inSampleSize is a good hint. But a fixed value often doesn’t work fine, since large bitmaps from files usually are user files, which can vary from tiny thumbnails to 12MP images from the digicam.
Here’s a quick and dirty loading routine. I know there’s room for improvement, like a nicer coded loop, using powers of 2 for faster decoding, and so on. But it’s a working start…
public static Bitmap loadResizedBitmap( String filename, int width, int height, boolean exact ) {
Bitmap bitmap = null;
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile( filename, options );
if ( options.outHeight > 0 && options.outWidth > 0 ) {
options.inJustDecodeBounds = false;
options.inSampleSize = 2;
while ( options.outWidth / options.inSampleSize > width
&& options.outHeight / options.inSampleSize > height ) {
options.inSampleSize++;
}
options.inSampleSize--;
bitmap = BitmapFactory.decodeFile( filename, options );
if ( bitmap != null && exact ) {
bitmap = Bitmap.createScaledBitmap( bitmap, width, height, false );
}
}
return bitmap;
}
Btw, in the newer APIs there are also lots of BitmapFactory.Option’s for fitting the image to screen DPIs, but I’m not sure whether they really simplify anything. Using android.util.DisplayMetrics.density or simply a fixed size for less memory consumption seem to work better imho.