Here you can find the source of isSupportedByRegionDecoder(String mimeType)
public static boolean isSupportedByRegionDecoder(String mimeType)
//package com.java2s; public class Main { public static boolean isSupportedByRegionDecoder(String mimeType) { if (mimeType == null) return false; mimeType = mimeType.toLowerCase(); return mimeType.startsWith("image/") && (!mimeType.equals("image/gif") && !mimeType .endsWith("bmp")); }/*from w ww . j av a 2 s .c om*/ }