You can download the latest binary of the Android Backup Processor. Once downloaded, extract the zip file and run:
java -jar abp.jar unpack <backup.ab> <backup.tar> <password>
info: java -jar abp.jar [-debug] [-useenv=yourenv] info <backup.ab> [password]
unpack: java -jar abp.jar [-debug] [-useenv=...
I can give you part of the solution, which is that SPBM is just ZIP with the file extension changed. Most likely, SMEM is the same deal. However, once you open the ZIP file (e.g by changing the extension to ZIP), the contacts are stored in a ".BK" format, which Notepad thinks is UTF-16 LE text. I have a suspicion that it's some kind of binary-to-...