private InternalImageData loadFromDisk() {
                final InternalImageData loadResult = loadImageFromStorage(url, pseudoGeocode, shared);
                loadResult.bitmapDrawable =  scaleImage(loadResult.bitmap);
                return loadResult;
            }
Caches are loaded from disk on a computation scheduler to avoid using more threads than cores while decoding
the image. Downloads happen on downloadScheduler, in parallel with image decoding.
main/src/main/java/cgeo/geocaching/network/HtmlImage.java