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@kashifrazzaqui
Created February 4, 2015 04:36
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Scaling a bitmap in android
import android.graphics.*;
import android.net.Uri;
public class BitmapFileLoader
{
public static Bitmap loadFromUri(Uri fileUri, float maxWidth, float maxHeight)
{
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile(fileUri.getPath(), options);
int actualHeight = options.outHeight;
int actualWidth = options.outWidth;
float imgRatio = actualWidth / actualHeight;
float maxRatio = maxWidth / maxHeight;
if (actualHeight > maxHeight || actualWidth > maxWidth)
{
if (imgRatio < maxRatio)
{
imgRatio = maxHeight / actualHeight;
actualWidth = (int) (imgRatio * actualWidth);
actualHeight = (int) maxHeight;
}
else if (imgRatio > maxRatio)
{
imgRatio = maxWidth / actualWidth;
actualHeight = (int) (imgRatio * actualHeight);
actualWidth = (int) maxWidth;
}
else
{
actualHeight = (int) maxHeight;
actualWidth = (int) maxWidth;
}
}
options.inSampleSize = calculateInSampleSize(options, actualWidth, actualHeight);
options.inJustDecodeBounds = false;
options.inDither = true;
options.inPurgeable = true;
options.inInputShareable = true;
options.inTempStorage = new byte[16 * 1024];
Bitmap sampledBitmap = BitmapFactory.decodeFile(fileUri.getPath(), options);
return createScaledBitmap(sampledBitmap, actualWidth, actualHeight);
}
private static int calculateInSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight)
{
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth)
{
final int heightRatio = Math.round((float) height / (float) reqHeight);
final int widthRatio = Math.round((float) width / (float) reqWidth);
inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
}
final float totalPixels = width * height;
final float totalReqPixelsCap = reqWidth * reqHeight * 2;
while (totalPixels / (inSampleSize * inSampleSize) > totalReqPixelsCap)
{
inSampleSize++;
}
return inSampleSize;
}
private static Bitmap createScaledBitmap(Bitmap src, int reqWidth, int reqHeight)
{
int width = src.getWidth();
int height = src.getHeight();
float ratioHeight = (float) height / (float) reqHeight;
float ratioWidth = (float) width / (float) reqWidth;
int scaledWidth = width;
int scaledHeight = height;
if (ratioHeight > 1 || ratioWidth > 1)
{
float maxRatio = Math.max(ratioHeight, ratioWidth);
scaledWidth = (int) (width / maxRatio);
scaledHeight = (int) (height / maxRatio);
}
return Bitmap.createScaledBitmap(src, scaledWidth, scaledHeight, true);
}
}
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