Android Bitmap Size Get computeSampleSize(BitmapFactory.Options options, int minSideLength, int maxNumOfPixels)

Description

compute Sample Size

Declaration

public static int computeSampleSize(BitmapFactory.Options options,
            int minSideLength, int maxNumOfPixels) 

Method Source Code

//package com.java2s;

import android.graphics.BitmapFactory;

public class Main {
    public static int computeSampleSize(BitmapFactory.Options options,
            int minSideLength, int maxNumOfPixels) {
        int initialSize = computeInitialSampleSize(options, minSideLength,
                maxNumOfPixels);//from  www .j a  va  2 s .  c  om

        int roundedSize;
        if (initialSize <= 8) {
            roundedSize = 1;
            while (roundedSize < initialSize) {
                roundedSize <<= 1;
            }
        } else {
            roundedSize = (initialSize + 7) / 8 * 8;
        }

        return roundedSize;
    }

    private static int computeInitialSampleSize(
            BitmapFactory.Options options, int minSideLength,
            int maxNumOfPixels) {
        double w = options.outWidth;
        double h = options.outHeight;

        int lowerBound = (maxNumOfPixels == -1) ? 1 : (int) Math.ceil(Math
                .sqrt(w * h / maxNumOfPixels));
        int upperBound = (minSideLength == -1) ? 128 : (int) Math.min(
                Math.floor(w / minSideLength),
                Math.floor(h / minSideLength));

        if (upperBound < lowerBound) {
            // return the larger one when there is no overlapping zone.
            return lowerBound;
        }

        if ((maxNumOfPixels == -1) && (minSideLength == -1)) {
            return 1;
        } else if (minSideLength == -1) {
            return lowerBound;
        } else {
            return upperBound;
        }
    }
}

Related

1. computeSampleSize(BitmapFactory.Options options, int target)
2. getBitmapSize(String filePath)
3. getImageWH(String path)
4. inSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight)
5. obtainBitmapSize(String pathName)
6. computeInitialSampleSize( BitmapFactory.Options options, int minSideLength, int maxNumOfPixels)
7. computeInitialSampleSize(int w, int h, int minSideLength, int maxNumOfPixels)
8. computeInitialSampleSize( BitmapFactory.Options options, int minSideLength, int maxNumOfPixels)
9. computeInSampleSizeForMoment(Bitmap map, int newWidth, int newHeight)