question is a bit short of information on what you want to accomplish, but I guess you have a Bitmap and want to scale that to a new size and that the scaling should be done as "centerCrop" works for ImageViews.
From Docs
Scale the image uniformly (maintain the image's aspect ratio) so that
both dimensions (width and height) of the image will be equal to or
larger than the corresponding dimension of the view (minus padding).
As far as I know, there is no one-liner to do this (please correct me, if I'm wrong), but you could write your own method to do it. The following method calculates how to scale the original bitmap to the new size and draw it centered in the resulting Bitmap.
Hope it helps!
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;
}