Java tutorial
//package com.java2s; import android.content.Context; import android.graphics.BitmapFactory; public class Main { public static float getBitmapRatio(Context context, int resourceId) { BitmapFactory.Options options = new BitmapFactory.Options(); options.inJustDecodeBounds = true; BitmapFactory.decodeResource(context.getResources(), resourceId, options); return options.outHeight / (float) options.outWidth; } }