如何在Android中压缩图像

Question

How to compress the image in android application.

My application selects photo from gallery using intent and sets the photo as background for the layout,This works fine when i select a photo of small pixel,bit photo taken from camera it does not fit the screen.

how to compress the photo or image.

Answer 1

Use following intent to get image of required size from Gallery.

         Intent photoPickerIntent = new Intent(
                        Intent.ACTION_PICK,
                         android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
                // photoPickerIntent.setType("image/*");
                photoPickerIntent.putExtra("crop", "true");
                photoPickerIntent.putExtra("outputX", 512);
                photoPickerIntent.putExtra("outputY", 512);
                photoPickerIntent.putExtra("aspectX", 1);
                photoPickerIntent.putExtra("aspectY", 1);
                photoPickerIntent.putExtra("scale", true);
                File f = new File(android.os.Environment
                        .getExternalStorageDirectory(), "tt.jpg");
                // imgpath=f.getAbsolutePath();
                System.err.println("Path$$$$$$$$$ " + f.getAbsolutePath());
                photoPickerIntent.putExtra(MediaStore.EXTRA_OUTPUT,
                        Uri.fromFile(f));
                photoPickerIntent.putExtra("outputFormat",
                        Bitmap.CompressFormat.PNG.toString());
                startActivityForResult(photoPickerIntent, SELECT_FILE);

Answer 2

To measure the width and height of your Imageview at run time

ViewTreeObserver vto = mUserPicImageView.getViewTreeObserver();
    vto.addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
        public boolean onPreDraw() {

            if (mImageHeight == 0) {
                mImageHeight = mUserPicImageView.getMeasuredHeight();
                mImageWidth = mUserPicImageView.getMeasuredWidth();
                Log.e("mImageHeight", mImageHeight + "");

            }
            return true;
        }
    });

Create image of the above width and height

 Bitmap scaledBitmap = Bitmap.createScaledBitmap(bitmap,mImageHeight,mImageWidth, true);

Set the image to ImageView

mUserPicImageView.setImageBitmap(scaledBitmap);