图片在压缩文件中，我先用BitmapFactory取图片尺寸，计算之后再按照合适尺寸取出Bitmap，代码如下：
options.inJustDecodeBounds = true; BitmapFactory.decodeStream(imgInputStream, null, options); options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight); options.inJustDecodeBounds = false; return BitmapFactory.decodeStream(imgInputStream, null, options);
SkImageDecoder::Factory returned null
// we need mark/reset to work properly
if (!is.markSupported()) {
is = new BufferedInputStream(is, DECODE_BUFFER_SIZE);
}
// so we can call reset() if a given codec gives up after reading up to
// this many bytes. FIXME: need to find out from the codecs what this
// value should be.
is.mark(1024); 于是看明白了，第一次取图片尺寸的时候is这个InputStream被使用过了，再真正取图片的时候又使用了这个InputStream，此时流的起始位置已经被移动过了，需要调用is.reset()来重置，然后再decodeStream(imgInputStream,
null, options)就没问题了。 SkImageDecoder::Factory returned null
原文：http://blog.csdn.net/jianqiao_liu/article/details/39205293