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Java - How to pad and resize image without cropping?

I need to resize alot of images from the ratio aspect (2:3) to (3:4).
The images are 800px x 1200px currently. I need them to be 600px x 800px eventually without any cropping.
May I know what libraries are available for me to do padding and resizing without cropping in Java?

From your current Image (assuming a java.awt.Image) you can use :
Image.getScaledInstance(w,h,h) as method
Image.SCALE_SMOOTH as algorithm for resize
And these steps:
compute the ratios in width and in height
depending on their values (padding width or padding height)
compute the width and height to obtain the scaled image
compute the padding required
write the image at the good position
static BufferedImage pad(BufferedImage image, double width, double height, Color pad) {
double ratioW = image.getWidth() / width;
double ratioH = image.getHeight() / height;
double newWidth = width, newHeight = height;
int fitW = 0, fitH = 0;
BufferedImage resultImage;
Image resize;
//padding width
if (ratioW < ratioH) {
newWidth = image.getWidth() / ratioH;
newHeight = image.getHeight() / ratioH;
fitW = (int) ((width - newWidth) / 2.0);
}//padding height
else if (ratioH < ratioW) {
newWidth = image.getWidth() / ratioW;
newHeight = image.getHeight() / ratioW;
fitH = (int) ((height - newHeight) / 2.0);
}
resize = image.getScaledInstance((int) newWidth, (int) newHeight, Image.SCALE_SMOOTH);
resultImage = new BufferedImage((int) width, (int) height, image.getType());
Graphics g = resultImage.getGraphics();
g.setColor(pad);
g.fillRect(0, 0, (int) width, (int) height);
g.drawImage(resize, fitW, fitH, null);
g.dispose();
return resultImage;
}
To use as
BufferedImage image = ...;
BufferedImage result = pad(image, 600, 800, Color.white);

Managed to do it using below code:
'w' is the amount of padding you need on each side.
BufferedImage newImage = new BufferedImage(image.getWidth()+2*w, image.getHeight(),
image.getType());
Graphics g = newImage.getGraphics();
g.setColor(Color.white);
g.fillRect(0,0,image.getWidth()+2*w,image.getHeight());
g.drawImage(image, w, 0, null);
g.dispose();

I think ffmpeg can help you to do anything with image.
e.g. Use ffmpeg to resize image
You can keep ffmpeg binaries in some conf folder.
Create sh script for ffmpeg command.
Use CommandLine from (Apache Commons exec library) to run the script.

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: Resizing Bitmaps without losing quality

i've really searched through over the entire web before posting. My problem is that i cannot resize bitmap without losing the quality of the image (the quality is really bad and pixelated).
I take the bitmap from camera and then i have to downscale it, so i can upload it to the server much faster.
This is the function that does the sampling
public Bitmap resizeBitmap(Bitmap bitmap){
Canvas canvas = new Canvas();
Bitmap resizedBitmap = null;
if (bitmap !=null) {
int h = bitmap.getHeight();
int w = bitmap.getWidth();
int newWidth=0;
int newHeight=0;
if(h>w){
newWidth = 600;
newHeight = 800;
}
if(w>h){
newWidth = 800;
newHeight = 600;
}
float scaleWidth = ((float) newWidth) / w;
float scaleHeight = ((float) newHeight) / h;
Matrix matrix = new Matrix();
// resize the bit map
matrix.preScale(scaleWidth, scaleHeight);
resizedBitmap = Bitmap.createBitmap(bitmap, 0, 0, w, h, matrix, true);
Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setFilterBitmap(true);
paint.setDither(true);
canvas.drawBitmap(resizedBitmap, matrix, paint);
}
return resizedBitmap;
and this is how i get the image from activity result
protected void onActivityResult(int requestCode, int resultCode,
Intent data) {
if(resultCode != RESULT_CANCELED){
if (requestCode == 0) {
if (resultCode == RESULT_OK) {
getContentResolver().notifyChange(mImageUri, null);
ContentResolver cr = this.getContentResolver();
try
{
b = android.provider.MediaStore.Images.Media.getBitmap(cr, mImageUri);
Log.d("foto", Integer.toString(b.getWidth()));
Log.d("foto", Integer.toString(b.getHeight()));
addPhoto.setImageBitmap(b);
}
catch (Exception e)
{
Toast.makeText(this, "Failed to load", Toast.LENGTH_SHORT).show();
Log.d("TAG", "Failed to load", e);
}
}
}
I'm starting to think that the best way to get a small picture size is to set the camera resolution. Anyone else can help?

Good downscaling algorithm (not nearest neighbor like) consists of just 2 steps (plus calculation of the exact Rect for input/output images crop):
downscale using BitmapFactory.Options::inSampleSize->BitmapFactory.decodeResource() as close as possible to the resolution that you need but not less than it
get to the exact resolution by downscaling a little bit using Canvas::drawBitmap()
Here is detailed explanation how SonyMobile resolved this task: http://developer.sonymobile.com/2011/06/27/how-to-scale-images-for-your-android-application/
Here is the source code of SonyMobile scale utils: http://developer.sonymobile.com/downloads/code-example-module/image-scaling-code-example-for-android/

Try below mentioned code for resizing bitmap.
public Bitmap get_Resized_Bitmap(Bitmap bmp, int newHeight, int newWidth) {
int width = bmp.getWidth();
int height = bmp.getHeight();
float scaleWidth = ((float) newWidth) / width;
float scaleHeight = ((float) newHeight) / height;
// CREATE A MATRIX FOR THE MANIPULATION
Matrix matrix = new Matrix();
// RESIZE THE BIT MAP
matrix.postScale(scaleWidth, scaleHeight);
// "RECREATE" THE NEW BITMAP
Bitmap newBitmap = Bitmap.createBitmap(bmp, 0, 0, width, height, matrix, false);
return newBitmap ;
}
I used this code to downsize my bitmap, and its quality, well.. , was acceptable.
Hope this helps.

Try Bitmap.createScaledBitmap.
It also has an option to filter the source.

the best rescaling method I have come across
the method uses createScaledBitmap whereby the height and width are calculated based on the bitmap height and width and a scale ratio hence quality is not lost
public Bitmap resize(Bitmap imaged, int maxWidth, int maxHeight) {
Bitmap image = imaged;
if (maxHeight > 0 && maxWidth > 0) {
int width = image.getWidth();
int height = image.getHeight();
float ratioBitmap = (float) width / (float) height;
float ratioMax = (float) maxWidth / (float) maxHeight;
int finalWidth = maxWidth;
int finalHeight = maxHeight;
if (ratioMax > 1) {
finalWidth = Math.round(((float) maxHeight * ratioBitmap));
} else {
finalHeight = Math.round(((float) maxWidth / ratioBitmap));
}
return image = Bitmap.createScaledBitmap(image, finalWidth, finalHeight, false);
}
return image;
}
how to use:
Bitmap resizedBitmap = resize(scrBitMap,640,640);

Rotate a saved bitmap in android

I am saving an image from the camera that was in landscape mode. so it gets saved in landscape mode and then i apply an overlay onto it that too is in landscape mode. I want to rotate that image and then save. e.g. if i have this
I want to rotate clockwise by 90 degrees once and make it this and save it to sdcard:
How is this to be accomplished?

void rotate(float x)
{
Bitmap bitmapOrg = BitmapFactory.decodeResource(getResources(),R.drawable.tedd);
int width = bitmapOrg.getWidth();
int height = bitmapOrg.getHeight();
int newWidth = 200;
int newHeight = 200;
// calculate the scale - in this case = 0.4f
float scaleWidth = ((float) newWidth) / width;
float scaleHeight = ((float) newHeight) / height;
Matrix matrix = new Matrix();
matrix.postScale(scaleWidth, scaleHeight);
matrix.postRotate(x);
Bitmap resizedBitmap = Bitmap.createBitmap(bitmapOrg, 0, 0,width, height, matrix, true);
iv.setScaleType(ScaleType.CENTER);
iv.setImageBitmap(resizedBitmap);
}

Check this
public static Bitmap rotateImage(Bitmap src, float degree)
{
// create new matrix
Matrix matrix = new Matrix();
// setup rotation degree
matrix.postRotate(degree);
Bitmap bmp = Bitmap.createBitmap(src, 0, 0, src.getWidth(), src.getHeight(), matrix, true);
return bmp;
}

You can use the Canvas API to do that. Note that you need to switch width and height.
final int width = landscapeBitmap.getWidth();
final int height = landscapeBitmap.getHeight();
Bitmap portraitBitmap = Bitmap.createBitmap(height, width, Bitmap.Config.ARGB_8888);
Canvas c = new Canvas(portraitBitmap);
c.rotate(90, height/2, width/2);
c.drawBitmap(landscapeBitmap, 0,0,null);
portraitBitmap.compress(CompressFormat.JPEG, 100, stream);

Use a Matrix.rotate(degrees) and draw the Bitmap to it's own Canvas using that rotating matrix. I don't know though if you might have to make a copy of the bitmap before drawing.
Use Bitmap.compress(...) to compress your bitmap to an outputstream.

The solution of Singhak works fine.
In case you need fit the size of result bitmap (perhaps for ImageView) you can expand the method as follows:
public static Bitmap rotateBitmapZoom(Bitmap bmOrg, float degree, float zoom){
Matrix matrix = new Matrix();
matrix.postRotate(degree);
float newHeight = bmOrg.getHeight() * zoom;
float newWidth = bmOrg.getWidth() / 100 * (100.0f / bmOrg.getHeight() * newHeight);
return Bitmap.createBitmap(bmOrg, 0, 0, (int)newWidth, (int)newHeight, matrix, true);
}

Changing the image width and height

I would like to change the height and width of the image. Displays the image using the canvas:
canvas.drawBitmap (_image, 0, 0, null);
How to change the size of the bitmap?

Use a Matrix:
int width = bitmap.getWidth();
int height = bitmap.getHeight();
float scaleWidth = ((float) newWidth) / width;
float scaleHeight = ((float) newHeight) / height;
matrix = new Matrix();
matrix.postScale(scaleWidth, scaleHeight);
Bitmap resizedBitmap = Bitmap.createBitmap(bitmap, 0, 0,
width, height, matrix, true);

Or Bitmap.createScaledBitmap(...)