BitmapDecoder.java

package de.danoeh.antennapodsp.util;

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Rect;
import android.util.Log;
import de.danoeh.antennapodsp.AppConfig;
import de.danoeh.antennapodsp.asynctask.ImageLoader;
import org.apache.commons.io.IOUtils;

import java.io.InputStream;

public class BitmapDecoder {
    private static final String TAG = "BitmapDecoder";

    private static int calculateSampleSize(int preferredLength, int length) {
        int sampleSize = 1;
        if (length > preferredLength) {
            sampleSize = Math.round(((float) length / (float) preferredLength));
        }
        return sampleSize;
    }

    public static Bitmap decodeBitmapFromWorkerTaskResource(int preferredLength,
                                                            ImageLoader.ImageWorkerTaskResource source) {
        InputStream input = source.openImageInputStream();
        if (input != null) {
            BitmapFactory.Options options = new BitmapFactory.Options();
            options.inJustDecodeBounds = true;
            BitmapFactory.decodeStream(input, new Rect(), options);
            int srcWidth = options.outWidth;
            int srcHeight = options.outHeight;
            int length = Math.max(srcWidth, srcHeight);
            int sampleSize = calculateSampleSize(preferredLength, length);
            if (AppConfig.DEBUG)
                Log.d(TAG, "Using samplesize " + sampleSize);
            options.inJustDecodeBounds = false;
            options.inSampleSize = sampleSize;
            options.inPreferredConfig = Bitmap.Config.ARGB_8888;
            Bitmap decodedBitmap = BitmapFactory.decodeStream(source.reopenImageInputStream(input),
                    null, options);
            if (decodedBitmap == null) {
                decodedBitmap = BitmapFactory.decodeStream(source.reopenImageInputStream(input));
            }
            IOUtils.closeQuietly(input);
            return decodedBitmap;
        }
        return null;
    }
}